RE: [rp-ml] Watch Cases

Hi Lloyd,

Bernard is correct in saying you should design around the myriad of parts
available.

You may also consider a flat silver/gold watch back secured with 4/6
stainless steel screws. Naturally you would need to tap the threads which
should not pose too much of a problem. Stainless steel screws similar to
those used for spectacles will probably do the job (if you don't have access
to a mini tap).

Don't forget to make allowance for a rubber gasket in your design!

I too, would be interested in your progress.

Kind regards.

Anthony O'Brien
www.iwjdesigns.co.za <http://www.iwjdesigns.co.za/>
Johannesburg, South Africa

-----Original Message-----
From: owner-rp-ml@rapid.lpt.fi [mailto:owner-rp-ml@rapid.lpt.fi]On Behalf Of
Bernard Bryce
Sent: 10 April 2008 04:15 AM
To: Ricardo Amaral; rp-ml@rapid.lpt.fi
Subject: RE: [rp-ml] Watch Cases

Hi Lloyd,

I have a solidscape machine here, and about two years ago I had a go at
designing a silver watch for myself as a novelty..... drew it up in CAD,
printed it on the 0.0254 build on the solidscape machine, and then got it
cast... Unfortunately that's the easy bit! Finding most of the watch parts
was also no problem. There are loads of suppliers. There are even companies
who supply dials, ready printed with your design etc..

I think Ricardo is right, you will need to machine the Glass seat, and the
threads for a screw in back (if that's what you choose), and you will
probably have to drill/machine out the winder hole.

If you are just making one watch , and you don't have a lathe, it would be
possible to make up a hand tool to carefully 'ream out' the glass seat. I
was planning a similar approach to ream out the back to take a press in
back.

I didn't have too much trouble polishing up the outer case after it was
cast as it was built on a fine build on the solidscape machine, and
properly cast . I drilled the spring bar holes manually.

Believe it or not, the biggest problem I hit was finding stainless steel
watch case backs!.
As far as I know there is no such thing as an assortment of watch backs or
even standard sizes.... which effectively means you have to have one
specially machined, or.... use whatever you get your hands on, and design
the watch around it!!

I would be interested to see how you get on.
Bernard Bryce

-----Original Message-----
From: owner-rp-ml@rapid.lpt.fi [mailto:owner-rp-ml@rapid.lpt.fi]On Behalf Of
Ricardo Amaral
Sent: 09 April 2008 20:46
To: rp-ml@rapid.lpt.fi
Subject: Re: [rp-ml] Watch Cases
Hi Lloyd,

AFAIK in any casted fabrication contact surfaces need to be machined,
threading included.

A watch runs in really tight tolerance, way thinner than a Solid-Scape
system can deliver (I have a couple). I don't know the correct english
terms, but you should design it with extra material enough to be machined
later, and would use it around 3 or four times the Solid-Scape tolerances
thick.

And I don't think internal gearing should even be considered for casting, if
you are thinking of that.

Ricardo

Date:Wed, 09 Apr 2008 09:29:22 -0400
From: lloyd@grosbard.com
To: <rp-ml@rapid.lpt.fi>
> HI, I Have a solidscape machine at my disposal and now need to
> design watch cases, and actual design and output is not a problem.
> What I need to know is how to obtain precise specifications, for
> movements and faces so I can design around them...also.
>
> Is the screw for threading case and back done in the model or
> machined afterward?
>
> If it is cast from a solidscape model can it be precise enough to
> be waterproof?
>
>
> Thanks
>
> Lloyd
>
>
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Received on Thu Apr 10 10:40:19 2008