Machinist in the house?

"George" wrote in message
...
Delrin or nylon...you can buy sheets from MSC-Direct.com


George,

Since the original post asked for a material that is more stable than
cherry, I wonder about the high thermal expansion of Delrin and nylon. No
questions that you suggstions are close to wood in machinability. They are
also several times higher in expansion than most wood and metal, and some
plastics (nylon for sure) absorb a lot of moisture. The requirements were
pretty loosely stated for sure. Any thoughts?

PSsquare

In article ,
(Winfried Buechsenschuetz) wrote:

(jjs) wrote in message
...

If you can nudge me in the right direction, offline if it is
appropriate, I would be quite greatful.

You mentioned that your camera hardly has any flat surfaces. So I
think it will take numerical controlled (NC or CNC) machines to
manufacture your design. There are quite a few machine shops which do
not manufacture any devices but only components for other companies,
and they will be happy to receive such an order because it will bring
them some money. [...]

Yes, CNC shops are common. Unfortunately, I am going to make all of _two_
(maybe three) of these cameras and having a comercial shop make the parts
would be hugely expensive. In any event, I'm still in the advanced
prototype stage and can cut the parts at home until/if it proofs out. It
may never make it past the hand-cut stage.

FWIW, check out these folks: http://www.emachineshop.com
Very cool business. They have made things for me that I've designed using
their software. But in that case we were talking about dozens of copies of
each item, not two of each.

In article , "PSsquare"
wrote:

"George" wrote in message
...
Delrin or nylon...you can buy sheets from MSC-Direct.com


George,

Since the original post asked for a material that is more stable than
cherry, I wonder about the high thermal expansion of Delrin and nylon. No
questions that you suggstions are close to wood in machinability. They are
also several times higher in expansion than most wood and metal, and some
plastics (nylon for sure) absorb a lot of moisture. The requirements were
pretty loosely stated for sure. Any thoughts?

Nylon absorbs a lot of moisture? See how ignorant I am. I thought plastics
and nylon were virtually impervious to water. Monday I will go to our
university materials research library and study up so that I don't have to
pester you all.

The requirements a to be stronger than cherrywood, as easy to cut as
wood (even if it's harder to cut than cherry). It must be able to stand up
to direct sunlight in hot weather without weakening (or weaping) and also
stand up to temperatures of -20F with no greater possiblity of snapping
than cherry. Dimensional changes due to moisture - well, no worse than
cherry. Weight is not an issue.

"jjs" wrote:

The requirements a to be stronger than cherrywood, as easy to cut as
wood (even if it's harder to cut than cherry). It must be able to stand up
to direct sunlight in hot weather without weakening (or weaping) and also
stand up to temperatures of -20F with no greater possiblity of snapping
than cherry. Dimensional changes due to moisture - well, no worse than
cherry. Weight is not an issue.

Maple.

David J. Littleboy
Tokyo, Japan

"jjs" wrote in message
...
In article ,
(Winfried Buechsenschuetz) wrote:

(jjs) wrote in message
...

If you can nudge me in the right direction, offline if it is
appropriate, I would be quite greatful.

You mentioned that your camera hardly has any flat surfaces. So I
think it will take numerical controlled (NC or CNC) machines to
manufacture your design. There are quite a few machine shops which do
not manufacture any devices but only components for other companies,
and they will be happy to receive such an order because it will bring
them some money. [...]

Yes, CNC shops are common. Unfortunately, I am going to make all of _two_
(maybe three) of these cameras and having a comercial shop make the parts
would be hugely expensive. In any event, I'm still in the advanced
prototype stage and can cut the parts at home until/if it proofs out. It
may never make it past the hand-cut stage.

FWIW, check out these folks: http://www.emachineshop.com
Very cool business. They have made things for me that I've designed using
their software. But in that case we were talking about dozens of copies of
each item, not two of each.

John,
Thanks for that link! I've been looking for an effective way to prototype
something I've been working on and it looks like this company may well be
exactly what I need.
Very cool.

Sherman
http://www.dunnamphoto.com

"jjs" wrote in message
...
The requirements a to be stronger than cherrywood, as easy to cut as
wood (even if it's harder to cut than cherry). It must be able to stand up
to direct sunlight in hot weather without weakening (or weaping) and also
stand up to temperatures of -20F with no greater possiblity of snapping
than cherry. Dimensional changes due to moisture - well, no worse than
cherry. Weight is not an issue.

Fiberglassing makes wood impervious to moisture. They use that in exterior
hulls of ocean going vessels. I'm guessing, but that seems to be pretty
extreme duty. Sea kayaks are made from 1/8" cedar strips, glassed inside and
out. Maybe a combination of fiberglassed wood and machined plastics for the
mating surfaces. Or just plain fiberglass on carved foam cores...

In article , "Sherman"
wrote:

"jjs" wrote in message
...
FWIW, check out these folks: http://www.emachineshop.com
Very cool business. They have made things for me that I've designed using
their software. But in that case we were talking about dozens of copies of
each item, not two of each.

John,
Thanks for that link! I've been looking for an effective way to prototype
something I've been working on and it looks like this company may well be
exactly what I need.
Very cool.

The entrepeneur is a very good programmer and machinist. The software is
updated regularly and gets better every couple of weeks. If I may suggest
that you put together a quick version of a part and run it through to the
pricing stage. When you see the cost of one part (say, $120), then check
the cost of 20 parts. Chances are good the total for the 20 parts is as
little as $150. That's CNC.

I love it when the software interrupts and says things like "If you reduce
the number of splines, you will save money" or "you have two different
sized holes. Make them the same and you will save money" or "You have
exceeded the recommended span for this material. Try..."

In article , "MikeWhy"
wrote:

Fiberglassing makes wood impervious to moisture. They use that in exterior
hulls of ocean going vessels. I'm guessing, but that seems to be pretty
extreme duty. Sea kayaks are made from 1/8" cedar strips, glassed inside and
out. Maybe a combination of fiberglassed wood and machined plastics for the
mating surfaces. Or just plain fiberglass on carved foam cores...

I appreciate the thought, Mike.

Glass hulled ocean kayaks, yes. Love 'em. Good ones have an ideal
combination of wood and glass. We have some kevlar, composites, wooden
and glass boats here. This is the home of Winona Canoe. (Winona,
Minnesota) My colleague's brother is the founder and owner. Composites
rule.

Back to the cameras - It uses relatively small parts, and fiberglass in
this case is a huge nuisance to cut, and not strong on thin part edges. I,
talked with our composites material engineer and they have nothing mass
produced (eg; affordable) that works in this scale for prototyping. If
this were a NASA project, I'd certainly have learned more and would have
heard "make it so", but for my small, amateur needs, the correct
composites are a dream.

Thanks for the good words.

EEEeeek!! I will backup that page, with credits to you of course, on the
MF megasite. Let me know of any other pages which can/should be archived
too! I would _really_ hate to see such great and inspiring homebrewing
pages to be lost or not available...
============

Actually, Roger Hicks in an article in Brit. Jrnl of Photogr. some years
ago (reprinted in his MF/LF handbook IIRC?) described a LF fisheye using
the kiev 30mm lens as the optic and a thin body with leaf shutter and
mounting for ground glass or film 4x5" holders. I like the idea, esp.
since you should be able to dismount the lens when needed on say a Kiev 60
;-)

Much as I like the Walker Titan design ideas, the cost at $2k or so is
problematic ;-) The cambo wide body only is still $1k. Since I am
intending to use a surplus 90mm angulon ($100-ish in shutter ;-), it
doesn't make sense to mount it on a body costing ten or twenty times as
much ;-) Esp. since I don't need those shifting features ;-) But I would
like something where a rollfilm back is an option (hence, on topic in MF
NG).

I still find it amazing that postcard folders of 100 years ago had front
lens standard shifts etc. and covered 3+x5 1/2" rollfilm, folded into a
jacket pocket; yet today, we can't find anything close ;-) and ;-( ;-)

bobm
--
************************************************** *********************
* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
********************Standard Disclaimers Apply*************************

Bob Monaghan wrote:
...
Actually, Roger Hicks in an article in Brit. Jrnl of Photogr. some years
ago (reprinted in his MF/LF handbook IIRC?) described a LF fisheye using
the kiev 30mm lens as the optic and a thin body with leaf shutter and
mounting for ground glass or film 4x5" holders. I like the idea, esp.
since you should be able to dismount the lens when needed on say a Kiev 60
;-)

Such a hack was reported with pictures in the Finnish Kamera-lehti
magazine. Essentially it was just a wooden box with 4x5" lens panel and
film holder. Makes nice round images. One of the tricks was to mount the
shutter backwards inside the camera, and use a cable release to trip it.

-- Lassi