Stopping screws coming loose in vibration motor

Try searching for potting compound, but a bit of Loctite, or even varnish might be more useful if you ever need to get into the box again.

Mark Rand RTFM

I think that what you are looking for is RS stock no. 2508566520

Or just google for electrical sealing putty

-Mark

On Fri, 19 Jan 2007 13:26:29 +0000, Mark Rae wrote (in article ):

Almost correct, this might do at a push.

Last time I scrounged a piece that looked like half a bar of polishing compound, texture like putty, a dark reddish brown. Was wrapped in greaseproof type paper.

The part number you gave is insulation putty in strip for, I could do it in layers.

Good thing about the putty I had last time is that it will push in every corner surrounding all the insulation posts.

Thanks

LIonel

PS I did ask about using lock-tight but company I bought the motor from advised against it.

The company I work for sells equipment into high-vibration environments. Although screws etc. are usually loctited, components that are in danger of shaking are usually given support with some silicone rubber. Make sure you use the sort intended for electronics, that DOESN'T give off acetic acid as it cures. It's not too difficult to peel off if youi need to gain access to the screws.

I've seen some manufacturers use hot-melt glue, but it doesn't stick very well if applied to cold objects. It's supposed to be better if you can warm the item before it's applied.

-adrian

The most important thing to get right when you're trying to prevent fasteners coming loose is sufficient clamping force. If the clamping force exceeds the other vibration forces trying to loosen the bolt it will stay tight. Research in Germany in the 60s found that conventional spring lock washers, those split things with sharp edges, actually helped joints loosen off rather than the reverse. They've been superceded now by things like Philidas nuts, Nyloc nuts and chemical adhesives. None of these will counter the effects of insufficient clamping force though.

I'd slap the strongest Loctite you can find on everything and do them up until they squeak. If they still come loose you can use electrical potting compound but then you'll never get the thing apart again because it sets like rock. I'm wondering if ordinary glazer's window putty might work. It sets hard but brittle so you can chip it out again.

-- "I found this stone in the park yesterday. It's been worn to a perfect sphere by the elements and dimpled by time." "Harry, that's a golfball!" (3rd Rock From The Sun)