Ways to encapsulate my circuit

Hi guys, I am developing a circuit and I want to encapsulate it. This circuit is a reed switch and a resistor...not more. I want to do the circuit more robust because it will be mounted in a bike... And of course, maybe will have a more serious aspect. So... What ways do I have in order to encapsulate my circuit? Do you know companies that encapsulate circuits? Does exist some software to do it...just like fritzing to create boards? And some way to do it at home? Thanks in advance, Anton

Do you have wiring to it as well?

Do you anticipate needing to 'unencapsulate' it in future for repairs? If not, simply dunking the wires plus circuit in liquid rubber would give you a waterproof coating and a small amount of mechanical protection. If you want more robust protection you could coat it in epoxy. I think the professional approach would be to place it in an enclosure and fill the enclosure with a potting compound, which is usually epoxy or some form of plastic.

There are ways to encapsulate, or pot, electronics at home. Probably the most robust would be to start with small container made from a hard plastic, then mostly fill it with epoxy, and hold the electronics about halfway down the container until the epoxy cures. However, cheaper and less time consuming methods would be to completely surround the components with either hot glue or silicone caulking, either normally mounted on a PCB or encasing them separately.

Edit: PeterH beat me to the post.

Hi guys; Thanks for your comments, have been really useful! Do you have a link explaining a procedure to do it on home or something realted? I think that there is no need to 'unencapsulate' it in future for repairs, because is just reed switch sensor... Thanks Anton

Well I gave a basic description of one effective process for using expoy. If you were to use something like a silicone caulk, you’d need something to hold the resistor and reed switch after soldering. You could use a small vise or a thrid-hand, even a pair of clothespins, anything that will allow you to apply the caulk around both components and allow it to cure for 12 to 24 hours without touching anything. If you are using hot glue a vise or third-hand would also help, but it would take less time for the glue to cool than silicone to cure.

Whatever you encapsulate the parts in make sure it yields a water-tight seal that can also absorb some physical shocks and is electrically non-conductive.

By the way it is possible to buy reed switches that are already encapsulated, some even in packages with mounting slots.

You can buy plastic “potting boxes” designed for just this application.


Just stick your board in the box and backfill with the potting gunk.


You might want to look into ordinary foam that is used to seal household air leaks…Rigid foam is very low cost and
has a low dielectric constant…This keeps stray capacities as low as possible(air being the lowest)…
This may not be as important in your particular circuit but in some cases strays can cause peculiar glitches.
Just dont use too much foam so that you over compress the circuit…practice, practice, practice before committing your device as others have said can be very hard to undo and or you may lose it.