The plastic top of the stylus for the Sony PRS-350 eventually breaks, making it useless. I repaired my wife's stylus three years ago, and today the one for mine. Here's how I did it. First, I drilled a hole in the broken off plastic going down into the aluminum tube. The hole is drilled straight down into the aluminum tube I used a 1/16th inch bit. The drill penetrated over 1/2" before going on through.
Then, using a very small bladed screwdriver, I picked at the plastic until I had about 3/16" of it removed, so the inside of the aluminum tube was plastic free for that distance.
Then, I screwed a stainless steel 4-40 X 1/4" pan head Phillips screw into the tube. The screw is slightly too large for this and I could only get about 4 threads deep - but it is enough! If you can get it, a thread-cutting screw might be even better. A sheet metal screw might work well too - but the 4-40 screw was what I had. Note that most hardware stores now sell stainless screws in single quantities - if you need to buy one I'd get a couple.
Bottom line - the fix works fine. My wife's has lasted three years without the screw ever coming out, and lets her use the stylus regularly. The fix lacks elegance - but it works!
Then, using a very small bladed screwdriver, I picked at the plastic until I had about 3/16" of it removed, so the inside of the aluminum tube was plastic free for that distance.
Then, I screwed a stainless steel 4-40 X 1/4" pan head Phillips screw into the tube. The screw is slightly too large for this and I could only get about 4 threads deep - but it is enough! If you can get it, a thread-cutting screw might be even better. A sheet metal screw might work well too - but the 4-40 screw was what I had. Note that most hardware stores now sell stainless screws in single quantities - if you need to buy one I'd get a couple.
Bottom line - the fix works fine. My wife's has lasted three years without the screw ever coming out, and lets her use the stylus regularly. The fix lacks elegance - but it works!