View Full Version : Brainteaser

Chris DeGerolamo
08-30-2016, 4:53 PM

Any one have any clue on how to engrave a solid band about the circumference of the tool, location indicated by the (2) arrows?

Length of center "flat" section is approx. 5.75", end bends are approx 2.25".

I cannot use the rotary in any conceivable fashion that would not lead to the part rotating into the gantry.

The only solution I can figure (and one I cannot do) would be to use a rotary on a galvo laser with a focal length greater than the clearance needed in space to rotate the part.

Customer spec is that it must be lasered btw...

Braden Todd
08-30-2016, 5:00 PM
Can you add a 5" or longer lens for the job?

Gary Hair
08-30-2016, 5:29 PM
A galvo would make easy work of that Chris!

Kev Williams
08-30-2016, 5:32 PM
It's not as bad as you think, IF the drawing is reasonably to scale...

If the bottom graphic is true, then the upper graphic should be close- it's over 2" tall, but less than 3"-- ergo, it's very do-able with a 3" lens... :) (assuming your chuck centerline is above 2-1/4")

>edit< -- and actually, a 2" lens should do it, since the lens housing & head won't be anywhere near the far end, and assuming 2-1/4" above centerline, that won't hit the gantry.

My LS900 would have no problem with these...


Chris DeGerolamo
08-31-2016, 9:12 AM
Thanks all so far. I would be able purchase a 4" lens to eliminate conflict with the gantry.

My issue then would be relegated to fixturing the part on the rotary: Epilog's rotary has no chuck mechanism, only drive wheels on which parts rest while turning. And then of course applying Cermark to the parts...

Joseph Shawa
09-07-2016, 3:21 AM
Maybe more trouble than it is worth but if you could temporarily mount your cutter head tube and lens horizontally just after the 2nd mirror by whatever means you might come up with (could be in a wood block resting on the table). Mount the target in a vertical position and spin on a turntable in front of the beam at the focal point. You could set your test beam to fire for the required time and power to get the result you want. Set at 45 RPM the math would work out 45/60 or 75ms per 1 rotation. You could defocus a bit to get a wider band.

Chris DeGerolamo
09-07-2016, 1:37 PM
Here's what I've come up with....this make make a bit more sense to those that have some experience with rim drive rotaries and Epilogs, but here it goes:

Afterthought short version: I'm modifying the rim rotary to a chuck rotary.

Long-winded and likely confusing version:
I will offset the drive wheel down to be in-line with the gantry by moving the entire rotary down [the distance from the center of the drive wheel to the x-axis]. Then a custom milled spacer similar to what Epilog provides (the piece with additional o-rings) will attach via thumbscrews. This spacer will accept the part from either of the bend ends and allow the part to be marked reliably. I'll need a 4" to get the needed clearance. The plate of sorts I'll use to move the drive wheel down will also raise the centerline of the drive wheel to give me clearance from the bottom of the table to the part while it rotates also.


Joseph Shawa
09-09-2016, 3:01 AM
Well, make sure to post a pic. : )

Chris DeGerolamo
09-09-2016, 11:46 AM
If we win the bid and don't have to put an NDA in place, I'll share for sure.