Diamond chisel - each side separately or through both?

[livewire516]

I've seen/read instruction to use a diamond chisel much like a pricking iron: chisel each piece separately, then join them together for stitching.

I've also been instructed to glue both pieces of leather together, then strike the diamond chisel through both pieces at once.

I'm left with the impression that the first technique will result in a finer end product, while the latter technique is easier. That being said, I'm a novice and I'd like the community's input as to which method they use, and why.  Are their certain use-cases where one is necessary? (ex. when both faces are effectively show faces, I'd imagine you ought to use the first technique).

I'm looking forward to any guidance on the matter.

[TargetRockLeather]

It depends on what the total thickness is with the pieces glued together.

If the chisel will go through all of the pieces at once, then glue them together and do it that way.

If the combined pieces are thicker than the chisel will penetrate, then you'll have to chisel them separately.

In my opinion, going through all of the layers at once will give better accuracy. That's IF the chisel will go through all at once. Chiseling the pieces separately and then getting all the holes to line up when you put it all together can be somewhat challenging. But certainly doable. There are several ways to accomplish that.

[TSes]

You can't use a chisel on both good sides and put them together with both good sides out. The chisel holes will be oriented in opposite directions. Best to do both layers at once.

[GatoGordo]

I believe that you have it correct. Since the holes are at an angle, when the holes are made through both sides at once the slant will be correct for the front side, but incorrect for the back. This results in a great looking front, but a not so great looking back. If the holes are made in each side separately, then both front and back have holes at the correct angle for their side and stitching on both front and back will look good. You can see an example of this in Nigel Armitage's video on YouTube where he reviews the Crimson Hides pricking irons. At the 27 minute mark, he makes the holes in both pieces separately and then puts them together and stitches. He then challenges the viewer to decide which is the front and which is the back.

Of course, if the back is not going to be seen there is no need to go through this extra effort.

[Danne]

2 hours ago, TSes said:

You can't use a chisel on both good sides and put them together with both good sides out. The chisel holes will be oriented in opposite directions. Best to do both layers at once.

 

Yes, you can, with thicker leather it's no reason to do like this because it's possible to get a nice stitch/slant on both sides if you cast the thread. When you stitch really thin edges like around 2mm or less in total thickness it's very hard to get a nice slant on both sides unless you use very thin thread, or a very good technique and/or combination of leather stiffness. In this case, you can punch from both sides (with the same irons) and stitch without cast and get a nice slant on both sides.

 

Examples of crafters who use this technique are Chestermox and Shiang Lin. Here you have an example from Chestermox. It's not easy since you have to punch your holes at the correct distance and align everything really good.

 

 

[Hardrada]

You can also buy "reverse" pricking irons/chisels. Of course, that doubles the cost of that part of the stitching equipment.

Edited November 8, 2019 by Hardrada

[livewire516]

Thanks for everyone sharing their thought process. Yeah, I'm finding the difficulty of matching sides at the moment with a practice project. It was helpful to spot check every so often with an awl, but as mentioned in a Nigel Armitage video, when you chisel each side separately, you really only have the very center of the hole so it's a little harder for the harness needle to find its way through.

[zuludog]

I usually glue everything together before I use a stitching chisel

If the combined thickness is still thin enough for the chisel to go through all the layers, no problem

If the combined thickness is too much for the chisel to penetrate all the layers I follow up and complete them with an awl, using the partly formed holes as a guide

[TargetRockLeather]

I guess I misunderstood the question when I replied the first time. I assumed he meant going through each layer separately in the same direction, not from the front and then from the back. I made that mistake once and was not happy with the result, so I would never use that technique again.

[chuck123wapati]

I do the top piece first, then clamp my pieces together and do the first one through both pieces or all three if its a holster or sheath then I have a starting point for lining up the  chisel holes, then I can  do the two other pieces and I can do them from the rough side so all the holes are at the correct angle. Then I use some small brass nails and put one every inch or two through the holes to line them up when gluing the pieces together to align them. After that I remove the nails go through them with an awl then sew em up. I do mostly holsters and sheaths in heavy weight leathers. if its thin leather I glue and do both sides at once.