Electronics Forum | Fri Aug 11 06:48:38 EDT 2000 | GJ
I am currently building boards which have to be conformal coated (done by an outside source) in a no clean process. The conformal coating however, must be applied to a clean surface. The flux residue left from the paste has come into question. I h
Electronics Forum | Sat Aug 12 09:47:36 EDT 2000 | Dave F
GJ: If your supplier uses a conformal coating that "must be applied to a clean surface," then you are using the wrong supplier and no amount of twiddling with your N2 levels will change this. NC fluxes are inherently "dirty" and nothing aside of cle
Electronics Forum | Fri Jul 04 05:40:09 EDT 2008 | proy
Thanks, I'll give this a try. Peter
Electronics Forum | Thu Jul 03 19:27:54 EDT 2008 | proy
5 Zone HVA70 Oven Board 6 layer, 10" x 13" lots of space, most critical is 100 pin QFP AIM Water Soluble 487 Tin Lead paste on SN100C HASL boards This board is giving me disproportionate grief! I am running 23 in / min which gives me about 3.1 mi
Electronics Forum | Fri Jul 04 00:36:25 EDT 2008 | shrek
Try a linear, very flat ramp rate on the order of 0.5 degrees celcius per second. I know this is hard to accomplish with a five zone, but try to lower the first couple of zones (the preheat zone), and then spike to reflow aggressively during your la
Electronics Forum | Thu Jul 10 10:25:05 EDT 2008 | gregoryyork
I guess the paste is Leaded hence the 220 Peak temp and the Sn100c is Eutectic at 227C so you need to be hotter to melt the HASL finish or you are relying on it alloying together with the paste which takes much longer. suggest running peak temp of 23
Electronics Forum | Tue Jul 08 22:44:06 EDT 2008 | proy
I made progress and almost acceptable results by adding heat to the bottom of zone 4 HOWEVER, the core problem I uncovered last night/this morning was that the #4 top side blower had failed. I think this is the key why I was having so much trouble.
Electronics Forum | Wed Jul 20 16:02:05 EDT 2005 | Inds
guys, I am having a problem. During my rework (SRT) process, I am trying to reach a board temp of 150degC b4 the top heater comes down for the actual rework process. Due to which the flux (tacflux 20)is burning off and i am seeing lot of non wetting
Electronics Forum | Wed Jul 20 18:08:38 EDT 2005 | russ
How long is it taking to reach the 150? We use the 020 here along with 023 and have very good results with our machine. The 023 is rated for a higher temp then the 020 but I don't know about staying power. We heat from both the bottom and the top
Electronics Forum | Mon Dec 30 12:55:37 EST 2019 | emeto
We saw your profile, which in my opinion looks alright based on the guideline from the vendor. Can you tell us more about the joints that you cleaned? Are they showing nice wetting and nice and shiny finish? How about your stencil thickness? From my