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tigmusky
03-03-2008, 09:02 PM
I do alot of welding and fab at home, and no project is complete without paint. I have a small spray booth with filters but it's not vented to the outside because the fan so big that it will pull all the heat out of a 1600 sq.ft. shop. that's no good when it's 15`out. the booth work great for the over spray but, no so great for the fumes. What is powder coating ? fumes? over spray? home kit's worth a $#!% ? how much do that cost? does anyone have one ,likes -dislikes ?



thanks, daye

Junkman
03-04-2008, 12:44 AM
I had a fertilizer spreader that was powder coated, and it rusted away under the powder coating. I noticed yesterday that the powder coating on my tractor cab now has rust forming under the powder coating. My choice is paint, since it adheres better to the metal. I did have some engine parts powder coated about 15 years ago, and they have held up well. The trick with powder coating is that the metal needs to be sandblasted and totally clean for the coating to bond to the metal. If it isn't, then the coating will just go on and cover, but never adhere, allowing moisture to get under it forming rust. Problem is that by the time you realize what is happening, the damage is extensive. I would use paint over powder coating for most things.

oxycodone
03-04-2008, 01:16 AM
Powdercoat is typically tougher than paint. It's actually more like a plastic coating, and it's sprayed onto the bare metal then baked in an oven. I'm sure someone else can give you more details.

Bottom line is, it all depends on the application, exposure to heat and how you want it to look.

For example, on my black bike the tank, tail, fender and sidecovers are painted.
Frame, engine covers, wheels and swingarm (parts that need to have a tougher finish) are PC.

http://kawshed.com/black/036.jpg

comp
03-04-2008, 07:50 AM
I had a fertilizer spreader that was powder coated, and it rusted away under the powder coating. I noticed yesterday that the powder coating on my tractor cab now has rust forming under the powder coating. My choice is paint, since it adheres better to the metal. I did have some engine parts powder coated about 15 years ago, and they have held up well. The trick with powder coating is that the metal needs to be sandblasted and totally clean for the coating to bond to the metal. If it isn't, then the coating will just go on and cover, but never adhere, allowing moisture to get under it forming rust. Problem is that by the time you realize what is happening, the damage is extensive. I would use paint over powder coating for most things.

haven't seen :headscrat

riskyvt
03-04-2008, 08:08 AM
I do alot of welding and fab at home, and no project is complete without paint. I have a small spray booth with filters but it's not vented to the outside because the fan so big that it will pull all the heat out of a 1600 sq.ft. shop. that's no good when it's 15`out. the booth work great for the over spray but, no so great for the fumes. What is powder coating ? fumes? over spray? home kit's worth a $#!% ? how much do that cost? does anyone have one ,likes -dislikes ?



thanks, daye

Well, you're in luck! Getting into the handyman flavor of powdercoating is a breeze. I suggest if you're interested in seeing the results for small items, go out and find a used appliance sales business and buy an electric oven. Then buy a inexpensive powdercoating kit from HF, Ebay or Eastwood. Most will include a small amount of color powder. Like Junkman mentioned, the best prep you can do for powdercoated parts is a fresh sandblast. Small blast cabinets aren't that expensive.

Here's how it works:

1. Sandblast your part. Remove any kind of bearings, seals, gaskets....remember that this will be baked in an oven to cure the powder, so anything that will melt from the heat needs to be removed. Keep greasy fingerprints off it as you hang it from a rack of some sort, like with a small pc. of coathanger or wire.

2. The powdercoating "machine" will have a ground clip which attaches to the part, providing a negative charge. Turn on the unit and spray the powder onto the part, which is pulled toward it by the opposing charge. Overspray or too thick of a coat isn't an issue, the powder is self-leveling during the cure.

3. Put the part into your oven, careful to not jar it or touch the powdercoated surfaces. Bake in a 400-degree oven for 35-45 minutes. Remove and allow to cool.

4. ALL DONE! Easy as that....

Check out my '71 Pro Touring Chevelle website shown in my signature. Under the "Chassis, Suspension & Brakes" photo section, you can see a Chevelle frame that was coated in gloss black. Nice stuff! Good Luck. :thumbup:

bmwpower
03-04-2008, 08:09 AM
http://www.garagejournal.com/forum/showthread.php?t=14633&highlight=engine+build

Valve cover, upper/lower intake, thermostat housing, upper timing cover are powder coated.

VDubJoe
03-04-2008, 08:35 AM
Its all in the prep.Way tougher than most paints. Go to caswell.com and they have some very informative stuff. Ive got a cheap HF gun and an old oven. Works great. Im in the proces of building a 4x4x6 footer. Easy way to make a little side money,

Joe

HOTFR8
03-04-2008, 06:52 PM
I still prefer to use Jet Hot Coatings.

rsanter
03-04-2008, 08:18 PM
to remove the fumes you can make a 'waterfall filter' that will push the exhaust fumes through the 'water curtan' and let the water catch the fumes for you.

bob

tigmusky
03-04-2008, 10:04 PM
rsanter, I like this idea . I'am got to look into this.
:thumbup:thanks, daye

KCHOTBOAT
03-06-2008, 10:05 AM
The fumes are next to nothing. I did powder coating at home for a couple of years and no problem. Check out eastwood site for guns and forums. There are several places that sell powder in 1 lb bags and up. My first gun was a HF gun and it worked fine however if I was to do it again I would buy the eastwood pro gun which I believe is on sale right now. The better the gun the better results you will get with candy colors and objects with alot of detail.

Bib Overalls
03-06-2008, 09:40 PM
I get my powder coating done at a small shop that does industrial work.

http://flickr.com/photos/ratpoison/1937069324/in/set-72157601679531790/

I blast the small parts and do all the masking. They sand blast the larger items. I use colors that they have in stock. The items in the picture are "Bengal Red." Cost is less than materials for a conventional paint job.

There are shops that specialize in high end powder coating, custom colors, multiple colors, etc. They tend to be pricy.

I have done some small jobs at home with an Eastwood gun. I think you can get excellent results with one. But they are not suitable for large items. Valve covers and similar sazed stuff that you can get in a surplus home kitchen oven. Eastwood sells (or did) an infra red heat lamp system for larher items. I only know of one person who used them and he was very disapointed.

Kevin54
03-07-2008, 03:44 AM
1. Sandblast your part. Remove any kind of bearings, seals, gaskets....remember that this will be baked in an oven to cure the powder, so anything that will melt from the heat needs to be removed. Keep greasy fingerprints off it as you hang it from a rack of some sort, like with a small pc. of coathanger or wire.

You have to be careful as to what you sandblast with. Silica sand is a big "No-no" You want to use something along the lines of aluminum oxide or such. Just as in paint silicas, have no place. Proper prep is the key to powdercoating lasting.

PAToyota
03-08-2008, 12:40 PM
Ummm... There is a difference between silicone (the polymer - which can screw up finishes) and silica (which is related to silicon and is basically ground up quartz)... Completely different animals...

car99r
06-13-2008, 03:30 AM
I powdercoat at home all the time. I have been doing it for a couple of years. I use an Eastwood gun and buy all of my powders through eastwood. I bought some from ebay once and ended up with someones hairs in it??? I also just use an old electric oven that I have welded some racks in(although racks are not necessary).

Anyway, Be sure to have a very good clean surface (wear nitrile gloves). The cleaner sold by Eastwood works very well for removing any oils from your hands amongst other things.

Also remember that you do not want to bump the piece after putting the powder on and before placing in oven. Once in oven bake most stuff arund 450 degrees until powder starts to flow then turn oven down to 400 degrees for 35-45 minutes depending on the item. Thicker material you can preheat to help the flowing and coverage...

Sundance
06-13-2008, 05:07 PM
Just put my 2 cents in here. I have both the Harbor Freight and the Eastwood PC guns. I prefer the HF gun because it's a bit sturdier and it uses a foot switch instead of a hand switch as on the Eastwood. The HF model also has a stronger bottle for the powder. The Eastwood gun does have some different deflectors for the tip of the gun but I have never used them myself. They both seem about equal in the overall coating of parts. Thanks for letting me vent.

maje16
06-14-2008, 06:40 PM
I had a fertilizer spreader that was powder coated, and it rusted away under the powder coating. I noticed yesterday that the powder coating on my tractor cab now has rust forming under the powder coating. My choice is paint, since it adheres better to the metal. I did have some engine parts powder coated about 15 years ago, and they have held up well. The trick with powder coating is that the metal needs to be sandblasted and totally clean for the coating to bond to the metal. If it isn't, then the coating will just go on and cover, but never adhere, allowing moisture to get under it forming rust. Problem is that by the time you realize what is happening, the damage is extensive. I would use paint over powder coating for most things.


I work for a industrial ag finishing company, (contract for deere, case IH, caterpillar etc). I dont have any experience with the eastwood or HF type setups, so I wont comment on these. (we use Nordson industrial systems ($$$)) While the pro setups are second to none, hence the $$$, I cannot stress enough that surface prep is ultra important if you want any sort of corrosion protection. Most of the stuff that you buy (mowers, out door equipment etc) that is powder coated is hardly ever prepped adequately and will rust. We have incredible standards to meet for the industry that we supply for (ISO 9001)and test regularly with salt spray cabinets, powder coated mild steel and cast iron products consistently achieve 750-900 hours of saltspray testing before failure.(common testing involves scoring the painted surface to the substrate and subjecting the area to continuous salt spray solution until the coating starts to seperate from the substrate.) Im not sure how wet paint would compare to this , so I wont comment, i just wanted to point out that with the right surface prep, powder paint is an extremely good corrosion protector.
Oh by the way, surface prep can be vibratory, blast(aluminum oxide or glass) or phosphate treated wash, depending on material,requirements and application....
just my 2 cents....

Martin