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Wave Solder Flux Weight

JohnW

#7795

Wave Solder Flux Weight | 18 January, 2000

Hello folk's, long time no chat....

I'm looking for some help, I'm trying to find a formula for calculating flux weight on a VOC flux (Multicores NR3S-06)does anyone have any idea's...Dave????

JohnW

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#7796

Re: Wave Solder Flux Weight | 18 January, 2000

Hey John: Chrys wrote a good description on calculating flux density a while back. Here is our version of her procedure:

4.3 Determine the amount of flux on the board. 4.3.1 Get a piece of corrugated cardboard and a weighing scale accurate to 0.01 grams.

NOTE: Use cardboard with alcohol fluxes to slow their evaporation and get good data.

4.3.2 Weigh the cardboard. 4.3.3 Run the cardboard across the fluxer. 4.3.4 Weigh the cardboard again. 4.3.5 Calculate change in weight / area of the cardboard 4.3.6 Determine flux density. 4.3.7 Ask the flux manufacturer to calculate the flux deposition as: (Change in weight / area) X % solids by weight. 4.3.8 Convert the flux deposition to micro-grams/square inch and compare it to the manufacturer's recommendation.

Good luck

Dave F

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Rex Breunsbach

#7797

Re: Wave Solder Flux Weight | 25 January, 2000

My experience with weighing fluxed boards or cardboard is pretty dismal. Problem is the solvent in the flux evaporates about as fast as you can weigh it. One approach I have seen used to improve accuracy is to weigh and record the weight at 30 second intervals, over a 3 or 4 minuute period. Then you can get a feel for how significant a factor evaporation is.

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