POTTING SWITCHES

[john price]

Hi all,
What is the best material for potting switches, plugs and sockets? Are 5 minute epoxy or hot glue any good?

John.

[john greenfield]

Hot glue is my preferred option, especially if injected into the metal moulds that are now available but equally OK to form by hand.

AEB

[wookman]

Hi John.
I would be inclined to use a slightly slower set epoxy. I have used three hour and twenty four hour for such work successfully on mpx and serial connectors. Do double check that it all works they way you want it to coz there ain't a second chance once it is potted. Go on ask me how I know, actually don't!

[Peter Balcombe]

John,
I can echo what Wookman says as you need something which is fairly viscous to stop it running into the works before it sets

[spike spencer]

Hot melt glue is preferable as it leaves a flexible area where the leads emerge for strain relief. Epoxy is likely to produce a rigid termination, promoting early wire failure at that point.
With hot melt glue, a hot air gun can re-soften the mass to allow reshaping and also enables later correction of mistakes.

Silicon sealant also works but is messy, smelly and is a one-shot answer with little hope of later adjustment. Having said that, I regard a 'failed' switch lead as a consumable item. Quicker and more reliable in Airworthiness terms to start afresh. Get it right first time !

[john price]

Thanks chaps, all very useful advice. The flexibility of the hot glue sounds good,

Cheers,
John.

[john greenfield]

I have to agree with Spike which is why I suggested hot glue over epoxy. The hard edge of epoxy can lead to wire failure especially if the wire is subject to any flexing such as continually inserting and removing plugs or any vibration.

AEB

[Graham James]

Thanks chaps, all very useful advice. The flexibility of the hot glue sounds good,

Cheers,
John.

Expensive but for the professional finish I know you like John, here's the mould mentioned above.

G

http://www.esoaringgadgets.co.uk/index. ... cts_id=423

[spike spencer]

Easy to make a one-off mould from scraps of wood. If the release agent works, you may get a couple of goes from it. Cost - nowt !

[john price]

Too late, it's done! It was for the back of a double toggle switch which will never be seen so it got a nice blob of hot glue.

Thanks again.