laser Surveillance

[Martin Boekers]

After seeing Dean's dillema I got to thinking.
Yes, I do my best to keep an eye on my laser as much as possible but as Dean's experience shows serious damage can happen in minutes.

I my shop I have 2 lasers and heat presses they are in an adjacent room for temp & humidity control. I have my work area, then the store area.

Being a small shop it's hard to be everywhere at once.

I was wondering if any one has set up a web cam or security camera that is focused on the laser so you can keep an eye on it while working on files are dealing with customers?

Just a thought, maybe good insurance with a small investment.


Marty

[Scott Shepherd]

I have a webcam that I sit on the top of the glass on the lid, pointing in. I open a window with it and leave the small window open while working on the computer. If I need to do non computer work, I open it up larger, so I can see it across the room, and I always point myself in that direction when I'm working.

[AL Ursich]

I think at some point I will setup a Smoke Detector with the output relay that is hard wired into the Cover Switch and able to shut off the blower.

I plan to do the same with my CarveWright cover switch.

You would need to use a relay and power supply like a wall wart through the smoke detector. Use the Normally closed contacts on the relay so when the relay in the smoke detector activates it activates the external relay opening the normally closed contacts opening the Laser Door circuit.

AL

[David Fairfield]

I like that camera idea, my shop is divided with the laser behind a partition. I'd just be leery of getting into a habit of not really paying a lot of attention to the picture on the screen. It gets boring, and boring things are easily ignored.

I do simple tasks in the laser area when the machine is running. Stuff like packing small parcels. So I'm watching, but not wasting time either.

Anyway, I'm not turning my back on it when I'm doing acrylic, that stuff is just not stable.

Dave

[Kim Vellore]

I think at some point I will setup a Smoke Detector with the output relay that is hard wired into the Cover Switch and able to shut off the blower.


AL

Al,

A smoke detector will not be a good choice because it will be going off all the time. A heat detector will be too late and you may be able to save from additional damage outside the laser, what you need is a flame detector, Flame detectors are smart devices that actually look for flame radiation at different wave lengths and looks for the flame flickering pattern, compensated for ambient stray wavelength etc.... they are a little expensive too but one mounted on the top can cover your full shop. You can even hook up a co2 extinguishing system to it or a $5 halon extinguisher if you hook it up yourself just for the inside of the laser. Just read all instructions regarding Halon if you plan to use it.

Kim

[Dan Hintz]

Kim beat me to the punch... I'd go with an IR flame detector. If a smoke detector is not going off all of the time due to too much smoke in the area, it will be at the other end of the spectrum and not going off until it's too late (as your vacuum system pulls the smoke out right up to the point where the entire system goes up in flames).

If you do install a fire extinguisher system, use a Class C dry powder system (though not a standard home ABC system... that powder can be highly corrosive to electronics) or Halon. Don't use a CO2 system as those can make water condense on electronics.

[Keith Outten]

I have a camera mounted high on the back wall of my workshop that allows me to watch my CNC router from my upstairs shop office. It connects to the TV, it isn't a web cam.

This works well for my CNC router but it probably wouldn't work for a laser engraver. By the time I got to the laser if something happened the damage would be done. I expect you would have to be right on top of the machine in order to have any chance of preventing serious damage. FWIW the guy who owns LaserBits told me years ago that if you have a fire inside a laser engraver the machine will be ruined, the only thing you can do is prevent the fire from spreading outside of the cabinet.
.

[Randy Digby]

I noticed in Sam's the other day, a wireless camera / receiver set. The camera was about the size of a deck of cards and the receiver was about twice that size. Info stated that software was provided to view/record on PC if you like. Receiver can look at up to four cams. Price for a set was $149.00. They had a demo set out running and the pic was very good for the money. The cam and receiver both have batteries on-board and will operate for several hours on battery - normal operation is plugged-in power supply. Cam had decent mounting bracket.

[Keith Outten]

I wish I knew the answer to why acrylic tends to flame.

I have never seen a flame in my Epilog Legend 24 in the seven or eight years I have owned it and I have cut a truckload of acrylic.

In the shop at CNU we have a Xenetech laser engraver and I am fighting a flame problem that only seems to happen on the extreme right side of the table.

The Xenetech machine has a totally different air assist system then my Epilog. The Xenetech has a fixed bar that runs the length of the X axis, the Epilog has an air tube that is fixed over the lense and points directly over the cutting area.

The second condition that I am considering is dust collection. The dust collection on my Epilog is more powerful and more efficient than the one we use on the Xenetech.

One or both of these conditions has to be the reason that one machine never experiences a flame and the other does.
.

[Mike Null]

With my Trotec the flaming tends to be related to speed and power settings. The lower speed, higher power invariably will cause flaming.

I have taken to doing the cuts in more than one pass rather than take a chance with the flaming. Fortunately, my business doesn't require cutting a lot of thick acrylic.

[Dan Hintz]

Keith,

If the entire bar is pressurized and you only get flaming on the far right-hand side, is the bar pressurized from the left-hand side? If so, I'm willing to bet your pressure on the right side is significantly lower than on the left.

[Kim Vellore]

I have had fire when I was warming up the laser. I usually cut a square at 100% power, 1% speed and 5000DPI. I do that to avoid the start up no fire issues and once I put my acrylic part in to cut and remembered that I did not do my start up so I moved the part to the side and sent the square to be cut, unfortunately the moved acrylic part tip was inside the square and I saw orange light from the laser and I dont remember what I did but I managed to blow it out, there was not much damage there is slight heat damage on the top acrylic cover of the laser but I guess I was lucky... the next thing to burn up would have been the acrylic lid of the engraver. I am extra careful now with cutting acrylic.
Kim

[Marc Myer]

I've noticed the air nozzle on my Epilog is not aimed precisely at the focal point.
Is that intentional? I do get regular flaming with acrylic, even at 45 psi. Would like to figure how to reduce that.

I did notice the air assist path can become clogged. As a quick fix, I'll send air through it backwards.

[Dan Hintz]

I've noticed the air nozzle on my Epilog is not aimed precisely at the focal point.

Wouldn't this depend upon the lens you're using? A 2" lens will have the tube aimed at a different spot than, say, a 4" lens.

[Marc Myer]

You're right.
In my case, it's the stock 2" lens, and the air assist is as it came from the factory. It doesn't seem to be easily adjusted.