2014-01-03

Fixing my Wahl 9918 Groomsman Beard and Mustache Trimmer

Not everyone would bother repairing a $20 beard trimmer, but why not fix something for under $5 instead of spending another $20?

My Wahl 9918 Groomsman Beard and Mustache Trimmer has admirably performed its beauty duty for many years, but the time came when the battery just wasn't holding a charge any more.  Most people would just put the trimmer in the trash and buy a new one, but I figured I could repair my Wahl and save some money.

I opened up the Wahl by popping off the black plastic faceplate with a tiny flathead screwdriver, which revealed two screws.  By removing the two screws I was able to easily open up the unit, revealing the guts of the device.


Backplate off, Revealing the screws


The internals are rather simple: a motor, a simple circuit board, a switch, and a NiCad battery pack soldered into place.
The Internals, with new battery pack

I decided that the battery was no longer good, so I worked to replace it.  I bought two NiCd Rechargeable AA Cells with Solder Tabs.  The solder tabs are key - they make it reasonably possible to solder together a new battery pack

To create a new battery pack, I used some electrical tape to wrap together the two new cells, in plus-to-minus orientation.  Then I used a trusty soldering iron to solder one of the plus/minus tables together.  I pulled the foam off the old battery pack and stuck it onto my homemade pack.

Then I unsoldered the old battery pack from the Wahl and soldered the new pack in, ensuring that I kept proper polarity.

After, I cleaned up some corrosion on the switch with a pencil eraser and an emery board, and reassembled.  A little test proved good, and so I plugged in the trimmer and let it charge overnight.

Now the Wahl works like new! It runs perfectly and charges perfectly to.  It continues to provide me with a beautiful beard, 12+ years running.

1 comment:

Shane Kindel said...

Thanks a bunch. Mine is 10 plus years as well and lets fix it not toss it. Very helpful just ordered the batteries and hope these old hands can solder like the old days.

I wish you well


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