[modeleng] Re: Brass dome cover for Tinkerbell
- From: "Phill Smith" <steam@xxxxxxxxxxxxxx>
- To: <modeleng@xxxxxxxxxxxxx>
- Date: Wed, 9 Nov 2005 11:52:29 +0800
Peter,
As I see it, you have 3 options;
1/ Try to spin it out of one piece, yourself. This requires a very large
steel former if you want to do it properly. I have spun 6" diameter domes,
and they are a right pain in the backside unless you have a spinning lathe
(which is like a cross between a wood lathe and a metal lathe on
steroids........). It puts a lot of force on your tool post when you're
spinning deep stuff.
2/ Fabricate it out of sheet. This is quite easy, though you still need to
make a large former to spin the cap. The best method of joining them all
together is to have it TIG welded, as this will ensure that it is all the
same material, it will form the flare correctly, and there will be NO
tell-tale lines. Silver soldering is not a good idea, as when you try to
flare the base, the silver solder will not want to move. It also leaves
impossible to remove white lines, and rubbing back the excess silver solder
(without cutting away the surrounding brass) is very hard work.
3/ Have it spun professionally. There are still a few of spinners around,
and they don't charge the earth. You will have to still make the former to
fit their machines, or else you'll have to pay for one to be made. If you
have a good chat with them, they may well have a former already turned up
that only needs a slight modification to do the job.....
I would really recommend that you spin it out of no less than 1/8" sheet.
That is a long draw to do, and by the time you have finished, the metal will
probebly be only 1/16" thick at the flare. The hole for the safety is put in
as the last machine operation.
If you really want to spin it yourself, let me know and I'll scan some info
for you.
Cheers,
Phill.
MODEL ENGINEERING DISCUSSION LIST.
To UNSUBSCRIBE from this list, send a blank email to,
modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.
Other related posts:
