I’m attempting to vaccuform empty 115mm shell casings for a T62 diorama to allow for shrapnel damage as shown below
what I’m currently getting looks more like a tree stump than anything else.
My initial thought was the puckering down the sides is pretty much unavoidable with the height and diameter of the part (about 3mm in diameter) but am hoping to get some input. I’m using a Mattel machine with .010” sheet thickness.
Perhaps orient the shell horizontally and raised off the base - this will mean it will have to be cut away but that surface can be be installed down on the diorama.
I will give that a try, thanks Richard !
The alternative would be to draw the warm plastic down into a hole instead of drawing it down over a peg but the depth/diameter ratio would likely cause problems
In my opinion, brass shell casings would be a better option. 105mm casings are close enough for 1/35, to me anyways.
To my eyes there are significant differences, with the 115mm shell the necked diameter extends almost half way down the length.
Something to consider, thanks !
Found these too. They are resin, so you could drill them out as much as you need. Making resin copies of them would give you more rounds to work with as well. Vacuforming just doesn’t do well with small, cylindrical objects.
Drilling them out deeper isn’t really the issue, I can drill brass as easily as resin. It’s having a consistent wall thickness down the whole length of the casing which is what I’m attempting to get with vaccuforming. Thanks for the input, though.
Perhaps telescoping brass tubing / solder and paint ?
The 105’s don’t look right. That would be like using .22 casings to represent a105 casing. Someone actually recommended that once.
Wow. Busy last fifteen minutes while I was drawing.
You mean like this?
Access to small lathe?
Just what I suspected.
Exactly
I have not used this particular Mattel toy in a while. (Al though I keep the others close by) 
if you’re intenton doing vacuforming them, all is not lost. You can split your master lengthwise and make them in halves. Obviously a little sanding would be involved, but it would work.
Yes, that’s what I turned the pattern on.
That’s what I’m using. Wondering if I might be better off with something other than the hand pumped vacuum although it does seem to be surprisingly strong , at least for a short period of time.
Ah, like Sheps’ “Isherman” gun barrel.
It’ll be more than strong strong enough if you re-orient your pattern.
Is your lathe programmable? If you can reproduce the casings I’d just use a 3 mm end mill (as opposed to a drill bit) to hollow them out. You can do final finishing to 3.2 mm with emory cloth.
