Braun Electric Razor Repair
2016-03-05 11:13 - Making
Just under twelve years ago, I bought a Braun 7505 electric razor. I like this thing. I've needed to replace the blades several times, of course, but overall it's worked very well over time without any issue. Except the batteries. One of my favorite features was the batteries, meaning it need be plugged in only to charge, not to use. But the batteries didn't last. I finally decided to see if I could do something about it.
At first I found only one relevant page online: How to change the batteries in a Braun 7505 Synchro Shaver. It complained of a bad similar explanation on eHow (which I've not read), which referenced a manual without any instructions. So I found the Braun SyncroPro Manual and indeed, it has no instructions to describe replacing the batteries. But the Korean Syncro Manual does have these instructions, on page seven.
I've reproduced that image on the right. It's got unrelated English text on the page, but it's a nice visual description of the necessary steps. I found that prying the outermost cap (step 2) works best by grabbing the inner edge of the opening for the plug. I couldn't (confidently) get something around the edge like pictured without damaging it. Once that cap is off, the sides come off easily by hand, and some T9 torx screws hold the back on. With that removed the power board comes right out, it's held in place only by the structure just disassembled.
The original batteries have tabs welded on, which are soldered into the circuit board. (Maybe Korean models aren't welded in, thus the instructions in their manual?) I popped the tabs off by prying with a knife, which damaged them only slightly. With some replacement (NiMH) batteries in hand, I cleaned their terminals and heavily tinned them with solder, then set them next to the tinned tabs, then heated the whole lot until the solder melted together again. The original batteries were also stuck down with adhesive; some hot glue took that place with my replacements.
After reassembly, I've finally got a cordless electric razor again! I delayed this repair so long, it will actually be hard to get used to.
