Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

No Clean Solder Paste



No Clean Solder Paste | 15 November, 2004

Has anyone used no clean solder paste and if you have what are some of the pros and cons with this product?

Thanks in advance Marzz

reply »


No Clean Solder Paste | 15 November, 2004

In the most straight foreward terms, low residue fluxes are: * Less expensive than other flux types from an equipment purchase stand-point. [Obviously, this is a benefit to only those either without equipment or readily able to dispose of the equipment.] * More expensive than other flux types from an process control stand-point [Some low residue flux users seem to ignore this part of the equation, thinking there's a free lunch. Tsk, tsk, tsk.]

For more on fluxes, look here:

reply »



No Clean Solder Paste | 17 November, 2004

Pros are no need to clean after reflow. No need to buy a cleaner or worry about "wet" parts afterwards when you're trying to test your unit.

Cons are that most leave a bit of a residue behind. It's harmless but may drive your bed-of-nails tester a bit buggy if your test points are probing the solder joints. If this is your first turn at no-clean, you'll probably notice an increase of solder balls as well. This is because your cleaner washed em off before. The best way around this is to use the standard homeplate design on your R's and Cs. This prevents th paste to squish out under your Rs and Cs, which causes the solder ball. Also, inspectors may see the no-clean residue under magnification, so some training may be needed as well.

Don't forget to switch all your wire solder to no-clean as well! Many forget this step.

Other than, all profiling and repair should be the same as your old paste.

reply »



No Clean Solder Paste | 17 November, 2004

No-Clean has less activators, your profiling Does change. Look at the data sheet supplied by the solder manufacturer. Then tweak the profile based on your equipment, board type, size etc. Don't burn off the activators too quickly. Also keep your chemistry the same in other areas. IE: No Clean from Aim, Kester etc. That way if there is a problem you only have one factory rep and or disty to deal with. Have a nice day

reply »

Used PCB Equipment - AdoptSMT

SMT Spare Parts and Feeders