Do I need to create a sealed volume to place it in because it will ooze out? How secure do I need to make it to place it in a model?
Mine needed a corral to stay put. I sealed the top of my weight container with some ca to make sure if the thing ever inadvertantly was laid sideways it would stay put. It does slowly ooze, at least the stuff I got does. Mike
I got a pack of tungsten putty from the local Hobby Lobby, and it specifically says "non-hardening", so I assume the same. I'm building a 3D printed Jordan Spreader in N scale, and it's as bare bones a kit as they get. Basically a craftsman kit. I thought about adding tungsten putty between the lower sill rails, but how to secure it will be a challenge. Might just add a blob under the cab and seal it up 100%, and call it good. There's a big box above the rear truck (literally, according to the Jordan drawing, a ballast weight box) that I have a white metal casting that will suit there fine. It might still be underweight, but it's gonna have to be good enough.
I would get some tungsten powder from a golf pro shop and seal it in place with CA. It would probably end up with the same density overall and be a lot less messy. However, they charge a lot at the golf shop and you already have the putty so go with that sealed in with the CA. The tungsten weights they sell at the Pine Wood Derby web sites are probably too big to fit in a center sill but those are my go-to heavy metal weights these days. They can be ground down with a diamond coated wheel, but that takes time.
I used the putty on my early 3D printed gondolas. It stayed in place, though I did paint the putty once it was down so it would match the color of the car. The paint might have helped keep it fixed. I never saw any movement or oozing, but I suppose that depends on how humid things are where you live and inside your house.
I used it to add weight to my Shorty. It eventually escaped and ran down into the works. It was easy enough to clean out, but would rather it hadn't done that. I was able to contain it with tape.
I used them in my butter dish Milk cars they sit perfect in the center of the flat car then place the top on and they work perfect! still haven't decaled yet!
Just here to say lead is more dense than tungsten putty or powdered tungsten. Pure tungsten without any other alloy in it is heavier, but very hard to cut. I sometimes use 1/16" tungsten welding rods.
Very hard to cut, but if you score around them with a cut off wheel they will snap off. https://photos.app.goo.gl/9egB8rdosuWXfVHF8
