Full Version: Uh oh, laser overheat trouble
From: Rodney Gold (RODNEY_GOLD) [#6]
6 Jun 2005
To: Nick (KOZASNJZ) [#4] 7 Jun 2005
Hiya
We often have or had thermal overloads with both Synrad and Coherents. I have never seen a reset switch on either , but Im not at all familiar with your machine. Mostly the sources we have used required some time to cool down and then reset themselves.
An 80w laser is pretty much on the edge of air cooled capacity . you will find that as you get to the 100 w mark , sources tend to be water cooled so environemntal conditions like a hot day with high humidity can cause this.
One of the reasons the sources overheat is that the heatsink fins on the source get clogged up with dust , a paintbrush and a can of air (stuff photographers use) can be used to clean these as well as cleaning the fan blades and air holes etc. Leaving the cover open is a bad strategy , at least with our machines it is , as the whole enclosure is designed to flow air the best way over the source and closing it and using the supplied fans works better. We have fitted extra fans to our lasers as well as beefing up the power supply to the lasers and no longer have overheating problems , we also use an aircon in our laser room.
Sudden and unexpected thermal overloads on our machines have often been a precursor to RF board failure or source failure. I would check that the machine isnt down on power. We use a 3mm piece of acrylic to check ours periodically, we know it will cut at x power and z speed , if we have to reduce the speed or up power - we know we have a problem and depending on how much we have to up the effective power , whether its alignment or the source itself.