Hey KiTas! Just an update on my 3D printer enclosure Here 's a sneak peek I got right to w...

[G+_Jeff Gros]

Hey KiTas!

 

Just an update on my 3D printer enclosure. Here's a sneak peek.

 

I got right to where I was about to assemble it, and I decided to add a smoke detector. Then I decided the smoke detector should remove power to the printer if it detects smoke...This is why I never finish anything.

 

Basically, if you press the test button on the smoke detector, it causes a current imbalance, which causes the GFI to trip. If I had the printer plugged into the outlet, it would lose power.

[G+_Rud Dog]

Now add a fire extinguisher. The idea of cutting power if smoke/fire is detected sounds like a great idea especially if there is a fire. Maybe place a second smoke detector outside the enclosure if both detect a problem then cut power and release the extinguishers.

[G+_Mike Siefker]

Rud Dog what about a strictly battery operated smoke detector?

[G+_Rud Dog]

Mike Siefker Hmmm. Batteries can be so unreliable and if incorporated, a ckt to detect a battery loss would have to let the user know whether home or not.

[G+_Jeff Gros]

Rud Dog Some enclosures do have built in extinguishers that release on sensing smoke. I'm going for a different approach. The enclosure is going to be made by polycarbonate. It will burn, like just about anything, but it isn't self sustaining like acrylic. Remove the ignition source, and it will stop.

 

Basically, I figure that the main fire hazard with a 3D printer is going to be from wires coming loose (I often describe 3D printers to people as vibration machines that happen to melt plastic as a side effect).

 

I did have another smoke alarm in the ceiling of the room the printer was in, but it recently went bad (alarm chirps regardless of fresh batteries). My alarms are overdue for a replacement, so I'll replace the lot. Until then, no overnight printing or printing away from home!

[G+_Jeff Gros]

Mike Siefker The Prusa enclosure template that I'm copying/modifying uses a battery operated smoke detector. Probably more because they didn't want to make enclosure instructions that had people messing with mains wiring. Nothing wrong with that. Battery operated works fine.

 

I'll think I'll be running this one without a battery. If the smoke alarm loses power, so will the printer. So fire in the enclosure is not likely at that point. I also don't want my neighbors to get upset if I get a false alarm while away from home and the battery keeps it alive.

 

Its a bit hard to tell in the picture above, but there are actually two cables that come into the box. There is a black one (difficult to see), which supplies power on the line side. The white cable is the load side, which powers the smoke alarm from line.

 

In my setup, if the smoke alarm trips, since it is on the load side, it will lose power along with the printer (which I would plug into the GFI). Everyone is safe and unpowered....and also quiet! :)

 

Also hard to see in the picture, the smoke detector has been modified, as this is the one I used for testing. It has superglue in the buzzer cavity to push it out of resonance so that it is no more noisy than a microwave buzzer. I'll use the real thing for the enclosure of course.

 

The white square thing with the two prong plug is just a night light I used for testing.

[G+_Rud Dog]

Can't wait for the maiden voyage.