Clamps Marking Leather

[Munday]

For my first project I thought I’d make a simple folder-over knife sheath.  When I was forming it and clamped the edges with black spring clamps, I discovered some of the clamps left black marks on the leather.  I couldn’t remove the black marks so I dyed the leather.  I also discovered the clamps left dents in the leather and I don’t know if the dents can be fixed. 

I went ahead and stitched it together knowing I’d be doing it over (just to get some experience); the stitching didn’t go well either but I know more now.  

I wetted a scrap piece of leather to test the clamps. 

 

[chuck123wapati]

use contact cement. you can get weldwood brand at about any hardware store or walmart

Edited November 27, 2021 by chuck123wapati

[battlemunky]

Iron changes the composition of the leather chemically. I'm betting that the iron in the spring steel of those binder clips made it through to the leather and got you the black you see.

[tsunkasapa]

And your leather was far too wet if the clamps left those marks.

[Handstitched]

Yep, as @chuck123wapati said, contact adhesive. I've learnt my lesson when using those clamps. I only use them briefly just to hold the leather together while the adhesive sets, otherwise they will leave marks.They are an extra pair of hands in leather, but   I never keep them on for long lengths of time. Looks like your leather was a bit too wet. 

HS

[HandyDave]

When i do have to clamp something and leave it for a time. I put some scrap  strips of leather between my clamps and my finished piece. And i also have seen similar clamps that look rubber coated that might work better without the problem. The scrap leather under clamps also helps spread out the load enough to not indent if leather is a little wetterthen it needs to be.

[fredk]

I use either scraps of leather or pieces of lolly sticks between the bulldog clamps and the leather. Which I use depends on a: what come to hand or b: the shape of the glued line

Lolly sticks spread the clamping load better and leather will conform to a curve better

I've left things clamped up like this for days or weeks, not usually deliberately but because I've forgotten to finish the item or I've been waiting on something to finish it off

[Munday]

Thanks for the information.

[fredk]

You see your knife sheath there? If you clamp it up with lengths of lolly (popsicle?) stick along the shape you can get a nice sharp line along the blade edge

[jcuk]

These maybe of use to you also 18mm are available in some places. Things like that i usually lightly tack but each to their own.

https://www.artisanleathersupply.com/products/locking-pins

Hope this helps

JCUK