Casting buffers

Last year I bought a second hand LGB tramway locomotive. When I bought it one of the buffers was missing, the other one fell of almost directly. So I decided it had to have new buffers and a while back I made a RTV mold from the one remaining buffer (I thought I had some pictures of that but I can't find them at the moment). Yesterday I casted new buffers from tin (pewter?).

As you can see I was accompanied by a true silversmith!



The newly produced buffers at the right. The detail was pretty good actually.
I casted a few more so I have a little stock now. The ones that did not turn out fine get right back in the melting pot, as you can see! It is real fun you can use the tin more than once.



And after cleaning up this is how it looks like on the model.
It has a screw in it from the rear because the casted buffer is rather heavy and I did not trust to glue it.



We both had a great time experimenting with this.
We also (tried) casted a few brake levers, some H0 scale imitation axle bearings and a nameplate but those did not came out very good. I have to work on these molds a bit more (make some small air tunnels in it so the tin can flow better to all places) or perhaps make some new molds.
And the thing was that the RTV I used was already one year overdue and I had the feeling this influenced the quality of it.

Some new molds are planned using some LGB parts (levers, airhose). This way I can copy the parts for use on second hand LGB stock were parts are missing or even better; in scratchnbuild projects.

Excellent

...or start a business casting for other people!

It's great when the kids get involved and your son looks identical to you.

Excellent thread ! I've been tempted to try a bit of pewter casting, but I've usually given up at the mould making stage as I end up with bubbles in the RTV. Its good to see some nice results.

One day I'd like to try some sort of vacuum chamber to de-gass the RTV before its poured.

Nice to see an appropriate use of child labour - start him on a four hour day in the foundry and work up from there as demand increases....

You should try doing a whistle next. The plastic ones are way too fragile. I'd buy one.

Thanks guys!
Making molds was trail and error for me as well. I allowed myself to mess up my first can of RTV (500 ml) but the results this far are not that bad.
My first mistake was to make the second mold part directly on the first one without any solvent. I had to cut the parts out of a solid block of RTV.
I use a thin layer of white vaseline as solvent between the molds (cheaper than the solvent spray) and it works good. I also heard some people use silicon spray as solvent.

I did not had much bubbles in it. With a small brush I applied a thin layer of RTV on the parts itself so these are well covered with RTV and than gently poured over the rest of it. This seems to work fine. The RTV outer sides sets very fast but the inside takes about 12 to 24 hours at least to harden out.

This was the article I used as guide: Metaal gieten It's in Dutch but I guess the pictures are showing a lot on how to do it.
The blue stuff that the author used to stick in the parts for the first part of the mold is Kids Dough. I followed this method and this works very good. The baby powder helps to let the metal flow inside the mold.

EDIT:
Oh, and my son is already applying for a management position... Chief workshop or something.
Demands: lemonade and SpongeBob movies

Bill, if I ever succeed in making a whistle you get one for free

Here a link, its in French, but the picture are good enough to understand the process like the Dutch one.

http://www.pocher-protar-custom.com/moulage%20pot%20RR.htm

And the second link is a video in french :

http://video.google.fr/videoplay?docid=-2936038812441823931

Paulus wrote:

Bill, if I ever succeed in making a whistle you get one for free

Would delivery involve another visit to Eindhoven?

Seriuosly, if you do succeed in making whistles, I would happily pay for them.

KleineDicke wrote:

Paulus wrote:

Bill, if I ever succeed in making a whistle you get one for free

Would delivery involve another visit to Eindhoven?

Seriuosly, if you do succeed in making whistles, I would happily pay for them.

Yes, I forgot to mention you had to pick it up personally

But seriously, what sort of whistle you had in mind? The one that's on top of the Stainz?
I'm thinking to try to duplicate that one for my steamcar, but if you have other ideas, let me know!.