Ok so for me, spray fluxing is the way to go every time....for one you don't need to worry about colapsing your foam with pallet's that are hot or worrying about your pummace, your thinners, SG and so forth...man life in foam fluxer land was hard.
Now Spray fluxing...that's easy right?..well yes n no, like I said all the stuff above goes but there are new things to worry about. First off how much flux is enough flux?, you've got to figure out what the right amountof flux is for the board, now most flux manufacturers will tell you what they think a good tart point is, generally you're going to be in the range of 1.2-1.8 grams of flux per card for your normal 3% solids. You' ve also got to look at your spray pattern, how many head's are you using, are you getting banding?, the pitch of the spray head has a big effect and you have to match this with the conveyor speed to get a full coverage. There is also the nozzel selection, and angle for the spray, these again are dependant on your application, and the flux...
John
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