powdercoating

[undercnstrction]

i know this topic has been brought up before but when i did my search there wasn't anything that turned up that seemed to get into much.

i finally picked up an oven on saturday for the sole purpose of powdercoating.

1) which guns do you guys suggest for someone that is not going to be doing this as a full time gig. i've seen guns from harbor freight (and have read some good reviews about it) and seen a kit from eastwood (also good reviews). i'm told the HF gun is a better quality setup....any opinions there?

2) where is a good place to buy colors from that doesn't charge a mint for them and has a good selection and good customer service

3) for you guys that have done this before, can you offer up some do's and don'ts and/or a good site that has good info for the DIY

4) i have a number of pieces on my boat that i want to re-do. they are currently coated (i don't believe it's powdercoat though, i think they are anodized). what's a good method to strip them? sandblast? chemical?

5) prep work for non-coated pieces (bare aluminum/steel)?

thanx for the input......

 

[Tanus]

my buddy has a huge oven in his garage, done a bunch of motorcycle parts for me

4.have to sandblast them, media you use depends on material being stripped

5.very clean, with I light scuff, like 600-800 grit.

 

[Ozz]

i know this topic has been brought up before but when i did my search there wasn't anything that turned up that seemed to get into much.

i finally picked up an oven on saturday for the sole purpose of powdercoating.

1) which guns do you guys suggest for someone that is not going to be doing this as a full time gig. i've seen guns from harbor freight (and have read some good reviews about it) and seen a kit from eastwood (also good reviews). i'm told the HF gun is a better quality setup....any opinions there?

2) where is a good place to buy colors from that doesn't charge a mint for them and has a good selection and good customer service

3) for you guys that have done this before, can you offer up some do's and don'ts and/or a good site that has good info for the DIY

4) i have a number of pieces on my boat that i want to re-do. they are currently coated (i don't believe it's powdercoat though, i think they are anodized). what's a good method to strip them? sandblast? chemical?

5) prep work for non-coated pieces (bare aluminum/steel)?

thanx for the input......

1) For a hobby gun, an Eastwood, Caswell, or Harbor Freight gun will do you fine. I've used the EW and HF and to be honest both can get the same results on most parts that my expensive Nordson gun can. The Nordson system has more capabilities but for 90% of the things I do, I don't even need it.

If you're interested in an EW gun I've got a brand new one, never used...

2) I get my powders from Caswell Plating, they carry Tiger Drylac which is one of the top powder companies. Great stuff all around. Eastwood is good too but I think Caswell is a little cheaper. Powder Buy The Pound | Powder Coating Equipment and Supplies is also good but tend to be more expensive. Not sure who their powder mfr is, but it might be themselves

3) Caswell Plating and Eastwood both have forum sections of their sites which are helpful. I can help you out on here, too. It's quite basic. It can be as easy as: blast the part clean, hang it from a hanger bar, attach the control box cord to the bar you're hanging parts from so the part will become static charged, hook up ~5-10 psi of dry air to your gun, and pull the trigger. Each box also has a trigger that you depress to 'turn on the voltage', so the powder will be drawn to the part. For the EW gun you hold a trigger in your free hand, press the button, and shoot the powder. The HF gun has a foot pedal. Both have their merits.

4/5) sand/media blast is my only way. Blast 'em clean, blow them off, shoot them with powder. It's that easy. You can do other steps in between too.

I don't trust the chemical cleaners to do it and I don't have interest in stripping parts just to do it 'the right way' all over again. You might be able to coat over the anodized parts but you'd have to chemical clean it anyway so it's ready for powder. Dirt & dust will cause problem when you cure the parts.

 

[undercnstrction]

thanx a TON for the insight.

mansonozz, i sent you an email.

 

[Ozz]

I didn't receive anything, can you PM it to me?

 

[undercnstrction]

sure, i'll send it shortly.

where do you recommend buying supplies from? high temp tape, the plugs and caps, etc, etc. i'm sure there is a local supply house that would carry of this stuff but if you buy from a certain place that has smokin' prices, i'll hit them up too.

 

[undercnstrction]

i just thought of another question.....

when you guys refer to "blasting", are you talking about sand blasting or some other media. i have access to many different grades of silica sand from #12 thru #120. can i use this on aluminum and steel? i also have a black slag in 16/30 and 30/60 grades. will this stuff work or do i need to use something else?

my initial plan for cleaning parts is as follows:
1) degrease parts with cleaner
2) sand blast
3) clean with soap/water
4) wipe down with acetone

are all of these steps necessary or am even missing something?

 

[Ozz]

Caswell, Eastwood, or PowderBuyThePound all sell supplies like that. Best pricing varies on what you're buying, usually I find that one will have a better price on a couple things but not everything. Eastwood usually sends out 10-20% email coupons and free shipping coupons along w/their orders, so that helps.

Sand will work but the recommended method is an aluminum abrasive, glass bead, or even a coal slag like Black Beauty. Sand can be dangerous and cause lung/breathing disease. Your plan looks very good; you could get away with just blasting and coating if you wanted to. You could use denatured alcohol instead of acetone, too.

 

[undercnstrction]

sounds good. i'll try using the black slag that i have and see how that works out.

i just called the local harbor freight and they have the gun and a couple of colors in stock so i'll pick that up tonight and maybe try my hand at getting something coated tomorrow. HF also has a set of silicone plugs. do you use those? I would assume they get pulled out of the piece prior to baking correct? do i need to be concerned about the powder "melting" into any thread holes?

DAMN i'm full of questions

 

[Ozz]

The plugs are made to survive the baking process. If you were to pull them out after coating but prior to baking, you'd likely knock some powder off the part. Don't worry, they can take it. Same goes for tape. I use them when necessary, but to be honest most brackets I do I just shoot 'em and that's it. I haven't had any problems with threadings.

 

[undercnstrction]

right on.

 

[undercnstrction]

picked up a HF gun and a few other PC supplies. i'm going to shoot a couple of wrenches today (hoefully) and see how it comes out. if i get them done, i'll shoot some pics and you all can be the judge on how well i did

 

[Ozz]

Good luck man, the hardest part is getting together all the equipment. Me, I built my shop in the garage. Had to buy a compressor large enough to handle constant media blasting, had to wire the damn thing and of course upgrade the entire electrical for the house, and I bought a giant oven to handle whatever I will ever need to. The rest, the actual coating stuff, is simple!

One more tip, it's not necessary but this is how I do it and never have problems or 2nd guessing. Bring the oven to 400* and then put your parts in. Once they've been in for 15 minutes they're ready to come out. You can check their temperature, which should at 370-390, to know when they're ready to come out. Reflective chrome/candy colors show a lower temp on an infrared gun, but you'll get to know what the parts should look like when they're fully cured. You can keep them in up to 20 minutes too; larger parts will more than likely need the 20 min. cure time. Keep an eye on your first few batches of parts and you'll be able to see when parts call for a few more minutes. You don't want and shouldn't need to go any longer than that, however.

After 5 minutes in the oven you'll be able to see the powder on the parts begin to break down and coalesce (flowout). At 10 minutes or so you should see complete flowout and small parts will probably look like they're finished. Just keep the timer going and check again at 15 minutes. If they all look good and are at the right temperature, you can either pull them out or shut the oven off/open the door and let them cool.

 

[undercnstrction]

you mentioned checking the temps of the pieces. do you use one of those laser pointer temp guns? looks like i need to go back to HF

 

[Ozz]

Yes I use one.

 

[undercnstrction]

i have the temp gun issue resolved.

the kit came with 3 different sized tips. the middle sized tip is the one that was installed on the gun from the store. is that the one you recommend using? will it make much difference?

 

[Ozz]

The larger one you use, the larger cloud of powder you'll shoot. You'll find less waste by using a smaller one on smaller parts, but you can get away with either of them just fine.

 

[undercnstrction]

great thanx!

i've got to pieces prepped and ready to shoot. i will have them done today

drum roll please.............................................................................

 

[undercnstrction]

i'm a tad confused on cure times. do i need to keep them in the oven for the initial cook for roughly 15 minutes, than an additional 15 minutes to cure? or should i shut the oven off after the first 15 and just let them cool slowly? i've got one part hanging with color in the gun.....IT'S GO TIME

 

[Ozz]

Just put them in a 400* oven for 15-20 minutes, that's all you need. Very quick. MOST powders cure at that temp/time, if not it'll be mentioned on their spec sheet when you buy it.

To cool them off either pull them out of the oven and hang them somewhere, or just shut the oven off and open the door. Either way, same deal.