Having problems with Vacuum forming for a visor

[APMuffin]

I am attempting to vacuum form an ODST visor using a DIY vacuum forming box following the tutorial from N8TEBB (awesome tutorial btw if you see this). I am having a problem where my PETG sheet turns white and opaque. I'm 99% sure I'm using PETG, as I purchased it from this link, but the actual package didn't include a label so I can't guarantee it. Any advice on how to remedy this issue would be appreciated.

 

[APMuffin]

I am attempting to vacuum form an ODST visor using a DIY vacuum forming box following the tutorial from N8TEBB (awesome tutorial btw if you see this). I am having a problem where my PETG sheet turns white and opaque. I'm 99% sure I'm using PETG, as I purchased it from this link, but the actual package didn't include a label so I can't guarantee it. Any advice on how to remedy this issue would be appreciated. View attachment 349695

Additional info, I had the bottom protective layer on still, but the opaque white color was on the plastic itself and remained after removing the protective layer.

 

[Billbill36]

I had this happen when I started vacuum forming, after digging into the description for the one I bought from Amazon I think it wasn’t 100% PETG, it had some impurities in there.

I ended up buying some from McMaster-Carr and ended up with much better pulls.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

It also might be a temperature issue? I think I saw people mention that before finding out mine wasn’t pure PETG

 

[PlanetAlexander]

Additional info, I had the bottom protective layer on still, but the opaque white color was on the plastic itself and remained after removing the protective layer.

Have you tried vacuumforming/heating it up without the protective layer on?

Like Billbill said, it may be a case of the mixture being different - this could be PETG with some other additive to give it another materialistic property, although it could be what is tainting the result.

Alas I haven't done any vacuumforming yet, so I couldn't provide a good resource to purchase from.

 

[N8TEBB]

What temperature are you heating to and how long does it take the plastic to start to melt? I’ve had issues where plastic is heated too quickly and caused bubbles. I wonder if this is an extreme case of that. Perhaps lowering the temperature might make a difference.

Other than than, it could be the plastic itself. They could have sent you the wrong item, mislabeled it, or are trying to scam people. Either way, if the issue persists, it may be worth buying from another seller.

Also, I’m glad you found the tutorial helpful!

 

[marinesniper]

The Last Visor i did the plastic did some thing kind of like that i had my heat to high and plastic to close it turned white like your but i dropped my heat a little and distance from the heat about an inch and i have had not problems ( knocking on wood).

 

[APMuffin]

What temperature are you heating to and how long does it take the plastic to start to melt? I’ve had issues where plastic is heated too quickly and caused bubbles. I wonder if this is an extreme case of that. Perhaps lowering the temperature might make a difference.

Other than than, it could be the plastic itself. They could have sent you the wrong item, mislabeled it, or are trying to scam people. Either way, if the issue persists, it may be worth buying from another seller.

Also, I’m glad you found the tutorial helpful!

I tried four different times, each at a different temperature. I think it is a temperature issue, as they all went white, but the lower the temperature, the longer it took. At 300f (~150c), it turned white after about 1 minute in the oven. At 275f (~135c), it turned white after about a minute as well. At 225 (~107c) it didn't turn white, but did begin fogging up, and I removed it before it could turn opaque and white. Finally, at 215f (~100c), it didn't go white, but it also didn't get hot enough for me to use on the vacuum former.

 

[N8TEBB]

I tried four different times, each at a different temperature. I think it is a temperature issue, as they all went white, but the lower the temperature, the longer it took. At 300f (~150c), it turned white after about 1 minute in the oven. At 275f (~135c), it turned white after about a minute as well. At 225 (~107c) it didn't turn white, but did begin fogging up, and I removed it before it could turn opaque and white. Finally, at 215f (~100c), it didn't go white, but it also didn't get hot enough for me to use on the vacuum former.

The highest temperature you used is what I usually do. So I don’t think temperature is the problem. I have a feeling the PETG you have is not pure PETG. You may have to pick some up from McMaster

 

[he4thbar]

I used his tutorial too!
My post
Here is the PETG I used and you can see in my post it turned out fine: Amazon Link
I had the same problem where it was white but once I took off the BACK and FRONT protective layers it looked fine, just spooked me since it was hard to find the edge on the back side.
Sorry to hear that is happening dude, best of luck to you