Fire

Fri Sep 27, 2019

Yesterday I tested my new, self made nail bed. Which consists of a steel plate and 40mm long screws, which are glued to a magnet. It worked very fine for acrylic but when I tried to cut corrugated cardboard carton it ignited. Luckily (ok, I'm always watching the laser) I immediately saw it and pressed "stop" on the controller, took out the carton and went to the sink.

So the lessons to be learned :

1. Don't cut this kind of carton on a nail bed (fumes ignite easily).

2. Always watch your laser, ALWAYS.

3. Have some water at hand, I now have an empty windows cleaner spray bottle filled with water. SECONDS COUNT!!! Until you have to run to the sink, find a pot, have it filled with water, run back, everything could be havoc.

4. Have a fire extinguisher at hand (which I have, just not the expensive one, so before I use it I have to disconnect the machine from power, takes expansive seconds!).

5. Shame on me, but could happen to everyone, so this is the reason for this post.

Be save!

Edit: Any tips or good advice, please be welcome to share!

Fri Sep 27, 2019

I watched a russ sadler video recently, it recommended using dot mode for cutting corrugated cardboard as it uses pulses rather than a continuous cut.
Also some good info concerning appropriate power levels.

I recently did a trial using dot mode, it created a perforation type cut, which suited the cardboard well, worth a look into

Fri Sep 27, 2019

Murphy's law: "If you have a fire extinguisher, water at hand AND watch out, nothing will ever happen ...."

Have to look out for the video, I thought I saw them all...
PS: Thanks for all your videos, Russ!!!!!!

Sat Sep 28, 2019

Philipp Pap wrote: Fri Sep 27, 2019 Murphy's law: "If you have a fire extinguisher, water at hand AND watch out, nothing will ever happen ...."

i'm totally fine to have an extinguisher that i will never need to use against a fire!!!

same for the glasses.. you will never have a stray beam in the eye if you care to wear glasses (especially when aligning mirrors)

Sat Sep 28, 2019

Philipp Pap wrote: Fri Sep 27, 2019
Have to look out for the video, I thought I saw them all...
PS: Thanks for all your videos, Russ!!!!!!

The video on cutting cardboard is (I think) part of his Thinklaser series (not RDWorks Learning Lab series).

Sat Sep 28, 2019

Warning: new laser user, this may be a Noob question (please be gentle with me!)

In case of fire - I would REALLY like to move the laser head out of the way before I spray a fire with water or a fire extinguisher.

Is there any easy was to do this?
How can I stop the program that is running, and send the head to a pre-determined "home" position? (hitting the emergency STOP button would prevent me from doing this, correct?)

Chris

Sat Sep 28, 2019

the e-stop will disconnect power to almost everything on/in the laser, eliminating the possibility of moving the head. Hitting the pause button, then the movement arrows will take an excessive amount of time, in my opinion.

Consider to purchase a gaseous extinguisher rather than a powder type. Halon is no longer available, but halotron is apparently a suitable (expensive) replacement that leaves no residue.

I'd hesitate to use water inside the laser cabinet. Too many high voltage locations and also plenty of steel to rust.

I have an antique CO2 extinguisher that was rescued from trash pickup. It still holds pressure and emits flame smothering gas when triggered, but probably won't pass hydrostatic testing to be refilled when/if emptied. Darn thing weighs a ton, but I figure the adrenaline will compensate for my lack of weight-lifting ability if ever needed.