Composite die's for gilt-metal or copper impressions 1

[hagatorn]

Hi,

I'm thinking of trying to form some thin metal sheet between two dies in a press.

Here is an example of a form cast in lead.

I'm thinking of casting the dies in aluminium but would also like to consider composites. I believe that many industrial Dies are made using one tool steal and one urethane for example

http://www.acrotechinc.com/metal-forming/.

I thought about experimenting with a one or more of the opposing dies being made from urethane or other composites as they can be cheaper and easier to handle than cast aluminium.

Would a cast Urethane be the most advisable composite? Should it be re-enforced with any glass or fibre product. I was initially attracted to it as I believe it is less brittle than many resins.

 

[MikeHalloran]

I think because of the severe deformation they are expected to endure, die pads are never reinforced with fiber; the fiber won't stretch enough. The urethane alone will take quite a beating.

How many millions of identical objects do you expect to make? That's pretty much the only reason to use tool steel, unless your workpiece contains a lot of nickel.

For one or two products made from copper, brass, or aluminum sheet, you could use single sided wooden forms and learn repousse`.

Remember that matched dies don't both need to be made of the same material. My friend Eddie Krymski saved a bunch of money and time by making half of a low volume body die set from concrete instead of steel. It was probably a new idea when he did it, now many decades ago.







Mike Halloran
Pembroke Pines, FL, USA

 

[hagatorn]

Hi Mike, Thanks

Yup, tool steel isn't feasible for this project. Think Urethane upper die is approved now. Will experiment with various lower die materials. Concrete may be worth a go it's certainly the easiest material to source and work with but I'm concerned about tearing the metal and the friction your likely to get from the conc. Also glass re-enforced epoxy might work? Could be easier to polish and wax. With the price and ease of the conc I would only need each die to work a couple of times and my runs will be short and hopefully high value. I've seen some pretty smooth conc. when full of polymers not grit for strength. Self levelling compounds for example. Might be easier to polish and so allow the material to run smoothly as it is shaped.

 

[hagatorn]

Also thanks for the repousse suggestion. My early efforts with a hammering approach were a bit frustrating and very slow.
Cheers
Craig

 

[mcgyvr]

hhmmmmm.. new idea.. get fancier buckets with patterns and take spent solder from wave solder machine to a "fancy pants art gallery" vs recycling at our solder reclaim vendor.