Flatness of G10 after milling

[TeoKL]

Is there any methods/tips to improve the flatness of machined G10?
The raw material's dimension is around 360mm*360mm*2.0mm, the target thickness for milling is 1.0mm. After that, it will part off to a circular disc with O.D. of 320mm.

Significant "bowl up" effect was observed (>0.30mm). Is there any way to improve the flatness, my target is (<=0.10mm).

Thanks.

 

[MintJulep]

Wouldn't it be a lot easier to just buy 1mm G10?

 

[3DDave]

Mill half off from each side. Or stress relieve.

 

[EdStainless]

Half off of each side, and you do know that the properties are not going to be the same.
How are you machining it?

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P.E. Metallurgy

 

[IRstuff]

https://www.artisansupplies.com.au/...r-material-300-x-300mm-sheets/?c=22783a5940ef

https://www.eplastics.com/sheets/micarta/g10-fr4/custitem17/0.030

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[Compositepro]

Composite materials inherently have internal stresses between the resin and fiberglass fabric. They are not isotropic like metals. Fabric styles can vary. Grinding into the face of the material will change the balance of these stresses, which will result in warping of thin sheets. If you want flat sheets you need to mold it to final thickness. Even then some warp is likely.

 

[3DDave]

Oh, G10 FIBERGLASS, which is a partial description. And I see it related to Phenolic and Epoxy resins. Sweet.

I do so dislike mind reading questions.

These guys supply it at 0.047 inch thick, 1.2mm or so.

https://www.curbellplastics.com/Sho...0-FR-4-Glass-Epoxy-Sheet#?Shape=CRBL.SkuSheet

 

[TeoKL]

Wow, thanks guys. There were a lot information provided. I am new to this industry(and this forum too). The reason my company don't buy the 1mm thick G10 is because there are other things we need to control(surface roughness, tolerance of thickness +-0.10mm).
Sorry for misleading, I did not notice that i forgot to mention G10 fiberglass.