Shay - Painting
Nelson Riedel Nelson@NelsonsLocomotive.com
Initial:2/13/04 Last Revised: 09/20/2004
It's been over a year since the Shay was started.
It's been under steam on the test stand so it's had hot water and hot
oil scattered over the surface. Some pieces now have surface rust
while other parts have enough oil on them to keep away rust for a
hundred years. It's too cold to run it so I decided to
start the painting. The tender is essentially finished so it
could be completely painted. The locomotive is also essentially
complete except for the smoke box rivets, boiler jacket and domes. I
decided to paint the tender first and then do the trucks and the main
frame. If the weather is still bad at that point I'll probably try
to finish the boiler and get it installed permanently. The
various pieces of plumbing and pipes will be next and the cab and engine
last since they can be removed without disassembling the rest of the
The initial plan was to powder coat (PC) the smaller parts such
as trucks and engine and spray the larger pieces with automotive type
epoxy paint. However, after PCing most of the tender parts and
The mess of spraying
The cost of paint (~$200 for a quart of primer and a
quart of color and hardeners and reducers for each)
The need to heat the garage
The mess of mixing the paint again and again to do a
small group of parts
The spouse's complaints about smell & mess.
I decided to PC the whole thing. The biggest problem with
PCing larger pieces is to get an oven large enough to accept pieces
such as the 49" long main frame. However, I think I can
overcome that problem so, current plan is to PC everything.
I had already PCed the tender truck, frame, floor and tank top before I
thought to take any pictures. However, I can describe painting
similar parts of the main locomotive so nothing is lost. The
main thing I want to pass on with these notes is the degree of disassembly
I used. Some disassembly is required to do an adequate job of rust
prevention. However, one would be at it for a year if
everything is disassembled. Also, some parts won't fit together if
completely painted because of the paint thickness. The disassembly
is applicable to both liquid and powder paint.
|Sill: I had just finished making all the sill parts so
decided to start this with the painting of those parts. The photo
shows sill parts hanging from an oven rack. The parts
were cooling after the powder coating was heated for curing.
Sorry I didn't put something light colored behind the parts so
they showed up better.
|This photo shows the finished sill. The wood was painted
with RUST-OLEUM Satin black that had been diluted to about half strength
with thinner so that the paint would soak in but not completely
obscure the wood grain. Two coats were
used. I haven't decided whether to paint the
stainless steel screw heads. If I do, I'll use a small brush and RUST-OLEUM
Gloss Black. This paint can also be used to repair any
minor defect with the powder coating. That's the fuel tank
in the background.
The screws through the sill are 1.5" long hex head
stainless steel 4-40. I normally purchase hex head
screws from McMaster Carr. However, they don't carry 4-40
hex head screws 1.5" long. I purchased the longer
screws as well as some #0 & #2 hex head screws from Microfasteners.
They gave quick delivery at a good price.
|Tender Tank: This shows the tank after the power had been
sprayed on the tank but before the curing. Before spraying, the tank was taken outside and
blasted to remove all oil and surface rust. Next, it was
heated in the oven to drive out all liquids that had accumulated in
the seams and around the rivets. After the heating there
were faint oil stains around a number of rivets. If the oil had
come out during the curing process, the paint gloss would be ruined
in those areas. After the heating the tank was blasted
again. The powder was then applied in the vented paint
booth. If it was warmer I'd have done it
|The support shown above positions the tank in the center of the
oven but sticking out about 6 inches. The photo at right shows the oven
extension made from fiberglass duct panels held together with duct
tape. I had previously dubbed this device the pregnant
oven for obvious reasons.
|This photo shows the cured tank.
Normally I heat the oven to 450 degrees and then
after the powder flows back the temperature off to
about 400 degrees for 5 minutes for small objects and 10 or 15
minutes for heavy objects. I used 355 degree soft
solder on the tank so had to keep the temperature below about 325
degrees. I did some tests using small pieces soldered together
and also watched the oven temperature. I found that a
setting of 275 degrees had transients up to about 325
degrees. A setting of 300 degrees went above the 350 degrees
and the test pieces fell apart. I heated the tank at
setting of 275 for
about 20 minutes after first cycle of the thermostat.
Next time I'll use higher temperature solder.
|The next step was to paint the inside of the tank.
(Kenneth suggested that even the galvanized tank would eventually
rust. I had already seem some surface rust where I had
scraped off the galvanize.) I used KWIK-SET 3 - 3 HOUR SUB
SEA/MARINE EPOXY (McMaster-Carr). It turned out to be the
consistency of bread dough. I thinned it a little and
applied it with a brush. I did the bottom and
sides first and the next day did the underside of the top and
touched up the sides and bottom, The stuff is pretty thick
--- like a coat of stucco. The paint has embedded Kevlar
fibers so it should be able to handle really hard water rattling
around in the tank.
|The hand pump, overflow pipe and baffle were reinstalled
and then the cork strips were cemented to the top using Permatex
No2. That's the black baffle across the middle
of the tank.
|The tender is finished except for sanders on the rear of the
tank, a light and a cushion or seat of sorts.
The tender is now in the corner under the bench to make more room to work on the locomotive.
On to the locomotive .........