Re: Santa Fe tank car - Cocoa Beach clinic teaser


pullmanboss <tgmadden@...>
 

Jack Burgess wrote:

That is very impressive work and it is great to continually see new ways of
doing things. I'm sure that you will address this in your clinic but is the
final product durable enough to be used as a freight car on an operating
layout or is this intended as a master for a resin car?
Yes, it is intended as a resin casting master. Even so, I was concerned about several durability and suitability issues. There's the Archer rivets themselves. Even though they end up under paint, they're still on a base of decal film and not a part of, or bonded firmly to, the substrate. As a resin casting master that's not an issue, but on an operating layout, I suppose a derailment or rough handling bad enough to damage the paint might flake them off. They're certainly touchier than decals while you're applying and setting them, but that's a matter of technique and being aware of where your fingers are on the model. I can tell you that once set and dry, even without paint on them, they are more durable than I expected. They even survived scrubbing with a soft toothbrush, my technique for getting rid of fugitive flakes of unadhered decal film. (Figured the standard decal post-application wipe with distilled water might not be a good idea for the Archer's.)

The Avery label stock concerned me for three reasons. First, will it adhere properly, with no wrinkles or bubbles, and stay put? Second, it's not waterproof. Can I seal it so it takes water slide decals and setting solution without absorbing any liquid? Third, will it be affected by immersion in liquid silicone rubber for several hours?

For numbers 2 and 3, the results have been good. I'm still working the first one, proper and permanent adhesion. There's no evidence of poor adhesion between layers, only between the shell and the first layer. It seems to be a matter of surface preparation of the car core. On my first attempt I had all sorts of misalignment between layers, wrinkles, you name it. The car core was also shiny and smooth. Bad idea - there's no way for trapped air to get out from under the label stock as you roll it on if the substrate surface is ultra-smooth. The forgiving thing about the label stock is, if you screw up, you can just peel it all off and start over. (Goo-Gone takes off the adhesive residue.) I've done six applications so far, and applied rivets to three of them. The one in the photo was the second one with rivets and I must admit there was some delamination in the lower quadrants. Not much, but you can see it if the light is just right. My technique keeps getting better, though, and the latest one looks very promising. I rough-sanded the shell and used plenty of patience getting the Avery material in place. I let it sit for three days before sealing it with gloss acrylic, then two more days after that. Everything stayed dead-smooth, no evidence of any delamination. I applied all the rivets yesterday, and poured the first mold half last night. Just poured the second half before I started writing this post, and tomorrow (Wednesday) night we'll see if it's still good.

Tom Madden

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