make - forge? - wedge for feathers-and-wedge rock-split

[Richard Smith]

Hello all

Setting the scene:

"feathers" work well for splitting boulders so can be removed as
handleable rocks.
Lots of videos online eg. YouTube how to use them.

The ones I have:

Loading Image...

from page
http://www.weldsmith.co.uk/tech/minerals/240314_rocksplit/240314_rocksplit_drill_feathers.html
"Rock-split granite with "cordless" SDS drill and "feathers""

They work really well.
But these "10mm" feathers need a 14mm-dia socket.
The wedge is visibly oversized=overthickness for the feathers.
Saving just two mm of thickness would surely enable using a 12mm
socket. Useful saving on drilling (14mm -> 12mm)
(/ (expt 12 2) (float (expt 14 2))) ;; 0.7346938775510204
73% of vol drilled - and the impact is concentrated on the smaller
cutting tip.


The question:

How would you go about producting wedges about 2mm to 3mm thinner than
the current ones?

Doing something to the current wedges would be okay.

Making them anew with something like forging could be a good project.
If so what steel would you use? AISI1075? (C-Mn; 0.75%C). If so -
"spring-temper"?

We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).

Always appreciated the range of knowledge here.

Regards,
Rich Smith

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

How would you go about producting wedges about 2mm to 3mm thinner than
the current ones?

-------------------------------------------
The wedges in my 1/2" set are 0.50" thick at the large end. When a set is
placed in a half inch drill gage hole the wedge freely enters about 1/4 its
length.

Without annealing them 2-3mm isn't an outrageous amount to grind off,
relative to the alternatives. With annealing it's easy on a milling machine
(again), and they are small enough to reharden without a proper forge. Mine
from T&H mushroom slightly with use, they definitely aren't brittle hard.

Do you plan to make or buy them? They should be a fairly easy shape to forge
from round stock which is more available than bar in higher carbon grades. I
made my first wedges from mild steel which doesn't hold up well, they do
need to be hardened. Wedges can be bandsawn from plate by shifting the guide
fence to half the angle and flipping the stock after each cut. The difficult
part may be finding hardenable steel bar stock in a small, inexpensive
quantity. Perhaps the worn cutting edge from a road plow or bucket loader?

I took a night class in blacksmithing to gain access to instruction, a
larger anvil and a better forge than my woodstove, which isn't really hot
enough. I have the parts for a forge but not a safe place to use it.

[Peter Fairbrother]

Post by Richard Smith
Making them anew with something like forging could be a good project.
If so what steel would you use? AISI1075? (C-Mn; 0.75%C). If so -
"spring-temper"?

I'd probably use O1 ground flat stock, but only because it is readily
available. Can be cut on a bandsaw in as-it-arrives condition. Not
cheap, but you can sometimes find a deal.

Slowly heat to red-orange, soak for 15 minutes. Quench in hot oil, then
immediately temper well, don't let it cool from hot oil temperature: you
don't want it too hard - maybe an hour or two at 250 C. You'll still be
around 60 Rockwell C.

Not sure if you can spring temper O1. I wouldn't try it here.

That old favourite EN24T might work too, but it is hard to find except
in round bar.

Post by Richard Smith
We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).

It's great for hard stuff like knives or screwdrivers: but if you need
impact resistance you have to temper it so much it gets soft; or at
least that's my limited experience, ymmv. I know some people have used
it for punches.

Another problem is, again, it's only really available in round bar.



Peter Fairbrother

[Joe Gwinn]

On Fri, 29 Mar 2024 17:40:58 +0000, Peter Fairbrother

Post by Peter Fairbrother

Post by Richard Smith
Making them anew with something like forging could be a good project.
If so what steel would you use? AISI1075? (C-Mn; 0.75%C). If so -
"spring-temper"?

I'd probably use O1 ground flat stock, but only because it is readily
available. Can be cut on a bandsaw in as-it-arrives condition. Not
cheap, but you can sometimes find a deal.
Slowly heat to red-orange, soak for 15 minutes. Quench in hot oil, then
immediately temper well, don't let it cool from hot oil temperature: you
don't want it too hard - maybe an hour or two at 250 C. You'll still be
around 60 Rockwell C.
Not sure if you can spring temper O1. I wouldn't try it here.
That old favourite EN24T might work too, but it is hard to find except
in round bar.

Post by Richard Smith
We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).

It's great for hard stuff like knives or screwdrivers: but if you need
impact resistance you have to temper it so much it gets soft; or at
least that's my limited experience, ymmv. I know some people have used
it for punches.
Another problem is, again, it's only really available in round bar.

What about S7 steel:

.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-rods-and-discs/>

.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-bars/>

Or 1045 steel:

.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-sheets-and-bars/>

.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-rods-and-discs/>

Or 4340 steel:

.<https://www.mcmaster.com/products/metals/steel~/high-strength-4340-alloy-steel-rods/>


Joe Gwinn

[Peter Fairbrother]

Post by Joe Gwinn
On Fri, 29 Mar 2024 17:40:58 +0000, Peter Fairbrother

Post by Peter Fairbrother
I'd probably use O1 ground flat stock, but only because it is readily
available.

.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-sheets-and-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-4340-alloy-steel-rods/>

All good choices.

Ah yes the wonderful McMaster-Carr. Unfortunately they only sell to
VAT-registered businesses in the UK, and shipping starts at about $300
(ouch!!).

You can get 4340 and S7 in the UK, but I don't know where you could get
suitable flats to make wedges in reasonable small quantities.

1045 is about the same as EN8, which is sold a bit more widely, but
again I don't know where to get suitable flats in small quantities.

EN9 would do better (quench-hardens, unlike EN8), but again I don't know
where to buy suitable flats.

Anyone?


The only reason I suggested O1 ground flat stock is because it is
readily available in the UK, eg on ebay, in small quantities. And it's
suitably strong and hard, it's obviously flat not round bar, and can be
had in the right size for about £40 for 500mm delivered. Not cheap, but
I don't know where to do better, especially if you include carriage.
There are occasional bargains to be had too.

80 x 12 x 500mm, £40.50
https://www.ebay.co.uk/itm/395054999101
80 x 10 x 500mm £38.82
https://www.ebay.co.uk/itm/143198127946

Not sure how thick or wide you might want.


Actually, I'd buy wedges rather than make them, but ymmv.


Peter Fairbrother

[Jim Wilkins]

"Peter Fairbrother" wrote in message news:uu923r$10hru$***@dont-email.me...
...
Actually, I'd buy wedges rather than make them, but ymmv.
Peter Fairbrother

-----------------------------------------
Their cost suggests Black Forest elves make them by hand. We're spoiled by
the economy of mass production, of items whose sales volume justifies it.
Custom hand work is still expensive to buy, or to obtain the equipment to
make. I justified mine because it let me control all of a project at work.

I bought my wedges and shims after trying to make them, mostly because the
shims/feathers are a difficult shape to hold while machining.

[Peter Fairbrother]

Post by Jim Wilkins
Their cost suggests Black Forest elves make them by hand.

Eek!

We're spoiled

Post by Jim Wilkins
by the economy of mass production, of items whose sales volume justifies
it. Custom hand work is still expensive to buy, or to obtain the
equipment to make. I justified mine because it let me control all of a
project at work.
I bought my wedges and shims after trying to make them, mostly because
the shims/feathers are a difficult shape to hold while machining.

Are the insides of the feathers straight?

Hmm, a clamp couple of feet of 1/2" round bar in a good pipe vice, use a
thickish slitting saw on t'mill, cut off when you have them long enough,
reclamp, rinse and repeat..



noisy though :)

Peter Fairbrother

[Jim Wilkins]

"Peter Fairbrother" wrote in message news:uu999l$128v0$***@dont-email.me...

Are the insides of the feathers straight?

Hmm, a clamp couple of feet of 1/2" round bar in a good pipe vice, use a
thickish slitting saw on t'mill, cut off when you have them long enough,
reclamp, rinse and repeat..

noisy though :)

Peter Fairbrother
--------------------------------
No, they are tapered to match their side of the wedge, and the end that
protrudes from the hole is quite thin. I think chatter would be a problem
unless they were supported near the cut, and extended plus lowered in steps
as it proceeds. Or they could be slit from mild steel rod stock in a jig
that supports them at the angle.

They need to apply pressure evenly over their length, else the rock will
just chip off at the hole mouth.
https://trowandholden.com/wedge-shim-sets.html

[Peter Fairbrother]

Post by Peter Fairbrother
Are the insides of the feathers straight?

[...]

Post by Peter Fairbrother
No, they are tapered to match their side of the wedge, and the end that
protrudes from the hole is quite thin. I think chatter would be a
problem unless they were supported near the cut, and extended plus
lowered in steps as it proceeds. Or they could be slit from mild steel
rod stock in a jig that supports them at the angle.
They need to apply pressure evenly over their length, else the rock will
just chip off at the hole mouth.
https://trowandholden.com/wedge-shim-sets.html

OK, a bandsaw then shaping in a fixture on the mill then.

Matey next door says they can be made so that either the bottom is
slightly thicker than a simple wedge, or the wedge is thinned at the
top, so that the maximum pressure is at the bottom. I don't know whether
that is necessary, trowandholden don't seem to do it, some others do.


I was watching a video about Hilti capping rock, seems easy enough, if a
little energetic.

You don't need a license to buy Hilti cartridges in the UK, though maybe
you shouldn't if you have a criminal record.

Peter Fairbrother

[Joe Gwinn]

On Sat, 30 Mar 2024 12:25:20 -0400, "Jim Wilkins"

Post by Peter Fairbrother
Are the insides of the feathers straight?
Hmm, a clamp couple of feet of 1/2" round bar in a good pipe vice, use a
thickish slitting saw on t'mill, cut off when you have them long enough,
reclamp, rinse and repeat..
noisy though :)
Peter Fairbrother
--------------------------------
No, they are tapered to match their side of the wedge, and the end that
protrudes from the hole is quite thin. I think chatter would be a problem
unless they were supported near the cut, and extended plus lowered in steps
as it proceeds. Or they could be slit from mild steel rod stock in a jig
that supports them at the angle.

It occurs to me that there is a standard way to hold such awkward
items for machining: embed it in solid epoxy, which is later burned
off.

Or, soft-solder the workpiece to a larger bit of mild steel. When
complete, unsolder and shake the excess off - the remaining solder
will lubricate things.

Post by Peter Fairbrother
They need to apply pressure evenly over their length, else the rock will
just chip off at the hole mouth.
<https://trowandholden.com/wedge-shim-sets.html>

Do we have any idea what kind of steel they use?

Joe Gwinn

[Jim Wilkins]

"Joe Gwinn" wrote in message news:***@4ax.com...
On Sat, 30 Mar 2024 12:25:20 -0400, "Jim Wilkins"
Do we have any idea what kind of steel they use?
Joe Gwinn
----------------------------
The feathers are soft and flexible, the wedge harder, such that it puts
scrape marks on the feathers but not vice versa. The wedge heads have become
slightly mushroomed. The feathers are all warped from use, I'd have to
carefully straighten some to reconstruct the original geometry.

The feathers for the 5x 1/2" set and the single 3/4" were all made from 3/8"
round rod. The large end is a half circle. I chose 1/2" after finding
several new 1/2" spline drive bits from an auction in a second hand tool
store (that's closing).

I suppose the feathers could be cut freehand endwise on an upright bandsaw
if the stock was tightly clamped in an inverted toolmakers vise to keep it
from twisting when the blade was off center, then beltsanded to smooth
ridges. I bandsawed some oak slab scrap into a batch of wedges freehand to
pencil lines that came out straight and smooth enough for the carpenter
neighbor to think I bought them until sunshine revealed the saw marks.

[Jim Wilkins]

"Jim Wilkins" wrote in message news:uu9t7t$173fs$***@dont-email.me...

The feathers for the 5x 1/2" set and the single 3/4" were all made from 3/8"
round rod. The large end is a half circle. I chose 1/2" after finding
several new 1/2" spline drive bits from an auction in a second hand tool
store (that's closing).

I suppose the feathers could be cut freehand endwise on an upright bandsaw
if the stock was tightly clamped in an inverted toolmakers vise to keep it
from twisting when the blade was off center, then beltsanded to smooth
ridges.
---------------------------------------
On closer examination they appear to have been diagonally split lengthwise
with a horizontal bandsaw, the scratches slightly angled too, leaving the
large end about 1/4" thick, plus or minus several hairs.

I think a horizontal bandsaw plus a drill press could make this fixture:

Perhaps two short end blocks drilled 11/32" through and 3/8 part way, to
axially clamp the 3/8" OD blank. The space between them allows inserting and
removing the part. The bandsaw cuts its own slot. The shutoff tab is
extended to stop the saw before it slices the fixture base, thus the
slightly angled kerf marks. The base might be tilted closer to the blade
angle. Turn the vise to the diagonal angle.

Initial setup centers the blade over the middle of the blank, afterwards
lower the blade into the slot before tightening the vise.

To simplify machining the moving end clamp block could be on a pivot arm
instead of a slot, which also moves the toggle clamp away from the blade. An
eccentric pivot bushing would permit small angular error correction.

[Joe Gwinn]

On Sat, 30 Mar 2024 16:37:50 -0400, "Jim Wilkins"

Post by Joe Gwinn
On Sat, 30 Mar 2024 12:25:20 -0400, "Jim Wilkins"
Do we have any idea what kind of steel they use?
Joe Gwinn
----------------------------
The feathers are soft and flexible, the wedge harder, such that it puts
scrape marks on the feathers but not vice versa. The wedge heads have become
slightly mushroomed. The feathers are all warped from use, I'd have to
carefully straighten some to reconstruct the original geometry.
The feathers for the 5x 1/2" set and the single 3/4" were all made from 3/8"
round rod. The large end is a half circle. I chose 1/2" after finding
several new 1/2" spline drive bits from an auction in a second hand tool
store (that's closing).
I suppose the feathers could be cut freehand endwise on an upright bandsaw
if the stock was tightly clamped in an inverted toolmakers vise to keep it
from twisting when the blade was off center, then beltsanded to smooth
ridges. I bandsawed some oak slab scrap into a batch of wedges freehand to
pencil lines that came out straight and smooth enough for the carpenter
neighbor to think I bought them until sunshine revealed the saw marks.

If one can solder the wedge to something solid, all manner of
machining operations become easy.

Use eutectic tin-lead solder for lowest melting point.

Or just forge them. My bet is that the commercial wedges are made of
1045 steel (EN9 in the UK), quenched and tempered, with wedges
tempered harder than the feathers.

Probably in Roman times, they were made of wrought iron.

Joe Gwinn

[Jim Wilkins]

"Joe Gwinn" wrote in message news:***@4ax.com...

Probably in Roman times, they were made of wrought iron.

Joe Gwinn
--------------------------------------
Or bronze, the Romans were masters of it.
https://www.valvemagazine.com/articles/ancient-roman-valves

Like copper today none was left lying around.
https://www.atouchofrome.com/pantheon-explained-page-2.html#melting-of-the-pantheon-bronze-roof-trusses

The little remaining evidence of ancient tools suggests that they didn't
change much from antiquity until the Industrial Revolution, look in an
antique shop for examples. One difference is that screws were very rare
until clock makers needed them.

Holtzapffel Book II, Chapter XXVI describes the history of laying out and
forming threads by simple methods before the modern screw-cutting lathe was
introduced. I have an old die stock with grooves for gradually pressing
threads into a rod by tightening the two halves together that appear to have
been cut with a chisel.

A great advance was a lathe with a sliding spindle with several thread
pitches cut on it, so it would advance the work past a stationary cutter at
the pitch selected by lowering a follower into one of the spindle threads.

[Joe Gwinn]

On Sat, 30 Mar 2024 20:07:00 -0400, "Jim Wilkins"

Post by Joe Gwinn
Probably in Roman times, they were made of wrought iron.
Joe Gwinn
--------------------------------------
Or bronze, the Romans were masters of it.
<https://www.valvemagazine.com/articles/ancient-roman-valves>

Simple and reliable.

And the modern names of many plumbing items are based on the Latin
terms, and are more descriptive than politically correct.

Post by Joe Gwinn
Like copper today none was left lying around.
<https://www.atouchofrome.com/pantheon-explained-page-2.html#melting-of-the-pantheon-bronze-roof-trusses>

Yes, and also true of the Egyptians who preceded the Romans. Very few
bronze tools were found around the pyramids and the like.

Iron was too expensive to use for anything but knives and swords for
centuries, so bronze endured. I don't know the exact historical
sequence, but steel (versus cast iron) kept getting cheaper.

Bronze knives cannot be made sharp enough for many things, so the
Egyptians used obsidian knives, and had a guild devoted to production
and use of obsidian knives, in particular for preparing the dead for
mummification.

Post by Joe Gwinn
The little remaining evidence of ancient tools suggests that they didn't
change much from antiquity until the Industrial Revolution, look in an
antique shop for examples. One difference is that screws were very rare
until clock makers needed them.
Holtzapffel Book II, Chapter XXVI describes the history of laying out and
forming threads by simple methods before the modern screw-cutting lathe was
introduced. I have an old die stock with grooves for gradually pressing
threads into a rod by tightening the two halves together that appear to have
been cut with a chisel.

I think I read that as well.

I've read many books on how screw threads were cut in the old days
when there was a screwcutters guild. Think olive and wine presses,
and later the printing press.

Most threads were hand cut into wooden rods and nuts, usually with a
specially shaped chisel, often following a string carefully spiral
wrapped around the rod to be threaded.

The nut would usually be cut by making a metal tap, by the process for
threading a rod. There were many ways.

Post by Joe Gwinn
A great advance was a lathe with a sliding spindle with several thread
pitches cut on it, so it would advance the work past a stationary cutter at
the pitch selected by lowering a follower into one of the spindle threads.

Yes. What followed was the classical change-gear thread cutting lathe
of Henry Maudslay, circa 1800, which is the prototype for all
subsequent toolroom manual lathes to the present day, more than two
centuries later. While digital control is now replacing many of the
gear trains in modern lathes, most of Maudslay's approach endures.

.<https://en.wikipedia.org/wiki/Henry_Maudslay>

Joe Gwinn

[David Billington]

Post by Joe Gwinn
On Sat, 30 Mar 2024 16:37:50 -0400, "Jim Wilkins"

Post by Joe Gwinn
On Sat, 30 Mar 2024 12:25:20 -0400, "Jim Wilkins"
Do we have any idea what kind of steel they use?
Joe Gwinn
----------------------------
The feathers are soft and flexible, the wedge harder, such that it puts
scrape marks on the feathers but not vice versa. The wedge heads have become
slightly mushroomed. The feathers are all warped from use, I'd have to
carefully straighten some to reconstruct the original geometry.
The feathers for the 5x 1/2" set and the single 3/4" were all made from 3/8"
round rod. The large end is a half circle. I chose 1/2" after finding
several new 1/2" spline drive bits from an auction in a second hand tool
store (that's closing).
I suppose the feathers could be cut freehand endwise on an upright bandsaw
if the stock was tightly clamped in an inverted toolmakers vise to keep it
from twisting when the blade was off center, then beltsanded to smooth
ridges. I bandsawed some oak slab scrap into a batch of wedges freehand to
pencil lines that came out straight and smooth enough for the carpenter
neighbor to think I bought them until sunshine revealed the saw marks.

If one can solder the wedge to something solid, all manner of
machining operations become easy.
Use eutectic tin-lead solder for lowest melting point.
Or just forge them. My bet is that the commercial wedges are made of
1045 steel (EN9 in the UK), quenched and tempered, with wedges
tempered harder than the feathers.
Probably in Roman times, they were made of wrought iron.
Joe Gwinn

I was thinking along the lines of forging if I wanted to make a number
of these. It would be fairly simple to make some forging dies for my
flypress and them forge them down from square or round stock.

[Jim Wilkins]

"David Billington" wrote in message news:uua9p1$19vvs$***@dont-email.me...

I was thinking along the lines of forging if I wanted to make a number
of these. It would be fairly simple to make some forging dies for my
flypress and them forge them down from square or round stock.
--------------------------------

When we sore-armed students drooled over the smith's trip hammer he warned
us that one needs to understand manual forging very well first, as things
can go wrong awfully fast with it.

After considering the cost and time for the alternatives I'll buy more if I
need them. My spring shop time will likely be spent on upgrading the
capacity and durability of the sawmill. The blade guides are skateboard
bearings from a smaller previous sawmill and don't last long at 90 km/h.

[Joe Gwinn]

On Sat, 30 Mar 2024 12:55:23 +0000, Peter Fairbrother

Post by Peter Fairbrother

Post by Joe Gwinn
On Fri, 29 Mar 2024 17:40:58 +0000, Peter Fairbrother

Post by Peter Fairbrother
I'd probably use O1 ground flat stock, but only because it is readily
available.

.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-sheets-and-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-4340-alloy-steel-rods/>

All good choices.
Ah yes the wonderful McMaster-Carr. Unfortunately they only sell to
VAT-registered businesses in the UK, and shipping starts at about $300
(ouch!!).

Ouch for sure.

Post by Peter Fairbrother
You can get 4340 and S7 in the UK, but I don't know where you could get
suitable flats to make wedges in reasonable small quantities.
1045 is about the same as EN8, which is sold a bit more widely, but
again I don't know where to get suitable flats in small quantities.
EN9 would do better (quench-hardens, unlike EN8), but again I don't know
where to buy suitable flats.
Anyone?
The only reason I suggested O1 ground flat stock is because it is
readily available in the UK, eg on ebay, in small quantities. And it's
suitably strong and hard, it's obviously flat not round bar, and can be
had in the right size for about £40 for 500mm delivered. Not cheap, but
I don't know where to do better, especially if you include carriage.
There are occasional bargains to be had too.
80 x 12 x 500mm, £40.50
<https://www.ebay.co.uk/itm/395054999101>
80 x 10 x 500mm £38.82
<https://www.ebay.co.uk/itm/143198127946>

Well, I don't know UK markets, but I would expect that there are
European makers of these steels by one name or another. And they may
have an even better answer.

As Jim W says, hot forging is probably the better way to make these
feathers. I think that most of the other alloys can be forged and
maybe forge welded as well, but didn't really dig into it. Maybe the
solution is to choose and bring alloy steel rod to a local blacksmith.

Joe Gwinn

[David Billington]

Post by Peter Fairbrother

Post by Joe Gwinn
On Fri, 29 Mar 2024 17:40:58 +0000, Peter Fairbrother

Post by Peter Fairbrother
I'd probably use O1 ground flat stock, but only because it is readily
available.

.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-sheets-and-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-4340-alloy-steel-rods/>

All good choices.
Ah yes the wonderful McMaster-Carr. Unfortunately they only sell to
VAT-registered businesses in the UK, and shipping starts at about $300
(ouch!!).
You can get 4340 and S7 in the UK, but I don't know where you could
get suitable flats to make wedges in reasonable small quantities.
1045 is about the same as EN8, which is sold a bit more widely, but
again I don't know where to get suitable flats in small quantities.
EN9 would do better (quench-hardens, unlike EN8), but again I don't
know where to buy suitable flats.
Anyone?
The only reason I suggested O1 ground flat stock is because it is
readily available in the UK, eg on ebay, in small quantities. And it's
suitably strong and hard, it's obviously flat not round bar, and can
be had in the right size for about £40 for 500mm delivered. Not cheap,
but I don't know where to do better, especially if you include
carriage. There are occasional bargains to be had too.
80 x 12 x 500mm, £40.50
https://www.ebay.co.uk/itm/395054999101
80 x 10 x 500mm £38.82
https://www.ebay.co.uk/itm/143198127946
Not sure how thick or wide you might want.
Actually, I'd buy wedges rather than make them, but ymmv.
Peter Fairbrother

I've got some 6mm EN8 plate that I could part with some bits of. I've
had items profiled out of it so some sections aren't much use for much
else and would easily make the wedges I expect.

[Richard Smith]

Post by David Billington

<lots of helpful answers>

I've got some 6mm EN8 plate that I could part with some bits of. I've
had items profiled out of it so some sections aren't much use for much
else and would easily make the wedges I expect.

Hi David
If easy to send. Sounds perfect. Would reimburse postage.
On my website
weldsmith.co.uk
there is a contact form.
To first "handshake".
Typically you'd pass me a phone number or email address.
Rich Smith

[Richard Smith]

Thanks for correcting me that EN8 is 0.4%C steel.
So long since worked with these.

All of you - thanks a lot, as always.

[Peter Fairbrother]

Post by Joe Gwinn
.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-bars/>

1/2" x 3" x 18" - $131.30 (but also 1/2 x 4" at $7.82 per inch, wot?)

Post by Joe Gwinn
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-sheets-and-bars/>

10mm x 60mm x 12" - $57.65

Post by Joe Gwinn
.<https://www.mcmaster.com/products/metals/steel~/high-strength-4340-alloy-steel-rods/>

Round bars only.



Hmmm, £40 for 80x12x500mm seems not that bad..

Peter Fairbrother

[Richard Smith]

Post by Joe Gwinn
On Fri, 29 Mar 2024 17:40:58 +0000, Peter Fairbrother

Post by Peter Fairbrother

Post by Richard Smith
Making them anew with something like forging could be a good project.
If so what steel would you use? AISI1075? (C-Mn; 0.75%C). If so -
"spring-temper"?

I'd probably use O1 ground flat stock, but only because it is readily
available. Can be cut on a bandsaw in as-it-arrives condition. Not
cheap, but you can sometimes find a deal.
Slowly heat to red-orange, soak for 15 minutes. Quench in hot oil, then
immediately temper well, don't let it cool from hot oil temperature: you
don't want it too hard - maybe an hour or two at 250 C. You'll still be
around 60 Rockwell C.
Not sure if you can spring temper O1. I wouldn't try it here.
That old favourite EN24T might work too, but it is hard to find except
in round bar.

Post by Richard Smith
We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).

It's great for hard stuff like knives or screwdrivers: but if you need
impact resistance you have to temper it so much it gets soft; or at
least that's my limited experience, ymmv. I know some people have used
it for punches.
Another problem is, again, it's only really available in round bar.

.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/oversized-shock-resistant-s7-tool-steel-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-sheets-and-bars/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-1045-carbon-steel-rods-and-discs/>
.<https://www.mcmaster.com/products/metals/steel~/high-strength-4340-alloy-steel-rods/>
Joe Gwinn

I think 4340 is EN24 which Peter F mentioned. C-Cr-Mo-Ni steel.
Through-hardens readily - can quench in oil.

Minded to find some C-steel and see how it pans-out.
Would learn a lot along the way for sure - before starting with
higher-value material.

Peter F's "O1" steel sounds interesting.
C-Cr-W-V steel.
Description makes it sound like created by smart pragmatists.

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

Minded to find some C-steel and see how it pans-out.
Would learn a lot along the way for sure - before starting with
higher-value material.

Peter F's "O1" steel sounds interesting.
C-Cr-W-V steel.
Description makes it sound like created by smart pragmatists.

-----------------------------------

I might check local fabricators or heavy equipment repair shops for scrap
AR400 or similar to sell and see if my plasma cutter can handle it. Some
jackhammer bits have a similar cross section, but are wider.

[Jim Wilkins]

"Jim Wilkins" wrote in message news:uuekcs$2ij70$***@dont-email.me...

I might check local fabricators or heavy equipment repair shops for scrap
AR400 or similar to sell and see if my plasma cutter can handle it. Some
jackhammer bits have a similar cross section, but are wider.

-------------------------------------
Do you have snow plows over there?

A neighbor is welding a new cutting edge onto the bucket of his tractor.
It's a strip of high carbon steel 1/2" thick, a shorter cutoff from wear
edge repair material for Fisher snow plow blades. It's not drilled or
painted so it might be a cheaper substitute of hot rolled steel.
https://www.etrailer.com/Snow-Plow-Parts/SAM/3371301300.html?feed=npn&gad_source=1

[Joe Gwinn]

On Mon, 1 Apr 2024 11:37:33 -0400, "Jim Wilkins"

Post by Richard Smith
Minded to find some C-steel and see how it pans-out.
Would learn a lot along the way for sure - before starting with
higher-value material.
Peter F's "O1" steel sounds interesting.
C-Cr-W-V steel.
Description makes it sound like created by smart pragmatists.
-----------------------------------
I might check local fabricators or heavy equipment repair shops for scrap
AR400 or similar to sell and see if my plasma cutter can handle it. Some
jackhammer bits have a similar cross section, but are wider.

O-1 steel is very common in the US for one-off designs, where
quantities are too small to make sourcing the perfect steel
worthwhile. It can be quenched and tempered quite hard or quite
tough.

.<https://www.mcmaster.com/products/steel/material~o1-tool-steel/>

Another very common steel for such is W-1, which is iron with about 1%
carbon. W-1 is far cheaper and easier to use than O-1, can be even
harder than O-1, and so is used for making very sharp cutting edges.
It can also be made quite tough.

.<https://www.mcmaster.com/products/steel/material~w1-tool-steel/>


Give that the wedge and feathers device has been around since the
Bronze Age, I would just try what's any steel that's at hand.

Joe Gwinn

[Richard Smith]

Hi everyone
Ground 3 of the current wedges so looks like wedge-and-feathers will fit
into 12mm drilled socket.
See where that gets me for now.
Appreciating all the inputs.
I will want to forge something which has to cut.
Thanks everyone.

[Peter Fairbrother]

Post by Richard Smith
Hi everyone
Ground 3 of the current wedges so looks like wedge-and-feathers will fit
into 12mm drilled socket.
See where that gets me for now.
Appreciating all the inputs.
I will want to forge something which has to cut.
Thanks everyone.

Did you look at capping? Seems simple enough, and couldn't be cheaper
(if you already have a drill) - some old carpet, a hammer, a steel rod
with a machined end, and a £10 box of caps.

You only need to drill 8mm holes, and though you might want to drill
them a little deeper than for wedge and feathers, you need less of them.
Wedge and feathers is about cutting straight surfaces, capping is more
about smashing big rocks into smaller ones.

While it's good for breaking boulders, I don't know if the technique
could be used on a face; but cavers use it a lot to open up leads, so
maybe. Probably work, but it might be a bit slow on a face though.

Peter Fairbrother

[Richard Smith]

I'll look into this.
"In the moment" response - this is using small charges about the size of
an "AAA" battery?

I've seen videos of in the USA. Apparently given a specific exemption
as "not explosives" because they won't detonate "unconfined". That
while for-purpose, are engineered to be impossible to use for nefarious
puposes...
???

If so, didn't know you could get them in the UK. Assumed without
checking that like side-arms - what you are free to do in the US and is
normal is completely prohibited here...
Cavers use...
Can visualise that - crawling along in a tiny space, having to carry
any kit in such journey, and no space to swing a sledgehammer if you
come to an obstruction...

Apologies if "got the wrong end of the stick".

Rich S

[Peter Fairbrother]

Post by Richard Smith
I'll look into this.
"In the moment" response - this is using small charges about the size of
an "AAA" battery?

No, those are "snappers". Cavers did and apparently do use them
sometimes in the UK, but they are very coy about talking about them,
possibly because their legal status is questionable. I don't know
anywhere or even if you can buy them.


Capping or Hilti capping uses Hilti nail gun gun cartridges, which you
can get on ebay, from Hilti, in hardware stores and elsewhere, without
paperwork.

https://www.ebay.co.uk/itm/225952485669 at £15 for 100, they are about
£60 per thousand if you buy lots of them.

You want the red or better the black ones, but the black ones can be
more expensive and harder to get.

Some somewhat dangerous examples of use (cavers are nuts anyway):

It is possible to use them in a safer manner!!!

8mm drill :)

Post by Richard Smith

Post by Richard Smith
Cavers use...

Can visualise that - crawling along in a tiny space, having to carry
any kit in such journey, and no space to swing a sledgehammer if you
come to an obstruction...

Just "crawling along in a tiny space" is bad enough ...


Peter Fairbrother

[Richard Smith]

Post by Peter Fairbrother
Capping or Hilti capping uses Hilti nail gun gun cartridges, which you
...
https://www.ebay.co.uk/itm/225952485669 at £15 for 100, they are about
£60 per thousand if you buy lots of them.
You want the red or better the black ones, but the black ones can be
more expensive and harder to get.
http://youtu.be/OuPozHyKEKg
http://youtu.be/XjgWA8v52Go
...

Thanks.
I visualise they are frequently hopping around in various types of pain.

A young fellow who has come along as another volunteer at "our" mine has
what I take to be identically the same drill as second caver type is
using.

I've got the masonry-drill in mine, while he has the pick chisel in his
- on non-rotative obviously.
So we alternate machines. Drilling and "feather'ing" until cracks, then
swapping over to use the pick to open-up the rock releasing the
"feathers" and completing the split / separation. While the other
drills.

Because dust accumulates in the air in the mine, do the drilling under
water flood. Always ejecting slurry.

Do have to find a way to wash away the slurry, as the "10mm" feathers
are a tight fit in the 12mm hole. Plus want slippery metal-to-metal
contact, lubed with oil-graphite spray - don't want abrasive paste of
the slurry in the wedge-to-feathers contact, increasing wear and making
friction.

Not found answer to that yet.
Might make say 11mm dia bit of polymer rod, with small central hole you
inject water down some way. Hopefully efficiently sluice-out the
slurry from bottom to exit of hole.

"Capping" looks interesting, but if it's anything like in those videos,
is not going to be happening at "our" mine.

As I'd like to go for a shot-firer's ticket, might be best to come over
as measured in what I do.

So likely stay with wedges.

Thanks.
At least I have been amused.
Second guy could have been able to sing very high notes if rocks had
gone in another direction - as other comment.


Regards,
Rich

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

Do have to find a way to wash away the slurry, as the "10mm" feathers
are a tight fit in the 12mm hole. Plus want slippery metal-to-metal
contact, lubed with oil-graphite spray - don't want abrasive paste of
the slurry in the wedge-to-feathers contact, increasing wear and making
friction.

Not found answer to that yet.
Might make say 11mm dia bit of polymer rod, with small central hole you
inject water down some way. Hopefully efficiently sluice-out the
slurry from bottom to exit of hole.

Regards,
Rich
------------------------

I drilled dry, outdoors, and removed the dust by blowing into a 3/8"
flexible PVC tube with a 1/8" (3mm) nozzle, that I had made to restart
smouldering stove fires. The tube is long enough to keep my face away from
the dust and the fire. Drilling a convergent nozzle hole with a tapered wood
screw bit like this improves the discharge coefficient and lets you easily
test and increase the hole size. A smaller hole worked well, 1/8" empties my
lungs at a sustainable breathing rate.
https://www.amazon.com/Speed-Steel-Taper-Point-Drill/dp/B0057H22AW

Lacking a lathe, oversized aluminium rod can be reduced to a press fit in
the tubing by chucking it in a drill press and filing.

For a different project I fitted a 1/8" pipe thread to push-in tubing
adapter into the cap of a carbonated drink bottle. The combination might let
you wash out the hole with water from your squeeze bottle.

If you're into mild mischief a cap with a well centered hole (lathe) turns
the bottle into a water + compressed air rocket. I was experimenting with
the rocket remotely pressurized and self-releasing to see how much air it
would hold before bursting. Alternately the bottle can be overfilled with
water so it lifts off slowly and sprays all around as it wanders before
accelerating upward. A 6mm hole and 1/4th water is a good start.

Aluminium, brass and plastic parts like these can be made on a small
inexpensive hobby lathe. When I tried making larger steel parts I realized I
needed an industrial lathe, plus a vertical knee mill and a bandsaw. The 10"
(diameter) South Bend has been more than enough for most hobby and lab
prototyping projects, their 9" model was very popular. I'm redesigning the
blade guide roller assembly for my sawmill and turning or milling each part
to the CAD drawing as I progress, to aid and confirm the 3D fitup.

This CAD program is for printed circuit layout. I found it could draw
machined RF-tight enclosures for the microwave circuit boards as well,
though not correctly export as .DXF, the parts were machined from paper
prints. Is there a free CAD for 3D printing that keeps the program and
designs on an isolated computer instead of the cloud?

[Peter Fairbrother]

On 08/04/2024 00:46, Jim Wilkins wrote:
Is there a free CAD for 3D printing that keeps the program and

Post by Jim Wilkins
designs on an isolated computer instead of the cloud?

FreeCAD?

I use it all the time with .stl's and Cura slicer for ffm 3D, but it
does .step's and .dxf's as well.

Not great, but it is free. Fairly comprehensive, but a bit buggy, also
can crash so backup often. Supposed to be open-source, but some parts
aren't. Bit of a Curate's egg, good in parts but some parts are... not
good. Learning curve is steep-ish.

Default is local storage only.


Peter Fairbrother

[Jim Wilkins]

"Peter Fairbrother" wrote in message news:uuvdfo$333do$***@dont-email.me...

On 08/04/2024 00:46, Jim Wilkins wrote:
Is there a free CAD for 3D printing that keeps the program and

Post by Jim Wilkins
designs on an isolated computer instead of the cloud?

FreeCAD?

I use it all the time with .stl's and Cura slicer for ffm 3D, but it
does .step's and .dxf's as well.

Not great, but it is free. Fairly comprehensive, but a bit buggy, also
can crash so backup often. Supposed to be open-source, but some parts
aren't. Bit of a Curate's egg, good in parts but some parts are... not
good. Learning curve is steep-ish.

Default is local storage only.


Peter Fairbrother

----------------------------
Thanks, just downloaded it.

[Richard Smith]

Post by Richard Smith
Do have to find a way to wash away the slurry, as the "10mm" feathers
are a tight fit in the 12mm hole. Plus want slippery metal-to-metal
contact, lubed with oil-graphite spray - don't want abrasive paste of
the slurry in the wedge-to-feathers contact, increasing wear and making
friction.
...
------------------------
I drilled dry, outdoors, and removed the dust by blowing into a 3/8"
flexible PVC tube with a 1/8" (3mm) nozzle, that I had made to restart
smouldering stove fires. The tube is long enough to keep my face away
from the dust ...

Down the mine / in the mine...
The dust would hang in the air and everyone would breath it in.
Turning up your miner's lamp to full-brightness you can see glinting
tiny particles in the air - highly likely to be silicate. Just a test
little bit of drilling before everyone heading to surface. Not even
"production-level" amounts of drilling.
Absolutely cannot be.

Water flood (actually not a lot of water) to get a slurry.
Nothing glinting in the air by same test of miner's lamp at
full-brightness shining along the level so bright in the beam and no
reflecting-back light (lost a hundred metres and more away).
Completely effective in that regard.

But then yes how to get the adherent slurry out of the drilled
sockets...

[Jim Wilkins]

... pipe to hose adapter...

Down the mine / in the mine...
The dust would hang in the air and everyone would breath it in.
Turning up your miner's lamp to full-brightness you can see glinting
tiny particles in the air - highly likely to be silicate. Just a test
little bit of drilling before everyone heading to surface. Not even
"production-level" amounts of drilling.
Absolutely cannot be.

Water flood (actually not a lot of water) to get a slurry.
Nothing glinting in the air by same test of miner's lamp at
full-brightness shining along the level so bright in the beam and no
reflecting-back light (lost a hundred metres and more away).
Completely effective in that regard.

But then yes how to get the adherent slurry out of the drilled
sockets...

-------------------------

The brief but important part of my post was how to connect flexible rubber
or vinyl tubing to a drink bottle cap. In the USA threaded electric lamp
tubing has the non-tapered "IPS, Iron Pipe Straight" version of 1/8" pipe
thread, and brass lock nuts for lamps could reinforce the pipe thread joint
into the bottle cap.
http://www.lampshademaker.com/lamp_pipe_size_chart.htm

The flexible tubing connection could be a barbed spigot, compression with a
plastic sleeve, or a push to disconnect fitting. Flare might even work, I
haven't tried it on vinyl tubing.

IPS female fits but usually requires a rubber washer to seal on NPT (pipe)
male. Sink spray and shower head hoses may use it. The high pressure
hydraulic equivalent is named "swivel" and seals with a metal cone.

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

But then yes how to get the adherent slurry out of the drilled
sockets...

-------------------------

https://www.bbqboxuk.com/products/2-piece-turkey-baster-set
With an extension hose, cut diagonally on the pickup end.

[Richard Smith]

Post by Richard Smith
then yes how to get the adherent slurry out of the drilled
sockets...
-------------------------
https://www.bbqboxuk.com/products/2-piece-turkey-baster-set With an
extension hose, cut diagonally on the pickup end.

Thanks - I was trying to get ideas for this.

[Jim Wilkins]

Post by Richard Smith
then yes how to get the adherent slurry out of the drilled
sockets...
-------------------------
https://www.bbqboxuk.com/products/2-piece-turkey-baster-set With an
extension hose, cut diagonally on the pickup end.

Thanks - I was trying to get ideas for this.

---------------------------
The clear ones appear to be styrene, gasoline attacks them and they can
crack if abused. The somewhat frosted ones may be polyethylene or
polypropylene which is more durable and chemical resistant. A reinforcing
swelling at the tip helps retain the extension tubing. If too small, vinyl
tubing can be expanded by warming and stretching with needle-nose pliers.

Snag-free tubing clamping:
https://www.netknots.com/rope_knots/common-whipping

The cut ends can be pushed in to disappear. I suspect the Gordian Knot used
the same trick.

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

The question:

How would you go about producting wedges about 2mm to 3mm thinner than
the current ones?

Doing something to the current wedges would be okay.

Making them anew with something like forging could be a good project.
If so what steel would you use? AISI1075? (C-Mn; 0.75%C). If so -
"spring-temper"?

We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).

Always appreciated the range of knowledge here.

Regards,
Rich Smith

------------------------------

https://sheffieldgaugeplate.co.uk/blog/en8-vs-en9/

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

Making them anew with something like forging could be a good project.
-----------------------------

I'm only a novice blacksmith. Much of my practice was in drawing out a round
bar into a long tapered one of square cross section. The idea is to compress
the whole width of the bar under the hammer, since flattening a solid round
section applies internal tension to areas protruding outside the hammer
strike that can open voids. If desired it can be rounded after tapering.

As thinning an area widens as well as lengthening it, the thickness had to
be reduced gradually and evenly on all sides, keeping a square cross section
and immediately correcting bending, twisting and the tendency to become a
rhombus. For me lengthening with a cross peen hammer caused more trouble
than it was worth.

The height of the anvil top affects how squarely you can consistently hit.
My anvil is too light for serious forging which I can't and don't need to do
anyway so I raised it to a more convenient bench height for less strenuous
work on sheet metal etc. It cured the temptation to hammer on the milling
machine table.

For a wedge my guess, based on pre-curving a single edged froe blade to end
up straight, is that the blank might have to be started with a square taper
before converting to a parallel sided wedge. Undoubtedly a real smith could
tell you more. Modeling clay is said to be good to practice with.

The wedge can be cut/broken from the bar by notching it all around on a
chisel standing upright in the square (Hardy) hole. The instructor was
amazed at how square and even the tenon on my attempt was, until I told him
I had used my milling machine. They have an ethic of using only traditional
methods, which is fine for artistic work but not the machine parts I wanted.

It was remarkable how many shapes the smith could form with only a hammer
and anvil. I didn't progress past drawing out a taper, stepping down a
shoulder and bending over the horn. My efforts at twisting can't be called
progress, or art.

[Leon Fisk]

On Thu, 28 Mar 2024 17:53:45 +0000

Post by Richard Smith
How would you go about producting wedges about 2mm to 3mm thinner than
the current ones?
Doing something to the current wedges would be okay.

These aren't that expensive via Amazon:

https://www.amazon.co.uk/s?k=rock+splitting+wedges&ref=nb_sb_ss_ts-doa-p_2_8

Think I'd try clamping the pieces together and have at them with a
small angle grinder. Doubt if the outside being slightly rough would
hurt anything. Whether losing a couple millimeters on the outside and
probably some of the wedge causes them to wear out faster is the
question...

[Richard Smith]

Hi all.
Thanks for helping me develop thoughts.
To expense-wise putting the horse before the cart, maybe get hold of
some spring steel from eg. a truck, and either grind direct to shape or
forge and retreat.

Also, got some more wedges on-order, so might take 3 wedges and try
grinding a millimetre off either side of the wedge and see how they
perform.
Am used to using an angle-grinder.
Good strategy for removing a fixed amount can be to gash with a slitting
disk to depth you want to remove (in this case 1mm) - you can measure
accurately how deep a gash is - then generally grind until you just
remove the gashes.
Knowing where you are going with it, you cna control grinding rates and
temperatures - don't change the material.

Smooth - finish by gliding on the side of the disk... Well used to
doing this to make tight joints / flat surfaces.

Will see where all this takes me.

[Leon Fisk]

On Sun, 31 Mar 2024 22:30:05 +0100
Richard Smith <***@void.com> wrote:

<snip>

Post by Richard Smith
Also, got some more wedges on-order, so might take 3 wedges and try
grinding a millimetre off either side of the wedge and see how they
perform.
Am used to using an angle-grinder.
Good strategy for removing a fixed amount can be to gash with a slitting
disk to depth you want to remove (in this case 1mm) - you can measure
accurately how deep a gash is - then generally grind until you just
remove the gashes.

It would be helpful if you had a way to chuck and spin them from the
end providing they spun somewhat true. Then you could just work the
angle grinder back and forth along them as they turned. Yeah, I know...
probably not feasible 🙄

Having the desired hole size in a piece of wood laid nearby and testing
off/on would likely be easiest...

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

Hi all.
Thanks for helping me develop thoughts.
To expense-wise putting the horse before the cart, maybe get hold of
some spring steel from eg. a truck, and either grind direct to shape or
forge and retreat.

----------------------------------------

The problem with leaf springs is thickness, plus used ones may have cracks.
You could anneal it and saw out the wedges, or just plasma cut them, but
assembling a stack could be difficult. Brazing might work as long as
hardening didn't melt it.
https://knifesteelnerds.com/2019/04/01/how-to-heat-treat-5160/

[Richard Smith]

Post by Richard Smith
Hello all
"feathers" work well for splitting boulders so can be removed as
handleable rocks.
Lots of videos online eg. YouTube how to use them.
http://www.weldsmith.co.uk/tech/minerals/pics/240314_feathers_holes.jpg
from page
http://www.weldsmith.co.uk/tech/minerals/240314_rocksplit/240314_rocksplit_drill_feathers.html
"Rock-split granite with "cordless" SDS drill and "feathers""
They work really well.
But these "10mm" feathers need a 14mm-dia socket.
The wedge is visibly oversized=overthickness for the feathers.
Saving just two mm of thickness would surely enable using a 12mm
socket. Useful saving on drilling (14mm -> 12mm)
(/ (expt 12 2) (float (expt 14 2))) ;; 0.7346938775510204
73% of vol drilled - and the impact is concentrated on the smaller
cutting tip.
How would you go about producting wedges about 2mm to 3mm thinner than
the current ones?
Doing something to the current wedges would be okay.
Making them anew with something like forging could be a good project.
If so what steel would you use? AISI1075? (C-Mn; 0.75%C). If so -
"spring-temper"?
We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).
Always appreciated the range of knowledge here.
Regards,
Rich Smith

Follow-up, for what it's worth...

This is about my "10mm" (~ 3/8inch) rock-splitting feathers.

As-supplied, they need a 14mm diameter socket to fit-in in the rock you
want to split.

I ground three wedges thinner so they will fit in a 12mm socket.
Which I have been the "feathers" I have used for breaking up "rocks"
lying-about in the hobby mine.
The request is : preferably don't send rocks in the skip up the haulage
shaft which are much bigger than a loaf of bread.

So I have been rapidly drilling-in a couple or three sockets in stones
and splitting them "rapidly" - skip-loads to surface (given our "mine"
is tiny and so is the skip in the haulage-shaft).

Recent finding for "boulders" which are bigger than two people could
carry...

You need the stiffness of the wedges in the feathers-and-wedge's
as-supplied.
So that was got right as-supplied.

My SDS "cordless" battery-powered drill is fast at 12mm but definitely
taking more than pro-rata longer at 14mm.
Mustn't make dust down in the mine, as the fine silica dust would
circulate around and be breathed-in by everyone.
So must drill under water-flood (keeps the drill cool, too).
Nett...

Go around your boulder with a pilot-drill size, doing the various planes
along which you intend to split it, then go around again with the 14mm
drill, then use the feathers lined along each plane to do the splitting.

Seems 7mm pilot-hole size would be ideal
* 6mm too small - the SDS cordless drill can "over-power" it into the
hard granite and a moment's inattention can have it red-hot then
destroyed.
* 8mm drills well but maybe unnecessarily large
Unfortunately (?) masonry drill sizes go in 2mm increments. So I have
to go with 8mm.

The one about water-flood - if the drilling is going at a good rate,
it takes less concentration and you can be happily holding the
water-bottle in the other hand, squeezing a fast fine jet through a
small hole in the lid which sprays onto the rotating drill at the point
it goes into the rock.

Yesterday a mining engineer and a civil engineer watched how I split a
boulder...
Seem to be doing something right...

Thanks for the help the nearly 3 months ago when I was trying for find
my way with this.

Rich Smith

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

Yesterday a mining engineer and a civil engineer watched how I split a
boulder...
Seem to be doing something right...

-----------------------------
Can a new way to combine and use existing equipment be patented?

[Richard Smith]

Patent no way - I spotted that cordless tool battery powers now enable
drilling sockets for feathers&wedge. Everything familiar already - it's
just reaching a "cross-over point" where becomes economic.

[Jim Wilkins]

"Richard Smith" wrote in message news:***@void.com...

Patent no way - I spotted that cordless tool battery powers now enable
drilling sockets for feathers&wedge. Everything familiar already - it's
just reaching a "cross-over point" where becomes economic.

--------------------------------------
I asked because my hoisting tripod top connection is standard hardware store
material arranged in a way I haven't found elsewhere, that leaves the legs
free to move in all directions when unloaded but locks up rigid under load.
I think the upper leg attachment counts nearly as pins equally loaded at
both ends but due to the odd geometry the calculation is beyond me. The foot
end is almost a ball joint, again using standard material.

Recently I bought a 2000Kg crane scale that will let me proof test them
above the 1000Kg (2204 Lbs) that they support with no sign of stress.
It cost $90 and matches the 1000Kg scale within <5 Lbs at 1500 Lbs, so far.

[David Billington]

Post by Richard Smith

Post by Richard Smith
Hello all
"feathers" work well for splitting boulders so can be removed as
handleable rocks.
Lots of videos online eg. YouTube how to use them.
http://www.weldsmith.co.uk/tech/minerals/pics/240314_feathers_holes.jpg
from page
http://www.weldsmith.co.uk/tech/minerals/240314_rocksplit/240314_rocksplit_drill_feathers.html
"Rock-split granite with "cordless" SDS drill and "feathers""
They work really well.
But these "10mm" feathers need a 14mm-dia socket.
The wedge is visibly oversized=overthickness for the feathers.
Saving just two mm of thickness would surely enable using a 12mm
socket. Useful saving on drilling (14mm -> 12mm)
(/ (expt 12 2) (float (expt 14 2))) ;; 0.7346938775510204
73% of vol drilled - and the impact is concentrated on the smaller
cutting tip.
How would you go about producting wedges about 2mm to 3mm thinner than
the current ones?
Doing something to the current wedges would be okay.
Making them anew with something like forging could be a good project.
If so what steel would you use? AISI1075? (C-Mn; 0.75%C). If so -
"spring-temper"?
We have something called "silver steel" which is "(centreless-?) ground
0.8%C steel" (ie. right on the eutectoid).
Always appreciated the range of knowledge here.
Regards,
Rich Smith

Follow-up, for what it's worth...
This is about my "10mm" (~ 3/8inch) rock-splitting feathers.
As-supplied, they need a 14mm diameter socket to fit-in in the rock you
want to split.
I ground three wedges thinner so they will fit in a 12mm socket.
Which I have been the "feathers" I have used for breaking up "rocks"
lying-about in the hobby mine.
The request is : preferably don't send rocks in the skip up the haulage
shaft which are much bigger than a loaf of bread.
So I have been rapidly drilling-in a couple or three sockets in stones
and splitting them "rapidly" - skip-loads to surface (given our "mine"
is tiny and so is the skip in the haulage-shaft).
Recent finding for "boulders" which are bigger than two people could
carry...
You need the stiffness of the wedges in the feathers-and-wedge's
as-supplied.
So that was got right as-supplied.
My SDS "cordless" battery-powered drill is fast at 12mm but definitely
taking more than pro-rata longer at 14mm.
Mustn't make dust down in the mine, as the fine silica dust would
circulate around and be breathed-in by everyone.
So must drill under water-flood (keeps the drill cool, too).
Nett...
Go around your boulder with a pilot-drill size, doing the various planes
along which you intend to split it, then go around again with the 14mm
drill, then use the feathers lined along each plane to do the splitting.
Seems 7mm pilot-hole size would be ideal
* 6mm too small - the SDS cordless drill can "over-power" it into the
hard granite and a moment's inattention can have it red-hot then
destroyed.
* 8mm drills well but maybe unnecessarily large
Unfortunately (?) masonry drill sizes go in 2mm increments. So I have
to go with 8mm.
The one about water-flood - if the drilling is going at a good rate,
it takes less concentration and you can be happily holding the
water-bottle in the other hand, squeezing a fast fine jet through a
small hole in the lid which sprays onto the rotating drill at the point
it goes into the rock.
Yesterday a mining engineer and a civil engineer watched how I split a
boulder...
Seem to be doing something right...
Thanks for the help the nearly 3 months ago when I was trying for find
my way with this.
Rich Smith

As all the masonry bits I've ever had have the TC insert sticking out
the sides of the shank I was going to suggest narrowing an 8mm bit to
nearer 7mm with a diamond or green wheel, my 8mm bit measures 8.25mm
across the TC insert and the shank is 7.1mm. That being said a quick
search for 7mm masonry bits turns up plenty of them and they seem to be
readily available from many sources.

[Jim Wilkins]

Post by Richard Smith
http://www.weldsmith.co.uk/tech/minerals/pics/240314_feathers_holes.jpg

-------------------------
Your wedges are much larger compared to the shims/feathers than mine.
Perhaps the seller mixed two sizes?
https://trowandholden.com/wedge-shim-sets.html

[Jim Wilkins]

Post by Jim Wilkins

Post by Richard Smith
http://www.weldsmith.co.uk/tech/minerals/pics/240314_feathers_holes.jpg

Your wedges are much larger compared to the shims/feathers than mine.
Perhaps the seller mixed two sizes?
https://trowandholden.com/wedge-shim-sets.html

-------------------------
The Amazon / Acofuns wedges are shown to be 10mm wide for the 10mm nominal
size.
https://www.amazon.co.uk/Acofuns-Wedges-Feather-Concrete-Splitter/dp/B0B5PHTNJW

My kind of tool:
"Finally, beat with a hammer."

[Richard Smith]

Post by Jim Wilkins
The Amazon / Acofuns wedges are shown to be 10mm wide for the 10mm
nominal size.
https://www.amazon.co.uk/Acofuns-Wedges-Feather-Concrete-Splitter/dp/B0B5PHTNJW

Mine look identical as-arrived.
My guess - same manufacturer - same "model".
If so, they fit in a 14mm dia. socket.

[Jim Wilkins]

Post by Jim Wilkins
The Amazon / Acofuns wedges are shown to be 10mm wide for the 10mm
nominal size.
https://www.amazon.co.uk/Acofuns-Wedges-Feather-Concrete-Splitter/dp/B0B5PHTNJW

Mine look identical as-arrived.
My guess - same manufacturer - same "model".
If so, they fit in a 14mm dia. socket.

-----------------------------------

Can you start the wedge at all between the feathers in a 10mm hole?

Mine fit the nominal size hole with the wedge somewhat less than half way
in. It scraped and gouged the feathers until I rounded and smoothed the
leading edge corners of the wedges. I straighten the feathers on the anvil
after use. Next time I might rub bar soap on them as a dry lube.

[Richard Smith]

Post by Richard Smith

Post by Jim Wilkins
The Amazon / Acofuns wedges are shown to be 10mm wide for the 10mm
nominal size.
https://www.amazon.co.uk/Acofuns-Wedges-Feather-Concrete-Splitter/dp/B0B5PHTNJW

Mine look identical as-arrived.
My guess - same manufacturer - same "model".
If so, they fit in a 14mm dia. socket.
-----------------------------------
Can you start the wedge at all between the feathers in a 10mm hole?
Mine fit the nominal size hole with the wedge somewhat less than half
way in. It scraped and gouged the feathers until I rounded and
smoothed the leading edge corners of the wedges. I straighten the
feathers on the anvil after use. Next time I might rub bar soap on
them as a dry lube.

Fit - socket size in boulder - nominal 10mm feathers-and-wedge...

Can't remember.
I think the pair of "feathers" alone would fit in a 10mm hole.

I think if you tried pulling the outer ends of the feathers apart,
splayed, you could get the tip of the wedge in and start hammering, with
result that the feathers would bend, splay and ruin the feathers - the
wedge never getting under the level of the rock.

I think it's a "no way". Certainly it isn't useful.

12mm socket - the feathers fit in well and the wedge slimmed 2mm goes in
- all nice. As I found - as boulders get bigger, the thinned wedge
doesn't seem up to transmitting the blows of the lump-hammer..
The three thinned wedges - for small rocks lying-around one person can
go along drilling sockets and a following person can split with the
feathers. Can move along quite quickly leaving nothing much bigger than
a loaf of bread.
No reason for more that three of these thinned wedges, as never need
more than a set of three feathers-and-wedge for rocks which only have to
be halved split into 3 or quartered into 4.

Long answer, and memory doesn't go back to that first time I drilled
with a 10mm drill expecting that to be the one needed.

I see the reason for the "10mm" (sic.) design. The stiff wedge protects
the thin feathers. With my experiences with this hard granite - I doubt
any smaller solution than the feathers fitting in a 14mm socket could
transmit the effect of a lump-hammer to split bigger boulders more than
two people could not carry. The feel as you go along the line of wedges
tapping them with the lumpy... Is all very taut...

[Richard Smith]

Yes - cannot buy from tool-store - but do seem to be offered online.
Even if could special-order in a good brand from a tool-store, not
enough boulders to dispose of to make it worth-while.