Leather Mold from wood?

[IvoryCreek]

Hi there again,

I'm trying to figure out what kind of wood (or other materials) is best to be shaped/turned into a leather mold that will allow me to create more structured leather bags and so on. I found this Youtube video quite informative "Making High Quality Leather Bag Moulds" but I don't really know which kind of wood will allow repeated use without the water and pressure changing the wood. 

 

Also, since I don't have a wood shop, are there places I can look at to have people make those molds for me? I'm in the US

 

Thanks!

[Northmount]

I've used pine, fir plywood, etc.  Moisture is not going to change the shape/size all that much.  Plywood might de-laminate over repeated usage.  You don't need a lot of pressure, so that shouldn't be a problem.  Leather does not normally need to be saturated with water. 

Wood with rough grain will emboss the leather surface, which you may or may not like.  Clamping against a smooth laminate will keep the leather surface smooth.  You can varnish or wax wood to reduce the amount of moisture it will absorb.

You can also use high or low density polyethylene, like kitchen cutting boards.  Or UHMW Polyethylene.  You will still need some hand or power tools to cut and shape the material.

Wood is easier to cut, carve and sand to the desired shape for molds.  Handy hand tools would include a coping saw, hand saw, rasp, mallet and chisel, sandpaper, ...

Tom

[Bigfoote]

I use spruce or pine. If the mold is going to be used a lot, varnish it or it will start staining your leather. Any carpenter or cabinet shop would be able to make molds for you.

[IvoryCreek]

Thanks guys, I'll look into your suggestions

[fredk]

I use MDF and varnish it.

A lot of varnish to waterproof it.

MDF is very easily cut with minor hand or power tools. Even a medium duty knife will shape it easily. MDF has no grain so it doesn't leave any grain imprint in the leather

[IvoryCreek]

thanks fredk! :D

[IvoryCreek]

sorry, some following questions: are there rules to which kind of varnish solutions I should use for different types of wood? and how many coats will suffice for a mold?

 

Thanks!

 

[fredk]

Basically, no rules on varnish.

I use a quick dry acrylic gloss varnish. A very thinned [with water] first coat, a second slightly thinned coat then around three or four top coats, lightly sanding in between each.

I'm not looking a decorative gloss finish just a good water barrier. MDF soaks up the thinned varnish like a thirsty camel. It takes plenty of coats of varnish to get the surface really sealed

[IvoryCreek]

got it thanks!

[IvoryCreek]

Help~I tried spar varnish on a plywood mold that I got, but even after 48hr sitting outside on my porch the surface is still sticky. i sanded the surface before I applied the varnish with natural bristle brush , what's going on?

also this varnish smells really bad...

[Northmount]

2 hours ago, IvoryCreek said:

Help~I tried spar varnish on a plywood mold that I got, but even after 48hr sitting outside on my porch the surface is still sticky. i sanded the surface before I applied the varnish with natural bristle brush , what's going on?

also this varnish smells really bad...

You got bad varnish.  Varnish may have a strong chemical solvent smell, but not rotten.   Needs to cure at 65 F or warmer.

Tom

 

[IvoryCreek]

can you recommend a varnish @northmount? Thank you!

[Northmount]

Just now, IvoryCreek said:

can you recommend a varnish @northmount? Thank you!

Spar varnish is normally a very good varnish.  Suitable for exteriors that are subject to some moisture and to sun.

Tom

[Thornton]

Modeling clay that you can bake in the oven would only require your hands to shape. Mistakes would be easy to fix before baking. No sealer required after baking. Win win win.

[fredk]

Well, thats certainly another take on it.

Polymer Clay, aka FIMO and Sculpey, are normaly available in 2 ounce blocks. It'd take a quare lot of them to make a shape for a bag tho. But each maker does a special bulk pack of around 1 to 2 pounds in certain colours at a much cheaper per ounce rate

[KittenThrasher]

On 09/02/2017 at 5:37 AM, fredk said:

I use MDF and varnish it.

A lot of varnish to waterproof it.

MDF is very easily cut with minor hand or power tools. Even a medium duty knife will shape it easily. MDF has no grain so it doesn't leave any grain imprint in the leather

I do much the  same, I use marine varnish and soak the MDF in it rather than paint it on, it takes at least a week to dry but I've had a few molds I made like that for years and used them a lot, they're still going strong.

[Boriqua]

I have made molds from a variety of woods. Poplar was better than the pine. Was smoother. If it was something I was going to do regular though .. I would find a local person with a CNC and have them make it from nylon. MDF is a water sponge, plywood has left unsightly grain marks on my leather, poplar and pine usually only come in certain widths. MDO would be great but its expensive and you still have to seal the edges. There is a Chinese company on ebay that does nylon molds but I think you could get them cheaper and faster from someone locally. Ask on you local craigslist for CNC guys. Display houses, wood shops and a bunch of other fabrication places have em and when I managed a display house we never minded throwing something on the CNC to make a few quick bucks from the machine that might otherwise be sitting there. If you are good with a vector program and you bring a file even better.

[IvoryCreek]

thanks!