View Full Version : smaller than usual fiber lens, want to buy more, but--

Kev Williams
02-11-2019, 5:54 PM
My 2nd ebay machine finally came today- 2 weeks late due to inventory oops, but all's well-

Both these machines are from the same builder, new one is a cabinet model version. One big difference between the two however, is the lenses, first one came with a 150x150, the new one came with a 220x220. I have a 220 for my Triumph fiber, really comes in handy for the bigger stuff I do, and so will this new 220. However, my normal needs call for a 150 or less for the power density and engraving detail, both of which suffer a bit with a 220 lens.

But the big issue is, I can't find a similar lens ANYwhere, and I can't buy what I can't find!

This is the 150 lens and the scanhead--
403312 403313 403314
--now, I've seen this 'brand' of scanhead around, with the weird 'E' logo but every one I've seen has the bigger hole that accepts a collar, which accepts the typical 'big' F-theta lens. These lenses are only 2-9/16" in diameter, and threads directly to a much smaller hole in the scanhead, with no collar.

I have nothing bad to say about their performance, the only anomaly I've noticed is the actual focus distance is substantially longer than the same mm bigger lens; my big 220 lens focuses at 14.75", this smaller lens focuses at around 16"! The 150 is about an inch farther than my bigger 150. I'm assuming the smaller lens doesn't have the same amount of usable working radius. That should mean less power density for the same mm-size lens, but I've noticed just opposite.

ANY way, I don't know what these lenses are called, no brand name on them, "F-Theta" is not on them, just the basic lens info. Each lens has a part number, but searching with those numbers doesn't help either. I've found a couple of similar lenses in photos, but not on the websites they came from. I can find scads of the bigger versions--?

thanks :)

Gary Hair
02-11-2019, 9:56 PM
Kev - I have a virtually brand-new 150 at the shop that I bought with my first machine and only used a couple of time to test settings. I have no use for it so if it will work for you I'm sure we can work out a deal. I'll check it tomorrow and let you know what it is.

Gary Hair
02-12-2019, 9:01 AM
I guess mine is the bigger one as well. The threaded part is about 85mm/3-3/8" diameter. On a brighter note, if anyone needs a 150 lens I have one!

Kev Williams
02-12-2019, 6:24 PM
I figured yours would be large-ish.

John Lifer
02-12-2019, 6:33 PM
alibaba https://www.alibaba.com/product-detail/F-theta-lens-for-fiber-laser_60678289816.html?spm=a2700.7724857.normalLis t.228.1ab75affn2tjI0

This link shows several 39mm diameter threaded lens. Might be what you are looking for