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  • non-stick
    replied
    they shoot! they scooooooooore. I knoew you guys would have something fantastic to add to this. See that? VERY knowledgeable people here and I love every post ya'll make. Thanx,guys.

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  • DALE
    replied
    Okay where to start? Let's start with the lights, oven are readily available from hardware stores and they are easy to work with. I placed a pocket in the oven wall and placed these in the pocket with glass covering them. They are 110V and you can run them off of one side ofe the oven 220V so they require no strange wiring. My oven has a chamber built under the floor approx. 4 inches deep to house the fan motors available from grainger. Fans are 8" aluminum from NU-VU part number 50-0152 and they are $13.95 each. Fans can be purchased at 1-906-863-4401, they are bread proofer fans. Just be sure to get long shaft and 600 or less RPM motors that are open housing. The motors are below the floor where they receive very little heat. As for elements go for about 2000 watts each and start with four once the metal is all brought up to temp it should recover heat loss well. Be sure to have a min. of 2 inches of insulation but I recommend at least 4 inches. When you install elements leave room to add more if needed. If you wire them in paralell you can easily add more at any time. Hope this helps

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  • Fireblade
    replied
    Well just for ideas to give you elements can be either the household oven type, or industrial elements. Do a quick search on McMaster Carr or Grainger and you will see a few elements available. Each has different wattages they give off in heat, take different voltages, ie 120 or 240, and different thicknesses, which I am not real sure what that does. Maybe thicker they are the higher wattage they can offer, I forget right now. They run at a varied price, household elements, I think run about $40 bucks a piece and may put out about 2000 watts. Now picture this, say a 7' x 4' x 4' oven needs 16,000 watts to heat up and maintain 400 degrees at decent speed of temp rise. You would need 8 household elements to get the 16,000 watts, ie $320 bucks, plus temp controls and etc... The industrial elements would would cost less to do the same, but still need controllers, temp probe, etc... Building these is not a quick job, they take time and thought to construct correctly, so make sure you know what you are doing, or you will waste alot of money and have a pile of junk. I do not have pics of any of my fan setups, and to be quite honest, I still experiment and change the setup from time to time. My digi camera is broken and I need to buy another one, but I have other things I want more than that right now, so I am cringing and trying to forget about it.

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  • non-stick
    replied
    I gotta be honest with ya... I seel industrial ovens, not build them per-se. I see this as a classic "Dale" kinda post truth be known. How they should be used I'm good on, but I have no problem in yielding the floor where others are better at it. Sorry guys.... It's one of the many things I don't know about. Anybody else have any insight here? I'd be glad for the assist..... Russ

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  • Fudd
    replied
    How much wattage of heater elements are you using for a given size oven? Say a watts/cubic ft. I am looking to build a 3' square by 7' tall oven and use standard oven elements. Also I would like to install 2 lights. Any recommendations on the lights? I would also like to hear about how people have installed fans for circulation.

    Maybe non-stick should create a site to post oven plans and construction details. It looks like this a popular subject.

    Thanks,

    Scott

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  • non-stick
    replied
    visible when moving onto the next section to be cured,bud. First section will be "melted" and have flow to it... then it will start to get grainy and half melted, and then gradually to "powder" status. Once you move the lamp to the grainy section, the process repeats.

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  • duke
    replied
    nonstick, -- you stated in an earlier post that when using i.r. lamp on larger parts you can get overlapping.
    is this visible when cured or only before next section is cured?
    cheers

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  • duke
    replied
    i'll drink to that
    cheers

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  • Fireblade
    replied
    I have never personally seen the material you mention being used in building an oven. But I do know there are more way than one to do the same thing. You are thinking the same way as I with the fan mounted internally and the motor externally, thus eliminating any direct contact with an exposed spark. One thing I have seen, the fan, shaft and motor should not be directly linked with each other. The shaft will carry heat into the motor and possibly damage it, whether or not this is true I don't know. Most industrial units look to be mounted directly, so your own commonsense be used with this. As for elements, if you have enough airflow, the oven should be even heat all the way through, as long as you diffuse it somehow to be blown where the cold, somewhat remote spots of the oven are located. I think that is just something you have to play with and see what works and what doesn't. Heat rises, so in theory the top should be the hottest, the bottom the coldest.
    My smaller oven is just made out of 18 gauge sheetmetal, on a 1 1/2" angle iron frame, with 3/4" square tube making the frame for the oven itself. It has 3" insulation all around sandwiched between the inner oven walls, and the outer skin. All frame work was welded together.
    My larger oven is made of 4"x4" square tube, with 18 gauge panels, 4" thick walls. The reason for this monstrosity is I planned on moving it from the beginning, so I built it like a tank. My shop is just too small, and I plan on moving to a larger location for my work with PCing.
    Your idea on creating a multiple sized oven is a good idea, but you may run into some problems trying to circulate the air properly. Say your oven has 5 chambers, you have circulation running for a big piece using all five chambers. If you do a small piece and only need one chamber used, you airflow is going to be different. Maybe your rheostat idea may work, but I see you may be playing with that bit for a while to get it just right. Go for it, but make sure you really need it. Good luck

    P.S. ----- Non-Stick, as I said with the 100kv homemade gun, commonsense kicked in and I will buy one instead! lol


    And everyone, I must say non-stick is a huge help on this board for all involved with Pcing, Give him a hand!!!!!

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  • non-stick
    replied
    looks like I need to find a suppplier to have a "make your own" oven type of kit already pre-fabbed. I'd make a fortune,lol.

    also.... stop playing with the 100Kv powder supplies. I can tell you first hand they will knock you down if you get a zap! (we won't ask about that one,k? lol) Cheap is good.... as all can attest in here I'm the cheapest guy going. But safety? Oh nooooo.... no, we don't skimp when it comes to safety one bit. My life has no price-tag on it. Keep that in mind no matter what you decide or do.

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  • 11111111
    replied
    Fireblade,
    I had planned on installing a electric motor on the outside and running the shaft inside and then mounting the blade on the shaft. This would allow the use of a fairly in exspensive motor and with some type of reistat to control fan speed. I read somewhere on the commercial sights that they cycle the air through at 10 times the volume per minute. This seems awfully over kill? BUt with the reistat it will be easy to adjust.
    What did you build your oven out of? how thick are the walls and how much insulation did you use in the walls.
    I was worried about the elements possibly being to close to the part at some point so we had drawn into our plan to mount the elements to the side ( one element every two feet) and then place a piece of sheet metal over them to diffuse the burners direct heat from radiating directly on two the part. Basically a air gap. Our theory is that this would get the heat rising up the side of the oven and then with ducting and or fan we could force the air back to the bottom of the oven thus allowing a convection cycle and hopefully a very even heat through out the entire cavity of the oven.
    my plan is to make slots to slide a divider wall in at every two feet section to allow for heating of only the space that the part takes up and then to place a switch on every element so that I can shut down any section i am not using. also the section of oven not being used will have vent doors that can be closed to allow the ducted heat to by pass the unused section of oven.
    I am assuming that the oven temp regulator will be accurate enough? Have checked the unit in my oven and verifyed it to be very accurate at all temps.
    I have a friend that builds carbon fiber resin airplane propellars and he uses a heat controller that allows his oven to operate at + or _ tenths of degrees but he still uses oven elements.
    Quik note for a oven they use what looks like a insulation styro foam stiff board about three or four inches thick that is glued together and set over the molds after they are injected and then plugged in and the timers are set for the cycle which I believe is 325 or 375 for about an hour. These ovens are light weight and they use a electric carving knife to build them if they run into a need for a special shape. The ovens have no bottom in them and set on the concrete floor with the molds centered in them.
    Have you heard of any powder coaters using this type of material?
    Thanks for the info
    Jeff

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  • 11111111
    replied
    thanks Fireblade

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  • Fireblade
    replied
    I can offer some insight as to building your own oven can be like. I have 2 of them myself, one is 4' deep 2'6" tall and about 2' wide. Two elements, basic house oven elements, and to answer whoevers question it was, YES you can wire them up so both are on at same time. If you look at the wiring for a house oven, you have a 3 or 4 wire system, 2 hots and 2 grounds (4 wire), 1 ground (3 wire). The two hot wires are both 110v a piece, they are combined in your oven controller to divy (sp?) the power to where it needs to go. The top element is 110v the bottom 240v. Wiring them up together so far has not been a prob, so far! lol There is also a fan mounted in this oven, now let me say something here. I am CHEAP!!! If someone else did something or made it, so can I! I will build it before I buy it, don't think making a 100kv adjustable Pc gun hasn't crossed my mind and drawings. There is the theory again, someone built it, so can I! Commonsense has kept me from shocking myself to death. Anyways, like Non-stick said, if you are really not going to need the big oven on a daily basis, it does take a lot of space and money and time to make one. I have another that is not quite complete yet, 8' tall 4x4 wide and deep. It has been a on going project, and it is HEAVY, about 1400 pounds right now. No wiring, no fans, no electronics in it yet. You need help building something like this, and the tools to do it with. I have every tool known to man and it takes time to do it right, and safely. I have a IR light, but for my usage it is not something I need to use to do my job, I am much to busy to not have a large oven to do my parts. But when I did this stuff for fun and just my own parts, it was great. I put it away when I was done, and my shop was much bigger. Now you walk into my shop wearing full armor, and still run into stuff and hurt yourself. So there are ups and downs. Also the fan need to be intrinsically safe, they cost $$$$$. There are ways around them, but as I said, they take time to make and some thought involved. Either way have fun.

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  • 11111111
    replied
    Thanks for the info Russ
    Jeff

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  • non-stick
    replied
    having enough IR lights to make the chassis think it's in an oven is certainly not necessary. As stated above, the "overlap" is actually expected in an IR situation due to the fact that it can only cure "X" amount of space in a specified time. Just as a general rule, move the light within 12" of your part, watch for a flow of powder and wait 10-15 minutes.... then move the light onto the next area down where you see that powder "half-melted" and start the process all over again.... it flows, start a timer, and so on and so on. Like I said before.... if you want a process that's a little bit quicker, then subtract one of the M2000's and add an M9000 in it's place (larger IR surface) to cut time down quite a bit. Workable area is still the general space of 12-16ish inches away from the light.

    Let's take as a good example a past customer of mine that only did lock down rings for truck tires ( they go on rims that can be broken down). I had him hang them on a line with a bank of about 12 IR lights and it moved at approx. 4 feet a minute. Coat them and as they move throught the "chamber" they cured. The lights faced one another and then when the parts came into "view" the cure process started. As the part moved through the IR bank, they cured and then exited. Approx distance from part to light was 14 inches. He coated rings ALL DAY LONG in this fashion. Pallets full of lock down rings left the facility and his "IR oven" space was no wider than that which you would walk on and about 10' long, tucked up against the side of the wall. From blast to packaging, his whole entire coating area took up about the space of a common one car garge. THAT is making the most of your space! More importantly.... THAT is what IR lighting is all about...... a lot of heat concentrated in a tiny amount of area. In your instance.... the IR will be folded up and moved out of the way for precedence to use as a mechanical area I'd assume.

    To answer another question, yes.... the closer yo get, the warmer your temperature. Effective range is 12-16ish inches as stated above. A good general rule of thumb is 12"= 425 degrees, 14" = 375, 16" = 325 and if I were to use as a heat source (such as if I were working in a cold garage and had no alternative heat) I'd have them several feet away from me to keep me warm. Keep in mind, when using these lights for coating purposes..... these lights heat the metal as well and not just the powder coating. So if you have say.... we'll use my infamous widget example for this one, a piece of 36" X 36" by 1/2" thick aluminum widget..... the heat transferred from the operating side would most assuredly travel through to other parts of the widget and cure to some degree, beyond the "view" of the IR (backside or farther out on the piece as expected).

    ""I don't think I have ever used a IR light before. Can you bring me up to speed on how it works."" ..... sure you have. ever eat french fries from a fast food place? Your food was kept warm by a very weak version of that very same IR. They are not one and the same as far as coating and curing your powder go (that question was raised not all that long ago here) but the principal is the same. Those lights are of a "long wave" format. Think of big long gentle waves on a calm ocean.... not to much to speak up in ways of activity.... but the water is in fact, moving. Now.... think of a typical day of surf at the beach.... you can go in the water but there's no doubt water is moving at a good pace. This is medium wave. Now.... think of a bunch of power boats on a lake and the wake left behind them....now multiply the height of the wake by a little bit. Fast movement in bursts of wave..... but they always seem to lose value by the time they hit the shore (a great distance away)..... that is like short wave. Long wave travels farther... but not much "oomph" to really write home about, or in this case..... heat to get your part cured. This is why your french fries don't automatically get burnt as opposed to just stay warm. Medium wave is a typical day at the beach, so to speak. A good focus of waves and just enough concentration to get you wet and have fun to boogie board on for a while, but not forever. Lastly, we have the races on the lake. Fast and agressive.... water (or IR light in this case) moves rapidly and you'll most certainly perform acrobatic stunts if you jump over them with a pair of skis close enough. Will they make it to shore? Nope..... intensity that great never lasts for long and you have to be "in the sweet spot" to enjoy it, per se.

    Medium wave light is a good "all around" system to use. If you don't have a good amount of time to deal with the compact size of the M2000, get one M9000 and mate it along with one M2000 as stated earlier. The M9000 can be on the outside of the chassis while the 2000 can be directly opposite it inside catching what the bigger one doesn't "see" as a boost. If you are *just* redoing welds or small parts of some such... I'd suggest the S2000 due to the fact that it's like the power boat example.... but you are doing frames. Good for a valve cover maybe... but not for a large suface area such as yours. The goal is to mimic a large oven, after all. Personally.... if it were MY money, I'd get one M2000 and one M9000 just to cut down on the time factor and growth potential in the future. But that's just me.

    Hope that answered some of your questions...... Russ

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