PETG Glazing Sheet FAQs



Q:
What it PETG?

A:
Polyethyleneterephthalate Glycol Sheet (PETG), a crystal clear material supplied covered in an easy peel protective film to prevent scratching.

Q:
How do I cut PETG?

A:
The easiest way to cut this material is by scoring it with a sharp modelling knife or scalpel, bend it along the score, straight lines should break cleanly, curves can be slightly ragged & will need tidying up. In either case there will be a raised edge along the score line, the edges will clean up with a fine abrasive, file cards work well, or scrape it with the knife blade. When cutting curves it is much easier to make radial cuts on the 'waste' side & remove the material in sections. For cutting curves there there are special tools available but sheets can be scored using either engineers or draughtsman's dividers. A fair degree of pressure is needed, so it's advisable to use the type that has a screw adjustment to avoid unwanted movement. Those who have worked with polycarbonate sheet will find PETG to be similar (for modelling purposes).

Q:
What adhesives do I use?

A:
It has a useful reaction to different solvents. EMA Plastic Weld works well, giving good mechanical strength. Humbrol Liquid Poly has no noticeable effect, ideal for fitting glazing bars or fixing windows to styrene without the risk of surface damage from excess solvent. The effectiveness of other solvents will be assessed in due course.

Q:
Can I permanently bend PETG?

A:
Yes, it softens at 80C. To permanently bend it, tape to a curved surface then steam it over the kettle, or soak in hot water. Use any curved surface that can cope with heat & moisture, metal bar, tubing or ceramics i.e. the side of a coffee mug, whatever is about the right size, go for something slightly smaller than needed, the plastic will spring back a little when removed. Some trial & error is usually needed! Another method is the gentle use a heat gun, but be VERY CAREFUL, or you will end up with liquid plastic. When heating any plastic, do so IN A WELL VENTILATED AREA. Alternatively glue the sheet to ribs or formers (also cut from sheet).

Q:
Is PETG suitable for vacuum forming?

A:
Being a thermoplastic it is ideal for vacuum forming, at temperatures between 120C - 160C.