Thanks for this detail Jeff. I recalled that you are an expert in this! The damage can be quite extensive. This board I was repairing needed some wires pulled through vias under some caps - because the via and pads were totally corroded. Needed the wire to connect both sides of the board together again!
On Thu, May 12, 2022 at 8:14 AM <[email protected]> wrote: > The M100 is one of the few machines I recommend always doing a recap on. > Not all of the caps seem to leak but those that do create a mess and you > wind up removing most of the caps anyhow to clean it up. > > > > Clean up: > > The NiCad battery has an alkaline electrolyte, clean off loose solder > mask, etc. using a fiberglass pen really helps. Neutralize with a mild acid > like vinegar or citric acid. Flush with distilled water and then 99% > alcohol to help get rid of the water. > > > > Electrolytic caps have an acidic electrolyte, clean up the same way as the > battery but use a mild alkaline solution like ammonia or many household > cleaners to neutralize. Flush with water as described above. > > > > I like to then tin the copper, clean away the flux and coat with a trace > sealant. > > > > If the damage is not bad, you may be able to get by with just a cleaning > and wipe down with alcohol. If the copper looks like it’s been etched away > in layers you need to neutralize the area. > > > > If you look up any of the M100 related videos I’ve done, you mill probably > see me doing some of the above. All of them need it done. > > > > Jeff Birt > > > > > > *From:* M100 <[email protected]> *On Behalf Of *Stephen > Adolph > *Sent:* Wednesday, May 11, 2022 10:31 PM > *To:* [email protected] > *Subject:* [M100] more on replacing M100 caps! > > > > I recently took a really close look at an M100 board that died on me. > > > > Actually I am on a mission to fix all my hoard. Going well!. > > > > Anyhow, ... wow some of these caps can do a real number on the PCB. I > know really appreciate all the wisdom around replacing the caps especially > the ones in the power supply. > > > > Question for the group. > > I think you can get corrosion from the nicad spewing gunk OR the caps > spewing gunk. > > > > What's a good way to clean up and neutralize the gunk so you can stop the > corrosion creep? > > > > Thanks! > > > > Steve >
