oven question

[Fudd]

I have been playing with powder coating for a few months and have a couple of questions:

- Would it not be better to re-wire the stove elements to burn at the same time? Is there anything to watch out for when doing this?
- I also plan to build a larger oven (3'X3'X6') in the future and also wonder about elements: standard stove elements or I also have access to strip heater elements (220V 1500 watt). Which would be better?
- On the fan: How fast and what blade size? Where is it mounted and pointed?

Thanks,

Scott

[non-stick]

Fudd..... welcome to the boards.

As for ovens and sizes and elements,etc. Every flavor in the world is out there with more than quite a few schools of thought on the process. This seems to be a constant topic fo discussion with no right or wrong asnwers (where to place elements, how big an oven should I have,etc). One sees a myriad of answers posted because in essence, they are all correct in one way or another. The oven used for the hobbyist who finishes fly-fishing equipment will no doubt, be different from one that enjoys the hobby of coating motorcycle frames. Now should it be. If your needs meet or exceed 1500W elements and your parts are large, might I suggest an IR system perhaps? Caswell has a fantastic offering of equipment in this area for you to choose from. Are they good for EVERYHTING to be coated? I have to honestly say no.... but then again, a chamber type oven (the kind that you are referring to) isn't good for everything either. IR is good for a lot, if not most things and has it's advantages to whereas chambers also have thier strong points.

I'd seriously consider where you are going to be a hobbyist a couple of years from now (this goes for all of you) and see what your needs will be at that point. After all..... you don't buy a computer that "just gets the job done" in today's world, do you? I should hope not. You bite the bullet and pay for the good model that's going to last you for some time to come with no further outlay. The very same principal can be held in the powder coating world. If you see yourself using a lot of matte black, why order just the one pound from Caswell? Get a larger quantity and not only save in the long-run.... but make sure your needs are met in the future when you call for it. They are nothing more than "tools" that you should rely on. A toll to ensure you get the best product available to suit your needs in a finish. Powder, application gun and oven... they are nothing more than "tools". I've learned long ago to ally yourself with the best you can afford at the time as when you least expect it, the cheaply made tools (and companies.... no jab intended to the competition) will always let you down. This is why Caswell excels at it's business. Ask Dale how he was treated by Caswell when he was in a pinch. Caswell Inc is another "tool" for him to rely upon to get the job done right the first time. Your oven is no different. Figure out your needs and growth potential (all of you!) and write down what it should consist of. THEN you will actually have a blueprint of the direction you will need to take in assembling your equipment. I think you'll be quite surprised how often you all answer your own questions on this subject. Give it a shot and post it here with what you've come up with. I'd be interested in hearing how the needs vary from your original questions...... Russ

[11111111]

Russ can you tell us some of the differences in chamber cooking to IR systems. I thought you could not do both sides at the same time with IR. MOveable lights are much easier than a large oven. The shops around here only bake so I thought the lamps were only for a special need. What are the distances for the IR lamp and how many would it take to do say a sprint car chassis. Or a header, valve cover etc. I simply don't know much about the IR so if you can give me a widget example (Tube chassis) of how I would set up for this and how I monitor the process to completion I would greatly appreciate it.
I don't have many parts that would fit in a oven so I am very interested in anything that saves space in my work shops.
Jeff

[non-stick]

AHA! Somebody who actually *asked* for a widget example this time. I love the new guys, they havn't had it up to thier eyeballs with my widgets as of yet,lol.

Let's just focus on your immediate "pro's" and "con's" as a hobbyist, shall we? Often time we are limited in funds, space and ability. This is nothing new. One thing we have plenty of is time to play with all sorts of neat toys. This is a good thing to encounter on the IR path if you have large parts. Being a fellow car enthusiast, I see your plight. Perhaps you'd rather spend the thousands of dollars ( it could reach that high considering elements, controllers, wiring, insulation, metal, time involved, etc... or even the outright purchase of said "large" oven) on your car instead of an oven that takes up valuable space. One might even argue the point that maybe at the moment at least, you don't foresee yourself doing any more than 6 sprint car frames a year at best. This is where a manipulative system such as an IR source comes into play. The advantages are this : low cost, low storage structure, ease of use and lateral use within your coating shop for other purposes (they can be used to dry a part after phosphating rather quickly, or as a heat source if you have a cold garage and you need it momentarily near you). Disadvantages of the system include : tough work status if you intend to coat for everyday use, longer time spent on car frames and such compared to an oven because one must "move" the source around to get a cure, uncured portions of substrate due to the IR wave not being able to see around corners effectively. As you can see... you have some thinking to do.

We'll get back to your car frame in a minute. Let's flesh out your other parts first, shall we? For valve covers and the like.... I'd get a second hand used kitchen oven. It's not that you can't use the IR light without great results.... but I see them as an "add on" to the smaller ovens. Use the kitchen oven for the intake and valve covers, bracketry,etc..... use the IR for frames and parts that won't fit into the smaller oven. Chances are, you'll be using the smaller oven quite a bit, and the IR only once in a while. ( many small things on one car, only one frame per car,etc). Think of it this way.... a "marriage" of the two methods of heat, if you will. One is a smaller chamber and indirect so that it heats a given void of space, the other is direct and more focused. You can coat a bridge if you really desired to do such a thing. Now are you seeing how they both have thier purposes? Now... with that said, back to your car frame.....

An IR light only heats what it can see, as stated above. Therefore, logic dictates that if you can see it, so can the light wave. Where this comes into play on your tube chassis is this..... standard coat in say... matte black for example purposes. Position the IR light over the front section of the frame and you'll notice momentarily the cure process begin to take shape. Once a predetermined amount of time has passed (as dictated by your powder guidelines) you move the light to the next area and so on down the line until you part is cured. It may take a little more time this way, but I'm willing to bet you don't have the space or money right now to just go buy or build a large oven to fit it all. Another use for the IR that is an advantage is "on the spot" repair. Let's just say that you have a major coating failure in an area due to say.... you had to reweld in a new section from a hit. Well..... this is where an IR would be a lot better. As anybody here can tell you, to re-coat in an oven means sanding everything for adhesion and then coating it all over again. An IR light can simply be moved to said welded area and you can coat just what you need to without having to heat the entire mass. Pretty sweet,huh? When you're done with the lamps, you can just fold them up out of the way and save some space for something else without having to work around a big oven forever. Call it a "collapsable oven" if you will. It may take you longer for the overall cure, but you make up for it in square footage and money saved. Who knows, down the road if you find yourself doing more and more frames, you can actually get a bigger shop and build or buy that large oven. I whole heartedly endorse you to do just that if you have the means. The IR will still be there as a back-up and forever ready for those jobs needing touch up and such. (not to mention, a quite effective parts dryer after phosphating even after you have your big oven).

Personally, I recommend for your purposes, 2 of PRODM2000 listed on this page : http://www.caswellplating.com/powder/caswell_lamp.html or even one PRODM9000 and one PRODM2000 for your purposes. Set the lamps facing one another (in the M2000 instance) and the light refelcting into each other will negate and anything inbetween will be cured having been trapped in the midway. The fold easily and out of the way and lemme tell ya, you can't even compare the price between a huge industrial oven and the price of the IR's (2 ea. of M2000 cost 600 bucks). The gap between the two is just that large. We're talking thousands saved here as well as the above mentioned space. The only thing it costs you is a little extra time. But like I said... if that's even a huge factor, go for the M9000..... bigger work space = less time adjusting lamp position. Plug em in, use em, then move them out of the way. Quick, clean and cost efficient. All of the above holds true for your headers as well. Just hang them on something that will swivel and keep the lamp in one position. When one area is cured, rotate 1/4 turn, cured again, another turn. Keep doing that until you've rotated the part 360 degrees and it will be done. Typical distance for short wave IR is 12 inches, and medium wave is approx 16 inches from distance to part. Hope that helps answer your questions bud.... keep us posted as to what you finally settle on,k? .... Russ

[11111111]

Well it sounds like IR lights are definetly worth having. When I am under the IR lights and the peice is bigger than the light what happens to the powder coat in the over lap area.
I don't think I have ever used a IR light before. Can you bring me up to speed on how it works.
Also on my chassis how far out will the light reach to be effective and with these lights if you get to close does it change the operating temp of the surface that is being worked.
I was thinking that I can hang the chassis and place lights under and above and on both sides. This should eliminate any shadowing, will this work like a oven.
I usually do most projects a little overboard and error on the overkill side. But in this case I plan on doing just a few chassis's a year and most likely at about the same time and I would prefer not to use up such a large area in my garage with the oven.
Our actual race shop is about 35 miles from my home and I would certainly think that having the ability to make powder coat repairs their with out a total dis assembly and transfer to the oven at my work shop would be so much more conveninet.
I guess my big question is about the over lap in lighting when you move to the next section and how many lights would it take to make the chassis think it was in the oven that I was going to build so that it could be done all at once? Or is this necessary? I am truly green to this so all your insight is greatly appreciated. All the coating I have done to this point is with the hobby plating equipment.
Thanks
Jeff

[non-stick]

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

[11111111]

Thanks for the info Russ
Jeff

[Fireblade]

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.

[11111111]

thanks Fireblade

[11111111]

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

[non-stick]

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.

[Fireblade]

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!!!!!

[duke]

i'll drink to that
cheers

[duke]

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

[non-stick]

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.