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Hey all,I need to build a 2' x 1.5' x 1.5' project oven that holds a 225* temp and plugs into a 110v socket.I'm in the planning stages so I need some ideas on:1) heating element2) temperature control3) insulation material?4) outer structural materialThe ideas I had were:1) 110v adjustable hot plate (for boiling water etc)2) the adjustability might take care of this, but not sure what to do if it doesn't. thermostatic 110v switch?3) I have no idea... 4) naturally I want to weld something up, so maybe 14 gauge mild steel sheet?
Reply:Whats its for, powder coating?Ya gotta spend money to make money!
Reply:Sounds like a powdercoating oven - there are lots of plans online. Most that I've seen at that size use the heating element, and controls from a scrap kitchen range / oven. Given the low temperature you need and the small size, I'm thinking you might also be able to get away with a toaster oven element / control provided it was well insulated.This build has excellent detail on design considerations and construction methods.He spent $300, but yours is much smaller, so you should be able to cut the cost...
Reply:Taiden....You could go to wal-mart an pick up one of those toaster-ovens, for like $25 or$30 bucks an redo as you needed.You would have a heating element, thermostat, an even a timer. Thats just one idea.In the words of the great philosopher Quagmire.Gigedy Gigedy Gigedy Gigidey Goo.
Reply:lol....i was a little late on the typeing.In the words of the great philosopher Quagmire.Gigedy Gigedy Gigedy Gigidey Goo.
Reply:actually it's for heating up headlights, I do HID retrofits and I heat them up to soften the OEM sealant so I dont crack the lenses trying to open them. That's why no hot spots are important, I can't afford to melt any plastic.Can you powdercoat at 225 fahrenheit? If so, it looks like I might have a multipurpose machine
Reply:Oh, I'm a big fan of the toaster oven idea... I bet I could find a used one kicking around in a good will or something.
Reply:Toaster oven.You probably won't even have to buy one.People throw them out all the time because theyare dirty.I built an electric smoker out of one.Is this project temperature critical?You may want to monitor the temp. with something else(multimeter w/thermocouple probe,etc.)at least until you can verify temp. settings.Miller a/c-d/c Thunderbolt XLMillermatic 180 Purox O/ASmith Littletorch O/AHobart Champion Elite
Reply:Throw some wood chips and meat in it and you have yourself a smoker.
Reply:Oops- more slow typingMiller a/c-d/c Thunderbolt XLMillermatic 180 Purox O/ASmith Littletorch O/AHobart Champion Elite
Reply:temp should be between 200* - 225*, never exceeding 250*
Reply:Sounds like a cool project. For powder coating you need around 350-400. I've got a little toaster oven (out of the trash, of course) that does that easily.I've also got an actual kitchen oven, (also out of the trash) that works fairly well for powder coating. It's a little small for the things I want to start powder coating, but at least it's bigger than my toaster oven. It would work pretty well for a couple of headlights.I'm going to be building my own oven for powder coating as soon as time/space/money/necessity/planetary alignment allows.Some of the ideas I've come across online consist of using concrete backer board for the walls, metal studs for the frame, and either fiberglass insulation and or that blue insulation foam that's sold in sheets.Anyway, a little toaster oven will do about 500*. If you take the heating elements and controls and put them in a box that's 2'x1.5'x1.5', I bet you'll get your 200*-225* temp range easily.Whatever you do, let us know how it turns out.
Reply:I've done a lot of headlight retrofits & personally am not much of a fan of the oven method... it puts too much heat into the other components & if your not real careful you will wind up with discoloration or even micro crazing of the lenses among other problems like inner fulcrums & pivots becoming brittle, man times the heat damage doesn't even show itself until your done & put the light back into service... I use a heat gun & pass it over the seem continually, keep it moving & put enough heat into it to heat soak the seam enough to soften the sealer... average headlight takes all of ~4 minutes to open without damaging anything... the amount of effort you'd put into perfecting an oven technique isn't worth it unless your planning on doing huge volumes like cincity or something, I'd suggest trying a good heatgun first...miller 330a bp TIGmiller dynasty 200DX TIGmillermatic 185 MIGthermal dynamics cutmaster 101 plasma cuttersnap-on YA5550 plasma cutterhypertherm powermax 30 plasma cutterbaileigh CS225 cold sawetc....
Reply:Keep in mind that cookin oven and toaster oven temperatures are "average overall'. The heat up pretty high then shut down and let temps drop quite aways before turning back on again, plus the temps at the top can be quite a bit higher than temps at the bottom.In short I'd question whether their regulation is accurate enough for critical work."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Originally Posted by turbocad6I've done a lot of headlight retrofits & personally am not much of a fan of the oven method... it puts too much heat into the other components & if your not real careful you will wind up with discoloration or even micro crazing of the lenses among other problems like inner fulcrums & pivots becoming brittle, man times the heat damage doesn't even show itself until your done & put the light back into service... I use a heat gun & pass it over the seem continually, keep it moving & put enough heat into it to heat soak the seam enough to soften the sealer... average headlight takes all of ~4 minutes to open without damaging anything... the amount of effort you'd put into perfecting an oven technique isn't worth it unless your planning on doing huge volumes like cincity or something, I'd suggest trying a good heatgun first...
Reply:what headlights do you specialize in? or do you do many different types? personally I do mostly infiniti fx headlights, been doing a dual projector modification on these, I even built a vacuum chamber for mold making & cast my own clear side marker reflectors which turned into a huge pita... I'd like to see some of what your doing in there miller 330a bp TIGmiller dynasty 200DX TIGmillermatic 185 MIGthermal dynamics cutmaster 101 plasma cuttersnap-on YA5550 plasma cutterhypertherm powermax 30 plasma cutterbaileigh CS225 cold sawetc....
Reply:Originally Posted by SandyKeep in mind that cookin oven and toaster oven temperatures are "average overall'. The heat up pretty high then shut down and let temps drop quite aways before turning back on again, plus the temps at the top can be quite a bit higher than temps at the bottom.In short I'd question whether their regulation is accurate enough for critical work.
Reply:i know you wanna weld up a box...and maybe im crazy...but if its only going to 250 degrees make it out of wood, which is an insulator and burns at over 400 deg
Reply:Originally Posted by weldbeadi know you wanna weld up a box...and maybe im crazy...but if its only going to 250 degrees make it out of wood, which is an insulator and burns at over 400 deg
Reply:This might be a piss poor idea, but if you need it to be a specific temperature... Say 225F and leave it there and not worry about it fluctuating temperatures too much you should use something that absorbs heat easier than air and will stay where you leave it. Do a couple of experiments with a hot plate and control the hot plate with a thermostat in the water....Then you'd eliminate the chances of hot spots and be able to clean off the headlight assembly easily. If this doesnt make sense it's because I'm exhausted -JoeI can remember in the 7th grade my mom said "people will offer you drugs" by the 10th grade I was like, "where the hell are these people?"
Reply:not much useful input on the other stuff, but if you want to avoid / reduce hot spots.....a circulating fan might help distribute the heat by mixing the air in the oven. my toaster oven has this....makes a killer grilled cheese
Reply:Looks for a used camper oven. Or look for a big toaster oven.
Reply:Convection ovens use a fan to circulate air in the oven, and those are/were used in more expensive homes that tend to throw out useful apliances before they wear out.(the only difference between a normal and a convection oven is that fan)
Reply:Here is an oven I built for potting electronics:http://www.aprsworld.com/gallery/shop/IMG_7386$40 Target toaster oven. Stripped out the control electronics and replaced with a PID controller and solid state relay.
Reply:If you have it I would go to 220-240 volts save the amps. What wattage element do you plan on using?Oh wait you need help on that.Sorry, I dont know any companies that make them.Last edited by pyroracing85; 11-08-2010 at 11:49 AM.Hey kb0thn, that's amazing. Do you have a link to a build thread on that?I was looking at PID controllers online and they seem to all be upwards of $200.I'm trying to spend less than $100 when all is said and done.Do the PID controllers use PWM to control temps instead of using an on/off thermostatic switch? Seems like that paired with a convection fan inside the oven would make for pretty darn accurate temperatures.
Reply:PID controllers use a relay to turn on and off a heating element of air conditioning, in terms of a heater it may cycle on for 1/10 of a sec and be off for 9/10 of a second. The PID controller varies these times to achieve a steady temperature, longer cycles for a larger heated environment.3 things for a controller than can keep an oven at 225+-.1F for ~$50:Sestos PID Controller on eBay25 amp Solid State Relay on eBaypt100 Thermistor on eBayThese exact components can be used as part of a sous vide cooker as wellhttp://cgi.ebay.com/New-PID-Digital-...item4aa6c54304http://cgi.ebay.com/SSR25A-SOLID-STA...item19c1430081http://cgi.ebay.com/Thermocouple-Tem...item3cb2fc18f7I would make a temperature controller box that you can plug anything (brew heater, sous vide, powdercoat oven, smoker...) into along with the temp probe and therefore control its temp exactly. this PID controller has an auto-tuning functionLast edited by slopecarver; 12-02-2010 at 02:40 PM.
Reply:slopecarver, before I bid on these items (im' about to whip out the paypal account since you sent those links) I have a few questions1) could I build the controller so its just inline with the wall socket plug for my toaster oven, then fish the thermocouple inside2) is that PID controller the right one? It says it has 1 relay output, they have another model that has 1 solid state relay output. would I want the SSR output one instead?3) do you have any suggestions for materials for making the enclosure?
Reply:would 212 degrees be close enough? would it be possible to do something on a double boiler idea where the you heat water in the outer vessle and heat your headlight in the inner vessle? no need for complicated circuits etc just need to remember to add water.
Reply:I thought about that, the only issue is I really do not want to do it because headlights have to be dry when you reseal them, and the oven will be used to reseal them. introducing any kinds of moisture early on will increase the chance of fogging issues for customers later down the road.
Reply:just a side note now that you mention moisture, but it's a really good idea to pick up some tiny desiccant dryer packs, the kind used in shipping & packing to eliminate moisture damage & glue one or 2 inside each headlight... a little moisture buildup can be almost normal & the desiccant dryer packs will absorb it & not let the lenses fog up at all, it's self renewing from the heat in use... just a little trick some of the bigger headlight guys have picked up on...miller 330a bp TIGmiller dynasty 200DX TIGmillermatic 185 MIGthermal dynamics cutmaster 101 plasma cuttersnap-on YA5550 plasma cutterhypertherm powermax 30 plasma cutterbaileigh CS225 cold sawetc....
Reply:yeah, i currently use desiccant packs as a backup plan... but the less moisture i start with, the happier I am.
Reply:Watch out for the hot plate idea. I used one in a smoker and I melted the plastic bits out of it. An old school, all metal one would be OK, but new ones won't last. I ended up canibalizing an old 220v stove for the oven elements and the top burner. I chopped out the stove top that holds the burner and used high-temp wire (from appliance repair store) to rewire it. I re-used the stove knob for the round burner. Purchased a thermostat to run the oven element for a majority of the heat. This will run 110v also. Works pretty well. http://www.alliedkenco.com/catalog/p...roducts_id/781
Reply:Originally Posted by TaidenI thought about that, the only issue is I really do not want to do it because headlights have to be dry when you reseal them, and the oven will be used to reseal them. introducing any kinds of moisture early on will increase the chance of fogging issues for customers later down the road.
Reply:That PID controller has a SSR(Solid State Relay) inside, however it is only rated at 3 amps (it takes circuit board voltage and ramps it up to something more usable which could directly control something of a lighter duty, not a 1000W+ heater, for that you need another SSR rated for more amps. For the enclosure just weld up a box, you have those capabilities correct? The assembly would be built into a project box of some sort. plug the assembly into the wall, plug the heater and thermistor into the assembly. I say plug the thermistor into the assembly because you could wire it to a stereo headphone jack and wire a port into the box. Not shown on the back of the box is a small ventilation fan and a power port like what you would see on the back of a desktop power supply.Cool thing about the entire setup it that it could be wired up to control something running on 220, such as an old oven rated at 5000W, assuming you got an adequate SSR.Last edited by slopecarver; 12-02-2010 at 11:56 PM.
Reply:Thanks slopecarver. I'm ordering those components today. I just need to figure out what I'm going to make the larger oven enclosure out of.
Reply:Ended up winning this today, shipped with thermocouple for $33.00http://cgi.ebay.com/ws/eBayISAPI.dll...#ht_4826wt_938
Reply:I learned a few things about my PID controller that may help you, the relay output just turns on or off the continuity between the posts, I had thought the output was actually a voltage output that I could hook directly to the SSR, but apparently not. I had to wire mine so that it switched the output of a phone power adapter to turn on and off the SSR. If you have any questions about programming it shoot me a PMI have used mine to cook a top loin steak at 133F for 2.5 hrs and it came out as tender as a fillet and medium rare all the way through, I seared it on the stove top ribbed griddle to caramelize the exterior a bit. Right now it has been cooking a brisket for about 18 hours.
Reply:I use a Ranco ETC 111000 digital control for smokers up to 200 degrees. About $50.00.Grainger has a digital controller that goes to 300 degrees for $95.00.http://www.grainger.com/Grainger/CON...JN0?Pid=search
Reply:I am setting up a Kiln for heat treating metal. I just got in the 240v 50a solid state relay. It is pretty much ready to make the metal box to mount everything. It is all done with an OOPIC which is similar to a basic stamp and a type K thermocouple. I programed it to where you input:Climb (heat up) fast, or slowPeak tempHow long it holds at the peak tempReview settings and runThen monitors cool down and flashes a group of LED's when done |
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发表于 2021-8-31 23:44:12