build your own laser set up

[hughie]

I have often thought of building my own laser setup for deep hollowing etc and found this sites

http://secure.oatleyelectronics.com//index.php?cPath=27





(http://www.mwave.com.au/productdetail.asp?SKU=49080032)

[Paul39]

I wonder if one of the pen sized ones in a mount would work?

http://www.amazon.com/pointer-laser-pointers/b?ie=UTF8&node=229183

Or disassembled and the emitter and lens mounted separately from the power supply.

At the price of the cheaper ones, not much lost if it doesn't work.


(http://www.amazon.com/pointer-laser-pointers/b?ie=UTF8&node=229183)

[NeilS]

Yeah, it's on my long 'to-do' list. It usually moves up the list as I'm getting to the bottom of my next hollow form, but then slips back down the list as I move on to other things...:U

Next time!

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[hughie]

Or disassembled and the emitter and lens mounted separately from the power supply.
At the price of the cheaper ones, not much lost if it doesn't work.Paul,
I looked at that but they just don't have the power to produce a good spot. Ok if you turn in the dark tho' :U. Over your way they are even cheaper than here in Oz.
We have some tight restrictions governing size and importation. Due to some thoughtless morons shining more powerful ones at commercial aircraft. Blinding flight crew and nearly causing a major disaster. dopey ......s
So now if you buy a 5mw+ laser your name and address will retained should law and enforcement authorities require it in the event of disaster etc. Importation of similar lasers are by registered importers etc etc.


(http://www.amazon.com/pointer-laser-pointers/b?ie=UTF8&node=229183)

[wheelinround]

:2tsup: good find Hughie

[NeilS]

I looked at that but they just don't have the power to produce a good spot.

(http://www.amazon.com/pointer-laser-pointers/b?ie=UTF8&node=229183)

What power do you reckon is needed, Hughie?

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[hughie]

What power do you reckon is needed, Hughie?

not really sure but found this, a laser forum

A Guide To Buying Your First Green Laser - Laser Pointer Forums - Discuss Lasers & Laser Pointers (http://laserpointerforums.com/f45/guide-buying-your-first-green-laser-30608.html)

[NeilS]

Thanks for the forum link Hughie. Had a brief read. My initial conclusion is that it is only the dot, not the beam, that needs to be seen in daylight, and we are only talking about a projection distance of a few inches, not metres. So a lower wattage might do it. Might just try a few pointer options out in the torch shop in town to see how well the different options work before I take the plunge.

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[hughie]

Already had a go at a few pointers with little success. Also had a look over Erns set up when I was there. He suffered a similar problem the dot intensity was lacking especially when in a well light situation. I believe the green is better than the red, some to do with the colour etc.

Anyway will have a go at the 5mw ones when they arrive and post my findings

[Allen Neighbors]

Thanks for the links, Hughie. I built my own hollowing rig, and just bought a laser pointer pen from Radio Shack to use for the dot. It's red, and a little bit larger than I'd like, but it works okay for me. I didn't have the guts to try to build my own light system, due to my inability to understand the schematics I've seen.
I've also seen some ideas on how to reduce the size of the dot, but so far it hasn't been that important to me. I have no idea what the power is, in the pen I have.

[NeilS]

Already had a go at a few pointers with little success. Also had a look over Erns set up when I was there. He suffered a similar problem the dot intensity was lacking especially when in a well light situation. I believe the green is better than the red, some to do with the colour etc.

Anyway will have a go at the 5mw ones when they arrive and post my findings

OK, you've saved me a trip to town...:U

Yes, read green is superior to red.

Think I'll wait your report.

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[hughie]

Thanks for the links, Hughie. I built my own hollowing rig, and just bought a laser pointer pen from Radio Shack to use for the dot. It's red, and a little bit larger than I'd like, but it works okay for me. I didn't have the guts to try to build my own light system, due to my inability to understand the schematics I've seen.
I've also seen some ideas on how to reduce the size of the dot, but so far it hasn't been that important to me. I have no idea what the power is, in the pen I have.

Hi Allen,

Good to see on the forum again. I suspect your pen pointers have more power than ours. We have had some restrictions put on laser pointers due some morons pointing them at planes. I think our max is 1mw for all pointers and they are to be red as well.

[Frank&Earnest]

Yes Hughie, you are right. What do you want to achieve, exactly? Eg a light source visible through X mm of wood of density Y? Self standing or attacheable to the hollowing tool? In my ignorance, I would have thought that the light source does not necessarily have to be a laser, given that the focus is so close, if the size is practical.

[hughie]

F&E I intend to build something along the lines of this:

http://www.woodturningonline.com/Turning/Turning_content/Turning%20Depth%20Finder.pdf

Basically use the laser to determine the thickness of any hollow vessel I am turning as I go along.

[TTIT]

Just jumping on here to see if the green laser works any better than the little red one (http://www.ttit.id.au/gadgets/hollower/16.JPG)I put on my hollowing rig (http://www.ttit.id.au/gadgets/hollower.htm) - which I don't have any problems with (other than the grand-kids trying to snavel it all the time :~ ).

[hughie]

Vern, I think its all to with intensity of the beam and green has it over red. I have ordered 5mw red, 5mw as its about as low as you want to go...so I am told and its low powered enough not have a effect on the old eye ball. Over this and you have to be very careful where its pointed etc.
The good about Oatley Electronics is that the price of all the lasers is quite reasonable. So I might up grade later, will see how I go. Still building the darn shed :C everything is kinda getting in the way, must be Murphy's Law at work:U

[Frank&Earnest]

Hughie, thanks for the link. I appreciate I risk looking stupid here :D but I am missing the point of that gadget. If I understand correctly, all the laser does is to point from the outside where the end of the probe touches the end of the vessel, which could be achieved with much simpler mechanical means. I thought that the point was to shine the light through the wall to assess its thickness. Where am I going wrong? :?

[RETIRED]

Read Verns link on hollowing jig. Right down the bottom.

[NeilS]

the little red one I put on my hollowing rig (http://www.ttit.id.au/gadgets/hollower.htm) - which I don't have any problems with (other than the grand-kids trying to snavel it all the time http://cdn.woodworkforums.com/images/smilies/anoyd.gif ).

What watts is your little red one Vern?

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[NeilS]

Read Verns link on hollowing jig. Right down the bottom.

Did read the bit right at the top....:rolleyes:

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[TTIT]

What watts is your little red one Vern?

.....No idea :B. I'll let you know when I get home and have a look.

[Frank&Earnest]

Thanks . Vern's jig appears to me much more useful than the other one because it is attached to the hollowing tool, the other is self standing and can only be applied after the cut is done. Having now established that with these jigs the thickness of the wall is estimated by looking at the shape and position of the dot on the outside wall, in principle I would still prefer a mechanical solution instead of an optical one, possibly for an attached jig, definitely for a self standing one. In practice, I can't tell until I have tried building one, and if I try one it will look a lot like Vern's. :2tsup:

[TTIT]

What watts is your little red one Vern?

.....Still no idea :C There's no markings on it and I've "misplaced" the paperwork that came with it :;


Thanks . Vern's jig appears to me much more useful than the other one because it is attached to the hollowing tool, the other is self standing and can only be applied after the cut is done. Having now established that with these jigs the thickness of the wall is estimated by looking at the shape and position of the dot on the outside wall, in principle I would still prefer a mechanical solution instead of an optical one, possibly for an attached jig, definitely for a self standing one. In practice, I can't tell until I have tried building one, and if I try one it will look a lot like Vern's. :2tsup:You'll find that the problem with any mechanical solution is that they range from difficult to downright dangerous to use while the work is rotating which is the only time I use the laser. Once the lathe is stopped, I use my big calipers (http://www.ttit.id.au/gadgets/gadgets.htm#Calipers) for an accurate measurement.

[TTIT]

Vern, I think its all to with intensity of the beam and green has it over red. I have ordered 5mw red, ......................My main interest in the green laser is that I have done a couple of pieces where the colour of the timber seemed to camouflage the red laser considerably so it would be great to have a choice - now we'll have to find another guinea-pig :U

[NeilS]

Still no idea :C There's no markings on it and I've "misplaced" the paperwork that came with it :;


OK, Vern, thanks for looking.

PS - love those big calipers...:2tsup:

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[Frank&Earnest]

You'll find that the problem with any mechanical solution is that they range from difficult to downright dangerous to use while the work is rotating which is the only time I use the laser. Once the lathe is stopped, I use my big calipers (http://www.ttit.id.au/gadgets/gadgets.htm#Calipers) for an accurate measurement.

Thanks Vern, there is obviously some aspect that I am not able to visualise at the moment, hence my proviso that the practical problems will come out in the making. If you could elaborate on the reason(s) for the difficulty/danger or point to existing solutions that you found unsatisfactory, you could save me some laundry expenses...:)

[RETIRED]

It is too easy to let the outside measuring pointer (arm, guide, call it what you will) run into a thicker bit and twist the boring bar out of your grip.

This results in bad language, ruined whatever, bent tools, ruined tools, a stain on the floor and undies and personal injury.

If the pointer is too weak it will not hold a true measurement as it will bend making a measurement useless.

If you don't have a laser, STOP the lathe to measure all internal measurements.

[Frank&Earnest]

Thanks , I think I understand the problem now. If the pointer is set on a predetermined thickness it might impede the advance of the cutter with the consequences described in picturesque detail. Did I get it?

[RETIRED]

Yep.:)

[Frank&Earnest]

Wonderful! This seems to mean that what I have in mind has not been tried yet. Stay tuned! :2tsup::2tsup::2tsup:

(of course I am honest, will say it if it bombs out...laundry included :D)

[hughie]

F&E, I came up with device that could mechanically measure wall thickness on the run and translate it in to MM etc. But at the end of the day it has inherent problems attached to it as outlined by .

What is far better is to do the measurement without:


interfering with the process
occurs continually
not intrusive ie physically need to be in contact
not effected by waste material
accurate
light weight
simple in operation
no moving parts
effected by bounce or mechanical wear

The laser meets all these considerations with ease

[Frank&Earnest]

Thanks Hughie. If it is not a trade secret (and it would not be, if you discarded it! :) ) what principle did you use to measure wall thickness? It could save me reinventing another wheel.

As far as accuracy is concerned, wouldn't you say that, all other things being equal, your method was more accurate than the laser pointer? There is another consideration here, which I do not know how it affects the decision to use a device of some sort for this purpose. It appears to me that, in practical terms, the quality of the internal wall is very important when the opening of the vessel is large enough to allow touching it. Which means that checking by touch is also the easiest and best thing. If the opening is small, accuracy needs to be only sufficient to avoid poking through the wall. So, unless one wants to win a woodturning contest, the accuracy of the laser could be sufficient. Makes sense?

[hughie]

F&E I have it some where around in box :C it'll come to light eventually. Essentially it was a couple of curved arms . The outer being fixed and the inner move able, the inner had a 10mm ball fixed to it so it would ride over the lumps and bumps and of course sprung loaded.
The move able arm came in contact to another sprung loaded arm of a much shorter length. Which acted as a pointer to which I applied a small scale calibrated in mm.

Some of the problems with this design:



it must be in contact with the job, see Robbos list
It will bounce around and is not so user friendly
has limited usage if you turn a wide range of hollow vessels.
mine was independent of the tool. So it required the turner to stop and measure.


Laser accuracy should be good, much of it is operator dependant. But like any thing else its a skill set to learn.

Both devices can produce a smooth finish internally if the turner is capable. My preference is to the laser as its not in contact with the surface and measures continually as you turn.
No doubt you can have a mechanical device the measures on the run. But we then introduce another rigid arm into the process making contact with the vessel. This could well be a recipe for disaster.

But at the end of the day its what we are comfortable with. For instance I rarely use a face plate, preferring instead to hold my bowls etc by screw chuck and tailstock. Too some, this is fool hardy at best and down right dangerous at worst.

[Frank&Earnest]

Thanks Hughie, much appreciated. We have another thing in common, besides loving making our own gadgets: I do not like the faceplate either. :2tsup: