TIP: Dusty Switches - or - Never gonna do it without your fez on...

That is a tip worthy of sending to the magazines. They are always looking to fill space and will pay you if they use it.

Nice one, thanks

I have a switch acting up right now, may put this one to use tomorrow.

Mike Mike Patterson Please remove the spamtrap to email me. "I always wanted to be somebody...I should have been more specific..." - Lily Tomlin

Possibly, but I'll probably never get around to it. Thanks - hope it proves useful.

Of course, you can buy commercial dust-proof switches, but they cost a bit more than the $1.49 switches they put in houses these days, and sell at the BORG.

FWIW

Thanks, glad the idea may be of use to someone.

I hit the switches with compressed air whenever I blow the lathe off.. might help, but I think the switch condom idea might generate more interesting conversations in the shop.. *g*

Practice safe switching?

Mac

Yeah, ask Ellis Walentine about dust in electrical fixtures..... a sad story....

Shoulda known someone would post an utterly depressing story like that. Having been the victim of a similar fire many years ago, I am even more cautious now than I was then about fire safety - and the idiots who will do anything for a damned buck.

That is one unhappy camper, I can guarantee. Shocking reminder of what can happen, but still a depressing story...

Although a very clever solution, I would be concerned about what happens in the long term. Does nitrile breakdown? In a closed environment where the air may be highly ionized? If so, will it breakdown into something that may facilitate arcing? I doubt it, but I certainly don't know. It looks like the current unsealed situation is a ticking time bomb -- accumulating fine dust. But if you're going to fix it, why not use something which has been tested, approved, and blessed by experts? At least you won't be buying a dispute with your insurance carrier should they wonder if your modification may have contributed to the problem and thus jeopardize coverage.

Also, think about down the line, what if you sell and the new owner ends us having a fire with cause being determined to have started in the box? Again, I'd be inclined to think the nitrile fix would not be a cause, but I can't say I wouldn't rule it out entirely. Would you entertain any feelings of responsibility with an unapproved modification you made whose interaction in the facts leading up to the fire is unknown?

I'm not assessing whether this modification is good or bad, I'm just raising the issue of making any unapproved modification to something that undergoes a rigorous standards/testing procedure where consequences can be disastrous. Just some concerns.

Yes, there are three concerns here; for fire safety, some materials aren't good inside the switch area (and ozone from a switch might make nitrile into flammable goo). Second concern: the amount of sawdust that kills a switch can be explosive. Third concern, of course, is that the switch work reliably.

Two other solutions are mercury switches (these have a tilting sealed capsule with mercury, and no dust can stop their normal function as long as the toggle still moves), and explosion-proof switches (which are skeleton switch mechanisms, so gases cannot get trapped, and with a conformal rubber coating so sparks at the switch contact aren't communicated to the ambient, whether sawdust or bilge gases).

But the best solution is to use good dust collection whenever that darned sander is in use, even if it's just a shop vacuum and a feather duster.

There's probably a reason beyond what is being discussed here, why your switch boxes are full with wood dust. Normally dust just settles down, and does not go into closed confined places unless an air current takes it there, the way we build walls, the spaces between the studs and wall boards become wind tunnels in a way when we have openings (however small) that connect one space to another, and temperature or pressures are different between them.

Wind on one side of a building will create pressure on one side and a negative pressure on the other side, and air will travel through every opening taking along in this case wood dust and also the same thing happens with cold verses warm air.

Take some foam in a can and fill the area around your switch box to minimize or eliminate the airflow, and you will also eliminate or minimize the dust into the switch box and create the switch problem.

Also there are special designed seals for use between switch box and switch plates to lessen air leaks in houses, they by themselves would help to prevent much of the dust problem you have.

Have fun aand take care Leo Van Der Loo

DGG wrote:

what's wrong with using a MIL SPEC sealed switch?

The switch will work fine but if the folks in DC get word that it is being used by a non military person they may send the Delta crowd out to get you.

Brian

just because you are paranoid doesn't mean that they aren't out to get you.