www.recumbents.com - Ovens for acrylic & poly
www.recumbents.com
www.recumbents.com
Home | Profile | Register | Active Topics | Members | Search | FAQ
Username:
Password:
Save Password
 All Forums
 www.recumbents.com
 General Topics
 Ovens for acrylic & poly
 New Topic  Reply to Topic
 Printer Friendly
Previous Page
Author Previous Topic Topic Next Topic
Page: of 2

warren
human power expert

USA
6255 Posts

Posted - 12/07/2017 :  15:51:31  Show Profile  Visit warren's Homepage  Reply with Quote
According to my notes while blowing bubbles in Bill's basement, Lexan Polycarbonate can be blown at 350F.
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 12/07/2017 :  17:02:00  Show Profile  Visit carolina's Homepage  Reply with Quote
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.

velosRus.com
Go to Top of Page

harv
recumbent enthusiast

412 Posts

Posted - 12/09/2017 :  06:35:39  Show Profile  Reply with Quote
link to a vac forming guide for polycarbonate. http://tinyurl.com/yahtpnla
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 01/07/2018 :  09:34:05  Show Profile  Visit carolina's Homepage  Reply with Quote
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.
————————-

velosRus.com

Edited by - carolina on 01/08/2018 20:33:22
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 01/15/2018 :  14:00:04  Show Profile  Visit carolina's Homepage  Reply with Quote
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.

https://youtu.be/JAoxsDYFhdg

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F182420607998

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

velosRus.com

Edited by - carolina on 01/15/2018 14:32:53
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 01/27/2018 :  10:16:04  Show Profile  Visit carolina's Homepage  Reply with Quote
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.

UPDATE:
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.


————————-

velosRus.com

Edited by - carolina on 02/08/2018 20:28:47
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 03/14/2018 :  09:26:18  Show Profile  Visit carolina's Homepage  Reply with Quote
Saving up funds for my oven completion. Need another element and some ceramic fiber board from ebay.
———————-

velosRus.com

Edited by - carolina on 03/15/2018 18:11:23
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 03/15/2018 :  18:10:15  Show Profile  Visit carolina's Homepage  Reply with Quote
Trying this polycarbonate i bought today in raleigh. Lil’ thinner than 1/16” as u can see. Feels like great stuff.

4 x 8 foot sheet $75 out the door.

These 3 frame windows will not haf to be heated but will go in frame below nice l hope. Polycarbonate is very flexible.



5 windows will go in canopy below. I hope the side windows do good without heat. Fun to experiment.



velosRus.com
Go to Top of Page

harv
recumbent enthusiast

412 Posts

Posted - 03/17/2018 :  10:36:10  Show Profile  Reply with Quote
FWIW .032 polycarbonate can be cold bent in a sheet metal bending brake.
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 03/17/2018 :  12:49:26  Show Profile  Visit carolina's Homepage  Reply with Quote
Thanks harv! Want need, as u can see the pics. They just set in place in frame. I will finish my oven with more $$$$. And may not use it much but Wanta finish it anyway. Now it runs great @145 to cure parts but need the ceramic fiberboard and another element. Even if i leave frame out and install a full heated one-piece molded windshield, iam worried bout pedal clearance up front there with this bd5 canopy. Really goes down in front.



Your idea is great for trike or 2 wheeler, one who just wants a windscreen. Thats what lognotching (youtube channel) does on his nice trike tops.

Nice channel: ed miller, https://youtu.be/vAlKhBO_b2U
————————

velosRus.com

Edited by - carolina on 03/17/2018 12:52:42
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 04/25/2018 :  17:58:33  Show Profile  Visit carolina's Homepage  Reply with Quote
Harv: l did buy 0.30 petg for side windows and that worked out great. These windows are not heated or bent. 0.30 is really all i need to use in front windows also, (used 0.40) if l build another canopy top.

The 0.30 can be hard to find in alot of areas which makes shipping and purchasing high$$.


_______________

velosRus.com

Edited by - carolina on 04/25/2018 18:02:13
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 05/29/2018 :  19:45:08  Show Profile  Visit carolina's Homepage  Reply with Quote
How high will AirCrete go in temperature? Some inch thick panels would line an oven great if it would do 320 f degrees. Gotta find a local company that sprays AirCrete (youtube: type it in) and maybe get them to spray some in a wood mold.

velosRus.com
Go to Top of Page

DougC
Starting Member

USA
11 Posts

Posted - 05/30/2018 :  13:39:30  Show Profile  Reply with Quote
quote:
Originally posted by harv
...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.

Warning: I may not know what I am talking about. And I've never made any canopies.... -But I have heard about the entrapped-moisture issue. And I've seen it myself when bending plastics with a heat gun.... The solution I was told was to pre-heat the plastic at 150F for 2+ hours in an oven before you actually form it (either by heat gun or by oven).

It would seem that heating it to over 212F would be counterproductive. The reason the bubbles form is because water trapped inside the plastic boils. So to drive the water out, you don't want to heat it hotter than boiling...?

Edited by - DougC on 05/30/2018 13:40:21
Go to Top of Page

carolina
recumbent guru

USA
827 Posts

Posted - 05/30/2018 :  14:46:56  Show Profile  Visit carolina's Homepage  Reply with Quote
But i cook cell cast acrylic; its 320 for 10 mins. This is no blown, this is simply dropped into a female mold for this oven.

My petg is straight or almost in a window frame, i don’t use polycarbonate, i like petg. Also i use only 0.30 which sometimes haf to order.

velosRus.com
Go to Top of Page

harv
recumbent enthusiast

412 Posts

Posted - 05/31/2018 :  07:16:33  Show Profile  Reply with Quote
Doug, you're right and you're wrong. 250°F is hot enough. Lower temps making the time required impractical. I'm attaching a link to a technical article about forming PC and there are many to be found. http://tinyurl.com/y7mh3z4s
Go to Top of Page
Page: of 2 Previous Topic Topic Next Topic  
Previous Page
 New Topic  Reply to Topic
 Printer Friendly
Jump To:
www.recumbents.com © 2017 www.recumbents.com Go To Top Of Page
Snitz Forums 2000