Tom, Richard and Tony are essentially correct with their answers. I used the Tichy frame because it was the best available at the time and I would use it again, today. It lends itself easily to kitbashing and modifications.
I did not add the weld to the .005 wrapper, but I have no knowledge if this is correct. I remember being worried that if I scribed a weld line in the .005 styrene wrapper, it would be weakened and when glued to the body it would not curve smoothly, but rather leave a slight peak. Today, you can add an Archer weld line if need be.
The P2K Type 21 tank is approximately 29'9" and larger in diameter. My car is 32', but I don't remember how I arrived at that figure. The P2K tank does have die witness lines running horizontally, on both sides, the length of the tank, which I don't believe represent anything found on the prototype.

Mark Feddersen

--- In STMFC@..., "pullmanboss" <tcmadden@> wrote:

Dave Sieber wrote:

Tom, although I don't have the Oct 85 MM ready to hand, I seem to remember that the reason Mark Fedderson said not to remove the Athearn tank's top seam was so it could be used as a guide to accurately placing the new dome vertically on the top of the tank circumference, since the original mold seam could be seen through the clear plastic wrapper that he'd used.

He used the weld bead (his term) to align the two halves of the shortened tank body when bonding them, but is silent on using it for dome alignment. But is it really a weld bead, or just a witness mark where the two halves of the die meet? In any event, I will make a mold, but I'll leave the ridge, whatever it is, on the pattern. It'll be easy enough to remove from the castings for those who wish to do so.

Tom Madden