stayboltI'd like to airbrush the gear, since that would result in the best coverage and allow the most accurate coloring and weathering.
Paul3When painting brass steam, the first thing to do is take it apart.
My presumption was that the OP was simply applying weathering.
Yes, if I am doing a full paint job of a brass locomotive I disassemble it and give everything a good cleaning, including removal of oils from the running gear.
doctorwayneI do the prep work similar to what Paul outlined, but purposely do not lubricate anything...the last thing I want on an item to be painted is oil.
See above.
Good Luck, Ed
Thanks to all for ideas....I'll give 'em a try!
Hi there. A few older steam locos have odd-colored gears, like the old Mantuas that had white gears. If they don't get covered by the airbrush, I will use a fine paintbrush and paint them dark black, along with the motor and any other component that is visible from the outside. I try to do this while re-working the drive line, but I often forget and do it later in the process.
Simon
I do the prep work similar to what Paul outlined, but purposely do not lubricate anything...the last thing I want on an item to be painted is oil.
Depending on the model, the procedure varies: brass locomotives with unpainted frames may be further disassembled, sometimes removing the drivers, along with the cylinder casting, and valve gear hanger, with siderods and valve gear intact, from the frame. The frame can then be airbrushed, or brush-painted, separately. After re-assembly, I generally brush-paint the driver spokes - it's sometimes difficult to get complete coverage of them, particularly at the wheel hub and where they meet the wheel rim, using an airbrush, without getting too much paint on the siderods and valve gear.The assembled chassis then goes to the spray booth. I have an old Bowser turntable bridge, on which the painting is done. If the motor and gears are in-place, I apply jumper wires from an old power pack to the motor, then, while restraining the loco from moving, turn on the power and airbrush as the drivers revolve. This could also be done with the loco's frame supported, front and rear, on blocks, or even upside down, likewise supported.When the paint has dried to the touch, I put the loco on blocks and run it for several minutes - this removes the uncured paint from all those areas that will need to be lubed after the paint has cured. After a suitable wait for that to happen (depends on the brand of paint you're using), all necessary lube work is done, which should leave no unpainted areas showing.With the loco upside down and powered, the driver treads are cleaned with lacquer thinner. I dip a suitably-sized brush into the thinner, touching it to the treads as the drivers turn, periodically wiping the brush clean on a rag. The lacquer thinner will work on pretty-well any type of paint while it's still uncured.Weathering a steam loco with an airbrush is done in pretty-much the same manner, with the loco fully assembled, powered and moving, while applying the paint. This ensures that the lead- and trailing truck wheels, and those on the tender get complete coverage. It's also a good practice when weathering rolling stock.
Wayne
When painting brass steam, the first thing to do is take it apart. I take off the boiler and remove the motor and gear tower from the chassis (plus remove pilot and trailing wheels if any). After washing in soap & water (and rinsing) and letting it dry (using a hair dryer helps), I then heavily oil all moving joints in the valve gear (don't forget the crosshead guides & piston rods), plus bearings, etc. After that, I heavily grease the main driver gear and put a light coat of oil on the treads of all wheels.
These days I use Tamiya spray can gray primer. It's good stuff and leaves a smooth hard coat. I spray the model with the primer and roll the wheels with my thumb or along the bottom of my spray booth and let it dry overnight (at least) under a spot light. It'll be warm without being too hot.
Then comes the paint. Spray it all (again, using my thumb or the base of my spray booth to roll the drivers) and allow it to dry under the light, too.
After all that, just scrape the paint off the wheel treads and other areas that got oiled/greased, decal, DCC, and reassemble. The oil and grease causes the paint to slide off rather easily. It's worth, but it beats taking all the valve gear off and masking everything.
I don't bother. The drivers usually come from the factory darkened somehow to a perfectly good look. The rods and valve gear come as bright metal which is prototypical. I take the boiler assembly off the frame and clean and paint it separately to avoid getting paint into the works or the need to mask the works off.
David Starr www.newsnorthwoods.blogspot.com
I made a length of track (HO for me) and anchored a Kadee coupler at one end. The track is on a piece of wood (door stop) that's about 5/16 thick and maybe 1-1/8 wide and this is mounted on a couple of wood blocks maybe 2-3" high. This allows me to paint up and under the running boards and air reservoirs.
I ran a length of 2 conductor wire from my DCC buss into the paint room and plug in the length of track. I keep the drivers turning at a slow pace while I airbrush the running gear.
I put a little lube on the rail and allow the drivers to slip. The paint goes on so thin that there's no problem with it getting into gears or bearings.
After everything is dry I can then clean off the tire tread with thinner.
Hope that helps, Ed
I'd like to airbrush the gear, since that would result in the best coverage and allow the most accurate coloring and weathering. Of course that means paint goes everywhere, including bearings, tires and motor parts inside the frame between the two sets of gear. Guess I could remove the gear, but I think I read an account of somebody spraying the gear while the engine was in motion; guess one benefit of that is preventing the rods from hiding parts of the drivers. To do that in a paint booth would mean suspending the engine (and tender... for electrical pickup in my case) from hangers and somehow jerry-rigging electric power.
Anybody found a way to do this with satisfactory results?