Author Topic: Pennsylvania A3 Switcher (Kozo)  (Read 25112 times)

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #405 on: July 29, 2019, 02:19:18 AM »
That's an interesting thought, Dave.  There's a lot to this powder coating thing that I've never considered before!  (not surprising, since this is my first exposure to it :)).

Kim

Offline kvom

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #406 on: July 29, 2019, 03:53:38 AM »
I use a CO2 tank for powder vs. an air line.  It's very easy to get low pressure flow, and the same tank can be used for air brushing.  No water in the line is a plus.

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #407 on: July 29, 2019, 05:23:22 AM »
That's interesting - C02, eh? How expensive is it to keep that filled?  Do you find it lasts a long time or do you get it filled frequently?  That does seem like a clever idea!

Kim

Offline kvom

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #408 on: July 29, 2019, 12:29:11 PM »
20 pound tank costs about $18 to refill.  For purposes of powder coating models it would likely last for years.

I got it originally for inflating offroad tires.

Offline b.lindsey

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #409 on: July 29, 2019, 02:51:40 PM »
Kirk, did you have to buy the tank initially? I assume it need some sort of regulator as well similar to welding tanks. Interesting idea though for sure.

Bill

Offline b.lindsey

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #410 on: July 29, 2019, 02:58:08 PM »
Kim, those look great. Hindsight is 20/20 of course but a cradle made out of aluminum bored to accept the bare ends of the shafts with just enough exposed to turn them might have worked also. You could ground the cradle and even transport the powder coated shafts to the over while still in it. Maybe too much trouble for just the four shafts however. I am really enjoying your work on the powder coating though, need to get back to doing more of it here. I keep finding things I now want to redo in powder as over the years paint has chipped off, etc.

Bill

Offline kvom

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #411 on: July 30, 2019, 12:02:09 AM »
These are common in the offroading community, and one can buy complete setups.  The guy who sold me this one 15 years ago married a soda tank to a regulator and a hose.  I think I paid about $120 for the setup.

Offline Steamer5

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #412 on: July 30, 2019, 04:05:58 AM »
Hi Kim,
 Thatís coming on nicely! Loving the powder coat tutorials.
To help find leaks on air fittings in the future, if you donít already know, a little dishwashing liquid in some water......bubbles & youíve got a leak, makes life a whole lot easier!

Cheers Kerrin
Get excited and make something!

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #413 on: July 30, 2019, 05:50:33 AM »
Thanks for the additional info on the CO2 Kvom.

Hi Bill, yes, lots of ways to do this.  I just have to start thinking a little differently for the powder coating.

Hi Kerrin, Thanks for the tip on the leak finder!  Yeah, the way I finally found the leak was to submerge the whole thing in a bucket of water.  It worked!  Your way would have been a lot easier though :)

Kim

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #414 on: August 04, 2019, 05:43:31 PM »
Having resolved my shop infrastructure problem with the air system last week, THIS week, I was able to make real progress!  That, and Iíd already had most of the parts masked and prepped Ė which helped a LOT!

I coated and baked 5-6 ovenís worth of parts this week!  Hereís one batch, just before being removed after their 20-minute bake at 350o.


There were a few parts I decided to re-do a little.  The worst was the axle that slipped out of his tape.  Hereís the before shot.  This isnít exactly how it looked coming out of the oven.  This is after some sanding to clean up the flattened spot in the paint.  The upper axle is a good one, the lower one is the one that fell (hopefully you can tell :))


My first idea was just to reheat the part thinking that the paint would re-flow.  Well, that didnít work.  So I tried it again with a very fine dusting of powder.  It came out passable, especially for a part that will be underneath and not seen.  Again, the axle I was repairing is the lower one.


For later repair jobs, I removed more paint and sprayed more powder on them, and that worked better.  Iím sure the best thing would be to completely strip the paint off and start over.  But I didnít do that.  And they all look pretty good to me!

Hereís the full family shot before re-assembly.


Next job is moving on to the actual tank, starting with the floor. Iím excited to get to this next phase now!
Kim

Offline b.lindsey

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #415 on: August 04, 2019, 06:05:30 PM »
Those look fantastic Kim. I think you are now the MEM powder coating guru, and your great pics and descriptions will surely help others getting into this area  :NotWorthy:

Bill
« Last Edit: August 04, 2019, 09:13:04 PM by b.lindsey »

Offline Dave Otto

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #416 on: August 04, 2019, 06:46:09 PM »
Nice looking family shot Kim!
It appears that you have the powder coating process nailed down pretty well.

Dave

Offline mike mott

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #417 on: August 04, 2019, 06:55:39 PM »
Hi Kim, I am curious about the differences between the painted parts and now the same parts have been stripped and powder coated. Is the powder coating that much better than an enamel finish? It also appears to a more complicated process.

Mike   
If you can imagine it you can build it

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #418 on: August 05, 2019, 03:31:08 AM »
Thanks Bill and Dave,
I've certainly been learning a lot, and I'm WAY better than a few weeks ago.  But guru?  more like second level neophyte, I'd think  ;D
But thank you,
Kim

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #419 on: August 05, 2019, 03:47:18 AM »
Hi Kim, I am curious about the differences between the painted parts and now the same parts have been stripped and powder coated. Is the powder coating that much better than an enamel finish? It also appears to a more complicated process.

Mike

Hi Mike,
I'm not enough of a paint expert to make any kind of blanket statements about what's better or worse.  I'm sure there are great enamel paints - like stuff they use on cars that has to be baked on or something?  that's pretty good stuff.  But I can tell you the rattle can spray paint I've been using just doesn't hold up that well.  I've been using Rust-oleum, but I've used other stuff too (Krylon, etc.) and none of it adheres that well, with our without primer.  The powder coating really adheres well!  Like, when the screwdriver slips off the head of the screw and you ding the paint - that happened frequently when using the spray paint.  But with this stuff, it doesn't really phase it.  The paint adheres very well.

On my test piece I took an exacto knife and scratched around on it. While you could see the marks (if you pressed hard enough) it didn't scratch all the way through to the metal.  Yes, you can keep scratching and cutting and get to the metal.  but you have to work at it.  It has way better adhesion that anything I ever got from a rattle can.

As for ease of application - yeah, the powder coating has some steps to it, and does make a bit of a mess.  But really, so does spray painting. We're just used to it.  And the best part for me is that I don't have to wait x-hours and re-coat (often 3-4 times). And then wait 24-48 hours while the paint dries.  The powder coating goes quite fast.  Spraying the powder on doesn't take that long, and the whole curing process takes about 30-35 minutes.  You bake it at 450oF till the part gets up to temperature and the powder starts to flow (about 10 min I've found with most of these smaller parts, maybe 15 or 20 with the bigger thicker parts), then a 20 min bake at 350oF to finish curing the paint.  After that, you just let them cool, take the masking off, and they are good to go!

I'm getting better and NOT having to re-do parts.  Most of the problems tend to be as I'm moving them from the powder coating both onto the rack.  I have to be careful not to brush one of the other parts with the back of my hand, or the side of my thumb or something.  That will knock all the powder off in that one spot. But I've done a few touch-ups by applying a little powder and re-baking.  Again, not that different from touching up a spray job - other than it takes FAR less time for the pain to dry.

So, yeah, there's some process involved. But right now, at this point, I am finding it WAY better (and more fun) than standard paint.  But I do reserve the right to change my mind as time goes on :)

Thanks,
Kim