cutting a rubber extrusion die with EDM-need advise on kind of equipment to buy

I would like to hear some advise from those of you who have done it. I need to be able to cut intricate profiles on metal plates of ~3/4" thickness. These plates are used as dies for shaping continuopus profiles in rubber extrusion.

How large are these plates?

These plates I need to cut are between 3" dia. to ~16" dia. Mild steel.

This may be a case where an alternative (possibly water jet) could provide the accuracy you need at far less cost than wire edm.

How intricate are the profiles you require and what kind of accuracy is needed?

Thanks Precisionmetal.
Right now we cut the dies by hand. We use a bandsaw to cut the profiles. This is the traditional method to do this. I Heard a competitor was using an EDM to cut the dies, but of course when I asked them if I could visit to see their set up, they said NO. It is not that the profiles are too intricate, but due to the swell of rubber after it leaves the die, which will vary with the cross section thickness, the die cutter "estimates" the amount of swell and will adjust the cut profile accordingly. We cut from small window seals to dock fenders. I also heard that after the drawing of the required profile is drawn using Autocad, the information can be trasferred to the EDM to cut the plates.

Juan,

From what you describe, it sounds to me like waterjet is the way to go as proposed by PrecisionMetal. Waterjet will kick these out pretty quickly.

TMD

Juan,

Nowadays, virtually any type of CAD data (Autocad or otherwise) can be converted in some way to be read by a CAM program. That CAM program will generate the required code to control a CNC milling machine, a waterjet cutting machine, a wire edm machine, or any other type of computer-controlled positioning/movement system.

I am not necessarily trying to convince you that wire edm will not do the job, it's just that is sounds like waterjet would be plenty accurate and would be much more cost effective.

A good quality waterjet machine can hold accuracy to about .010" in the thickness of material you're talking about. The surface finish would also be quite good, and if the operator doesn't "push" the machine too hard... the corner/edge will be quite sharp with no burrs.

PM

Juan,

I know what you are talking about with regards to the extrusion dies. You are transitioning from a round diameter to a profile. I doubt very much that a waterjet is going to give you the desired results. If it was me (it isn't) I would be looking into getting an Agie 100 or an Agie 120. Either of these machines will serve your purpose quite well. You can find re-built/reconditioned Agie 100 and 120 machines from 20k to 30k. Either of them, providing you don't crash them, should last you 20 years.

Whatever brand Wire EDM you buy, do yourself a huge favor and place it in an air conditioned room, by itself. You will thank yourself over and over again for doing so. Keep the air temp a constant 70 degrees and smile.

D_C

I am also in Canada and have been building extrusion dies for over 30 years. I built dies with hammer and chisel before the bandsaw. I have a Charmilles Wire EDM and hole popper. I can give help on design and I can manufacture what ever you want or need. Fast turn around. [email protected]