Material Selection

[Morzfeldengineering]

Greetings.

I am designing a plastic injection molded assembly for a client. I am trying to find the best material for the plastic.

The assembly consists of a back and a front. The back is about 52" x 25" The front is the same size yet has large holes in it, resembling a grid. Both parts are about .500 thick, and I will have to core them out for proper wall thickness. The parts have to be screwed together and then hung on a wall.

There is no load or wear basically. Looking for the cheapest and proper type of resign.

Thank anyone immensely for any advice or direction.

John

 

[patprimmer]

Is it highly visible so finish matters? If so what surface finish is desired?

Is dimensional stability or warpage an issue?

Regards
Pat
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[Morzfeldengineering]

I guess the part is going to be coated to resemble wood. Something about a dip tank. However this might not be the best way to achieve a wood grain finish. This is a new client and I haven't discussed that part with him yet.

So yes it is highly visible and requires a good finish that resembles wood. (The frame) Dimensional stability is not that important as this is a trim or frame application. As the two parts are screwed together I don't think warp age will be much of an issue however it does need to be as straight as possible.

I was looking at abs for this and PP. I am actually a 20 year mold maker and just getting into the design part of the trade. My lack of experience with material engineering is frustrating, they all have good and bad parts. So I was thinking abs from what I read. But not sure.

Thank you for your reply patprimmer.

Respectfully,

John M

 

[patprimmer]

I'm with ABS so far.

PP might still wart beyond an ability to pull it straight even with screws. PP with an appropriate filler package might be OK as the dull finish will not matter.

ABS sticks a lot better to coatings, although some fillers also help PP with this.

Regards
Pat
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[TomDOT]

If it's that simple, why don't you just buy PVC foam board? You can get it already wood-grain finished.