Electronics Forum | Tue Mar 01 15:07:00 EST 2011 | dennisfo
Update on 1B73 bubbles, Changed over to a mixture of Humiseal 73 thinner with coating (25 sec on Zahn 2) observed a reduction in bubble formation (approx. 20%) but still present.
Electronics Forum | Fri Feb 18 08:08:55 EST 2011 | floydf
I have found that depressurizing the tanks when the machine is not in use reduces bubbles.
Electronics Forum | Tue Mar 01 15:33:35 EST 2011 | jlawson
If I assume you running a selective coating machine ? Maybe you have small leak and system is sucking in air creating bubbles in mixture, like a sort of venturi action, just idea, can be a faulty fitting , elbow etc. Have had this before....
Electronics Forum | Tue Feb 08 14:23:47 EST 2011 | dennisfo
Conformal coat bubbles using 1B73 and SC-205 nozzle I've read most of the posts on this subject. I'm using the SC-205 (airless) fan nozzle and 400 needle to apply 1B73 mixed with xylene thinner. I have micro bubbles which come directly out of the noz
Electronics Forum | Fri Mar 04 10:45:43 EST 2011 | dennisfo
I'll try to get some pictures using the Ersa scope this afternoon. Not sure how to post them,may try to send directly to you.I'll take some immediately after coating then of the same after a flash off period.
Electronics Forum | Wed Feb 16 12:22:54 EST 2011 | duso02
Have you always used xylene? For our 1B73 we use nothing but 73 thinner from Humiseal or PGMEA at about 50/50 depending on the humidity.
Electronics Forum | Fri Mar 04 07:31:51 EST 2011 | duso02
Dennis, I'm amazed that you are having this much trouble. Not trying to be a smart-a**, it's just that 73 is usually pretty easy to fix. Is there anyway you could send me some pics of what you are seeing?
Electronics Forum | Fri Feb 18 12:00:08 EST 2011 | dennisfo
That has also been the standard here. We have a urethane line which pulls a vacuum on the mixture before transfering to the can. I plan on testing this out before receipt of the 73 thinner. I've also received some feedback with indication that the mi
Electronics Forum | Wed Feb 16 12:47:58 EST 2011 | dennisfo
I've been here approx. 3 months. It was indicated that Xylene has alwas been used but it was never indicated that bubbles were not present in the past (ignored or touchup). I have a sample of Humiseal 73 thinner ordered for testing. We've been thinne
Electronics Forum | Tue Jan 24 21:07:17 EST 2006 | davef
We all genuflect to Graham Naisbitt, a generous contributor to SMTnet. Moisture-curing urethanes may form minute bubbles if the coating is too thick or the coating environment is too humid. So, tell us more about your urethane and the method you u
