Shoulder Strap Technique?

[MtlBiker]

I'm really a novice with leather (only started doing any sewing since Covid) and other than for a couple of wet moulded belt pouches with veg tan, all my (little) sewing experience has been with fabrics, canvas, Cordura and vinyl.  I just returned from a leather supplier where I bought a bunch of chrome tan leather for a project.  I'm a little stumped about how to make the shoulder straps with the leather.

Using vinyl fake leather, my straps started off being 2" wide.  Then I folded each edge into the middle, making the strap 2" wide.  Then folded in half again making the finished width 1" and stitched both edges.  I doubt if this would work well with the leather as it would be too thick.  So I'm wondering how I should make the straps.

Does it make sense to start with 2" wide and fold the ends in to the middle to make the final 1", with the join visible on the bottom?  Should I start with two 1" straps and glue them together and stitch the edges?  And then burnish the edges?  Is there a better way?

I haven't measured the leather I bought but the seller said it was about 3.5oz.  Four layers of that would probably be too thick.

Here is a photo of the bag I made using waxed canvas and vinyl... I'm planning on the same but using leather instead of vinyl.  You can see part of the shoulder strap.

Thanks for any suggestions.

[PastorBob]

51 minutes ago, MtlBiker said:

Should I start with two 1" straps and glue them together and stitch the edges?  And then burnish the edges?  Is there a better way?

That is exactly how I would do it.

[Hardrada]

1 hour ago, MtlBiker said:

Does it make sense to start with 2" wide and fold the ends in to the middle to make the final 1", with the join visible on the bottom?

That's how some manufactories do it. I've a bag that uses that method: fold at 1/4 of the distance from each edge, unfold, apply glue throughout the flesh side, fold again so that edges meet in the middle, end by stitching 1/8" (~3.5 mm) from the new edges.

Edited December 1, 2021 by Hardrada

[MtlBiker]

2 hours ago, PastorBob said:

That is exactly how I would do it.

Thanks.  Since I've never done this before, I guess the right thing to do would be to try both ways.  I'll make a couple of sample pieces.  I was asking, in case I was missing a better method.  I have LePage's heavy duty contact cement... any reason that shouldn't work well?

There are parts of that bag that are trim (not shoulder strap or handle parts)...  I'm wondering if a single thickness of leather with the edges burnished would look alright.  Or if the double layer with the join hidden underneath and the edges top stitched would look better.  That might just be personal taste, or...?  You can see the trim pieces in my above photo.

And about burnishing the edges... this does work with chrome tan leather, right?  I've only so far done this with veg tan that I've dyed.

[MtlBiker]

1 hour ago, Hardrada said:

That's how some manufactories do it. I've a bag that uses that method: fold at 1/4 of the distance from each edge, unfold, apply glue throughout the flesh side, fold again so that edges meet in the middle, end by stitching 1/8" (~3.5 mm) from the new edges.

I guess I'm going to have to try both methods.  I just wanted to make sure I wasn't overlooking a better method than what I'd thought of. 

I think what you are suggesting would work better (perhaps) for the trim pieces where they're attached to the bag so the underneath join/seam isn't visible.  But the edges, top stitched, would look very good.  For the shoulder strap and maybe the handle, it might be better with the two piece strap glued together and stitched and then the edges burnished.  SIGH  What I don't know about working with leather would fill a book! 

 

[Hardrada]

7 hours ago, MtlBiker said:

SIGH  What I don't know about working with leather would fill a book! 

There are plenty available!!!

 

Here, this is the bag in question:

 

Here's how they did the strap:

Not only did they cut a single strap and folded it and stitched it, but they actually put it together from two three shorter straps.  Waste not, I guess.

 

Contrary to my remembrances above, the glue didn't really go all the way to the centre or the edges—guess they only glued the area round the fold:

 

At some point a wayward cut happened, maybe an accident? Still, waste not, just stitch it in place and carry on:

 

Edited December 2, 2021 by Hardrada

[PastorBob]

14 hours ago, MtlBiker said:

Thanks.  Since I've never done this before, I guess the right thing to do would be to try both ways.  I'll make a couple of sample pieces.  I was asking, in case I was missing a better method.  I have LePage's heavy duty contact cement... any reason that shouldn't work well?

There are parts of that bag that are trim (not shoulder strap or handle parts)...  I'm wondering if a single thickness of leather with the edges burnished would look alright.  Or if the double layer with the join hidden underneath and the edges top stitched would look better.  That might just be personal taste, or...?  You can see the trim pieces in my above photo.

And about burnishing the edges... this does work with chrome tan leather, right?  I've only so far done this with veg tan that I've dyed.

I use Barge's contact cement, but yours should work fine.  I think you could use a single layer on the trim pieces without any fanfare.  As for burnishing chrome tan, I use tokonole (or a variant sold by Springfield Leather...or any leather shop). It works really well.  I just apply a little with my finger and rub it in, then run some canvas over that.  I don't even edge it.  Give it a try.

[MtlBiker]

I made a few test pieces for straps and other than for the roughness of the result, for a first attempt I'm encouraged.  I need to work more carefully on the edges but I think that both options mentioned (two straps glued together and one strap folded back under by 1/4 the width) would work.  I didn't try (yet) just a single thickness of the leather for decorative trim areas but if I do well on the edges that too should work well.

The only thing I don't like is that when the strap is doubled over like for a length adjusting buckle, or folded under to hide the strap end and then riveted the leather I have might be too thick.  I'm figuring it's just shy of being 5 oz leather (1.49-1.97mm) and doubled it measures 3.5mm and the folded over version is about 4.25mm.

Should I be using a thinner leather, like maybe 2-3 oz for the straps?  The finished product is simply a bag/purse as I showed at the beginning of the thread so supporting heavy loads isn't going to be an issue.

 

[Hardrada]

1 hour ago, MtlBiker said:

I made a few test pieces for straps and other than for the roughness of the result, for a first attempt I'm encouraged.  I need to work more carefully on the edges but I think that both options mentioned (two straps glued together and one strap folded back under by 1/4 the width) would work.  I didn't try (yet) just a single thickness of the leather for decorative trim areas but if I do well on the edges that too should work well.

The only thing I don't like is that when the strap is doubled over like for a length adjusting buckle, or folded under to hide the strap end and then riveted the leather I have might be too thick.  I'm figuring it's just shy of being 5 oz leather (1.49-1.97mm) and doubled it measures 3.5mm and the folded over version is about 4.25mm.

Should I be using a thinner leather, like maybe 2-3 oz for the straps?  The finished product is simply a bag/purse as I showed at the beginning of the thread so supporting heavy loads isn't going to be an issue.

 

The strap there in the middle is the one that looks best.

It also saves on edge paint, and on the hassle of said paint peeling off over time and with use.

RE: thickness: a doubled-up strap is also twice as strong, so, another bonus. You need to choose your leather thicknesses based on the weight of the bag. A bag like mine, the leather thickness is 1.07 mm, roughly 2.5 oz—doubled up is 2.38 mm. A heavier bag would require thicker leather. Choose your leather and then your hardware accordingly.

With thicker leather, it'd be very expeditious to carve a channel round the fold line on the flesh side with a stitching groover or even a V-gouge (the former would be best if you're using soft- to medium-temper chrome tan) to reduce bulk and make it easier to fold.

[RockyAussie]

Over the years I have used a lot of different ways to make the straps for purses and hand bags and a lot really depends on the looks, price point and machinery at your disposal. In the past I mostly made straps that were just 2 pieces combined and edge trimmed followed by sanding, edge painting, ironing in and further edge painting and polishing and generally doing a lot of work to achieve a nice result. One thing to point out here is that a single folded strap can be weak in the middle where a buckle is used both where the tongue goes through its hole and where the buckle crew punch hole goes. I prefer normally to double up on my folded straps for that reason. Having a band knife splitter I have the advantage of being able to make the thickness I want in MOST cases quite quickly and therefore I can easily make a folded strap to whatever thickness I want. That said I also employ the use of various folding guides I make and these days a Cowboy strap cutting and folding machine. This link shows a video I made of the said machine and guides. https://www.youtube.com/watch?v=LLIGfR1ehFI&t=397s

Just recently I was asked to make a range of products out of vegan leathers. Basically it is just a vinyl type of substance and should not be given the use of the word leather any more that almond juice can be called almond milk.. Although I can still skive the edges fairly well on a bell skiver it does not split so well as real leather.  I decided to use a couple of different techniques that you may find useful. The vinyl substance in use here is about 1mm. In this camera and round type bags I have used 3/4" folded strips combined together that if measured in the middle would be about 4mm (10oz).

Just getting my cows approval

 

The camera style bag

 

Now in order to get a thinner look I used in this clutch purse a 13mm strap covered with a 10mm strap on top (1/2"+ 3/8").

This give the impression of a thin strap whilst still being quite thick.

Hope that helps some.

[jrdunn]

That red cow looks as skeptical about it as I feel.  "Vegan Leather", we used to call it "Naugahyde".  I takes lots of Naugas to make a purse!