rabbit laser useless machine

[Hannu Rinne]

Around last x-mas I purchased some lenses and mirrors from this Chinese company ( www.eclaser.cn ). Lenses are made of ZnSe, ZnSe PVD - $ 28,-/ piece and ZnSe CVD - $ 49,-/piece. Honestly saying I don't have any idea what's the difference between PVD / CVD , but I've tested both of those and seems to work great even I'm quite lazy to clean them... I don't know the prices in US, but these feels quite cheat ( of course have to add taxes & delivery, but still... ). Mirrors - Molybdenum and Silicon - was $ 19,-/piece.

- Hannu

[toni split]

hi guys,

focus was problem.most probably because I work almost only with glass,lens get to much dirt to quickly and probably it heated more because of that.
Last two months I work with lens from same company but with bigger focus and till now I didnt have any problem.
thank you one more time for your advices

[Dan Hintz]

Toni,

Glass is a very "clean" substrate, at least from the point of view of the lens. Whatever glass chips off will not adhere to your lens, so if you are seeing a lot of dirt build-up, it's not from the glass, it's from something else. Maybe you need to filter your air supply...

[toni split]

Dan,

air supply works very good.
Glass is not so clean like you say.
My main work are drinking glasses and when I put 100 pcs in machine to do work,little pieces (it looks like very fine powder )stays on lens and most probably it doesent let beam to go throw that or make double reflection I dont know but after I put 60 mm focus lens (old one was 41 mm)I dont see any dirt on lens and I can do my jobs without any problem.
Now is allmost three months that I work and without any problem.
With old lenses I couldnt do 5 - 10 jobs before lens broke.

[Dan Hintz]

You have air issues... I have cut maple plaques for an hour and a half straight without any noticeable buildup of smoke on the lens (and this was without air assist across the lens, just the dust collector running). Glass shards should not be sticking to your lens (and yes, there will be a fine dust created, but it should be sucked up by your dust collector).

[toni split]

Ok,thank you...

[Bill Cunningham]

I do from about 10 thousand (+-) glasses per year, and have been running the same lens for 7 years. Dans right, you do not have enough airflow through your machine to remove glass dust and particles. You don't need air assist for glass, but unless you have enough air flow 'through' the machine to your outdoor vent, the glass dust is going to build up, and eventually ruin something else besides your lens..

[Michael Kowalczyk]

Sorry to hear that you are experiencing problems.
First off Chinese machines are notorious for their lack of support. Any equipment that is made and supported by a company form any country that does not speak your native language will be hard to deal with. You exchange service for price when you purchase a Chinese manufactured laser.
Now to your problem.
Frank and Dan have given you some sage advice.
Are you only lasing glass? Wood and other products can and will cause crud to build up on the lens causing heat buildup.
Did you properly align the beam to dead center of all the mirrors and the lens? If not this could be your problem. It took me 4 hours to get my beam dead center. And it is time to adjust it again.
Also do you operate your machine in a high humidity area? Even the slightest of moisture on the lens will cause heat buildup and crack the lens.
Do you have air assist and is it working properly?
Reflection can cause some issues but the odds of a perfect reflection back to the lens seem small unless you are lasing the front side of a mirror.
What model machine do you have?

I ran my rabbit 10 hours a day for the last three days and 18 hours yesterday. Cutting and engraving Baltic birch.
Thanks for reminding me to clean my mirrors and lens today.
I hope you get your problems worked out.
Best regards
Jim J

Hey Jim,
Not to side track this post but 3 10 hour days and an 18 hour day of lasering Baltic birch. WOW!!!! That's a lot of birch. Glad you're keeping it busy. Are you building a house? Ornaments, tributes or ???

I now return you to your regularly scheduled post and ...

[toni split]

I do from about 10 thousand (+-) glasses per year, and have been running the same lens for 7 years. Dans right, you do not have enough airflow through your machine to remove glass dust and particles. You don't need air assist for glass, but unless you have enough air flow 'through' the machine to your outdoor vent, the glass dust is going to build up, and eventually ruin something else besides your lens..

But I use and airflow and air assist togheter all the time...
I dont know,so far for the last three months I work without any problem but now when you insisting on air problems if next time something happen with lens that will be first thing that I will maximize.
Thank you all for advices,it is nice to get help with this things...

[Dan Hintz]

Show us a clear picture of your lens after it has gone bad... don't clean it at all, just take a picture fresh out of the machine.

[James Jaragosky]

Hey Jim,
Not to side track this post but 3 10 hour days and an 18 hour day of lasering Baltic birch. WOW!!!! That's a lot of birch. Glad you're keeping it busy. Are you building a house? Ornaments, tributes or ???

I now return you to your regularly scheduled post and ...

I was doing a run for a internet business that sells dog related items. based out of Washington. This was the second order from them and it was much larger than the first. Full of Christmas themed stuff they designed.

[toni split]

dan unfortunally I didnt take pictures of dirty lenses but I have one that I pictured after it was broken so I will attach that picture.
Maybe in my workshop I have somewhere more old lenses that are not cleared If I find it I will post it.
first picture is soon before damage and second one is after

[Dan Hintz]

That is a seriously dirty lens... if you can see dirt with the naked eye, it needs to be cleaned. Continuing to use it at that point is begging for fatal damage.

[toni split]

It is not dirt,it is damaged...

[Dan Hintz]

Damage like that does not happen on multiple lenses unless you are doing something wrong, such as not keeping the lens clean, not ensuring proper airflow, etc. There's only so many ways I can say it, but the lens or machine is not your problem, something you are (not) doing is...

Is your air assist free of moisture?