Melted air connection
Cracked Lens
Replacement scavenged from wide lens
User turned down air assist to nearly closed on Donner, our new laser.
User forgot to return it to fully open.
Another user - unaware of the problem - attempted to cut 1/8" plywood using perfectly normal settings.
Plywood caught fire.
Bad.
That Donner is back in operation…well, folks…that is due 100% to the efforts of @PearceDunlap.
People, I’m not even Laser Chair yet.
@merissa is checking the cameras.
The User-Who-Properly-Reported-The-Fire-Problem was not the first person to experience a fire.
At least one person extinguished a fire and left the building.
Public Service Announcement:
If something breaks/catches fire, post a sign that the laser is down and always tell us immediately. Use the Issue/Request category on Talk. We won’t yell…on the contrary, we will be grateful.
The fires were not operator error on the part of the current users. They couldn’t have known the air assist was left off by a previous user.
Hey @mblatz, I noticed you were on Donner most of the morning. Did you adjust the air or notice it being on/off? There were a few others on the laser today too before the report came in, but I don’t recognize them, so I just get to pick on you 
Eek, sorry! I guess I just thought I knew what you looked like 
@David_A_Tucker what about you… were you on Donner this morning and did you notice how the air assist was functioning?
Is there ever a valid reason to turn down the air-assist?
Possible reasons are cutting paper or fabric that won’t stay in place with full air assist. Still not great for the optics, but not nearly as bad as later cutting wood with minimal or no air assist. But if you do have reason to turn it down, you really need to set it back to normal after you are done.
I don’t know which one is Donner. I was on the laser cutter unit closest to the metal shop.
I noticed the air blowing the vaporized acrylic away, leaving a bit of a residue trail in the direction of the air flow to the vent. That didn’t seem abnormal to me.
The first time I tried to laser something, the blue painter tape caught fire, so quickly put it out and then peeled off the blue tape, which solved that problem. When cutting something last Friday on the middle laser unit, I was able to use blue painter’s tape without incident, so it seemed a bit odd to me. I just figured that someone has been using different settings that I inherited through the cutting software from some local PC setting.
What’s the damage? The machine worked fine after that for me, but I left around 11:00 a.m.
DT
How does one check the setting on the air assist? I feel like I’ll want to check that regularly before using the lasers now.
Thanks for the info. I’m realize you’re just clarifying and not defending here.
I cut lots of fabric and paper on those lasers, and frequently very small pieces. Rather than diddle with the air assist, I leave small tabs in my design and put weights around the perimeter. Sometimes I have to shift the weights around during the cut, but it’s easy enough to do.
Was this air assist thing covered in laser basics? I believe this is the first I am hearing of it. I just searched the wiki and see no mention of it. How would a normal person know anything at all about the air assist and how to turn it off or on?
Lets be careful in stating that all blame for damages are on turning the air assist down. Yes, the lowered air pressure may have allowed certain materials to burn easier than with full air pressure. But, the damage to the mirror is more likely due to the mirror being used after being coated buy dust and or smoke from cuts and or burning in the machine. Not so much the lower pressure air. Air pressure is surely part of the issue, but if it had been corrected or had others that burned materials on the machine noted it, the mirror damage probably wouldn’t of happened.
There are many ways to use the machine with low or to nearly no air pressure without harming the optics or the machine.
I would suggest that this is a moment to learn from. Once you find the member that turned down the pressure and didn’t return it to normal setting, give them a light reprimand. Then add to the training materials, a discussion of the air pressure setting on the machine.
I know this won’t fix all problems, but improved training brings up the average knowledge of the group. So when you have the member that took training 2, 3, or 4 years ago asking questions, those around them that help and took training more recently or are advanced users of the laser are better prepared to look for more possible issues.
That all said, I’m not saying the laser training or those that train are bad. This is just an opportunity to learn and grow.
to quote the machine shop motto: “this is why we can’t have nice things”.
To quote Dennis Leary: “Life sucks get a helmet.”
From one curmudgeon to another.
I didn’t intend to state that all blame for damages was due to turning the air assist down. I only intended to point out that there are workarounds that don’t require turning down the air assist.
I’m reluctantly jumping into this conversation… but here’s my 2cents, and worth exactly what you paid for it.
[Facts]
There is plenty of information on the internet that anyone can look up about using Air Assist on a Laser cutter. There are very valid reasons to turn it up or down, depending on the material being cut in order to get optimum results. ThunderLaser has YouTube videos covering the subject.
There is no mention of air assist in DMS laser training.
If only a few people know about air assist, and everyone else doesn’t understand what it does and why/when you need to make sure it is on, damage to the machine can happen. Especially if the previous user leaves it off and the next user doesn’t know to check it.
[my opinion]
This is now something we’ve seen first hand and this should prompt us to update training appropriately and educate existing laser users. We can post new information on the machine to tell people who haven’t recently received training, those that took training but weren’t paying attention, and those that were in training, learned it, but haven’t used the machine for several months and need a reminder.
This incident shouldn’t be a witch hunt, and it shouldn’t result in altering the machine so that it doesn’t work as well for certain materials and produces sub-optimal results. This is a fantastic opportunity to show that we can learn, educate, and improve for the benefit of everyone involved.
All 600 of them?
There are compromises to be made when dealing with shared resources.
The woodshop does not allow for metals to be cut in the woodshop at all, even though a number of the machines are fully capable. Likewise, I understand that certain ceramics are really never likely to be fired at DMS, even though we may technically have the ability to do so, because of inefficiencies in scheduling a custom firing for a single piece. Our large vinyl cutter has the capability to do cuts on things other than vinyl, but we have essentially limited it to vinyl stickers only, due to the fact that it would take some advanced changes to make it do those other cuts, and we want it to generally be a ‘walk in and use it’ machine.
It may not produce optimal results for everyone’s use case, but there are LOTS of commercial options available for edge use cases.
Yep. Need more rules. ALWAYS more rules. That’ll fix it.
No.
Volunteers fix things.
Customers don’t like rules.
Which are you?
I look at this as similar to someone who might need to cut a 5% bevel on the table saw. If you change it, make sure to change it back once you are done, lest the next guy/gal to use the tool might not notice your exceptional tweak to the tool setting.
Similar to if one were to change the drill press RPM or move the table off-square.
Same as if one were to replace the tablesaw blade with a dado blade set.
Same as if one were to replace the standard sewing needle on the leather machine to a ball-point needle for sewing heavy knits.
Same as if one were to change the centering on the laser from upper left to lower right (or any other setting).
There are many tools at the 'space which are used in a “standard” way 90%+ of the time. If you have a good reason for using the tool outside of that standard config, OK, but please leave it reset back to the “standard” way once done.
In the spirit of being excellent to each other, please don’t expect others to have to recognize your exceptional use of the tools - reset them.
