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captmike Novice
Joined: 01 May 2012 Posts: 27 Location: Elberton, Georgia
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Posted: Sun May 06, 2012 12:09 pm Post subject: Toaster Oven for parts |
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I did a quick search here and did not find anything on using toaster oven parts to build a heater for the vacuum forming rig. Has anyone dissembled a toaster oven and reassembled the elements to use to heat the plastic? I am not making a big machine, it will be only 12 x 12. I am trying to make molds for 4" and 6" tiles.
Thanks, Mike |
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IMMark Expert
Joined: 18 Nov 2010 Posts: 189 Location: Columbus, Ohio
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Posted: Sun May 06, 2012 1:10 pm Post subject: |
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I haven't ripped one apart before, but you should be good.
There will be nichrome wire in there, some "temp" control.
You should be able to get something small, but interesting out of it.
Mark |
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Fredo Master
Joined: 21 Mar 2007 Posts: 251 Location: Kingdom of Nye Area 51
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Posted: Sun May 06, 2012 1:16 pm Post subject: |
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I think you'll find some thing like that in old posts of drcrash. Check his profile and see if his old site is still up. Mostly he was using thinner plastic. Thats not a bad place to start, then move up to something bigger, later on if you like it. I started with a 2'x2' then built a 12"x12". I use the small one more than the other. They are both the flip flop design, though the smaller now incorporates a frame that can be turned 180* as the plastic is heated.... I use .125 abs and usually only have a 10* degree temp difference front to back. Heating the plastic evenly and a good platen seal are the 2 most important things to getting a good pull... good luck and ask questions........... Fredo _________________ If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001 |
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captmike Novice
Joined: 01 May 2012 Posts: 27 Location: Elberton, Georgia
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Posted: Sun May 06, 2012 3:06 pm Post subject: |
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The oven I will be disassembling has two solid rods, two on the top and two on the bottom, each about 1/4" in diameter, inserted into a ceramic material. The plastic I will be heating will vary between .060 and thinner. I have .060 styrene to start with and it looks thicker than the molds I bought. I have my platen parts cut out and the holes are 1" apart and 1/8th " in diameter. I am using Corian material because I have lots of it. I think it will work well. |
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IMMark Expert
Joined: 18 Nov 2010 Posts: 189 Location: Columbus, Ohio
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Posted: Sun May 06, 2012 3:48 pm Post subject: |
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Those are called Calrods, they have the nichrome wire in the center of them.
Lots of different designs and you can experiment along the way.
My platens have the holes spaced at 1/2" apart, but really trail and error and see what works. Just make sure you get a good seal, that will help.
Mark |
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captmike Novice
Joined: 01 May 2012 Posts: 27 Location: Elberton, Georgia
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Posted: Sun May 06, 2012 7:27 pm Post subject: |
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I have dissembled the toaster oven and it will make a heater approximately 12 x 10 x 8 inches high. Will the two calrods on the bottom be enough or should I add a third on in the middle between the existing two? I could add the forth one, but that might be a bit much....I am new to these things. I also laid out extra points on the platen so I can place a hole every 1/2 inch if that would be better. I can drill the extra holes in about 30 minutes or less with the drill press.
Thanks, Mike |
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IMMark Expert
Joined: 18 Nov 2010 Posts: 189 Location: Columbus, Ohio
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Posted: Mon May 07, 2012 6:53 am Post subject: |
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It is a bit hard to have a specific answer, too many unknowns (watts, amp draw, etc.)
But given the plastics you stated, I would think you will have plenty of heat with 2. You can "adjust" the distance the heat source is from the plastic, how long you leave it on, etc. As for the platen holes, you may be fine with 1" spacing, try it and see. You haven't mentioned you vac system at all?
Or the size of the holes, FYI on mine they are 1/16"..I also have a fairly strong 2 stage vac system...and is a much larger machine.
Really, I would say experiment a little. Get a holding frame for your plastic, try it at different heights from the heat source, until you get what you want. Then build a more permanent machine.
Mark |
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captmike Novice
Joined: 01 May 2012 Posts: 27 Location: Elberton, Georgia
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Posted: Mon May 07, 2012 8:35 am Post subject: |
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The hole size in the platen is 1/8". The vacuum system I plan to use will be a portable air tank, small Harbor Freight vacuum pump and if needed, a shop vac. I'm going to keep this build as simple as I can until I learn more about what I really need. With one or two exceptions (vacuum pump) I have everything I need around the shop. I am stumbling a bit on how to build a good sheet plastic holder. I want one of the hinged types so I can go from the heater to the platen in one movement. I'll take some photos of what I have so far and post the ASAP>
Thanks, Mike |
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IMMark Expert
Joined: 18 Nov 2010 Posts: 189 Location: Columbus, Ohio
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Posted: Mon May 07, 2012 8:52 am Post subject: |
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You off to a good start. I think the 1/8" is a bit over sized, but I wouldn't worry too much about it. These kind of builds usually evolve.
There are a lot of good pictures here on the site to give you ideas.
And Fredo (who posted earlier) has a very nice little oven with a holding frame that flips and spins!
Post the pictures when you can.
Mark |
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captmike Novice
Joined: 01 May 2012 Posts: 27 Location: Elberton, Georgia
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Posted: Mon May 07, 2012 8:35 pm Post subject: |
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Just picked up a vac pump at Harbor Freight. They had two; a 2.5 & 3 cfm, with the 3 cfm being a two stage. I got the 2.5 one. Should I have spent the extra bucks for the 3cfm two stage? I will be using my old 5 gal tank for storage (I bought a new 7 gal aluminum one to replace the old one). Will the 5 gal tank be big enough? |
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IMMark Expert
Joined: 18 Nov 2010 Posts: 189 Location: Columbus, Ohio
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Posted: Tue May 08, 2012 3:32 pm Post subject: |
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Given what you mentioned on plastics, I think you will be fine with a 2.5cfm along with a 5 gal tank.
Get that puppy put together and start forming : )
Mark |
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captmike Novice
Joined: 01 May 2012 Posts: 27 Location: Elberton, Georgia
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Posted: Wed May 09, 2012 10:30 am Post subject: |
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After a day or two thinking about this and considering the input, I decided that for what I am trying to do I am just re-inventing the wheel. The toaster oven stuff will work, but to many parts and too much re-fitting. As suggested elsewhere on this forum, I took another trip to my local Wal Mart and looked at the grills. For my small project there are several to choose from. for $18 you can get a 20 x 14 flat griddle type grill, for $23 a 11 x 11 (approximate & my favorite) square skillet type and for $39 you can get one a little larger. All these have a circular element around the outer circumference of the pan, all have legs and would not have to be dissembled, depending on your platen/box size. My question, based on my platen size of 14 x 14 and thickness of plastic I will be forming is, will these, if properly boxed and insulated, get hot enough? ....update before I even post this! My wife had an old 12 x 12 skillet and gave it to me , so down to the shop I go and test the temps. |
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IMMark Expert
Joined: 18 Nov 2010 Posts: 189 Location: Columbus, Ohio
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Posted: Wed May 09, 2012 10:48 am Post subject: |
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I have never dealt with those, but honestly the plastics you mentioned should not take too much heat.
Also, FYI...a good place to look if you have a Goodwill store (or similar) you can find those type of things very cheap.
Mark |
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