Pennsylvania A3 Switcher (Kozo)

[Kim]

Got some time in the shop today after the holiday festivities.  I started by doing a pretty good cleaning – putting all the tools back in their place, sweeping up the swarf and vacuuming things up pretty good.  It looks nice now!

I also spent some time unpacking the new addition that the Birthday Fairy recently brought me:  a new Eastwood powder coating gun and oven 

And since I had some time, I couldn’t just let it sit there thinking it was unloved, I had to give it a try.

So, I dug through my scrap bucket and came up with an interesting piece from some past project and decided to try that out.  It was an aluminum hunk from the 5-cylinder rotary engine I did a few years back that was rejected for some reason I don’t remember.

I cleaned the part really good then hung it up to powder coat.

I made a powder coating booth using the box the oven came. I only got black and red powder, so I went with red. You can sort-of see the grounding clip at the top of the picture. This is after coating BTW:


Then I moved it to my preheated powder coating oven (cleverly labeled as you can see) and waited for the powder to go liquid.
 

Here’s a close-up of the part baking.


And here’s the part after it cooled down.


Interestingly, I was supposed to wait for the oven to heat up to 450F before I put the part in, and I kept checking it with an infrared thermometer.   It wouldn't go up past 250.  I was getting frustrated.   I finally tried opening the door and it was WAY hotter!  I was checking the temperature of the OUTSIDE of the door (go figure - it doesn't read temp through the glass door...  of course! ).  Anyway, I put the part in, it seemed to go off in about 10 or so, then I set it to 400F and let it soak for about 20 min.  I took the part out and let it cool for a bit and that was all there was too it. Not that complex of a process really!

I’m just as tickled as you can imagine!

Tomorrow I’m going to strip the paint off the trucks and start coating the frame and trucks!

Kim

[cnr6400]

The first part looks great Kim! Nice result! 

Something tells me that the special powder coating oven could also be used to heat and discolour bread or different sorts of pies at breaks or lunch time.... who knew? 

[Ye-Ole Steam Dude]

Hello Kim,

That part looks really good, appears to have a nice heavy coating.

This is good to know, now if Bill is too busy to do any powder coating for me, 

Have a great day,
Thomas

[b.lindsey]

Great result Kim and it really isn't much if any harder that doing a good job with regular paint. Maybe not as many color choices but the Eastwood powders seem to cover most of the bases pretty well.  Happy belated birthday too!! Now looking forward to seeing the trucks once they are done !!

Bill

[Dave Otto]

That look very nice Kim!

The usual method for prep is to sandblast (at least that is what the guy that I use does), do you have any idea how well the powder bonds to the base metal if it is only cleaned and not blasted? 

Dave

[Kim]

Thanks all for the kind replies!

Dave,
I don't know how well the powder bonds this way. I'll play around with it a little more today and see if can give some metric on how well it bonds.  Just holding it in my hands now and scratching on it with my fingernails - it has a LOT better bond than any spray paint, that's for sure.  It feels quite secure.  Don't know how it will hold up when I start rubbing metal against it, but it can't be worse than that the spray paint I've been using.

The instructions they provide are to clean well make sure there's no moisture left on it and NO FINGERPRINTS - no touching the metal after the final washing. They do recommend a solvent based cleaner that evaporates quickly to help ensure the "no moisture" part.  I picked up their painting prep cleaner and used that. They claim its better than lacquer thinner, but I don't generally use lacquer thinner anyway.  I generally use acetone. Don't know if that's any better or worse, it's just what I use.

I'll have to give you a better reading in a few days on this

Any comments Bill? You have more experience with it than I do

Kim

[b.lindsey]

Not much more experience than you at this point, but I also followed the Eastwood instructions as you did and used their cleaner/prep as well. Like you say, the bond has so far been great and MUCH better than conventional paint. I suspect bead blasting would help even more but not required as long as you are down to bare metal for the powder coat.

Bill

[crueby]

Is it possible to mask off a design on the powder coat, and apply another color on top? Though that would require tape that would take the baking... 

[b.lindsey]

Chris, you can do overcoats, and in fact some of the translucent powders require a bast coat. Hi temp tape is available in both fiberglass and some sort of plastic.

Bill

[crueby]

Neat stuff.... Need to put one of those setups on my Christmas list...   

[Kim]

Yes!  You certainly need one of these, Chris!   Quite fun!

I'll post today's update soon (tomorrow sometime probably).  Unfortunately, today's session was slightly less successful - I don't think I got the powder quite thick enough this time, so it's going back to the paint shop for another coat.

But still, the process worked well, it was just inexperience on the part of the guy running the paint booth.  Hopefully he'll get better or I'll have to fire him

As for two colors of powder coat paint - I'm sure you can do this but after playing with the tape some today, it does mask the powder and withstand the heat - I can verify that.  But I don't think you get the same crisp line you would expect with sprayed paint.  It just seems to creep around corners and under the edge of the tape a little bit more than has been my experience with spray paint.

Kim

[b.lindsey]

Kim, were you using the fiberglass tape or the blue plastic hi-temp one? I ordered some of the blue but so far have only tried the fiberglass. I am hoping the blue may provide crisper lines at least on smooth surfaces. But I agree, the electrostatic charge will definitely pull powder into even small spaces if not masked perfectly.

Bill

[kvom]

Masking is probably the hardest part of powder coating.   

I bought a set of varying widths of tape for this purpose.  You can get a fine  edge if done properly.  I also got the set of plugs for varying size holes, although for threaded holes a screw works best. 

The Eastwood gun has two settings, with the #2 setting recommended for spraying tight corners and small spaces.

[crueby]

Which version gun kit did you guys get from Eastwood?

[b.lindsey]

Chris, I got the dual voltage one just to have the added capability.

Bill