Hydraulic Die Forming Discussion Group

Phil Poirier
poirier@newmex.com

On Tue Aug 19 '08, hleshnick wrote
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>Should my copper sheet be the dimensions of the die (5x5) or the >dimensions of the box (6x6)?

The die should be the dimensions of the box, you must keep negative space to a minimum inside the container. You can achieve this by making your dies 6 X 6" square to fit the box. Also, you can make these acrylic dies much easier by cutting several 1/4" thick pieces rather than by cutting one thick piece of acrylic.


>Should my urethane pad(s) be the size of the box (6x6) or the size >of the die (5x5)? Can I use one 1 inch pad rather than two 1/2 inch >pads?

Again, you can keep the negative space to a minimum and maximize the die forming by using 6 X 6 urethane. When using urethane it is better to use two pieces of 60d X 1/2" than one 1". Use some lubricant between the two urethanes to get more forming at any given pressure.
You'll also want to use a 6 X 6 X 1" thick plate of steel or aluminum as a pusher.



>When I start stacking intensifiers, what is the durometer of the >intensifiers? Should all the intensifiers be the size of the die >hole, or should they decrease in size toward the bottom of the hole? >Do I continue using the initial urethane pad between the >intensifiers and the platen or do I press the intensifiers directly >with the platen.

Intensifiers are used as "extra hammer beats", use them where needed to get the result you want. They are typically between 80 and 90d.

>Should all pressings be at 4000 psi or should they increase as the >intensifier stack increases?

This will depend upon your desired results, write down your settings for future reference.

I would highly recommend that you take a workshop, there are thousands of details and tricks, too many to write in an email or forum, that will get you up and running much faster than learning by trial and error.

Phil