Leather 101

[go_hercules]

Hi, all the projects I have done so far have been in vinyl (mostly motorcycle seats).  As Schultz would say, "I KNOW NOTHING" about leather.  Could someone summarize what I need to know before taking on a leather project.  For instance, what sizes hides or partial hides are sold in, rough costs, different thicknesses or weights used for automotive, different qualitities to be aware of, what to avoid when ordering, etc.   Thanks a lot.

[mike802]

The size of the hide depends on the size of the cow.  Usually they run about 50 square feet pr hide, 25 square for a half hide.  When working with leather it is good to know which direction the hide will stretch, usually it will stretch one way more than the other.  Also watch out for which way the hide wants to rip, it will rip very easily in one direction, but be difficult to rip in a different direction.  These things should be watched out for when working with each individual hide.  You can expect to pay anywhere between 4.25 to 12.00 dollars for a square foot.  Other than that it is very similar to working with vinyl. I am sure others will be along to give you their professional input on the subject.

[go_hercules]

Thanks for the info.  I wasn't aware that it would tear that easily in one direction.  Are there different "weights" or thicknesses to be aware of when ordering, or are all automotive leather hides a common thickness?

[Saddleman]

When working with leather it is good to know which direction the hide will stretch, usually it will stretch one way more than the other. 

Cows do not get longer when they breathe is a pretty good rule to understanding leather stretching.

Upholstery hides are typically 1.2mm to 1.6mm in thickness and 2.5 to 4 oz per sq ft.  Leather is like most things were you get what you pay for.  The best hides are full grain with top grain being next.  If it indicates split hide it will be low quality.

[go_hercules]

Thanks for that info.  It gives me a much better idea of what to look for now when ordering.  Thanks again.

[ThrowMeAPillow]

Belly leather is thinner and not as strong.  Also, you will see, looking from the underside, that the "underarms" have a strange grain.  They are not strong and should be avoided in stress areas.  

There is a knife called a Skive, Skiving knife or Skiver for trimming (thinning out, tapering) the edges of leather. (I imagine it is a combination of "skin" and "Knife" hence, 'skife').
http://www.youtube.com/watch?v=paMZhzwJmWc
AVAILABLE TO BUY AT: http://www.goodsjapan.jp/
here's one: ten bucks on eBay:
http://compare.ebay.com/c-s-osborne-no-925-skife-skiving-knife-leatherworking/like/160434225488

This prevents a thick line showing through from the back where the cut edge lies.  Check with places that sell leather carving kits.  Tandy Leathercraft used to be one.  The knife is a relatively cheap looking long folded blue sheet metal thing with a gentle curve at one end.  You insert a razor (single edge injection type) into that end.  There is a gap along the edge for the trimmed off leather to escape.  

Skife the edges before you roll or fold them back to sew. This will make for a much smoother finish. Lemme know if you cannot find one online.  There is a fancy one with a roller.  Mine did not work as well as the one I have described.  BUY PLENTY OF BLADES!

MARK leather with a wax 'chalk'.  (you can 'polish' it off if it shows) I have heard of people using a dry sliver of soap. (yuk)

There are "diamond pointed" needles for your sewing machine.  I usually do not use them since most of my lines are relatively short but THAT's what diamond point needles are for.  They pierce the hide more easily.  you MIGHT have trouble with the top thread when sewing if the hole closes behind the thread and won't let the take-up lever do it's thing properly.  A diamond pointed needle might help there too.  At first; just use a heavy needle (they're easier to find!)