A. The residue in dissolved flux that has not been washed off the board. Cleaning flux off a circuit board is more involved than simply spraying a cleaner onto it. IP R TANT Removing flux is a two-step process. The first step is dissolving the flux. The second step is rinsing off the dissolved flux. The rinsing step is very important because after dissolving the flux it may appear that the solids in the flux have disappeared, but once the flux remover has evaporated away, the solids will re-deposit on the board as white residue. C:Chk,whfxrdbrd Step 1: Dissolving the Flux If you are using flux remover in aerosol form, spray a little flux remover onto the flux, then agitate with a hog hair cleaning brush. If you are using our 4140 Flux Remover, you may spray it liberally, as it is safe on your components. If you are using 413B Heavy Duty Flux remover, you may spray it liberally on the solder side of the board, but be careful to only apply it directly to the flux contaminated area if you are using it on the component side of the board, as it will harm some components. The 4140 is plastic safe so it may be applied liberally. Have a can of 413B handy in case you run into a patch of burnt-on difficult to remove flux. If you are using flux remover in liquid form, pour the flux remover into a tray. If you v are using 4140 Flux Remover, you may then submerge the PC board into the tray, q agitating the flux with a hog-hair brush. If you are using 413B Heavy Duty Flux v Remover, you should not submerge the board into the tray, as the components will be damaged. Instead, wet the hog-hair brush you are using by dipping it into the tray, and then use it to agitate the flux on the board. Periodically rinse and re-wet the brush by swishing it in the flux remover. AG C hf x r v r r R H SC N MG Chemicals AppGuide One company. Many solutions. Step 2: Rinsing the Board You must ensure that you rinse off the dissolved solids completely before the flux remover evaporates and the solids re-deposit. If you are using flux remover in aerosol form, the easiest way to do this is to hold the board vertically and liberally apply more flux remover until you see the flux remover running off of the board. If you have dissolved the flux by submerging the board in liquid flux remover, just dip Aerosol cleaning method with the board into the tray and swish the flux remover and you should be ok. 4140-400G Plastic Safe Flux Remover or 413B-425G Heavy Duty Flux Remover If you have been using the particular tray to dissolve flux on a number of boards, When rinsing many boards, dissolved flux may accumulate in the tray and dipping the board may actually dissolved flux may accumulate deposit flux solids onto the board. In this case you will want to either set up a in the tray and dipping the separate tray for rinsing, or have an aerosol can handy for rinsing. A particularly board may actually deposit flux good option for rinsing dissolved flux off of a board is to use our 406B Super Wash. Super Wash comes in a large aerosol can, allowing for liberal use, and it solids onto the board. dries very rapidly. Super Wash will rinse off un-evaporated flux remover as well as flux solids, and almost immediately after rinsing your board, it will be dry and ready for service. Tray method with liquid flux remover Products Discussed Stock Code Product Name Size Form 4140-400G Plastic Safe Flux Remover 14 oz (400 grams) Aerosol 4140-500ML Plastic Safe Flux Remover 17 oz (500 ml) Liquid 4140-1L Plastic Safe Flux Remover 33 oz (1 liter) Liquid 413B-425G Heavy Duty Flux Remover 15 oz (425 grams) Aerosol 413B-1L Heavy Dusty Flux Remover 33 oz (1 liter) Liquid 406B-450G Super Wash Cleaner / Degreaser 16 oz (450 grams) Aerosol 852 Hog Hair Cleaning Brush 7 in length Brush Larger sizes available for liquid forms. For technical specifications, To customize this AppGuide E-mail salesusa mgchemicals.com MSDS, tech support and more for your own use please email Phone 1-800-201-8822 1-604-888-3084 www.mgchemicals.com info mgchemicals.com Fax 1-800-708-9888 1-604-888-7754 IISSOO 99000011::22000000 RReeggiisstteerreedd QQuuaalliittyy SSyysstteemm.. QQMMII CCeerrttiiffiiccaattee 000044000088 TToorroonnttoo,, CCaannaaddaa..