Suggestions needed on improving ABS sheet temps top to bottom

[jdougn]

I'm forming 3/16" & 1/4" black ABS for jeep fender flares but more consistency is needed. The sheets will not consistently pull into the details. It's a 2x4 TJ style with the oven on top. Forty gallon tank pulling 26-27 inHg. Typically holds around 18-20 inHg at the planten after droping the ABS.

I think the top of the sheet (towards the heat) is basically getting too hot while the bottom of the sheet doesn't heat up enough. Using a non-contact laser thermometer, the top of the sheet will measure around 380-390 while the bottom usually only gets to around 270-280 even after over-cooking.

- Cycling the heat on & off didn't seem to change much but I'm not sure about correct cycle times.
- Increasing the time causes the top of the sheet to orange peel.
- Added another 20 gallon tank but no change.
- Incresed vacuum hole size at primary details and did better but still not consistent.

So, what am I missing? Or what are suggestions to get a more even sheet temperature? Yes, I'm aware that 1/4" with single sided heat is maxed out. But with the knowledge on this forum there is a solution to the problem. I can always build a second oven to slide underneath the ABS but that is a last resort.

Thanks, Doug

[spektr]

Hey doug, call me at the shop, lets talk it thru..
leave me a number if you get my voicemail, my mother in law
is in the hospital and its a bit frantic right now....

Scott.

www.spektrproducts.com