Lou, Solder float (for PWBs solderability; surface pads and PTHs) is done in a solder pot at 245C +/- 5C for 5 seconds maximum (and as normally you don't want to fail, you test as close to 5 seconds as you can). See section 4.2.3 of ANSI/J-STD-003 (available from IPC). These parameters are unchanged from IPC-S-804A (which was superceded by ANSI/J-STD-003). Note that this test is designed to evaluate the solderability of the specimen and isn't really a "worse case" thermal shock test for PTH durability. If you are interested in the PTH durability, I would recommend the following (taken from MIL-STD-55110D). 3.9.2 Rework simulation, plated-through holes. Types 2 and 3 printed-wiring boards shall be inspected in accordance with 4.8.6.2. After the fifth cycle of soldering and unsoldering of the test wire , the plated-through hole shall exhibit no plating cracks, blistering, or delamination in excess of that allowed in 3.5.3. Laminate voids in zone B (see figure 8) with the longest dimension of 0.003 inch (0.08 mm) or less shall be permitted provided all minimum dielectric requirements are met. Resin recession at the outer surface of the plated-through hole barrel shall be permitted and is not cause for rejection. 4.8.6.2 Rework simulation, plated-through hole (see 3.9.2). Rework simulation of plated-through holes shall be in accordance with IPC-TM-650, method 2.4.36. Following the fifth cycle of soldering and unsoldering of the test wire, the plated-through holes shall be microsectioned and inspected in accordance with 4.8.1.2 and mneet the requirements of 3.9.2. The rework simulation shall be performed after stabilizing of the coupons at temperatures of 59øF to 95øF (15øC to 35øC) and relative humidity of 40 to 85 percent for a period of 24 hours. Hope this helps Jim Maguire Principal Engineer, E/E M&P (206)657-9063 Boeing Defense & Space Group [log in to unmask] ______________________________ Reply Separator _________________________________ Subject: Solder Float/Shock Testing Author: [log in to unmask] at esdigate Date: 8/22/95 11:38 AM Hello all: We would like some information on temperature and time required prior to testing a sample in the solder pot for solder float/shock testing. We checked in the IPC Test Methods but could not find the specific information that we were looking for. Any help would be greatly appreciated! Sincerely, Lou Cerone, Process Engineer Benny George, Quality Control Tech