Pocket engraving question

[Robert L Stewart]

What lens will I need to engrave into a pocket that is 2 3/4" deep. I will be engraving anodized alum. I have a Epilog mini
with a 1.5 " lens. From what I understand the lens is held in with epoxy so they are not that easy to swap out. I do not
think it's practical to swap lenses whenever I change jobs.

Any thoughts on how to do this? This will be an on going project so I may need another engraver.

[Scott Shepherd]

2 3/4" deep into a pocket is going to take a 4" lens. Maybe a 3" if they have such an animal. I haven't seen the mini in a long time, but normally you can swap out the lens. It comes glued into it's own mount. You'd have see if Epilog offers a 3" or 4" for the mini. I know some manufacturers only offer limited choices for certain models.

Or a Galvo system. A galvo system would get you 12" or more of clearance.

[John Noell]

On my mini it is not glued in. That said, I bought a second mount from Epilog and put in a 4" lens. (I do a lot of uneven curved surfaces engraving and the 4" makes it possible.) It is a lot faster and easier to change the mount (just four small bolts and the alignment is fixed so its hard to mess up) than taking the mount apart and replacing the lens. For that matter, you can pretty easily find about any focal length you want, 2.5", 3", or 4".

[Robert L Stewart]

Thank you Scott and John for the good news. Will give Epilog a call.

It seems that a 3" lens and mount may do the job. Wondering about the engraving quality with a 3" lens. I will be doing text on this project, a 3/8" tall font.

[Gary Hair]

Thank you Scott and John for the good news. Will give Epilog a call.

It seems that a 3" lens and mount may do the job. Wondering about the engraving quality with a 3" lens. I will be doing text on this project, a 3/8" tall font.

If it's a big enough job it would certainly justify a galvo fiber or co2. A 3" lens should work fine with 3/8" text, but it won't be even remotely close as sharp as you could get with a galvo.

[Kev Williams]

FWIW, I get better-than-acceptable results from $20 e-bay/Chinese lenses, and they come in several focal lengths and diameters.

Right now I'm using one, a 4", in my LS900 to engrave coconut cups. My LS900 lens and holder requires a special snap-ring tool to change out the lens, which I don't have, so I just McGuiver'd one of my Triumph lens holders to work- which was basically wrapping some tape around the bottom of the lens tube so it would fit - upside down - in the LS900 lens clamp. Works like a charm!

original lens and holder (bottom of the auto-focus plunger is removed)




My 4" 'coconut conversion' (with homemade extended auto-focus plunger)




--speaking of auto-focus plungers, do you have one, and if so, does it extend beyond the lens like mine does? If yes and yes, you may have to remove it...?

[Robert L Stewart]

If it's a big enough job it would certainly justify a galvo fiber or co2. A 3" lens should work fine with 3/8" text, but it won't be even remotely close as sharp as you could get with a galvo.

Thanks Gary, I thought that would be the case. Would love to have a
fiber to do metal jobs.

[Robert L Stewart]

FWIW, I get better-than-acceptable results from $20 e-bay/Chinese lenses, and they come in several focal lengths and diameters.

Right now I'm using one, a 4", in my LS900 to engrave coconut cups. My LS900 lens and holder requires a special snap-ring tool to change out the lens, which I don't have, so I just McGuiver'd one of my Triumph lens holders to work- which was basically wrapping some tape around the bottom of the lens tube so it would fit - upside down - in the LS900 lens clamp. Works like a charm!

original lens and holder (bottom of the auto-focus plunger is removed)




My 4" 'coconut conversion' (with homemade extended auto-focus plunger)




--speaking of auto-focus plungers, do you have one, and if so, does it extend beyond the lens like mine does? If yes and yes, you may have to remove it...?

Thank Kev, I removed the auto focus per Chuck Stones recommendation in the first week of using my machine. Although every once in
a while I forget to focus. Nice set up. Looks like that job requires some real experience. Thanks for posting the images.

[Robert L Stewart]

For those interested, I was quoted $300.00 (from Epilog) for a 4" lens assemble that is a 2 bolt change out. It will require alignment the first time installed.
After that it's a quick change to swap with my 1.5" lens. Was hoping for a 3" but they only offer the 1.5", 2" and 4".

Thanks again Scott and John.