Pennsylvania A3 Switcher (Kozo)

[Kim]

Before you can powder coat anything, you have to figure out how you’re going to hold it while spraying on the coating and in the oven.  And while spraying, you have to have a way to ground the parts so that the charged powder coming out of the gun will be attracted to, and stick on, the part.  I’ve done this enough that I’ve got ways to deal with most of the parts, but these long sand pipes took some thinking.  They were too long to dangle down from the rack like I do with most parts.  And there was no way to support them from both ends without damaging the paint at one end.  So, this is what I came up with.  I used a slug of aluminum that I had in my junk bin.  It actually worked quite well. And it got the top part of the hold down screws painted too!  I was pretty happy with how it worked out.


When I first started powder coating I would hang each part to be painted in my powder coating booth (i.e. cardboard box) and spray it, then transfer the part to the rack for baking.  This caused me a lot of problems because I'd bump the part on something when moving it, or bump it into another part while hanging it on the rack.  This, of course, would cause powder to fall off the part and make little holes in the paint coverage.  Never fun to deal with.

But over the years I've come up with a better method.  I suspend the parts from the rack, just like they will be in the oven, and apply the powder to the parts in situ.   This works MUCH better and I have far fewer issues than I did before.  To facilitate this method, I made some supports that suspend the rack above the table and in front of my powder coating booth (though in this picture, I put one of my whitish backgrounds in front it blocking the view of the box - er my powder coating booth.)  I also cover the rack with aluminum foil. The foil has two benefits – one is that it keeps the oven rack from being covered in paint.  The other is that it is conductive so it helps connect all the parts to ground.  I clip the ground to the top side of one of the wires above the rack and the rack and foil ground everything else.  This does mean that the underside of the foil gets painted, but that’s better than painting the rack. And when it gets too much paint on it, I just replace the foil.  In this pic, I’ve just applied the powder to all of the electrical conduits.


Then I carefully move the whole rack over to the oven for baking.


After a couple of days of this process, here are all the powder coated parts.  The parts I wanted to leave unpainted were all coated with a clear coat to help keep them from rusting or tarnishing.


And here’s the number plate from the front of the engine.  I did two colors of paint on this one – the back and sides are painted black, but the background around the number was painted red.  I did the black first, then baked the part.  After it cooled, I changed all my masking and then painted the red part, and baked it a second time.  This is the first time I’ve ever put two different colors of powder coat on one part.  I think it came out pretty well!  I will be adding a clear coat to this part too, to keep the brass nice and shiny.


Well, that’s it for the painting (I hope!)  Next, I’ll be reassembling everything, plus figuring out how to wire up the headlamps for the first time.  Not that it will be hard, just a lot of new detailed work.

So stay tuned!
Kim

[cnr6400]

  Looking great Kim! really like the two colour number plate.

[crueby]

Thats a LOT of parts to coat! Looking So different. 


 




That ali chunk with the rods looks like a modern art piece, Seaweed At Sunset...

[Krypto]

Those parts look great!  That loco is really going to be an eye-catcher when it's all assembled again.

I bought a used powder coat system from a fellow at work and finally had time to give it a try out a few weeks ago so your hints are perfectly timed. Like you said, getting the stuff from the booth into the oven is the hardest part and my small toaster oven doesn't make it any easier.  I like your rack idea and after looking at some pics of my oven I believe I can add some supports to hold the rack at the top of the oven space.

There's a few 3D printed hop-ups for the Eastwood gun on Printables.  I found the custom funnel for the plastic bottles to be particularly nice.

The seller had a separate earth ground installed for the system and the instruction book mentions having a good ground many times.  Luckily for me, my shop had an old land line telephone installed (disconnected awhile ago) and they handily put a ground for the phone right by the outdoor work table I use for powder coating so I'm going to tap into that.

[Kim]

Thanks Jeff, Chris, and Krypto! 

The seller had a separate earth ground installed for the system and the instruction book mentions having a good ground many times.  Luckily for me, my shop had an old land line telephone installed (disconnected awhile ago) and they handily put a ground for the phone right by the outdoor work table I use for powder coating so I'm going to tap into that.

I don't actually use an earth ground.  The manual doesn't say anything about that.  But the electric box that hooks to the gun has a ground lead with an alligator clip.  I connect that alligator clip to the parts to ground them.   It works quite well.  Conversely, if you forget to hook up the clip, it doesn't work very well at all!  Ask me how I know! 

I really like the process of powder coating. I enjoy it SO much more than regular painting.  I get much more consistent results and find it far less frustrating.  Plus, it is a much more durable finish than standard spray paints.  I think you'll really enjoy it!

Kim

[Krypto]

I'm talking about this book:

https://www.eastwood.com/eastwood-beginner-s-powder-coating-handbook.html

Blondihack's recommended it in her video about powder coating and it is a good one.

If you use your dot com machine and search for powder coating and grounding you'll find tons of references about this.  It's a big deal.

https://reliantfinishingsystems.com/proper-grounding-techniques-powder-coating/

[Kim]

Interesting.  I've never had any issues with using the ground supplied from the unit.  Maybe that's because I've only ever coated smallish parts?  The largest would probably have been the tender tank.  But that coated quite well with just the supplied ground.  I'm sure that ground is the same as the house ground since the electrical unit has a 3-pronged plug. I'm sure it uses the house ground. I should do a continuity check to see.  Regardless, a good ground is important.  Maybe I'd get even better results if I used a bigger ground lead?  May have to play with that next time I do any more powder coating.  But I can say I'm quite pleased with the results I've been getting.  YMMV.

For me, one of the biggest issue was getting the proper airflow.  If it is too low, you don't get the powder you need.  If it's too high, it can blow the powder off the part you're trying to coat.

And for parts with a lot of detail and/or recessed areas, I have found the diffuser on the end of the spray gun to be invaluable.  In fact, I almost never go without it these days.

And be sure to clean off the electrode tip on the gun from time to time.  It gets covered in powder and won't provide the electrical charge to the powder as it blows by.  If I find the powder not sticking well, this is now the first thing that I check.

Kim

[RReid]

That's quite a pile of pretty parts, Kim! I really like how you did the number plate, looks perfect. Eagerly awaiting the final, fully assembled result!

[Kim]

Thanks, Ron! 
Kim

[Kim]

The wiring went well for the most part.  I got some little connectors to use at the ends of the runs to allow for assembly & disassembly.  Here I’d just soldered the connector to the LEDs for the headlamps.  The LEDs were then pushed into their respective homes in the reflector and the backs were put on the lamps.


I tried using the high-temp wire that I’d purchased, but I don’t think I got the right stuff. It was a smaller gauge than the wire-wrap wire and was stranded. It was SO flexible that I couldn’t fish it through the conduit.  It wouldn’t stay twisted with anything.  I could have soldered it to the fish wire, but I was just so worried about how small the wire was – I was afraid it would break as I was working with it.  So I went back to just using the 30GA wire that I had. It worked just fine.  And if the wire ever melts, I guess I’ll deal with it then.  But I think the conduit and the boiler jacket will keep the wire well within tolerance, temperature-wise.  Besides the fact that I likely won’t be firing it   


And finally, about halfway through the assembly, I was able to solder up the switch with the connector leads.  In the junction box/heat shield, I have 3 connectors hooked up to the switch; one goes to the battery and two connect to the lights.


After a LOT more assembling… and disassembling to put in a piece that I forgot needed to be done earlier, etc. I finally have a completed switcher!  I took a bunch of beauty shots, some with the headlights on, and some with them off.  I’m really quite pleased with how it came out!












You’ll note that the pressure gauge is conspicuously absent.  I’ll be making that next.   It will connect to the front of the steam manifold and be positioned on the left top side of the boiler.






And there you have it!  A nearly complete A3 Switcher.  All it’s missing is a pressure gauge!

Kim

[AdeV]

Wow, that is a thing of beauty. Seriously well done!

You've actually got 2 more parts to make... the pressure gauge - and a short piece of track for it to sit on!

[crueby]

Simply exquisite!   

Amazing how different it looks with the powder coat/paintwork. I may contact you later to dial down your grin, I can see the glow in the distance!!


Am looking forward to seeing how the pressure guage build goes, have seen that chapter in his books, but never attempted one. So, some more watching to do!   

[Dave Otto]

That sure is something to be proud of Kim!
All that hard work has turned into a beautiful model!

Dave

[cnr6400]

  It looks just fantastic Kim! the powder coat looks amazing. Well done! 

[Krypto]

It looks incredible! You should feel very proud as I'll bet that quite a few of these engines are started but few are finished as it's so much work and more than a few parts are quite tricky (boiler) to make.

Thanks for taking us along on the journey!