Laser head / focal length / which and how and where to buy?

[bloq]

Hey,

i am only a few inches from finishing my buildlog laser . Yesterday i run into something i did not recognize before. I bought the laser head from lightobjekt which is recommended here. Unfortunately this does not have air assist and the suggested 3d printing was often discussed as no long time solution. Unfortunately i do not have access to a lathe so i went for google and bought a nice looking head from ali express (http://www.aliexpress.com/item/laser-cu ... 04216.html). Reeser from the forum (thank you!) explained me how the distance to the work piece is calculated and i recognized that a focal length of 50.8 as recommended here does not fit my head length. From the bottom to the middle of the lens it is 52,5 (why the hell do they make this? it could also have been shorter). So how did you solve that? I am not sure if a lens with a longer aperture would solve my problems without making new ones. Furthermore they are more expensive. The best solution would be a shorter bottom part of the head (nozzle?) which fits to the one from lightobject but i did not find anything on the internet.

Thank you very much for your ideas,

tm

[rsm5178]

I use this with a 50.8 lens.

http://www.lightobject.com/18mm-Laser-h ... -P701.aspx

You may need to take a dremel to the lens carriage plate like I did, but maybe it was my mirror mounts that caused the issue? Not sure since nobody else has said they had similar alignment issues.

Rich

[bloq]

Hey : )

i think i just bought the wrong air assist nozzle since it is too long for a 50,8mm lens. The carriage plate is fine but the distance from the lens to the end of the nozzle is too high. I think i should buy the one you suggested. Will this fit the carriage plate and the silver plate from the lightobject laser head which is suggested for the buildlog laser?
thanks!
tm

[rsm5178]

Yes. That is what I use.

Rich