Double sided grinding flat plate

mnhms said:

Hi Guys, need your kind help on double side grinding. I never use grinding machine before. May I know is there a possibility to grind flat plate (100mm x 100mm) from 3mm to 0.8mm using double sided grinding or double disc grinding? I've used end mill but very difficult to control warpage during milling due to imbalance stress develop during milling. So, I am interested to use double sided grinding to encounter this problem.

I've attached image milling using end mill. The material is torlon.

Click to expand...

Milland said:

Have you talked with your material supplier about having them cut or source the material at the flatness and thickness you need? It might even be worth a USA vendor search if you can't get it in Asia.

Double disk grinding should be able to make the parts to thickness and flatness, but surface finish may be less than ideal, or the process may be too slow if finer grit wheels are used.

Perhaps a vacuum chuck and PCD insert tooling would allow traditional machining with less stress and heat, and easier flipping between cuts. I suspect that would give you better results than what you have now.

Click to expand...

mnhms said:

The item is sell at standard thickness which is 3mm, 4mm, 6.5mm, and 9.5mm. Yes I'm from Asia and since we are in high mix, low volume mode so getting a custom thickness would be difficult since order number is small. This attached plate indeed been milled using vacuum chuck only the tool used is carbide. We might need to evaluate PCD then to see if it is worth to try. Thanks for your opinion.

Click to expand...

thermite said:

My other residence, 28 years, is in Asia. Human brain is much the same, anywhere.

Chinese would make a pair of heated plates and "adjust" to wotever thickness was wanted. Each one different if that was wanted. Or maybe even each one different if it was NOT wanted... depends on how s****y the "Walmart" buyer is being, that visit.



Torlon is a tough, high-temp (very!) "thermoplastic" material, but it remains what it is:

thermoPLASTIC.

You can make heated / heatable platens in 100 mm by 100 mm ONCE for less effort than trying to mill it "right".. forever..

THEN you can sand the last small increment for great flatness, and rather more rapidly.

And recoup your costs for the platens by selling custom sizes to other R&D folks who have no solution.

There are no problems. Only opportunities.

Click to expand...

mnhms said:

It is good and might be workable idea and I will think about it. But isn't it by deforming a plastic using heat means that it can affect their mechanical properties since it will undergo re-crystallization process again during cooling? Or is it we have to retreat the material after process which actually would take minimum 10 days for Torlon.

Click to expand...

thermite said:

You do, indeed, need to research all of that. The other option, of course, is to "piggy back" off the already researched knowledge of a custom fabricator / distributor of these very goods.

Too many entities balk at a "premium cost" for that, go off to "reinvent the wheel, alone, and in the dark" (or so Bill Godbout once warned me. I made it work anyway!), end up spending far MORE money..

.. and worse? Wasting so much TIME that some other entity has already gotten the job done, is shipping product, and is banking the income. One of the worst sins in any competitive enterprise, any continent, BTW. Tends to be fatal.

The decision over which course to pursue is a management function. Not a technical one.

All I expected from my Directors of Engineering was their best assessment. "Rolling dice" on the basis of it thereafter was in my job description. Not in theirs.

FWIW-not-much? I'd already be using some other material and/or changing the design so as to "get to the end". No such thing as "irreplaceable". Never only ONE way that can work.

Up to you to help make winners out of your next-higher folk... rather than losers.

Click to expand...