I do this a little differently.3D-Print wrote:Awesome thread!
I wanted to make sure I'm pulling this all together correctly. In summary, adding PEI is as follows... Correct?
PEI from amazon is: PEI (Polyetherimide) Sheet, Opaque Natural, Standard Tolerance, ASTM D5205 PEI0113, 0.03" Thickness, 12" Width, 12" Length
1) Triple-washed the glass, after scraping it down with a razor blade, a cleaner, then Windex, then isopropyl alcohol
2) Place the 3M tape
a. TapeCase 468MP
b. TapeCase 468MP 12in X 12in
3) Isopropyl EtoH clean the PEI, let it dry, then laid it down with a minimum of curling of the plastic.
4) Weight it down
Is that correct?
Thanks,
Dan
After doing the cleanliness next to Godliness thing, I apply the tape to the PEI first.
I pull the first inch of the cover sheet loose from the first side of the tape and carefully fold it back. This leaves an inch of sticky exposed across the full width of the tape (1"x12"). I position this carefully on the PEI sheet and stick it down. I then lift the free end of the tape sheet, grab the folded over cover sheet and start peeling it off while sticking the tape down to the PEI. This allows you to work the sticky edge down progressively and not get big bubbles or wrinkles. If the tape ever touches itself just get another piece because things will not improve with effort. After making it all the way across, I have a sheet of PEI with the tape on one side. Decided what side you want up before you start this drill, VERY IMPORTANT.
I repeat the operation to attach the PEI/Tape assemble to the glass. Again folding back about an inch of the second side cover sheet and I carefully align the PEI to the glass without letting the sticky touch. When it is in position push the sticky edge down and squeegee the tape down for the full inch width. Now the PEI can be flexed up off of the glass and the cover sheet again pulled from between the PEI and the glass by tugging on the loose end of the folded over cover sheet. Again work the PEI down onto the glass as the cover sheet is peeled to minimize bubbles. After making it all the way across you should have a tightly stuck PEI sheet with no large bubbles (lots of tiny ones) and NO TAPE WRINKLES.
I then lay the PEI/tape/glass sandwich PEI side down on a towel and using a sharp machinist scribe, score around the PEI using the glass edge as a guide. I really bear down on this and score about half way through (takes several passes), then break the corners off by flexing the PEI away from the glass side. Any sharp corners, edges or rough spots are cleaned up using a file. The plate is now ready to go, no cure time, weighting down time - just clip it, heat it, print it.
I have done four glass plates so far and used five tape sheets. It is really not as bad as it sounds and takes less time to do than it took me to type this diatribe.
Good Luck! The results are worth the effort.