How to account for a circumference increase for bracelets or collars when layering or padding leather?

[Dwight]

6 hours ago, TomE said:

SO when you use a shorter piece of padding, will that prevent creasing when the final piece is straightened? 

I'm not sure what you mean by creasing . . . of you are making nose pieces . . . collars . . . etc . . . they are made to be round or rounded . . . they are not made to be straightened.

The whole function of the technique I told you about it to make sure the pieces fit . . . it stays rounded . . . and it does not wrinkle on the inside most piece.

May God bless,

Dwight

[SUP]

49 minutes ago, Dwight said:

I'm not sure what you mean by creasing

See, any time 2 layers of leather are stuck together, there is potential for creasing on one side or the other, depending on how the leather is folded, especially if the leather is not firm.

 e.g.  I plan to use some filigree stamps on a bracelet, with  filigreed leather on the uppermost surface, the colored lining and the inner lining which will be the same as the filigreed leather but without filigree. But it is soft leather, not firm leather and it will not be molded into a specific shape. I can stick this flat, in which case, when I curve the bracelet to wear it around my wrist, will not the innermost layer crease?

 

[TomE]

3 hours ago, Dwight said:

I'm not sure what you mean by creasing . . . of you are making nose pieces . . . collars . . . etc . . . they are made to be round or rounded . . . they are not made to be straightened.

The whole function of the technique I told you about it to make sure the pieces fit . . . it stays rounded . . . and it does not wrinkle on the inside most piece.

May God bless,

Dwight

I think @SUP was commenting about creasing and I quoted her.  I make padded straps flat and they mold to a round shape with use.  Wrinkles and creases aren't an issue in my experience.  It would be difficult for me to hand sew them when curved because the jaws of my stitching horse are flat. Here's a noseband that is constructed of 2 layers of 9 oz leather and a neoprene pad wrapped in chrome tanned leather.  The 9 oz pieces are skived on the edges, shaped in a rounding block to create the swell, then glued and sewn together with the padding while flat.  The noseband readily shapes around a horse's nose.  You can see a few wrinkles in the pad but those smooth out with use and are of no concern to the clients I make bridles for. 

Regarding my original comment on this post, I don't have a wood shop but I do have a calculator on my phone.  I had wondered if padding a strap changed the measured size and the answer is -- not much but you can make a small allowance for it, if desired.

 

 

[SUP]

50 minutes ago, TomE said:

Wrinkles and creases aren't an issue in my experience.  It would be difficult for me to hand sew them when curved because the jaws of my stitching horse are flat. Here's a noseband that is constructed of 2 layers of 9 oz leather and a neoprene pad wrapped in chrome tanned leather.

I think that maybe the 9oz. leather does not crease - too thick to do that. When I make bracelets or straps for bags, it is thinner leather and that is why I probably face that issue.  And I agree, stitching horses have jaws that hold the leather flat. I wonder if we get curved ones. It would be of so much of help to all of you who sew larger items in different shapes.

Maybe someone with expertise in woodworking will come up with one. 

[Haraldsson]

Run the leather upright through the jaws. That way the jaws are holding onto a shorter bit of the curve. 

This pony's clamp-face is almost square, mine is 3 inches long but only has an inch tall surface. If you run the strap vertically, or at an angle, you can glue the straps together as both Dwight:

On 3/4/2024 at 5:20 AM, Dwight said:

Cut the filler . . . lay it around the piece . . . measure it . . . cut the top piece . . . glue em together around your circle.

and TomE did...

On 3/4/2024 at 5:46 PM, TomE said:

skived on the edges, shaped in a rounding block to create the swell 

And the pony wouldn't (shouldn't?) put undue pressure to push the strap flat again.

At least, I think that is what TomE was getting at...

I am stealing Dwight's method for my next gunbelt. I'm happy as a clam to find him still here after all this time! I last poked around here about 5-7 years ago; I'm not good with the passage of years.

[Dwight]

1 hour ago, Haraldsson said:

 

I am stealing Dwight's method for my next gunbelt. I'm happy as a clam to find him still here after all this time! I last poked around here about 5-7 years ago; I'm not good with the passage of years.

Yep . . . still here . . . glad to have ya back . . . 

May God bless,

Dwight

[Sarina]

I didn't realize I had notifications turned off for this post.

@TomE
Thanks for the detailed explanation! I think that formula makes sense, that's generally what I've been using. Your formula says, make everything flat, you just want to ensure that when it's formed into a circle that the innermost part of the circle is the circumference you expect. And the formula does just that. But perhaps my leather isn't quite as stretchy since when I try to form it into a circle it has a hard time actually forming a circle, especially if I have hardware like a rivet connecting two layers.

@Dwight

Your explanation makes sense as well, seems it's the opposite of TomE's explanation. You are making the leather as a full circle to begin with, so the stretching would happen when it's formed flat. Although how do you do things like punch holes for rivets or stitching and such when the leather is formed into a circle?

I think my goal is to be somewhere in the middle of the two solutions, so the leather stretches out just as much being flat as it does formed into a circle, but at rest it's concaved. But I still run into the same problem of how I can punch holes in the leather and have them line up,  since the leather needs to be flat to punch holes in it.

Edit: Actually the more I think about it the more I realize that there can't be an exact formula and that the way Dwight says is the only way to get it exact. Depending on the firmness and thickness of the leather, when you bend it into a circle the circumference of the inner part shrinks as it gets squished but also the circumference of the outer part grows some as it stretches. The exact amount depends on the type of leather and how big the circle is, so you can't make a formula that calculates it exactly.

Edited March 21, 2024 by Sarina
Realized why you can't use a formula to be exact

[Dwight]

3 hours ago, Sarina said:

I

Edit: Actually the more I think about it the more I realize that there can't be an exact formula and that the way Dwight says is the only way to get it exact. Depending on the firmness and thickness of the leather, when you bend it into a circle the circumference of the inner part shrinks as it gets squished but also the circumference of the outer part grows some as it stretches. The exact amount depends on the type of leather and how big the circle is, so you can't make a formula that calculates it exactly.

Actually, Sarina . . . I would only do that for a circle that I knew would be say 14 to 18 inches in diameter . . . or less . . . and only if I knew that the wrinkles on the inside would be a problem for the user or wearer.

For example . . . if my customer wanted a "stuffed" nose piece on a bridle or halter . . . a showy piece . . . I would get the measurement from the horse . . . make a round piece that width and that diameter . . . because I know the nose of a horse is tender . . . and if I made the piece and there were several large wrinkles inside it . . . they could rub and irritate the animal . . . which I would never allow if at all possible.  I'm a horse lover guy.  It would probably be less of a problem for a collar for a small dog . . . but in that case . . . it would be an ugly and "not professional" looking product . . . so again I'd make the model . . . so my finished product looked really nice if at all possible.

I have access to power tools and lumber . . . so for me to make a circle that is 13 inches in diameter is a piece of cake . . . taking me all of 25 to 30 minutes . . . I would staple or otherwise fasten the inslde piece of leather to the wood model . . . form the rest of the pieces . . . and then using an awl . . . punch thru the leather . . . into the wood . . . for the stitching.  

Once the pieces are made  . . .  I then glue them together with Weldwood contact cement . . . and they are easily stitched using my Cowboy 4500 or in some cases . . .  sewing it by hand . . . with a stitching pony.

For rivets . . . I just do the same thing . . . punch thru the leather into the wood . . . and not worry about it . . . I've done it many times.

Not being able to do it any other way . . . I find that "necessity is the mother of invention" . . . and needing it done makes me invent a way to do it.

May God bless,

Dwight

[TomE]

11 hours ago, Sarina said:

I didn't realize I had notifications turned off for this post.

@TomE
Thanks for the detailed explanation! I think that formula makes sense, that's generally what I've been using. Your formula says, make everything flat, you just want to ensure that when it's formed into a circle that the innermost part of the circle is the circumference you expect. And the formula does just that. But perhaps my leather isn't quite as stretchy since when I try to form it into a circle it has a hard time actually forming a circle, especially if I have hardware like a rivet connecting two layers.

@Dwight

Your explanation makes sense as well, seems it's the opposite of TomE's explanation. You are making the leather as a full circle to begin with, so the stretching would happen when it's formed flat. Although how do you do things like punch holes for rivets or stitching and such when the leather is formed into a circle?

I think my goal is to be somewhere in the middle of the two solutions, so the leather stretches out just as much being flat as it does formed into a circle, but at rest it's concaved. But I still run into the same problem of how I can punch holes in the leather and have them line up,  since the leather needs to be flat to punch holes in it.

Edit: Actually the more I think about it the more I realize that there can't be an exact formula and that the way Dwight says is the only way to get it exact. Depending on the firmness and thickness of the leather, when you bend it into a circle the circumference of the inner part shrinks as it gets squished but also the circumference of the outer part grows some as it stretches. The exact amount depends on the type of leather and how big the circle is, so you can't make a formula that calculates it exactly.

I think at the end of the day if the collar fits then you've made the right choice.  How tight/loose it fits is a matter of the owner's choice (in my experience for dogs and horses) so this is not an exacting process.  I typically measure a collar/bridle that fits to the owner's satisfaction and make mine the same size (plus padding allowance if needed).  The calculated padding allowances are small and I only recently did the calculation out of curiosity.  I haven't had a problem making dog collars and nosebands as flat straps then wrapping them in a circle.  The noseband above is made from 2 layers of 9 oz leather and I've made dog collars in a similar manner.  They close in a circle without a problem.  I sometimes bend the buckle turn with my fingers to match the curvature (3 layers thick and skived on the end).  I am using Hermann Oak regular veg tan or bridle leather.  I typically apply a light coat of neatsfoot oil followed by conditioner at the end of the project.  Perhaps you could show us pictures of a collar that isn't shaping up.

[Sarina]

On 3/21/2024 at 7:52 AM, TomE said:

I think at the end of the day if the collar fits then you've made the right choice.  How tight/loose it fits is a matter of the owner's choice (in my experience for dogs and horses) so this is not an exacting process.  I typically measure a collar/bridle that fits to the owner's satisfaction and make mine the same size (plus padding allowance if needed).  The calculated padding allowances are small and I only recently did the calculation out of curiosity.  I haven't had a problem making dog collars and nosebands as flat straps then wrapping them in a circle.  The noseband above is made from 2 layers of 9 oz leather and I've made dog collars in a similar manner.  They close in a circle without a problem.  I sometimes bend the buckle turn with my fingers to match the curvature (3 layers thick and skived on the end).  I am using Hermann Oak regular veg tan or bridle leather.  I typically apply a light coat of neatsfoot oil followed by conditioner at the end of the project.  Perhaps you could show us pictures of a collar that isn't shaping up.

I think that makes sense. For me I am making collars for people so they're a little bit larger and might be a little bit different. Here is an example of one I made, this one I made each layer smaller than the one on top of it so that I needed to form it partially rounded to fix them together and have the ends match up.

There are 3 layers, the first one is neoprene foam wrapped in sheepskin, which is stitched to the second layer of leather. The second layer is fixed to the third layer of leather using Chicago screws. The first two layers usually bend fine since they're stitched together making it more like a single piece but the second and third layer have a hard time going into a circle. For this piece I didn't give enough extra room in between rivets for the D rings either so you can see the bottom layer caves inwards.

Since for this one I did it more like Dwight explained, not flat to begin with, it ended up being mostly okay. For ones I make completely flat the leather tugs hard on the Chicago screws when it's formed into a circle, and it ends up a little bit misshapen. I don't have any pictures of that since I ended up trashing the leather and starting over.

 

On 3/20/2024 at 11:48 PM, Dwight said:

have access to power tools and lumber . . . so for me to make a circle that is 13 inches in diameter is a piece of cake . . . taking me all of 25 to 30 minutes . . . I would staple or otherwise fasten the inslde piece of leather to the wood model . . . form the rest of the pieces . . . and then using an awl . . . punch thru the leather . . . into the wood . . . for the stitching.  

Once the pieces are made  . . .  I then glue them together with Weldwood contact cement . . . and they are easily stitched using my Cowboy 4500 or in some cases . . .  sewing it by hand . . . with a stitching pony.

Having a wooden circle with the diameter you're going for sounds like it would be a lot easier. I actually considered something similar after reading your initial comment but decided it would be too much effort for each piece I'm making. I looked up to see if there was some expandable circle measurement tool, there were some but I'm not sure that they would work well. I think if I glue the pieces together in a circle (or half circle in my case) they should stay together like that long enough for me to poke holes with an awl. For punching holes I may need to clip the pieces together while they're in the circle shape, then mark with a pen through the hole in one piece where the hole in the other piece should go. 

Edited March 22, 2024 by Sarina