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snapman
09-10-2007, 12:48 PM
We are having finish issues with our die cast parts- we originally wanted a smooth surface for plating and were then told by our mfg that smooth was not possible and that a light matte finish was better for plating regardless.

Long story short- getting the manufacturer to get us the parts (two parts, need the finish to match) with a matching surface texture has been a nightmare since they had the dies (molds?) made at different shops - and our customers do not like the matte finish- would prefer polished or brushed.

Is it possible to die cast zinc (zmak 3?) with a smooth finish? Not a mirrored finish, but a smooth surface suitable for plating straight out of the die or with minimal manual labor afterwards? Right now, to get a smooth finish, a lot of material needs to be removed due to the texturing on the surface.

Any help is greatly appreciated.

snapman
09-20-2007, 07:17 PM
Anyone?

Any ideas on where I can find out? Anyone know of anyone I can contact who does this sort of thing and would know the answer?

Thanks

One of Many
09-20-2007, 08:11 PM
Have you tried any web searches?

Just a cursory look see for "Die cast" + plating, resulted in several shops in the know.

Here is one full service provider (http://www.raylewisandson.com/capabilities.htm)

Of what I have seen in the process, the material is still very hot coming out of the die while the surface may be be near fluid. Some part geometry may dictate the part needs to be pushed out before it cools and shrinks so much it can't come out of the mold. This, as I understand it is what screws up the finish as it pulls away from the die surfaces. While that may be the case for zinc, you may not be able to just switch materials for many reasons.

Seems to me I have seen other methods that allow zinc to be cast in silicon molds that come out very smooth. Getting plating quality finishes can still be a lot of hand labor to prep it for copper flash and possibly more handwork prior to chrome.

By the looks of what I found, there are plenty of shops that can put you on the best path.

DC