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Hi All,


I am shopping around for a good curing lamp at an affordable price. I see the prices range from $150 (eBay) to $1000+ (Eastwood). I am powder coating engine parts and wheels. I'll be doing this no more than once a week. I've got the 110 volt set up in my garage.


I am not necessarily looking to go the cheapo route but don't want to overkill either. Would the lower priced-stuff be okay (sub $250) or are there quality/reliability issues I should be concerned about? Any particular brands that you recommend or warn against? Any other advice is also welcome and greatly appreciated.


Thanks in advance,
 

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Powder coating heat lamps

Sounds like you are planning on doing heavy parts - wheels and such. Durable powder coatings need at least 350 degrees f metal temp for at least 20 minutes. Infra red heat lamps cure from the outside in and will require less time and does not have to heat up the metal to cure the powder. Main issue is if it is under cured, it will be very brittle and chip very easily.
 

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The wattage required is going to affect the price as well..too small a lamp will take too long and may result in an uneven cure.

Sam

moving to garage tools
 

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"But how do it know?"
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Discussion Starter #4 (Edited)
Hey 31Vicky,
31Vicky said:
Sounds like you are planning on doing heavy parts - wheels and such. Durable powder coatings need at least 350 degrees f metal temp for at least 20 minutes. Infra red heat lamps cure from the outside in and will require less time and does not have to heat up the metal to cure the powder. Main issue is if it is under cured, it will be very brittle and chip very easily.
I'm looking at powder coating things like wheels, intake manifolds, alternator housings, etc. I can't see myself powder coating anything bigger than a transmission or a rear end housing.

I have been using a dedicated electric oven from Harbor Freight but hit my limitation recently when I couldn't fit an intake manifold in there. So I figure its time to invest a curing lamp. Going by what you say, the infra red type is the way to go, and they seem average around $300.




Hey Sam,
OneMoreTime said:
The wattage required is going to affect the price as well..too small a lamp will take too long and may result in an uneven cure.

Sam

moving to garage tools
Thanks for moving it. I couldn't figure out what the right place would be for this.

Would you be able to give me an idea of what kind of wattage I should be looking at? I have seen quite a few of them in the 1500-1650 watt range. Here is one that I found: Infratech. Its listed as the number one selling portable lamp and $173.99 + free shipping = attractive price.




Got some more questions: What is the difference between short wave and medium wave? Is the thickness of the metal an issue as well?




Thanks for the helpful tips guys! :thumbup:
 

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the 'Duracell Project'
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i used an old 30'' oven for powder coating my 15x8 wheels
anything that will fit in there can get powder coated

i got it free, stripped out the range burners and run it on a 20 amp 220 circuit.
i have a infrared thermostat that i used for checking temps,
but now just set the oven thermostat @ 450f, when the thermostat kicks out
i look for flow out and then turn the thermostat down to 400 for baking.

i made a wheel fixture for powder coating them, basically a hub and bearing on a flat plate.
i put the wheel on the fixture with the rack pulled out,
line the door with cardboard and powder coat the wheel,
spinning it on the fixture, gently slide the wheel and rack in and bake it.
open door, cool, flip wheel and repeat.
 

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"But how do it know?"
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Discussion Starter #6
Hey ogre,
ogre said:
i used an old 30'' oven for powder coating my 15x8 wheels
anything that will fit in there can get powder coated

i got it free, stripped out the range burners and run it on a 20 amp 220 circuit.
i have a infrared thermostat that i used for checking temps,
but now just set the oven thermostat @ 450f, when the thermostat kicks out
i look for flow out and then turn the thermostat down to 400 for baking.

i made a wheel fixture for powder coating them, basically a hub and bearing on a flat plate.
i put the wheel on the fixture with the rack pulled out,
line the door with cardboard and powder coat the wheel,
spinning it on the fixture, gently slide the wheel and rack in and bake it.
open door, cool, flip wheel and repeat.
The oven idea sounds great, actually. Used ones are going on Craigslist for the local area for about $100. It'll keep the dust out. And the setup you described for the wheels is very useful. My issue is the space needed. I guess if I ditched my current oven, I can make it work. The other thing I'm thinking about is that if I ever had to powder coat something that is unusual in length or size, the lamp would have me covered.

Any thoughts?
 

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I did the exact same thing.. Free oven. Stripped the burners out.. 20amp 240 circuit.

A light would be beneficial for giant parts though.
 

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powder coating oven

IR overs come in short and medium wave, the short wave cure the fastest but are very sensative to distance from the object. A deep dish wheel would be a problem - over cure (loss of gloss and yellowing) on the rim and undercure (chipping problems) on the inside. The medium wave is better but is more like a regualr oven, needs more time and heats the metal to cure. Still a little bit of problems with line of sight curing like short wave. If light can not see it, no cure takes place.

The old oven from Craig's list is a great idea if you can get your parts in it. They will work very well. Most urethane powders bake at 350 for 20 minutes, wheels and heavy metal may take 30 to 45.
 

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"But how do it know?"
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Discussion Starter #9
31Vicky said:
IR overs come in short and medium wave, the short wave cure the fastest but are very sensative to distance from the object. A deep dish wheel would be a problem - over cure (loss of gloss and yellowing) on the rim and undercure (chipping problems) on the inside. The medium wave is better but is more like a regualr oven, needs more time and heats the metal to cure. Still a little bit of problems with line of sight curing like short wave. If light can not see it, no cure takes place.
That' s a very helpful breakdown.Thanks! :thumbup: So, long wave is the way to go. Out of curiosity, for proper curing, two lamps set at opposites may provide the best results?




JohnnyK81 said:
I did the exact same thing.. Free oven. Stripped the burners out.. 20amp 240 circuit.

A light would be beneficial for giant parts though.
31Vicky said:
The old oven from Craig's list is a great idea if you can get your parts in it. They will work very well. Most urethane powders bake at 350 for 20 minutes, wheels and heavy metal may take 30 to 45.
Im thinking of buying an oven off Craigslist, as well as the Infratech lamp in case I need to powder coat some odd-sized item. The portability would be nice too. This setup should have me covered for pretty much everything.




Thanks guys for all the help! :thumbup:
 

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Powder infrared ovens

One on each side for sure. Remember distance from part needs to be uniform for proper cure. Not as critical with long wave.
 

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I'm in agreement with the previous posts that suggested that convection ovens are preferrable to IR for curing powder coatings. I vastly prefer convection cure for quality purposes, especially for one-off parts and complex mixes of shapes and sizes. I'd also suggest investing in either an infrared pyrometer, or a thermocouple, or some temperature indicating crayons in order to be able to monitor substarate temperature.
 

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"But how do it know?"
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Discussion Starter #12
Hey powderbill,
powderbill said:
I'm in agreement with the previous posts that suggested that convection ovens are preferrable to IR for curing powder coatings. I vastly prefer convection cure for quality purposes, especially for one-off parts and complex mixes of shapes and sizes. I'd also suggest investing in either an infrared pyrometer, or a thermocouple, or some temperature indicating crayons in order to be able to monitor substarate temperature.
Well, then I've got some further researching to do. :)

I am not familiar with convection ovens and substarate temperature. Im going to google these terms right now. But if you or anyone else can explain these in laymen terms, I and future readers who stumble on this thread would greatly appreciate it. :thumbup:

Thanks for the continued help! :thumbup:
 

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IR Ovens for Powder coating

Ok, will give it a shot. Convection ovens are like your wife's oven in the kitchen. It heats the air and the air heats the parts. With powder coating, depending on the type, you need heat to cure. Epoxy cures at room temp, but at a snail's pace so heating it to 250 degrees f is the normal cure temps. Urethane's need about 350 to 400 to cure. When I say 250, 350 or 400, what I mean is metal temp needs to be at that point, not the air around it. So when you are heating a big heavy part, it takes a long time for it to come up to a temp that it will cure at. Urethane technology has to get above 330 before it can do anything. Metal has to stay at that temp for at least 10 minutes at the higher temp and up to 30 minutes or longer at the lower.

Convection ovens cure from the inside out (metal side to air side). IR is a different animal. 3 types short, medium and long wave. Long wave heats metal just like convection, medium is a combination version of short and long wave. Short wave cures from the outside in, so it just heats the coating, not the metal. This shortens cure time. Can do coatings in 5 to 7 minutes or even less ( I have had some that cured in 6 seconds). Problem is that it is a light. Light is line of sight. If you can not see it you can not cure it. It also is dependent on distance. An object 1 foot away will cure faster than one at 18 inches. So if you have a complex part, it could cure in some places and not others.

Having said this, there a combination ovens that use both IR and convection - IR to get it started and convection to finish it. Also there are high air flow convection ovens that "scrub" the part with very hot air to shorten cure time.

Hope this helps you understand the process. I come from almost 40 years of coatings experience working with all kinds of technologies on production lines as well as formulations.
 

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31Vicky's comments are right on track, and I think he's already explained it well. But if lt1 or others have further questions on the topic, just ask and I'll try to explain further.
 

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i have heard of guys building a metal 4 sided box (top and 3 sides) that fits onto the front of the oven so they can use it with the door open for bigger parts


what powder coating system are you using and how well do you feel it works?

this is something i have wanted to start doing for a long time

i had a guy, but he sold his business, and the new owner, after some very bad experiences (long story) could'nt pay me to coat my stuff :mad: :boxing: :mad:
 

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Discussion Starter #16
31Vicky, that is an excellent breakdown. I couldn't have asked for a more simpler explanation. You've clearly know your stuff. Thank you so much! :thumbup:

powderbill, thanks for sticking around this thread in case we have any more questions. :thumbup:




Hey Matt,
matts37chev said:
i have heard of guys building a metal 4 sided box (top and 3 sides) that fits onto the front of the oven so they can use it with the door open for bigger parts
Thats interesting. I would think it would be a five-sided box to keep the dust and cold air out.




matts37chev said:
what powder coating system are you using and how well do you feel it works?

this is something i have wanted to start doing for a long time

i had a guy, but he sold his business, and the new owner, after some very bad experiences (long story) could'nt pay me to coat my stuff :mad: :boxing: :mad:
I am using Eastwood's Elite HotCoat Powder Coating Kit. To me, it seems like a good starter kit with the gun, some basic colors, plugs for holes and a guide book. I have only used it twice but I feel it works well. I have powder coated a set of wrenches and a carburetor and they came out pretty good, in my opinion. The system has very good reviews online as well.

The system isn't difficult to use at all. As long as the compressor is up and running, the gun is properly grounded on the part and there isn't too much powder in the bottle, things go rather smoothly.

Now that I am considering doing things like valve covers with the raised letters in different colors that the covers and whatnot, I am having to learn how to properly mask parts and properly cure the two different colors.

One of the things I have not figured - and I hope someone can chime in about it - is how to powder coat a part that is hanging from the wire, but the wire is covering a part of it. This is not a problem if the wire is in a place where the part won't be coated. But for something like wrenches, there will be that small section that won't be painted because the hanging wire is on top of it.
 

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Wire blinding part of the part

What you have discovered is called the"fariday cage"effect. What this means is this-powder coatings are electostaticly applied. You put a charge on the powder and ground the part so the powder is attracted to it. The powder will take the shortest path to grounded metal, which in you example is to the wire leaving a blind uncoated area behind it. Only way to avoid is to hang part different.
 
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