开云体育

The saphire ball bearing makes an excellent lens for a diode laser.

Victoria Welch <wrlabs@...> wrote: On Saturday 14 April 2007, born4something wrote:
> --- In 7x12minilathe@..., Victoria Welch <wrlabs@...>
>
> wrote:
> > Just wondering if thinking of this as a waveguide (as in microwave
> > radio) might be appropriate?!? Hummm....
>
> Hi Vikki,
>
> It is a waveguide but I doubt you'll drill a hole fine enough that
> you need to design it as such. While ever your tolerances exceed a
> wavelength you won't be in the race!

:-) I was wondering just how to drill something out to ~650nM :-). I've
got some *tiny* PCB drils but I don't think those are even in the
running :-).

> Your comments about being able to achieve a very good pin spot at any
> given distance but circles elsewhere make me think your source is off
> axis and you are projecting cones of light. You can set the
> convergent apex of the cone but it's still a cone. I haven't been
> following all of this thread in detail but does that gel?

Yes Sir, it does.

For $1 each including batteries (some ~$4, some ~$7) they are all crappy
in terms of beam and every one is noticeably different in the spot it
produces. Just how good those little plastic collimating lenses are is
a whole different story. I'd bet that the laser LEDs that go into
those thing are not pick of the production run and the most that can be
said about them is that they do emit from someplace on the device and
at varying intensity as well.

Sorta like antenna work, So many variables :-).

Will be interesting to see what this one from Micro-Mark is like.

Take care, Vikki.
--
Victoria Welch, WV9K/7
"Certainly the game is rigged. Don't let that stop you; if you don't
bet, you can't win." --Lazarus Long






---------------------------------
Ahhh...imagining that irresistible "new car" smell?
Check outnew cars at Yahoo! Autos.

On Saturday 14 April 2007, born4something wrote:

--- In 7x12minilathe@..., Victoria Welch <wrlabs@...>

wrote:

Just wondering if thinking of this as a waveguide (as in microwave
radio) might be appropriate?!? Hummm....

Hi Vikki,

It is a waveguide but I doubt you'll drill a hole fine enough that
you need to design it as such. While ever your tolerances exceed a
wavelength you won't be in the race!

:-) I was wondering just how to drill something out to ~650nM :-). I've
got some *tiny* PCB drils but I don't think those are even in the
running :-).

Your comments about being able to achieve a very good pin spot at any
given distance but circles elsewhere make me think your source is off
axis and you are projecting cones of light. You can set the
convergent apex of the cone but it's still a cone. I haven't been
following all of this thread in detail but does that gel?

Yes Sir, it does.

For $1 each including batteries (some ~$4, some ~$7) they are all crappy
in terms of beam and every one is noticeably different in the spot it
produces. Just how good those little plastic collimating lenses are is
a whole different story. I'd bet that the laser LEDs that go into
those thing are not pick of the production run and the most that can be
said about them is that they do emit from someplace on the device and
at varying intensity as well.

Sorta like antenna work, So many variables :-).

Will be interesting to see what this one from Micro-Mark is like.

Take care, Vikki.
--
Victoria Welch, WV9K/7
"Certainly the game is rigged. Don't let that stop you; if you don't
bet, you can't win." --Lazarus Long

On Saturday 14 April 2007, born4something wrote:

--- In 7x12minilathe@..., Victoria Welch <wrlabs@...>

wrote:

Please don't laugh too hard :).

Not laughing Vikki. Handles are seriously useful from an OH&S
viewpoint as well as comfort. But make sure they fit solidly. Just
imagine filing energetically and dislodging a handle such that the
tang is driven up inside your wrist on the next power stroke.
Similarly when using in the lathe and something grabs unexpectedly.
With that in mind, I need a few more handles and to refit some more
securely!

I drilled out the shank in two steps, deep for the thin end and another
at the top for the big end near the file itself. I don't know if that
helped or that cheap wood is just so springy that it comes down on the
shank tightly?!? Short of pounding it off with a hammer of some sort,
I think it is there to stay.

Just put it over the file shank and popped it down on the workbench.
Maybe there is a place for crap wood ;-)?

Take care, Vikki (pleased not be be laughed at :-).
--
Victoria Welch, WV9K/7
If you think education is expensive, try ignorance" --Andy McIntyre and
Derek Bok

On Saturday 14 April 2007, born4something wrote:

--- In 7x12minilathe@..., Victoria Welch <wrlabs@...>

wrote:

Shipping isn't real bad, it is costing me almost $30 here :-).

Hi Vikki,

Are you being ripped off on freight? I just ordered one from Micro-
Mark and it came to $US30.88 (19.95+10.93 freight). I'm in Oz too so
when Ian said $40 total that would be Aussie dollars. If you're
paying the same as us I sure hope it's express delivery. M-M say 4 -
12 weeks for international. :-(

Dunno, apparently not $28.90 ($19.95+$8.95 shipping). They are in New
Jersey so WA state is not all that much closer than Oz ;-).

Never mind, you'll have posted all the neat extra tricks by the time
we get ours (and ours will have flat batteries by the time they
arrive, LOL). Thanks for the link - and the discount Ian spotted!

Hopefully it will be simple enough that there won't be any ;-).

Probably the one I am most interested in with this thing is setting the
lathe tools on center and using it to adjust the tailstock. The mill
stuff is just gravy :-).

Should be a lot of fun and if it works at all, a lot quicker.
Fortunately I just ordered a full set of MT2 collets so I won't have to
depend on the supplied drill chuck for the mill.

Should be fun under any conditions, plus it might give me ideas!

Take care, Vikki.
--
Victoria Welch, WV9K/7
"The best minds are not in government. If any were, business would hire
them away." - Ronald Reagan

On Saturday 14 April 2007, Ian Foster wrote:

G'day John & Vikki et al.

I hope Micro Mark have container load of these things; I think I've
started a rush.
If some one for MicroMark is reading this, I would like a commission!

One good turn deserves another (Commission?).

Hey! I found the link, I want my cut too </politician> :-). LOL!

Take care, Vikki.
--
Victoria Welch, WV9K/7
"Life has meaning only in the struggle. Triumph or defeat is in the
hands of the gods...so let us celebrate the struggle!" -- Swahili
Warrior Song

On Saturday 14 April 2007, Clint D wrote:

Vickie

Thank you, I had look thru their site and never found it till you
provided the info.
Clint

Glad to help!

I knew I had seen two different ones of these things, but I wasn't sure
where, I thought it was MM, but I spent some time rooting around
different sites and then at MM and am still not sure how I found
it :-). Glad I persisted though :-)!

Take care, Vikki.
--
Victoria Welch, WV9K/7
'Never argue with an idiot. They drag you down to their level then beat
you with experience.' --Cecil Bayona

Vickie

Thank you, I had look thru their site and never found it till you
provided the info.
Clint


Victoria Welch wrote:

G'day John & Vikki et al.

I hope Micro Mark have container load of these things; I think I've
started a rush.
If some one for MicroMark is reading this, I would like a commission!

One good turn deserves another (Commission?).
Regards,
Ian.

--- In 7x12minilathe@..., Victoria Welch <wrlabs@...>
wrote:

Shipping isn't real bad, it is costing me almost $30 here :-).

Hi Vikki,

Are you being ripped off on freight? I just ordered one from Micro-
Mark and it came to $US30.88 (19.95+10.93 freight). I'm in Oz too so
when Ian said $40 total that would be Aussie dollars. If you're paying
the same as us I sure hope it's express delivery. M-M say 4 - 12 weeks
for international. :-(

Never mind, you'll have posted all the neat extra tricks by the time
we get ours (and ours will have flat batteries by the time they
arrive, LOL). Thanks for the link - and the discount Ian spotted!

John

--- In 7x12minilathe@..., Victoria Welch <wrlabs@...>
wrote:

Please don't laugh too hard :).

Not laughing Vikki. Handles are seriously useful from an OH&S
viewpoint as well as comfort. But make sure they fit solidly. Just
imagine filing energetically and dislodging a handle such that the
tang is driven up inside your wrist on the next power stroke.
Similarly when using in the lathe and something grabs unexpectedly.
With that in mind, I need a few more handles and to refit some more
securely!

John

--- In 7x12minilathe@..., Victoria Welch <wrlabs@...>
wrote:

Just wondering if thinking of this as a waveguide (as in microwave
radio) might be appropriate?!? Hummm....

Hi Vikki,

It is a waveguide but I doubt you'll drill a hole fine enough that you
need to design it as such. While ever your tolerances exceed a
wavelength you won't be in the race!

Your comments about being able to achieve a very good pin spot at any
given distance but circles elsewhere make me think your source is off
axis and you are projecting cones of light. You can set the convergent
apex of the cone but it's still a cone. I haven't been following all
of this thread in detail but does that gel?

John

On Friday 13 April 2007, Clint D wrote:

Ian
what item number was that?
Clint

Item Number: 83432

Link to page:



Being that it is on closeout I figured I fill in for Ian :-).

Take care, Vikki (who has nothing to do with MicroMark other than being
a brand new customer :-)
--
Victoria Welch, WV9K/7
"We are not fighting so that you will offer us something. We are
fighting to eliminate you." --Hussein Massawi, a former Hezbollah
leader

On Friday 13 April 2007, viajoaquin@... wrote:

I recall something about the material through which a pinhole is made
as having to be at least the same thickness as the diameter, in order
to properly "funnel" the lazer down a cylindrical hole. Maybe
drilling a precise, tiny hole through something thick, rather than
using foil, would be worth a try to clean up the dot. Roy

Thanks Roy, will see what I have that will serve in the shop and let you
know how it works out, perhaps slugs from some of the 3/8" round AL
might work.

Just wondering if thinking of this as a waveguide (as in microwave
radio) might be appropriate?!? Hummm....

Take care, Vikki.
--
Victoria Welch, WV9K/7
Experience gives the test first and the lesson afterwards. -- Unknown

On Friday 13 April 2007, Ian Foster wrote:

G'day Roy, Vikki, et al.
Laser beams being coherent light will diffract around thin objects;
yes light bends. A thicker a long pinhole would be needed preferably
with non specular reflecting sides. As I Read Vikki's post this
morning I experimented with a laser pointer and a business card with
a pin hole in it. Having the laser a little way away from the card
allowed me to direct a thin beam on to the curtains about 400mm (16")
away. Laser pointers need a larger diameter beam so they can be seen
on a screen; contradictory to what we require for edge and centre
finding.

I was going to grab something thicker and try that based on
recommendations here. I'll probably still putz with it just for
jollies.

Thanks to Vikki's post I looked up the MicroMark link and purchased a
LC/EF on the spot; USD19.95; it will cost me AUD40 by the time it
gets to me in Oz. Thanks Vikki!

Thank you! I didn't even notice that, they dropped the price by $20!
Went back and ordered one myself at that price. We can compare
notes :).

I'm pretty sure I have spent at least that much on cheap laser pointers
so far :-).

Shipping isn't real bad, it is costing me almost $30 here :-).

Thanks for the wakeup :-).

Just for fun I took that junk wood dowel and made myself a nice little
file handle. Not perfect but the next one will be closer :-). I'm
also going to get some better wood next time I am at one of the home
improvement stores.

I tried out using the boring bar holder for the QCTP and it worked, not
ideal I don't think but it sure is simple and easy :). I forget who
showed me that here <blush> but Thanks!

In case anyone is interested, I put the pix up on the machine shop page
(top of projects). Please don't laugh too hard :).



Take care, Vikki.
--
Victoria Welch, WV9K/7
"Theres nothing to writing. All you do is sit at a typewriter and open a
vein." -- Red Smith

Ian
what item number was that?
Clint


Ian Foster wrote:

G'day Roy, Vikki, et al.
Laser beams being coherent light will diffract around thin objects;
yes light bends. A thicker a long pinhole would be needed preferably
with non specular reflecting sides. As I Read Vikki's post this
morning I experimented with a laser pointer and a business card with
a pin hole in it. Having the laser a little way away from the card
allowed me to direct a thin beam on to the curtains about 400mm (16")
away. Laser pointers need a larger diameter beam so they can be seen
on a screen; contradictory to what we require for edge and centre
finding.
Thanks to Vikki's post I looked up the MicroMark link and purchased a
LC/EF on the spot; USD19.95; it will cost me AUD40 by the time it
gets to me in Oz. Thanks Vikki!

One good turn deserves another.
Regards.
Ian

--- In 7x12minilathe@..., viajoaquin@... wrote:

I recall something about the material through which a pinhole is

made as having to be at least the same thickness as the diameter, in
order to properly "funnel" the lazer down a cylindrical hole. Maybe
drilling a precise, tiny hole through something thick, rather than
using foil, would be worth a try to clean up the dot.

Roy

-----Original Message-----

I recall something about the material through which a pinhole is made as having to be at least the same thickness as the diameter, in order to properly "funnel" the lazer down a cylindrical hole. Maybe drilling a precise, tiny hole through something thick, rather than using foil, would be worth a try to clean up the dot.
Roy

G'day Jim.
Have you seen my message #19558? Your comments could be very helpful to
others in getting the best from their lathes.
"Jim RabidWolf" <unclerabid@...> wrote: "No, they are by no means
primative,..."
I agree with your views regarding the quality issue and the country of
origin. It would be very unwise to dimiss the Chinese and their
capabilities. Its been done before and "Pearl Harbour" was the out
come; likewise the WTC New York. (Enough OT)

Thanks for your knowledge?

One good turn deserves another.
Regards
Ian

There is an improved type of small/mini-lathe on the market that deals with a lot of these points it is made from better materiials, is a little bigger and heavier so more rigid, better finssh and tolrances so it has better accuracy too. The speed control is a bit rudimentary and it does unfortunately cost a little more.

Its called a Myford ML Super 7, yours for a bargain ?25,000 bucks or so plus shipping.

Little outside my league and most others too.

Certainly makes me appreciate the Chinese designners and workers.

Gerry
Leeds UK

From: "Jim RabidWolf" <unclerabid@...>
Reply-To: 7x12minilathe@...
To: <7x12minilathe@...>
Subject: Re: [7x12minilathe] Re: circuit board diagram
Date: Fri, 13 Apr 2007 15:31:09 -0500

No, they are by no means primative, but the quality of SOME of the
electronic componenets leaves a lot to be desired. The capacitors,
especially, are NOT of the finest quality. The later models, while better,
are still not packed with the finest quality. When I replace cap's I use
Nichicon or Panasonic almost exclusively - just changing the caps in certain
areas makes a drastic difference.

By changing out the output transistors with units that not only have a
higher current rating, but a faster turn on time and lower turn on
resistance, you can not only squeeze a bit more power out of them, the
performance is improved. You can literally hear the difference in the motor.

In defense of the manufacturer, they build to spec - what ever the end
seller requests, and they pay for, they get. That is why there are some with
Chinese made controllers and some with American made - it's all in what the
order requires - that includes fit and finish - you can buy anything from a
rough castings set to a very finely tuned unit - don't blame SIEG, et al,
they are merely filling the orders given them.

All in all, the Asisan lathes and mills are a bargain. That being said,
depending on what the distributor ordered, you need to do a bit of fit and
polish to ge the unit within your own specifications and what you're willing
to live with. The factories can turn out any quality and quantity ordered -
if there's a problem, it's generally due to what was ordered in the first
place.

Having worked on so many of the boards, and seen th evolution of them, I
have great admiration for SIEG, et al, and the products they poduce. Like
any thing built - someone may find a way to make it just a little bit
better. Hopefully soon, Uncle Rabid will be moving along to not only repair
the boards, but produce our own, plus more addons to make our little
machines just a little more useful.

Jim RabidWolf
Uncle Rabid ( )
We Repair Electronic Speed Controllers
For Asian Mini Lathes and Mini Mills
"Just Crazy Enough To Get the Job Done"
----- Original Message -----
From: "gerry waclawiak" <gerrywac@...>
To: <7x12minilathe@...>
Sent: Friday, April 13, 2007 6:46 AM
Subject: Re: [7x12minilathe] Re: circuit board diagram

I think your right with your general assessment of the small lathes, they
are built down to a budget price that people are prepared to pay as a
semi-disposable item. The big demand is not from dedicated machinists

who

demand a top quality product but for something that is workmanlike and
affordable. Many of the UK importers seem to provide US made boards as
standard which might say something about the standard ones Chinese ones

as

bring a weak point. The Chinese may not be at the absolute cutting edge

of

technology but they are nowhere near as primitive as some people make

out.

Gerry
Leeds UK

From: Michael Taglieri <miket--nyc@...>
Reply-To: 7x12minilathe@...
To: 7x12minilathe@...
Subject: Re: [7x12minilathe] Re: circuit board diagram
Date: Fri, 13 Apr 2007 01:08:32 -0500

I didn't mean to put down Chinese in general. They can do anything they
put their minds to and have their own space program now. But this
particular factory designed and constructed these lathes to sell as

cheap

as possible (which is why so many of us can afford them), and they have
many out-of-the-box flaws. I can understand and largely correct the
mechanical ones, but there are also well-documented areas of
corner-cutting, cheap components, bad solder joints, etc., in the
electronics, an area I don't know much about and (more important), have
no desire to learn more about. I'd rather pay to have this area fixed
right than try to fix it myself and possibly screw up.

Mike Taglieri miket--nyc@...

Everyone has his reasons.
- Jean Renoir "The Rules of the Game"


On Thu, 12 Apr 2007 11:49:59 +0100 "Hugh" <hughlss@...>
writes:

Mike,
Don't be offended, but I'm going to pick-up on what you said about
the Chinese. If there's one nation of people on this earth that will
give the customer what he wants, it's the Chinese. The average
worker lacks the skills maybe, and, of course, we want their
low-cost goods - but it's not the same thing as not caring about
what customers want. Tell them and they will fix it. I should know -
I import container loads of machine tools and they bend over
backwards to put things right whenever there's a problem.
Hugh
----- Original Message -----
From: Michael Taglieri
To: 7x12minilathe@...
Sent: Thursday, April 12, 2007 9:17 AM
Subject: Re: [7x12minilathe] Re: circuit board diagram


I'm beginning to think boosting Rabid's business isn't such a bad
idea.
Uncle Rabid, how much would you charge to take my controller, beef
up all
the crap circuit-board parts and tweak the pots for maximum safe
torque
and minimum safe speed, i.e, the way the Chinese would have done
if they
gave a shit? (And do you need just the controller box, or my
motor
also?)

I'm normally an extremely do-it-yourself kind of guy, but the more
I read
here about adjusting your controller at home, the less sure I am
of doing
it right without frying something. I'd rather let someone do it
who
knows how and stick to the machining that I'm good at.

Mike Taglieri miket--nyc@...

Everyone has his reasons.
- Jean Renoir "The Rules of the Game"

On Mon, 02 Apr 2007 12:26:17 -0000 "born4something"
<ajs@...> writes:
> Hi Ian,
>
> I'd be talking more to Uncle Rabid before looking to buy a new
> board. He's the local oracle and repairs them for a living. He's

> strangely generous with his advice around here given that he
could
> just play his cards close and boost his business. I think he
> actually likes being helpful! If he can't talk you through he'll
fix
>
> it for you for a pretty reasonable fee anyway.
>
> The other reason for running things past Uncle is that he deals
with
>
> most (all?) the variants on these controllers. Most of us only
> experience one or two of them. Some are FET based and others
SCR.
> Some use relays and others don't. Mine has no relays but those
5-pin
>
> blocks are sounding like 24V coil relays. Two for the coil and
three
>
> for the changeover contact set.
>
> John
>
>
> --- In 7x12minilathe@..., Ian Fletcher
> <ian.fletcher@...> wrote:
> >
> > Hi John, thanks for the warning. I was unable to get a reading
off
>
> the second resistor so have ordered two. Visually I cannot find
any
>
> damage to the board or components apart from what looks like
> mechanical damage to one of the two square yellow blocks marked

> HR54H-S-DC24V which seem to have 5 legs, which I take to be
voltage
>
> convertors? As you can see although capable of soldering and
> unsoldering small components I am not always able to identify
what
> they are!! If I do need to bite the bullet and buy a new board
are
> they all the same from different manufacturers? I know Clarke
lathes
>
> are more expensive that others and wondered if the circuit board

> would be cheaper from other makers. Thanks Ian
> > -----Original Message-----
> > >From: born4something <ajs@...>
> > >Date: Sun Apr 01 08:02:37 GMT 2007
> > >To: 7x12minilathe@...
> > >Subject: [7x12minilathe] Re: circuit board diagram
> >
> > > Hi Ian,
> > Just a thought. Might not be what you want to hear. If only
one
> > > resistor is burnt out and they are in parallel as a 0.33 ohm
for
>
> > > current sensing then the machine should run, but overload
sense
>
> at
> > > half load. So either BOTH resistors have failed or there is

> > > something else failed too.
> > > John
> > > --- In 7x12minilathe@..., Ian Fletcher
> > > <ian.fletcher@> wrote:
> > > >
> > > > Thanks for advice, resistors ordered at cost of ?,?1 so
if
> that is
> > > all that is wrong I shall have saved ?,?84 !! Thanks for
your
> > > interest and support. Ian
> > > > -----Original Message-----
> > > > >From: born4something <ajs@>
> > > > >Date: Fri Mar 30 08:07:03 GMT 2007
> > > > >To: 7x12minilathe@...
> > > > >Subject: [7x12minilathe] Re: circuit board diagram
> > > >
> > > > > Hi Ian,
> > > > > 66 ohms sounds a bit high. You may have tricked people
with
>
> that
> > > > > space between the R and 66. Electronics types often use
the
>
> > > prefix
> > > > > as a decimal point (like 1k2 means 1.2k-ohms) and when
there
>
> is
> > > no
> > > > > prefix they just insert the base symbol, R. So R66 is
likely
>
> > > 0.66
> > > > > ohms. It's a convenient notation and avoids using those

> little
> > > dots
> > > > > that don't print clearly and are often multiplied when
> > > photocopying
> > > > > stuff!
> > > > > Check the other resistor. If it is 0.66 ohms I'd expect

> quite a
> > > > > reasonable reading in circuit without even unsoldering
it as
>
> the
> > > > > surrounding components are unlikely to be anywhere near
as
> low
> > > as
> > > > > that. If they are, it's likely a failed FET or triac,
> depending
> > > on
> > > > > your model.
> > > > > John
> > > > > --- In 7x12minilathe@..., andrew franks
> <andyf1108@>
> > > > > wrote:
> > > > > >
> > > > > > Looks as though it might be: 5W = 5 watts, R66 = 66
ohm.
> Not
> > > sure
> > > > > about the J, though - could represent a tolerance (as in

> plus or
> > > > > minus a certain percentage from the marked resistance
> value).
> > > > > However, 66 ohms isn't a standard "preffered" value - 68

> ohms
> > > is,
> > > > > though. Can you unsolder its twin, if it has identical
> markings,
> > > and
> > > > > check it? If it is 66 ohms, you may have to use a couple
of
>
> 33
> > > ohm
> > > > > ones, and connect them in series (though if you use 68
ohms,
>
> > > it's
> > > > > probably close enough).
> > > > > > As to wattage, if you can't get 5 watts from Maplin or

> > > > > somewhere, get the next size up.
> > > > > > I wonder what made it burn out, though? Hopefully, it

> was
> > > > > something simple like a short circuit caused by swarf.
> > > > > > Andy
> > > > > > ftr1d <ian.fletcher@> wrote:
> > > > > > Hi, I have just purchased a 240 volt Clarke 300m
>
> > > with a
> > > > > dead circuit
> > > > > > board. A new board will cost ?,?85 so I am looking to

> repair
> > > it. The
> > > > > only
> > > > > > fault I can see is a blown ceramic block, one of a
pair,
> which
> > > is
> > > > > > marked 5WR 66J and is in R1 position on the board. I
> assume it
> > > is
> > > > > a
> > > > > > creamic resistor? Does anyone have a circuit diagram
or
> can
> > > give
> > > > > me the
> > > > > > specification of the part. Thanks Ian
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > ---------------------------------
> > > > > > New Yahoo! Mail is the ultimate force in competitive
> > > emailing.
> > > > > Find out more at the Yahoo! Mail Championships. Plus:
play
> games
> > > and
> > > > > win prizes.
> > > > > >
> > > > > >
> > > >
> > > >
> >
> >
>
>
>
>
> Be sure to check out for small

> mills and lathes.
> Yahoo! Groups Links
>
>
>
>
>

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Be sure to check out for small
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Be sure to check out for small mills

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On Friday 13 April 2007, Abby Katt wrote:

I have one of these laser-center finders - best money I spent in a
long time.

So it struck me too. Having more time than $$$ I just thought I would
see what could happen with trying to make one myself.

They're more than just a laser-pointer (which produces a massive
dot),

Yes, they do, I've done much putzing around with pinhole "lenses" of
various sizes and while they help, they still seem to produce a
huge "dot", well more of an inconsistent sorta kinda blob / smear.
Some of the laser pointers produce a better "dot" than others, but none
I have tried so far (around 5 now) have a seriously good dot.

I'm not complaining about the laser pointers not being perfect, I knew
that going in but it would certainly be nice if this did work out.

One of the problems seems to be getting the pinhole aligned, it looks
like it should be easy and the pinhole arrangement itself should help
(it DOES help), but it isn't working to my satisfaction (yet?).

I'm wondering if the circle I can get easily would do? Alignment is an
issue even with 4 equally spaced set screws around the top and
bottom(ish) of the holder. I've spent a lot of time aligning the
device and I can get it *really* close to concentric at a given
distance but it turns into a circle of light much above and below that.
I'm not sure why, but I suspect alignment issues between the unit
itself and the pinhole "lens". The laser emitter on these cheap(!! :-)
laser pointers is a rectangular SMT device and I would be willing to
bet that these are not exceptionally high quality, possibly emitting
more to the sides than the center. Seems that there are a number of
elements to be aligned: laser diode itself, built in collimating lens
and the pinhole lens.

Short of more sophisticated machining than what I have, once the
batteries go west, you start all over again with the alignment
process :-/.

instead they have a *teensy* little hole at the bottom
through which the laser diffuses. The result is a very, very, small
dot (about 0.1mm or less) - this is usually accurate enough to get
you to close within half of this, as you guage the intensity of the
beam as you jog over the edge of the work. Have a black marker handy
and mark the metal first and the dot is reflected less, and thus
appears much smaller.

That helps here too. I was using a piece of the black 600 grit wet and
dry stuff grit side up for that, for initial alignment stuff, it really
helps. Dykum and just a black marker help a lot too, as you noticed,
just don't cover up the scribed lines :-).

A contact tool may be better for milling, particularly CNC-milling,
as unlike the laser the width of the tool is known - and you could
hook the contact sensor to your CNC system, so the computer can
actually hunt for the edges and set coordinates for you.
But, for a lot of tasks, the laser is more than accurate enough, its
certainly very painless.

From what the one that inspired me site has to say, a couple people
using it were able to consistently(?) get a repeatability of 0.0004.
Not scientific by any means, but that would be more than good enough
for a lot of what I do.

And, the laser makes easy something which is not possible with a
touch-probe: setting the center cutting height of your lathe cutting
tool. Just pop the laser in the head/tailstock and align to the beam.
I really do wonder why I fussed around with that sort of thing for so
long before.. :)

Understand that :-)! I'm sure this is doable and probably even usable
as it sits but there is something there that I haven't nailed down yet
that would simplify this far more than what I am doing now.

While this has been fun, if I was getting minimum wage (less gov
bloodsucking) I would still have been ahead just purchasing one :-).
Still it has been educational and provided for some serious thought in
the matter which is always rewarding if not necessarily successful :).

Someone asked which one, I have found two of them so far, leaning more
toward the first if I decide to just purchase one:

(LMS has these).


Take care, Vikki (Still scratching head).
--
Victoria Welch, WV9K/7
"In these modern times, many men are wounded for not having weapons or
knowledge of their use." -- Achille Marozzo, 1536