Lenses from China?

[Allan Longson]

We are looking at getting a back up lens for our universal laser. Can anyone recommend a company they have purchased lenses from in china?

[George M. Perzel]

Hi Allen;
I bought a Chinese laser which will be delivered tomorrw-also bought new lenses from them for my GCC Laserpro-$40 each for the "imported-Germany?) lenses. Will post results when I get a chance to plug them in the laserpro.
Bought from Shenhui.
Best Regards,
George
Laserarts

[Craig Matheny]

http://www.laserresearch.net/index.asp This is a USA company call them and you get a lens for about 150.00 I have used them and no issues my two prior lenses from Singapore and 6 months marked

[Mike Null]

I suppose I should buy a back up lens but in 14 years of pretty much full time use with two different lasers I have never needed to replace a lens.

I must be doing something wrong.

[Allan Longson]

Sadly the lens in our universal machine has lost a couple of specks of coating smack in the middle the lens and the power is down considerably. We managed to source one locally by pure luck (out of a new machine) but having a machine down for a while is not something we want to repeat hence the thought of a back up.

[Rodne Gold]

Mike , you what they called a "sofistikated" user , you can do and are religious about regular cleaning , maintenance and small repairs... :)
We pretty rough and ready with our lenses due to my staff operating the machines and they none too gentle, but I have cheap backup ones that work real well ($30 - I didn't buy the "imported ones" like george did)
I have found this : Pressurising the lens box with air assist has been our biggest contaminant of lenses , whether it be water/oil splatter from a failed/full trap or other stuff like creating some sort of suck back vortex in the nozzle assmbley , once we route air assist outside the lens box and pointing via a small nozzle slightly obliquley at the cut point , no more lens issues and better still , even less smoke/melt damage. The simplest solution seems to work best for me across all my laser platforms and models. YMMV

[Mike Null]

Rodney

I found early on that air assist does exactly what you say. As a result I never use it for rastering but always use it for vectoring. Since most of my work is in plastic and wood, both fairly dirty substrates contaminants can build up fast. If I'm running wood all day I may clean my lens hourly. Not cleaning results in degradation of the engraving and may result in lens damage.

[Allan Longson]

Hi Rodney - we are in the process of making an air bypass of the lens box as we found the same problems that you did (we are relatively new to the art of laser engraving). If I may ask did you get your lenses from shensui?

[Rodne Gold]

Yeh, I got them from Shenui, check out the thread "lasers , do you get what you pay for" , i posted the invoice including lens prices. Heres's a pic of my "high teck" lens bypass
Mike , we clean lenses maybe once a day - As you know , I use air assist on everything , the box pypass was cos the air assit supplied was coaxial with the beam and actually was sort of spreading any melt/smoke/resing etc coaxially round the point of vaporisation , will try some stuff without air assist as you do.