Pullman-Standard Mini-Hy Cube boxcar in 1:29

[Hydrostat]

Burl, very interesting approach. Did you ever try to use 0.1mm brass or copper sheet, clamped tight at the later 'welding area' with some aluminum blocks and then heat it with a torch?

Cheers,
Volker

[Burl]

Volker: not for this.  Don't know how I would mold something during clamping.  Material thickness also has a big effect on how it ripples.  Stuff that behaves "to scale" is usually very easily damaged when handling.

I have used thin copper sheet for stamping roof panels, and waffle sides. 

[finescalerr]

This is sophisticated stuff. Of course Volker already is familiar enough with it to offer suggestions. (And here I am, messing around with primitive paper structures ....) -- Russ

[Hydrostat]

Burl,

to start of with, no, I didn't try it myself. Please excuse that sloppy artwork, but it shows the idea behind it. Annealing the sheet between the angle sections should make it warping while the clamped areas keep cool and stable. I thought of using the brass sheets for building the car (or then making a mold of the whole sidewall ...)



So far for theory. For the Rollwagen project (Codename Rosebud  ) I had to solder a rather large sheet of 0.5mm brass sheet to an solid 7 mm brass core and people told me, that it doesn't work without having the sheet warp. It works with some clamping during soldering http://www.finescalerr.com/smf/index.php?topic=2355.msg51524#msg51524. Maybe the principle works the same if you want a not clamped area to warp.

Cheers,
Volker

[Burl]

Sounds like the fundamental theorem of scratch building: that which should stay flat, will warp; and that which should warp will, will remain flat.

[Hydrostat]

If it's that easy just backflip the part  .