Any experiance using 3-d printers for parts?

[maple_leaf_eh]

Originally Posted by David Herbert

It is also possible to 3D print a pattern (from which to cast a metal part) in wax. This is then used in a lost wax casting process where a ceramic coating is used to cover the wax which is then melted out and the metal poured in. No 'draw' or loose cores required and almost any shape is possible with hardly any more effort. 3D printing in wax is about the lowest tech form of 3D printing as temperatures and pressures are obviously much lower than in PVC and in a different world to 3D printing in any metal.

David

I would echo this concept. My understanding of hobby and low-end 3D printers is the limitation is the medium. What I've seen lay down some heat based plastic compound. I have some hunter safety education dummy rounds for example, but they are no comparison to John's example of aerospace parts.

However, if you had a laser scanned file of the original piece, it could be laid down in casting wax. With your complex shape literally in-hand, you could make a metal casting.

[45jim]

jdmcm you are missing my point (unless I missed the point of Jim's request, but I don't think I did) you cannot REPLICATE an original cast part using a 3D printer. If you are trying to replicate the fit and finish of the original cast part so it appears totally original you can't just print one off, the finish and the mechanical properties will be different from the original. Not to mention no one is printing grey iron, bronze or brass (why would they want to?). If you want to print in wax and do a "lost wax" process then you will get good results, printing saves you several labour and talent intensive stages.

Given that this forum is for based on the restoration (ore resurrection) of old military vehicles, I believe that is the point of the question.

This has nothing to do with the wonderful things made with 3D printers today (and the many things you cannot make with them) this has to do with the replication of antique parts that look and perform the same as the original part.

Can you print Ti hex tiles, 20mm across and 6mm high, with similar properties to Norsk? Could you print a sheet of them 250x300mm? If so I have a proposition for you.

[Jim Burrill]

Maybe I should say what I am trying to make....

The Humber Armoured Car uses two, two-peice cast pot metal triggers - one for the BESA remote fire and the other for the remote 37mm cannon to be fired.

The triggers hang off of some steel bar stock mounted to the side of the 37mm receiver, and were used by the Driver to grab onto to pull himself up from the side crew door. Obviously, they had a hight rate of breakage!

My HAC came without the mount or the triggers.

Clive Hughes had a project to cast repros up as a "back burner, get around to it someday" project.

A friend imported a DAC that had both triggers and let us borrow one to use for a sample.

We let the project slow-track as we had a unplanned majorengine rebuild take prescidence.

Original plan was to take the two simple halves of the trigger itself and cast a few replicas ourselves. Aside fromt he cast handles, the inside has a folded metal bit to be what your finger pulls on, and a couple of springs and alignment pins.

Technology seems to have jumped past our plan to make a mold and hand pour a couple.

It looks like a laser scan, a computer to adjust for size shrinkage, and a 3-d printer that can use something that qualifies as 'Pot metal ( or stronger) and try to order 4 of them.

If the metal looks like silver-ish pot metal, and we can smooth out the "layers" by sanding, we would call that a win. If we need to paint it to get it to look appropriate and be as strong or stronger than the original, still a win.

We also would like to have a gunsight mount scanned int he UK and the file sent to us int he States to be printed. (There are several Humber Mk4 owners that are also missing this part, so we could split the costs by 4 or 5.

OK, now who can I contact to a) gets scans made, and B) get a couple of prints made?