Home | Profile | Register | Active Topics | Members | Search | FAQ
 All Forums
 General Topics
 Ovens for acrylic & poly

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Format Mode:
Format: BoldItalicizedUnderlineStrikethrough Align LeftCenteredAlign Right Horizontal Rule Insert HyperlinkInsert EmailInsert Image Insert CodeInsert QuoteInsert List
Videos: Google videoYoutubeFlash movie Quicktime movieWindows Media videoReal Video

* Forum Code is ON
Smile [:)] Big Smile [:D] Cool [8D] Blush [:I]
Tongue [:P] Evil [):] Wink [;)] Clown [:o)]
Black Eye [B)] Eight Ball [8] Frown [:(] Shy [8)]
Shocked [:0] Angry [:(!] Dead [xx(] Sleepy [|)]
Kisses [:X] Approve [^] Disapprove [V] Question [?]


T O P I C    R E V I E W
carolina Posted - 09/21/2017 : 16:47:19
My oven is like this: 4x4 , 32" tall inside. Can do many of my molds for curing better and make some windows.


25   L A T E S T    R E P L I E S    (Newest First)
carolina Posted - 01/27/2018 : 10:16:04
Useing this large oven , tweeking my techniques. I lay acrylic on top of heat resistant sheet rock then 100% cotton. Heat to 320 and lay into female mold. I trim acrylic to shape of window and extra inch. Then the acrylic is totally laying down in the female mold with no krinkel around perimeter. Try to find some polycarbonate local tomorrow. Test it too.

This powder coating oven want do the trick, need to finish my home style oven one day (1 more element & 1 ceramic board). Sheet rock is ok for small oven but tile stone is best, like pizza stone(maybe Larry will find me one large stone). Oh if my kitchen oven was larger, it makes good smaller windows.


carolina Posted - 01/15/2018 : 14:00:04
Update and shopping for this ceramic board 1” thick liner, its high $$ on ebay. But l love it! Line my oven with it if found discounted at mcmaster-carr or Alibaba express.



Still a fan of the foam to build my oven from Home Depot with liner in it of the ceramic board.

carolina Posted - 01/07/2018 : 09:34:05
My first oven turned out great for curing all components molds at 145 degrees.

My friend owns powder coating bizz here and invited me to use his oven at 320 degrees.

I made a great miniature frt canopy windshield. [PHOTOBUCKET DOWN]. So i have some confidence.

I can use male or female mold, i have both. I choose to drape down into female mold with plastic on acrylic. And i have thin layer of felt on female mold. Windshield is 33” x 33” and pointed taper at front.

Start another oven with fire shield sheet rock, like in youtube above.

harv Posted - 12/09/2017 : 06:35:39
link to a vac forming guide for polycarbonate. http://tinyurl.com/yahtpnla
carolina Posted - 12/07/2017 : 17:02:00
But iam not use air, i use drape molding. Actually 320 could be lil high, probably even 300 f would work. This is very difficult. But l have plane B to start next week. A 3 window straight window frame plug of wood and bondo/duratec. Airplane plastics of ohio worked on this drape 2 piece mold method for over 10 years. Proprietorial & jeff want give any info out. And my buddy todd crashed and died. He would of helped me.

warren Posted - 12/07/2017 : 15:51:31
According to my notes while blowing bubbles in Bill's basement, Lexan Polycarbonate can be blown at 350F.
harv Posted - 12/07/2017 : 14:27:54
You have to dry polycarbonate ie 375f for 24 hours in an air circulating over. It's hygroscopic and will release entrained moisture as steam bubbles in the part. IIRC PC has a forming temp 450-500deg and would probably melt any poly cling film.

I think aircraft canopy fabricators would use greased felt covered molds for forming acrylic. The grease (crisco?) is softer than the hot acrylic and traps debris before it can leave a mark in the hot plastic.
carolina Posted - 12/07/2017 : 13:48:52
Harv, your version is best, just tried another. I might b able to do it correctly with your idea because the real mold for frt windshield is not compound at all compaired to this lil 10” sample mold i made. And its possible the polycarbonate will do a better job along with your idea of leaving the film on. Thanks. Every tip helps. This molding is very secretive. Will get some polycarbonate soon.

carolina Posted - 12/07/2017 : 11:03:19
Harv, gonna try leaving film on next one like you said. Tried 3 will felt and cotton based mold. Cotton best. Will post later today.

carolina Posted - 12/06/2017 : 16:05:45
Much better without felt,, but not good enough: hunt more info. My buddy who could have helped me was killed in his plane months ago.

This is the way l cut all plastics now:


Another molding of acrylic:

carolina Posted - 12/06/2017 : 12:32:09
Learning curve mini mold l made. Both pieces covered in felt.

1) 320 for 10 mins. 1/16th inch thick.
2) was simple.
3) cools in minutes.
4) layed acrylic on pizza stone, parchment paper, then 100% cotton piece (t-shirt material) in oven
5) textbook except for the felt impression left on acrylic.

My next hurdle is the felt left imprint on the lil mini piece. What to do next?? Maybe cotton??, or just the clean plain molds.

Took felt off of the lil’ molds. Start over with some new ideas.

Speedbiker Posted - 12/04/2017 : 19:51:25
Excellent video Mike.
carolina Posted - 12/04/2017 : 15:47:56
Yea, will get some poly next run. Never any vaccum forming here. I will try video above or use solution B as wrote above. Oven was built to cure part too. I am making part B or starting on that plug next week. I can use all 3 situations with the oven.

Ill check for UV harv, thanks. Piedmont plastics is a average supplier.

harv Posted - 12/04/2017 : 12:36:35
UV resistant PETG sheet is available. A tip: to help prevent scratches when handling AND vac forming petg, leave the blue cling film on and remove it after the vacform/trim operation.
warren Posted - 12/04/2017 : 11:01:51
PETG is the best option I found. It is inexpensive, melts at low temperature, forms well, and it optically clear. It is reasonably fracture resistant and does not shatter. Like most plastics, it will discolor or gt brittle if left in the sun. I have personal experience with blown PETG bubbles that are close to 20 years old and are still being used.
carolina Posted - 12/03/2017 : 15:25:08
1)Video again (below) has great technique but i use female mold instead of male mold.
2) my small test scrap mold for learning curve.
3) ya have to learn how first. Gotta start somewhere.
4) Speedbiker if l can do this with poly and be able to see thru it. Yay!


carolina Posted - 11/30/2017 : 16:05:36

Well, SB will get poly next trip to piedmont plastics but working on my cut techniques and heat transfers.

Making homemade ceramic washers for oven from free floor tiles and drill bit from lowes. [update] buy the lennox diamond ceramic drill bits only/$14.50.


Speedbiker Posted - 11/30/2017 : 10:43:40
Before I knew better I had Fox/Aircraft Plastics blow me a canopy. They used precision fast acrylic and a template from a F-1 race plane. While it would crack at every chance, and would be dangerous in a crash, but man was that thing BEAUTIFUL! Crystal clear and very low distortion.
carolina Posted - 11/30/2017 : 10:16:12
Yes thanks, but i will be experimenting for a while. CCA is easy to hold heat longer. Poly cooling is really quick. These are pressed in two part mold/male and female.

warren Posted - 11/30/2017 : 08:12:44
Note that acrylic shatters like glass, so it's not recommend for use in HPV applications.
carolina Posted - 11/29/2017 : 16:32:44
Trying acrylic “ cell casted “ first. Maybe later polycarbonate. Drove hour to get 4x6 foot sheet/$84 out the door. Two pieces 36x36” cut for me and the left-overs to practice with. I will show my practice pieces in a few days.

Working on ceiling up in oven, i can set in it. Two dropped aluminum ceiling’s in it then the heat element hanging below that on ceramic washers. 320 f degrees for 10 mins. Acrylic lays on piece of 100% cotton that covers the whole floor.


carolina Posted - 10/07/2017 : 12:04:11
Out side finished & door w/2 handles. Few weeks inside now.


Door is push in 3&1/2" thick.

carolina Posted - 09/27/2017 : 17:40:15
Caulking for a kiln came in, ebay 18$. Will shoot on seams inside first then more aluminum foil. 8 year record rip-off someone sold on ebay.





Garrie L Hill Posted - 09/27/2017 : 05:13:31
MIL spec is so passι! AS 9000 or NADCAP.

Garrie "carbon based lifeform" Hill
HPRA Co-Dictator of the East
for pics of some of my time and money sucking projects
and videos

Grant-53 Posted - 09/26/2017 : 21:52:16
Does it really need to be MIL STD? ;)

www.recumbents.com © 2017 www.recumbents.com Go To Top Of Page
Snitz Forums 2000