Electronics Forum | Thu Feb 17 15:01:23 EST 2005 | davef
We're not familiar with your DYMAX #984-LVUF. The problem is not with your conformal coating. The problem is with your 0805 [and not all of 0805, probably just those from a specific supplier]. This lack of coverage of components is called dewetting
Electronics Forum | Sun Apr 10 03:25:35 EDT 2005 | Peter
Normally, some conformal coatings do not have very good wetting properties, that should be basic function of a good coating material (the same reqirement as avoid bubbles during coating process)! For UV curing conformal coatings, you can try Lackwe
Electronics Forum | Fri Feb 18 11:25:14 EST 2005 | davef
It's weird that it would be just 0805. When we see this it relates to a single part number and it goes way after a time. We use a Humiseal 1B73. I've emailed you the contact for a person that is very knowledgeable on conformal coatings.
Electronics Forum | Mon Mar 21 09:23:34 EST 2005 | sforman1
Some UV cure coatings do not have the correct rheology for sticking to small sharp corners. 984 is one of them. MicroCoat Technologies, Allen, TX makes one that works every time.
Electronics Forum | Wed Feb 23 10:01:00 EST 2005 | frankracine
Dave, Few questions concerning your Umiseal 1B73. To cure your Acrylic coating do you respect specification ( 2Hrs-170degree F) or you go faster than that? What do you use to cure it? Do you have to clean your nozzles each day or each monday beca
Electronics Forum | Thu Feb 17 10:33:53 EST 2005 | Frank R.
I use conformal coating DYMAX #984-LVUF and I don't know if it's a problem of viscosity but 0805 components are not covered properly. We use a dispensor to applied it and we cured it by UV. Even if I apply a thicker layer, the coating seems to have
Electronics Forum | Thu Nov 23 06:05:24 EST 2006 | 1B73
The solid content of 1B73 is too low, especiall when you add large amount of thinner, not easy to get enough coating thickness.
Electronics Forum | Wed Feb 23 22:38:28 EST 2005 | davef
We: * Cure 1B73 according to spec in a heat box, like a Blue-M * Clean nozzles [one set in use, one set being cleaned] in thinner in a bronson ultrasonic cleaner * Haven't evaluated coatings in years, but would do it according to J-STD-001C, Reqmnts
Electronics Forum | Fri Feb 18 10:10:49 EST 2005 | Frank R.
Thanks Dave, The problem is on all 0805. Do you think it could be a reaction with the flux from the wave or the one in the paste. Do you think the problem is the viscosity of the coating. SPEC = Viscosity 150cP nominal ASTM D-1384. I ask you all
Electronics Forum | Fri Feb 18 15:27:38 EST 2005 | jluckenbaugh
Frank R, I believe the Dymax #984-LVUF is a POLYURETHANE RESIN. I have used Humiseal 1A27 and 1A33 for several years with great success. Both of these materials are High VOC materials. If your customer does not require these materials to be aproved
