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Chiseling V-shape into jaws Q


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Hi folks! I've recently been attempting to make some it-but bolt tongs from blanks, and am having a lot of difficulty chiseling the v-shape into the jaws.

I've been trying to hold my tong blank in my approx 30lb antique leg vise, but as I hit my chisel, the blank slips down and pretty much out of the vise after just a few blows.  This means that my force isn't translating into effective chiseling.

I'm going to assume the old vise is probably just not up to holding as tight as needed and probably has been abused and may have some thread damage.  It was a freebie thrown in with some tools I bought and works pretty good for twisting.

So before I ruin my blanks trying something that might work poorly, I wanted to ask advise.  Here's a few possible solutions and want your feedback:

1) get a heavier, better shape vise. I don't have a source for one yet nor can I financially justify it now.

2) have a partner hold the heated blank on the anvil while I chisel.  The downside I see is that the curve of the blank is what contacts the anvil, not directly under the jaw, so I foresee some pretty bad bending while chiseling.  I could probably bend it back to shape, but my beginner skills may let me down.

3) cut a slot with a hack saw or angle grinder.  I assume this removes a lot more material than chiseling.  The blanks are pretty light so I dont know if the kerf from a cut is too much.

Are options 2 or 3 worth trying, or will it probably fail?

Let me know if you have any smart suggestions, I'm sure slipping work pieces in vises is not an issue I'm alone in experiencing.

Preemptive thank you!

 

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Peter:  When doing chisel work you want the target backed up by something solid.  In a vise, and I'm assuming that you are clamping the edge of the tong jaws and chiseling in the gap between the vise jaws, all you have is the friction and pressure of the vise jaws holding it in place against the force of chisel and the hammer blow.  The 2 forces are at 90 degrees to each other.  You have to have the force of the blow met with an opposite force of resistance in the opposite direction.

So, I suggest either hold the tong jaw up side down on the edge of the anvil with a helper or some sort of bracing supporting the rein of the tong half and then striking downward with the chisel above the part that is on the anvil or cut or file a groove cold..

I hope this helps.

"By hammer and hand all arts do stand."

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You could take a piece of heavy angle iron and upset one leg. Then forge the extra mass over so it’s flat on the inside of the angle. Finally, file the step good and square. Clamp this up with you blank and the step should support your blank. Just make sure the step is wide enough for support and high enough to hold the blank where you need it.

Of course, you could just hold it between you legs with a heavy set of locking pliers lock on just past the bit to let gravity help hold the blank vertical and work right at the anvils edge. (Selection cooling is very important with this approach if you’re using a gas forge!) 

David

Looks like irondragon types faster than me, and why didn’t I think of that? I’ve seen that video before...

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Hold the reins between your legs with the jaw bottom flat on your anvil face. Chisel in one hand, hammer in the other. Strike like George above says.

Welcome to the 21st century version of traditional blacksmithing.  ;)

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When I make bolt jaw tongs like that (as others have said) I do it at the anvil, heat the jaws up at the forge and attach a pair of C-clamp vise grips to the rounded section between the jaw and the boss. The extra weight helps to keep the jaw standing on end as I hold the reins between my legs. 

I didn't come up with this, Torbjörn Åhman demonstrates it in his video of making bolt jaw tongs.

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Or drop a hardy hole sized piece of stock in the hardy hole and clamp the rein to it and place a steel block the right size under the part you want to chisel.

I have a large C clamp that I use to fasten tooling mounted on angle iron to be used in the post vise to the side of the anvil to use it on the face.

Blacksmithing is a many-fold path!

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Peter,

One mental trap of blacksmithing is to think that all operations are best done hot with a hammer.  If you put a convenience bend in the tips, you can clamp the bit of the tongs such that you can use a hacksaw to perfectly center a cut along the length of the bit.  Once you've cut to the desired depth, you can heat the bit, and use a hardie to open the cut.  It takes a bit of patience, but you can also take a bit of square stock, and cut it corner to corner to make yourself a triangular prism with 45/45/ 90 degree corners.  Place the hypotenuse side on your anvil face, and use the 90 degree corner like it's an anvil "devil" against the aforementioned sawcut.  That will give you a perfectly formed 90 degree corner on the inside of your bit.

Depending on the size of the bit, and the state of your anvil corners, you might be able to use an anvil corner to open the sawcut and form the jaw as well.  The saw cut creates a path of least resistance which will help to keep everything equal on both sides.

 

 

 

 

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