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James Jaragosky
03-04-2009, 2:54 PM
I have been tryng to use the laer to apply #'s on some clock faces I produced on my cnc machine.
Due to the varying thickness of the carving; I am having focus issues. Would getting a different lens for my laser mitigate this issue?
Here is a link to photos of my problem. sorry but SMC would not let me upload the photos twice.

http://sawmillcreek.org/showthread.php?p=1071675#post1071675
Thanks for the help.
Jim J.

Gary Hair
03-04-2009, 3:02 PM
A longer lens would help, a 4" vs a 2", for example. How about leaving a small area uncarved for the numbers? You could even use the cnc to carve the letters, vcarve would do quite well with that.

Gary

Frank Corker
03-04-2009, 9:48 PM
You look so much younger than that old guy who's picture you used to use!

Joe Pelonio
03-04-2009, 10:28 PM
You still wouldn't be too happy with the results from a longer focus lens, That's the problem with lasers, they have to be in focus to do a nice job.
I like the suggestion of leaving small flat areas for each number, but also,
you might consider cutting the numbers from 1/8" wood, and mounting them into holes with dowels so they sort of hover on the same level plane.

James Jaragosky
03-04-2009, 10:40 PM
You still wouldn't be too happy with the results from a longer focus lens, That's the problem with lasers, they have to be in focus to do a nice job.
I like the suggestion of leaving small flat areas for each number, but also,
you might consider cutting the numbers from 1/8" wood, and mounting them into holes with dowels so they sort of hover on the same level plane.

That would work. but the extra machining and labor cost would make this project unrealistic. I will keep searching for my niche.
Thanks
Jim J.

Scott Shepherd
03-05-2009, 7:40 AM
James, nice looking work! Can I ask why you're bothering with trying to do the letters on the laser instead of just adding them to the file with your cutting them? Wouldn't it be easier to put the numbers into the shape and let it mill those as well?

James Jaragosky
03-05-2009, 10:29 AM
James, nice looking work! Can I ask why you're bothering with trying to do the letters on the laser instead of just adding them to the file with your cutting them? Wouldn't it be easier to put the numbers into the shape and let it mill those as well?
Scott; those projects did not start out to be clocks,they were test pieces while learning my CnC router and related software.
I wanted to do something useful with them and decided on a clock face.
Because the dark laser numbers make excellent contrast to the natural wood background, I may incorporate the laser into future projects. I just need to plan ahead and not do it as an afterthought.

Dave Johnson29
03-05-2009, 10:45 AM
they were test pieces while learning my CnC router and related software.


James,

Adding to the suggestion of raised flat pads engraved as numbers, what about doing that then rastering those flat pad tops?

Since the router is operating from a drawing the pads will be positioned very accurately and thus should be easy to locate for alignment for the laser. That would give you the contrast on the numbers you seek.

I would make jigs (1 for router, 1 for laser) that locates the clock face on the center hole and also has an indexing hole somewhere on the blank for angular location. Something that can later be trimmed off or made a feature.

Brian Robison
03-05-2009, 11:26 AM
Non of my business but, have you thought about not having all the numbers? Maybe something for the 12,3,6 and 9? Looks to busy to me. IMHO sometimes less is more.

James Jaragosky
03-05-2009, 2:19 PM
Non of my business but, have you thought about not having all the numbers? Maybe something for the 12,3,6 and 9? Looks to busy to me. IMHO sometimes less is more.
Actually my first design was a 12-3-6-9; but SOMBO didn't like it.
I think that in the future both styles will be coming off the production line.




Adding to the suggestion of raised flat pads engraved as numbers, what about doing that then rastering those flat pad tops?

Since the router is operating from a drawing the pads will be positioned very accurately and thus should be easy to locate for alignment for the laser. That would give you the contrast on the numbers you seek.

I would make jigs (1 for router, 1 for laser) that locates the clock face on the center hole and also has an indexing hole somewhere on the blank for angular location. Something that can later be trimmed off or made a feature.

Dave :
I was thinking along these lines myself. I just need to plan the whole project with the laser in mind from step one.