conformal coating PCBs with onboard connectors

Win, I don't know (so maybe I should just shut up.) But I'm going to suggest calling/emailing/ some places and see what they say. If you are doing a small run ~100 or less then you want to find a small guy who will work with you a bit. Maybe you can have connectors waxed or covered.. Are you in a hurry? Of course the small guy may cost more.

George H.

I'm sure they must have tricks; I've seen conformal coatings on boards with edge connectors, after all.

One approach I've used, is to get a latex molding compound (TAP plastics sells it in tubs)

and blob it over the parts you want protected. After it dries, it's easy to pull off (and it's water-based, most hydrophobic coatings won't attack it).

Another old solution is 'washable solder mask', but that's a ... different kind of coating.

We used to use that to keep solder off. Put it on with a nozzled bottle. It just rubs off with fingers after processing.

NT

The assembly house I use a lot does selective conformal coating. The machine they're using is Dima HC-200 dispenser, which can selectively spray the coating and leave holes for test points and connectors.

snipped-for-privacy@gmail.com wrote in news: snipped-for-privacy@googlegroups.com:

Yeah... That was the pink stuff sometimes powder blue. But we masked off any through holes or via that were needed downstream of the wave or reflow step. If the connectors are through hole, then mask the holes and solder the connectors on by hand after the wave or reflow, Or douse the whole thing in the mask, cause it peels right off like you said.

I would worry about small for factor high pin count connectors as the pink stuff could get under the pins and alter connector function / continuity integrity., even if it wipes clean from their surfaces.

I just probe through the coating. Today's coatings are invariably self- healing IME.

Cursitor Doom wrote in news:q9vdus$2u4$ snipped-for-privacy@dont-email.me:

Absolutely not. Any breech means that water can then invade the very thing you were sealing against. And no, regardless of how you think the material 'feels', it does not 'self heal'. Erroneous 'estimation'.

Repair work on coated mil PCB assemblies requires the worked areas be resealed. So, since they know what they are doing/talking about, I am pretty sure commercial work follows. If it needed conformal coating to start with the reason is almost always moisture barrier related.

We use Techspray's WonderMASK (the pink kind). I find it very easy to work with. Goes on easy, comes off easy, does a brilliant job.