HB - I posted most of this in answer to this same question over on CKD. You already got some good advice but I'll add my two cents worth here.
I prefer Fiebings Pro dyes, but the Lincoln brand is also very good. Something I didn't put on the CKD post is to de-glaze you leather first. I use denatured alcohol and if that doesn't quite get cut it I use acetone. You can get leather de-glazer from Fiebings or Tandy but the above two are cheaper and work just as well. Also you can thin the Pro dye with alcohol to get a lighter color.
1) Dampen your leather with water just before dying. This opens the pores and will help you get an even coat, but it is still difficult to get it really even.
2) Use an airbrush or paint sprayer.
3) The simplest and easiest way and the method I use is to dip dye. When making a sheath I first dye the inside (before sewing) by using a swab and then seal it with either Fiebings Leather Balm w/Atom Wax or Natural Watco Danish Oil (it's a wood product). Use 3 or 4 LIGHT coats of sealer instead of heavy ones. After everything is sewn together I gently plug the mouth of the sheath. For pouch type sheaths I use a wadded up plastic bag, for blade only sheaths I use a piece of wood whittled to fit. I keep five gallon buckets of dye on hand most of the time, but for a small batch I take a quart of dye and pour it into a plastic container that is big enough to put the whole sheath into at once (those cheap plastic "sweater" boxes work great-just don't store the dye in them as they aren't air tight and the dye will dissipate). If dye isn't deep enough to cover the sheath completely just turn it over and roll it around until you get nice even coat. Take it out of the dye and wipe any excess off with an old towel. With either type remove the plug and hang the sheath up to dry. On a pouch type sheath some of the dye will have probably leached down inside around the plastic bag plug. Just pull out the bag and wipe it off with a rag dampened with denatured alcohol while the dye is still wet.
When the sheath is COMPLETELY dry thoroughly wipe off the fine film of dye powder left on the surface. If you don't get this film off before applying your final finish it will leach through and rub off onto everything.
Bone/smooth your edges again and if you're going to mold the sheath around the knife dampen the leather and do it now before adding the finish. Depending on what type of finish you want I use one of the following water resistant finishes:
semi-gloss: Fiebings Leather Balm w/atom wax
low-gloss: Fiebings Tan Kote
oil type: Montana Pitch Blend (a mixture of mink oil, pine pitch, and beeswax-similar to the oil/wax bath but you just have to rub it in)
Remember always use several light coats of finish instead of heavy coats. With any of these suggested finishes if you get too much on, rub the leather down with a clean denatured alcohol rag and then reapply.
As always practice/experiment on scrap.
Hope this helps
Gary-
The trick to using USMC is to de-glaze and while still damp dye it immediately. It will penetrate very well then. It does leave a film of powder on your work more than others, but if you buff it off as I said above it won't rub. A little trick for getting a deep blue black dye is to dye with navy blue first, let dry and then dye black.
Mike Hull- is spot on about the oil finish and if you add a little bit of olive oil (about 10 to 1 ratio) you get an even richer color. Put it out in the sun and it will darken even more. The only difference between Mike's method and the traditional saddle makers oil finish method is that you heat the oil instead of the leather. I use a crockpot or for bigger pieces a roasting oven and bring the oil temp up to 180F (do I have to say don't use the one in the kitchen!). Dip the item in and the warmed oil and then like Mike said wipe it off and let it drip dry for a while. You can also wrap it up in an old towel to wick off the extra. An oil finish will soften the leather a bit so don't over-soak it. It's almost impossible to get the excess oil out.
I also use Siegel at times and I'm not bad mouthing them but be aware that they do up grade their leather sometimes. i.e. I have bought sides of 3/4oz that is actually 2/3 oz. I have also had hides come in with two different markings as to the number of square feet and then have the invoice say a third. I'm not the only one who has had this happen to them. I do know that master leather smith Sandy Morrisey (helmar) uses their 7/8 oz vitan shoulders for his sheaths.
After 40+years of buying leather I have settled on one supplier for all my veg-tan needs.
It's Wickett and Craig. Check them out at
http://www.wickett-craig.com or call Matt Bressler there at 1-800-826-6379 ext216 and ask for a sample pack/catalog. Their 8/10oz tooling/holster/carving in the utility grade goes for $4.46 a foot. You can also get backs(It's what I use-no belly leather) for $.85 a foot more. You have to call for the backs. You can get lighter weights by calling and having them split at no extra charge. This gives a very smooth, clean backside. Also they have pre-dyed black sides so I don't even bother dying with black anymore. They also have a beautiful chestnut color in their saddle skirting selection that is really nice (it comes in 8/10 oz also)
