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Gumby
9th May 2007, 11:35 PM
Never afraid to ask a dumb question, but I'm still confused as to how that laser guide works when hollowing out on a lathe.

Stu's Ball video was great but trying to work out that laser is beyond me.

Can anybody put me out of my misery ? :(

(PS, I don't want to ask Stu. I'd feel a bit of an idiot. Better to ask here where i hope he won't notice)

DJ’s Timber
9th May 2007, 11:43 PM
Dumb ??? wouldn't worry you at all eh Gumby.

The idea with the laser is to have it pointed so that it is say 5mm from the cutting tip which is the thickness of the finish object for example.

As long as the laser is showing on the timber you know it's still more than 5mm thick, once the spot falls off the side off the vessel you have reached the 5mm thickness that you have set.

Clear enough for you or do you want me to draw it up for you as well

Gumby
9th May 2007, 11:52 PM
Clear enough for you or do you want me to draw it up for you as well

:):- yes please

later edit....

'click' ( that's the sound of the light going on) :)

thanks

Cliff Rogers
10th May 2007, 12:18 AM
...once the spot falls off the side off the vessel .....
I loose more spots that way..... :no:

PS. Gumby, if you are going to take up pen turning, you don't need a laser. :wink:

rodent
10th May 2007, 02:00 AM
WoodCentral Articles & Reviews 10.htm (http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=45741&stc=1&d=1178722517)
TRY this i dont know ifn i go t this right

Gumby
10th May 2007, 09:16 AM
I loose more spots that way..... :no:

PS. Gumby, if you are going to take up pen turning, you don't need a laser. :wink:

I'll take up pen turning the same day I wish somebody on here a happy birthday. :cool:

Stu in Tokyo
10th May 2007, 11:25 AM
Geez you guys, why did you go and tell Gumby how the laser worked, I was going to tell him it was special ninja voodoo magic :o :U

Oh well, the cat is out of the bag I guess..... :roll: :2tsup:

Works very well I must say, if I have some time I'll try to take a pic or even another video to bore you with, about the Laser rig.

Cheers!

Gumby
10th May 2007, 12:25 PM
WoodCentral Articles & Reviews 10.htm (http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=45741&stc=1&d=1178722517)
TRY this i dont know ifn i go t this right
Thanks for the link but the pics didn't come out :(


Geez you guys, why did you go and tell Gumby how the laser worked, I was going to tell him it was special ninja voodoo magic :o :U

Oh well, the cat is out of the bag I guess..... :roll: :2tsup:

Works very well I must say, if I have some time I'll try to take a pic or even another video to bore you with, about the Laser rig.

Cheers!

Doh ! :doh:

Skew ChiDAMN!!
10th May 2007, 06:15 PM
The idea with the laser is to have it pointed so that it is say 5mm from the cutting tip which is the thickness of the finish object for example.

I follow you so far...


As long as the laser is showing on the timber you know it's still more than 5mm thick, once the spot falls off the side off the vessel you have reached the 5mm thickness that you have set.

But you've lost me here. Showing on the timber? :? My plane polarized TEM mode, 10.6 µm, 100 GW laser pulsed at 200 ps pulse length doesn't exactly "show on the timber." Flash it into a plasma state, yes, but somehow I don't think this is what you mean? :p


WoodCentral Articles & Reviews 10.htm (http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=45741&stc=1&d=1178722517)
TRY this i dont know ifn i go t this right

Rod, you're really better off posting a link to the original URL instead of DLing it to your computer and then uploading that copy to these forums.

For one, it saves Neil a bit of server space and, for another, it won't break any links or code. :wink: Besides, I'd say that as often as not many of us would like to browse other pages on that site, which don't exist in your copy...

David L
10th May 2007, 06:28 PM
A video would be a good idea Stu some of us don't have lights as quick a Grumby's

Gumby
10th May 2007, 06:42 PM
But you've lost me here. Showing on the timber? :? My plane polarized TEM mode, 10.6 µm, 100 GW laser pulsed at 200 ps pulse length doesn't exactly "show on the timber." Flash it into a plasma state, yes, but somehow I don't think this is what you mean? :p


If you have a look at Stu's video, no laser showing means its still too thick. When the laser dot shows, it's at the thickness set.

'click' I think my light went out again.

Skew ChiDAMN!!
10th May 2007, 07:39 PM
If you have a look at Stu's video, no laser showing means its still too thick. When the laser dot shows, it's at the thickness set.

'click' I think my light went out again.

I gotta admit I haven't watched that vid... although I did watch the first. :)

But think of the laser as a plumb-bob that hanging from a fixture above the tip of the tool. It's offset to one side by the thickness you want the bowl. So long as the plumb bob is pointing at wood, the walls are too thick. As soon as it moves off the wood, BINGO!

In practice it's not that easy, but isn't that always the case?

Gumby
10th May 2007, 07:52 PM
click click click click...clickclick....click clck click.....

nope, nothing. I think the globe has blown. :(

Cliff Rogers
10th May 2007, 07:59 PM
Looks down barrel & pulls trigger one more time....

:fireworks:

"Well whaddya know.... one more buwwet. :D

joe greiner
10th May 2007, 10:31 PM
Here's a Q&D plan view through the wall of the turning. The laser dot is set at a constant distance from the cutter. Note there's a slight parallax problem as the cut goes off perpendicular from the lathe axis; usually doesn't matter, but at extreme "latitude" you can reset the laser dot location.

[BTW, it took me a while to get it, too. I first thought, "How the L does shining a light through the hole help you know the wall thickness?"]

Joe

Stu in Tokyo
11th May 2007, 03:06 AM
Sorry gents, I got busy today, but I finally got time to put these pics up.

Joe has it nailed! :2tsup:

But here are my pics of it.

45829
An overview of the set up.
I simulated a laser beam to make it easier to see

45830
So when the laser dot is touching the outside of the wood, the thickness of the hollow form wall is still more than the space between the laser dot and the cutter tip. Once the laser dot is no longer on the outside of the wood, that means the thickness of the HF wall is less than the distance between the laser dot and the cutter tip

45831
I use a piece of wood to see that the thickness is what I want, and that the dot is in the right spot in relation to the tip.

Hope that makes it clear!

Cheers!

Stu in Tokyo
11th May 2007, 05:26 AM
OK, one more pic for you.............

45832
......... This is a close up of a hole that developed in the side of the HF I'm doing now, the piece of bark inclusion came loose :doh:

I highlighted the cutter's edge with green, you can see the read laser dot as well.

Cheers!