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Bob S[_2_] Bob S[_2_] is offline
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Default New Proxxon lathe question #1

Thank you for the very comprehensive suggestions!

Comments interspersed below:


On 4 Mar 2012 06:24:57 GMT, DoN. Nichols wrote:

On 2012-03-04, Bob S wrote:
Background:

I have been messing with camera lenses and was talking about getting a
lathe to make some adapters and maybe learn something and have fun.
(If I just wanted adapters it would be far less expensive to just pay
someone to make them.)

My wife pre-empted my dithering about the "best" choice and got me a
Proxxon 230 as a birthday present. So now I get to dither about
accessories instead.


What is its native threading system? For most lens adaptors,
you will want metric threading capability.

O.K. According to this:

http://www.proxxon.com/eng/html/24004.php

it is metric.

You'll want the boring tool set -- since you need to bore the
center out of your adaptors.

No need for the die holder -- you'll be cutting non-standard
threads for which you could not afford a tap or die. :-)

The quick-change toolpost will be a big hell as you switch
between turning and threading tools (internal and external). Get extra
holders. I see four total to be a good choice for what you want to do.

Both the 3-jaw chuck and the 4-jaw chuck will be good to have.
But the lathe comes with the 3-jaw, so you don't need another until you
start milling with a rotary table. And I don't see that as needed for
what you are doing.

Hmm ... if you are going to make bayonet mounts (which many
cameras use for their lenses), you will want the milling capability, and
the rotary table down from the milling section. I don't see a rotary
table listed, so you would have to get one from the Sherline folks to
have one of reasonable size.


I would probably take bayonet mounts from junk lenses and bodies. But
I can see that milling and a rotary table might come in handy for many
things. My father donated an old Unimat II (not threading, but it will
convert to a mill), and amazingly I have a very small rotary table
from a yard sale!



No need for the collet set for what you have specified you want
to do --but as you get to doing other things, it will me nice to have.

The fixed steady is probably not big enough for most adaptors or
extension tubes.

The three piece thread cutting set for sure. (And learn to
grind your own tools from HSS lathe blanks.

So, my first question is hopefully simple; should I get the Proxxon
splash shield / chip catcher tray gadget? It looks like a sensible way
to reduce mess, but I have no lathe experience.


Where are you going to be setting up? I don't see you needing
to use flood coolant, so the splash part you don't need. If you're
going to be doing this in the dining room or other living part of
the house, the assembly could help control where the chips go, so you
can clean them up more easily.

I see you likely to be using aluminum and brass, neither of
which really need flood coolant, and the aluminum can benefit from a bit
of WD-40 spritzed on as coolant, while the brass cuts dry very nicely.
Brass makes nicer and smoother threads, but it costs more and weighs
more.

If you don't already have one, get a shop vac to clean up the
chips.


And in addition to the listed things on that site, you will also
need:

0) *Absolutely* -- safety glasses for yourself, and for whoever
comes to look over your shoulder. Spares for when the original
ones get too dirty to see through.

1) Micrometers in mm (since the lathe is calibrated in mm). At
the least 0-25 mm and 25-50 mm. The maximum capacity of the
lathe barely goes over 50 mm, so probably not the 50-75 mm one.


Yes, I only have an inch micrometer so far...

The 52mm specification is European style, giving the radius not the
diameter of the swing over bed.


2) Thread pitch gauges for metric threads.

3) Digital caliper will be convenient for quick measurements
and for converting between inch and metric dimensions. Typical
inexpensive ones go from 0-150 mm (0-6"). They will eat up
batteries quickly, so plan to use SR357 or SR44 in place of the
original LR357 or LR44 cells. They will last longer, at least.

Beware that the "off" button does not really turn it all off,
just the LCD display. It still keeps running internally to keep
track of when it is moved, so it has the right reading when you
turn it back "on".

You can't trust it to provide as much accuracy as the
micrometers, but it is quick to use and read.

4) A scissors style knurling tool to allow knurling parts for grip.
A "bump" style knurling tool needs a much heavier and more rigid
lathe to drive it.


Great idea; I hadn't thought of that.

5) A bench grinder for making your own threading tools and other
turning tools -- and for re-sharpening what you buy.

Probably lots of other things, but these are what I can think of
at the moment.

Certainly others will think of other things. FWIW, I have made
lens adaptors in the past, and expect to make more. I've even made some
with a much less capable lathe.

Good Luck,
DoN.