Stretching Tanned Snake Skin

[chgehrig]

since this is my first post, hello everyone. i am just getting into working with leather, and find this forum to be a very good source of knowledge. however, for my current problem, i haven't found anything on the forum as well as the googable rest of the web.

i have recently been given a box of old, huge boa skins. they are already tanned, black, and though they are quite old, they seem in pretty good shape: they are still supple, the scales are hard to tear off (even the very large ones). i intend to use them in a rectangular box clutch project i have recently started. because i want to glue them on a rounded (round on all four sides, that is) surface, i need to stretch them over it to avoid wrinkling. how do i do that without ripping the skins? it seems that glycerine and alcohol is used in the tanning process, and glycerine apparently makes the skins supple. would it be a good idea to rub glycerine onto the already tanned skins and then stretch them over the cast? or are there other ways?

[Tiara]

I'm a newbie myself but have mostly worked with snake skin for somewhat similar projects. More experieneced people may contradict what I do so don't do anything before you get more feedback.

However, I did do some checking on restoring leather with glycerin and found that the British museum uses glycerin and water to restore very old brittle leather. It is possible that the glycerin will hold so much moisture in that it can mold but this doesn't seem that common.

I found that some of the skins I have been working with are either much like paper to start with or become very stiff and dry after I dye them with spirit dyes. I found that mixing glycerin and water or glycerin, water and isopropyl alcohol which helps with drying time, and applying to both sides increases suppleness a great deal. Glycerin is a humectant, fancy word for something that draws in and holds water. So a bit of water in the mix speeds up the time that it would take for the glyerin to pull water out of the air. Right now I have a couple of snake skins hanging to dry after I applied glycerin and water but no alcohol. They have been hanging in an area with normal room temps and air flow, not near a heat vent for about 3 days. It may take about another 24 hours before the water evaporates enough to glue to a backing.

I'm cross checking final feel against another skin that I used the mix with alcohol. I think that does't leave it quite a supple.

Alcohol itself can be used as a "shoe stretch". Some shoe stretching products are made with alcohol, small percent of water and glycerin. Sprayed on shoes, worn until dry so that they conform to the foot better.

I've noticed when I glue snake skins, that the glue itself makes them temporarily softer and more pliant. I have a python skin that is much thicker and doesn't change as much with the glue. When I glue them to backing, if the backing is also quite thin, when the glue dries the backing will curl a bit. As those laminates are then used glued to a metal wrist cuff, the final product isn't wrinkled.

So far I've not had a problem with gluing the skins treated with glycerin not sticking even if applied to a smooth surface or lifting loose later. But none of those have been glued on more than 6 weeks. I have found that gluing to pliver--found a couple of sources on ebay, that the skins are easier to work with. Pliver or skiver are very thin skins used for doll making and other craft work. I've found white, black and at times a few other colors available but those are the only ones I've needed.

I have rubbed straight glycerin on the skins but found that mixed with water worked better. The 'straight' glycerin took days to pull moisture in unless we had a rainstorm.

I hope other more experienced members can post so we both can find out how well this works out over time.

[chgehrig]

thanks a bunch for your informative reply. i found that it was just my lack of technique that mad the skin crinkle and rip, as the skins are really still supple. i have remodeled the cast for the casing to have much rounder edges, making it ever so much easier for me to stretch and glue the skin over it (it's made from a recycled plastic polymer that is easy to heat up and form) - i don't quite know whether my skins are boa or python, but they are huge (the largest is 4 meters, or 13 feet long - the hide stems from what i imagine to be an unfortunate victim of poaching. the person who gave them to me couldn't say how old they are, but they seem very old) and quite thick, and don't react to the cobbler's glue all that much. i will do some glycerine experiments myself with left over scraps, it's such an interesting material to work with!

[Tiara]

I don't know how often boas are hunted for skins or how big they get on average. Anacondas and pythons are enormous. Right now pythons in the Everglades are a severe problem. A month long hunt in a recent article showed only 27 caught in the first 2 weeks with 800 permits issued. http://www.nytimes.com/2013/01/24/us/florida-mounts-a-hunt-for-creatures-that-maintain-a-very-low-profile.html?pagewanted=all

One female radio tagged and released was over 17 feet when caught again and had 87 eggs in her that were fertile. I started checking for sustainability of the snake species I wanted skins for. There are conflicting reports on how effective farming of captive bred snakes is, captive raised wild harvested eggs or hatchlings and how many skins come from wild caught snakes either legally or poached. There are confirmed reports of large pythons living in cities like Bangkok. The success of pythons in the Everglades and elsewhere and possible report of a breeding pair of King cobras there also makes me think that the hunting in their native habitat is unlikely to endanger them. Loss of habitat may be an issue but with the reports on just how hard it is to hunt these species indicates to me that breeding adults in jungle type habitat would be hard to eradicate.

I also find snake and caiman skin fascinating to work with. I prefer light colored skins to dye myself and the way scales may take up dye around the edges more deeply than the center if I don't overload gives some lovely effects. Add in some oils to give depth and then I've found some highlighting acrylic based paints that accentuate the textures even more and I'm enthralled.

Post some pictures of your project please?

[Fat Dog Leather]

Late in the game to jump in.....but here goes.

I have a large python skin in excellent shape that I am attempting to turn a 90 degree corner on a money clip project. Suggestions I have received to hold down the scales that flip up as the corner is made include the use of; varnish, white glue and most recently Mod Podge. I have tried the mod podge and it takes several coats to layer it under the scales as it turns and then with a final coat. Seems to hold for now, but being a newbie... I could use the advice.

Thanks.