Purchased a WM-10 with plenty of character, and a new belt has it playing great... with a couple of problems. If any of you could provide some of your expertise, I'd greatly appreciate it. During play, there's a bit of friction, especially when the Walkman is on its back, cassette side up, even held up with the case off. I believe this is what docp refers to in his troubleshooting guide: Once the shield plate over the motor is removed the spinning disc with holes in it (Hysteresis plate) is visible normally spinning above the flat plastic plate with coils (the stator coil). Below this is the actual rotating component with a permanent magnet in a disc form. This sometimes ends up rubbing against the motor sleeve assembly below all the more because it unfortuantely is some sort of magnetic stainless steel that loves to have the magnet stuck to it If sony had used some hard plastic/aluminium this wouldn't have occurred. This arises due to a problem with the spacer which actually is visible in a closed walkman from its outer surface as the spindle onto which the gear wheel sits with a locking washer. If this gets displaced outwards even a fraction of a mm it allows the motor magnet to get stuck/scrape and readjusting this is a solid half hour job One thing that seemed to help maintain the space was inserting a thin washer made by cutting a plasticized visiting card using a coin as a cutting templete and then punching acentral hole using a standard paper punch. I inserted this between the coil and the hysteresis plate But before I take it apart, there's another problem, a chip in the plastic gear around the take-up reel. I'm no expert, but I'm guessing it's responsible for the loud kachunk kachunk kachunk during playback. Unless this is normal: I know it will be some work, but I'd love to repair this Walkman without buying a whole other parts unit. What all do I need? Just the gear for the crack, or the whole assembly because of the friction? I appreciate any insight you folks can provide. And if anyone has a donor unit they could recruit from, I'd appreciate the opportunity to purchase the parts I need. I can also post in the Gear You Want forum once I know exactly what I need. Hopefully some of you can point me in the right direction. Thank you again for taking the time to read this post!
After exploring a bit more, it seems like the gear problem has been covered, with the solution being to patch the gear with epoxy. Apparently it's the same issue as the DD gear shrinkage. (Apologies, I thought I had searched more than I had.) I'll give it a shot. Any insight on friction that gets worse when the unit is held with the cassette side up would still be appreciated. There have been videos in the past addressing similar issues, but they've all been removed.
Thanks for linking me to your thread from reddit: https://www.reddit.com/r/cassettecu...another_broken_wm20_restored_to_full_working/ I ran into this issue early last year when I was repairing a WM-10, well actually 3 of them. Anyway, after getting the special thin belts from mihokm on ebay/ https://fixyouraudio.com/, I was disappointed to find that they would get stuck every few rotations. Looking online, I could see youtube videos where people would "repair" the wm-10, but I could hear the gear skipping teeth, and the slight speed variations in the music they would demo. Examples (clunking and jerky supply): *Edit: For some reason when I link with a time stamp, the time stamp gets removed, so I have written timestamps above each video. Time: 9:11 Time: 1:35 (but you can hear the dull clunk through most of the video) Time: 0:52 (person looking at the gear through the window) It seems that the pinch roller is enough for some WM-10s to pull the supply reel past the missing teeth. I have come across some that seem to be working completely fine: I found the same issue as you, the ring gear around either the takeup (motorized) or supply platter has split. At first, I thought it was missing teeth, but I have since realized it is generally the same issues as with the WM-2's: A plastic bit shrinks around a metal bit, which causes the plastic bit to split. I do not know if storage conditions, manufacture plant (were there multiple?), plastic batches, or revision (?) make any difference. I think, just like the WM-2, every WM-10 (and similar variant) will eventually run into this issue. Solution ideas: I easily found the WM-2 epoxy/gear repair tutorials as you did and I marveled at how brilliant the solution was, but as I mentally stepped through applying this solution to the WM-10 gear, I couldn't help but note some roadblocks. 1. The gear is very difficult to remove if you don't disassemble the entire player. I am not sure if that little notch window at the bottom or access from the side with the cover off will provide enough room to accurate apply the epoxy. 2. This is an incredibly thin ring gear with only a tiny amount of surface area for the epoxy to bond to. 3. The opposite gear in which you need to mate/rotate against to get the correct gear profile is inaccessible when you have the platter on the spindle. Cleaning up any excess would be a nightmare and could cripple the device. 4. Admittedly this is a minor point, but adding teeth (which is what we are doing where the gear split) will cause the supply platter to rotate at a slightly slower (?) speed, which would raise(?) the tension the capstan/pinch roller applies to the tape? (But if it is the tried and true method with the WM-2 I suppose it must not be an issue.) Unless anyone has some great ideas, my next plan (if I ever get to get to it) is to cad model the gear, and have it SLA printed in glass-filled epoxy at 50 micron by a friend I know who has a Form 2 SLA. Lastly, here video I uploaded to youtube of me attempting to measure bits of it. I don't know if it is useful or not, but here it is. https://www.youtube.com/watch?v=ypWg2tkGE_o Also here are some pictures: https://imgur.com/a/ovNZxGD
Thanks so much for taking the time to post your experience. In case you didn't stumble over the PDFs of the full service manual and bulletins, here's the link: https://www.hifiengine.com/manual_library/sony/wm-10.shtml I'm not looking forward to taking this thing apart at all. Desoldering is one thing, but cracking the ribbon cable seems like a hard-to-avoid danger. I'm also worried about the pieces that aren't meant to be reused, like the washer on the capstan. I know I'll need to disassemble because of the friction beneath the Hysteresis plate, so I'll figure it out. It's just too bad we're thirty years too late to order replacement parts. I can see trying to stick a bit of epoxy into the gear through the opening and turning the gear, allowing the teeth from the other gear to create the proper indentations. The chances of it getting stuck back there are probably about 50/50. The difference in speed is probably minute with the epoxy repair, and you could always adjust it using with a speed calibration tape and the spot on the back. If you do print the gear, please keep me in mind. I'd be happy to pay for time and materials for a more permanent solution.
In the smuggest way possible, I'd like to ask you to take a look at that link you provided and tell me if there is anything peculiar about those service manual PDF links. As for your disassembly comment: I did have to heat up some flex ribbon so that it's adhesive would release, which was a pretty nerve wrecking experience. I do think to fix the takeup-side will require a full disassembly. (Come to think of it, I think one of mine did have the issue on the motor side as well.) I do think the epoxy through the gap would be incredibly convenient and quite the feat if you could pull it off. If I see any for-parts WM-10s I might pick one up just to have a parts/test player to experiment this method on. So far all the electronics in my others appear to work fine. With my concern about the extra teeth and rotation speed: The player is designed with incredibly specific gearing to give the correct amount of tension to the tape. Speed calibration is irrelevant since it is a closed system all being run by a single motor. (You can't adjust the speed of the individual gears.) With that said, I have thought a bit more on this topic: The supply and takeup reels are always rotating a different and constantly changing speeds due to the diameter of the spooled tape on each reel, so this means that the Sony engineers clearly had solved this issue. Therefore, I don't think an extra gear tooth or two will make a difference because it is self-regulating the tape tension in some way already. If I make any breakthroughs, progress or learn anything else, I will be sure to post it here!
Hey guys, thanks for your advice in this thread, I've found it difficult to find information about the WM-10 online. I recently picked up a WM-30 that shared the broken gear problem described here. It got to the point where the takeup spool would get stuck in the gap and stop spinning and the feed roller would continue to push tape through leading to a few chewed up tapes. I managed to solve my problem (and reduce the clicking noise somewhat) by using a blob of contact adhesive. I used a needle to push a small blob of the contact adhesive through the slot onto the gear, making sure it wasn't sticking to anything else. When dry, the contact adhesive is somewhat rubbery. This means that, although there are no actual teeth, the driving gear has something to push against, the reel continues to spin and the tape doesn't get stuck. It's not a perfect solution and I really think you'd struggle to do anything more exact through that gap but if your aim is to keep these in a working condition it suited me just fine.
KRJ, thanks for the advice! I actually just tore down my WM-10 this weekend and filled in the gear with epoxy to create new teeth. I'll also add new grease and oil based on the original repair manuals. I'm giving it until Wednesday to dry before attempting reassembly. I'm probably going to regret not seeing your suggestion sooner, because I'm not sure I'll be able to get this thing back together. Like you said, I think just having something to prevent the gear knocking is a great solution. If my epoxy patch doesn't hold, that will definitely be the next thing I try.
The epoxy worked like a charm. After sanding it down and reassembling, I had to scrape off a bit with a needle. Once I had that dialed in, the patch eliminated the knocking sound. But all the audio went missing as well. After some fooling around, everything realigned. I listened to Floating into the Night, and it was beautiful. Unfortunately, a new problem then developed. The tape started sliding off the pinch roller, causing it play too quickly and put wear on the tape. I'm pretty disappointed that I put in all this work, and my WM-10 only gave me an hour of tunes. If anyone has an easy solution, I'll try it.
Hello! At a risk at being criticized, I would like to share an alternative technique of such a repair. One that is rather counter-intuitive since it actually of involves breaking the gear even further. I discovered this technique from here https://escapements.wordpress.com/2011/07/15/sony-wm-d3-center-gear-fix/, so I will not discuss the details of the procedure and underlying logic. And yes, I have tried it as quite succesfully as well on a DD central gear. It is important to note, though, that the article dates back to before center gear replacements was available. And that remaking the teeth with epoxy in generally regarded as the right way to repair it in lieu of a replacement. In the case of the WM-10/20/30, though, a new replacement is not yet available. So I'm thinking this will be of more relevance. I've just repaired one. Being my own unit, I was willing to risk this technique. So I cut the gear at another place and nudge the whole section. Testing it multiple times against the matching gear and adjusting the position to where I feel almost no resistance in both cracks. The results are quite a satisfactory. Here is the finished gear: With regards to it's effectivity, I believe this will definitely never fully eliminate the knocking as a perfect epoxy repair will. But It's enough to make it only noticeable when putting the walkman against your ear.
when the crack is very wide that stops the movement parts from working this Technic can help to create a functional condition with DOUBLE click. This was discussed in the old forum.
I have a question about this problem: are the takeup and supply reels identical ? I thought about just swapping them around if that can be done, as the rewind function is not that critical. Given the design, it is clear that probably most of these units already have this crack (possibly on both reels), so what I propose would only be a temporary fix unless the other ring breaks. Note that I don't have a unit, just thinking if it's worth buying one for myself.
Hi, I just got a wm-20 with the same problem. Are there any guides / videos on disassembly to get to the gear? It looks a nightmare of ribbon cable, one of which seems soldered to the brass plate. Atm I think I'm more likely to break something else than get it out cleanly. If the answer is no, then I will try to bridge the break with epoxy and perhaps a short piece of donor gear. Thanks.
There is no guide available yet. I'll explain how it's done in text. As for how complicated it is, you pretty much need to fully disassemble the walkman for this repair. It may be possible to add the epoxy without complete disassembly, but you won't be able to file the excess. It is up to everyone to decide how they do it, but in my opinion a proper repair requires full disassembly, especially because this is not the only issue: motor also needs lubrication, both table reels' shafts should also be lubricated and so the idler wheel and capstan bearing. First of all, the reels are not identical they're completely different. They cannot be interchanged as an assembly: the takeup reel has an integrated clutch in it, while the supply one does not. The takeup reel also has a piece of copper for the auto-off function in FF/REW, not present on the supply reel. Supply reel and motor are a common assembly, hence the hole and shaft diameters are different (larger) than the takeup reel. It is very likely the gear ring will fit from one to the other, but there is a chance you will damage it while taking it out. In my opinion repairing the existing one with 2 component epoxy is the best solution. Ok, so let's take it step by step: 1. Remove the door, then remove the back cover: it's held on by 4 screws + the potentiometer knob (you can remove it with tweezers). 2. Remove the PCB, it's held on by 2 screws. 3. Remove the plastic washer that holds the capstan/flywheel assy in place and remove it. Then remove the holder (2 screws). 4. Remove the buttons assy, held on by 4 screws (2 short, 2 long and 2 plastic sleeves on the long ones). You need to move it around in a certain position for it to slide out. 5. Remove the DC-DC converter PCB cover. It's held by 2 screws. 6. Remove all the screws that hold the table reels/motor in place. There is a combination of screws and standouts. Note which one goes where. 7. Carefully remove both table reels, motor (including the 2 PCBs: DC-DC and servo), paying attention to the flex cable that is glued to the takeup reel assy. Do not remove the flex ! 8. Remove the washer that holds the takeup reel on the assy and remove the reel. 9. Clean everything well and apply the 2 component epoxy in the broken area of the gear. Let it harden a bit, but soft enough to make the imprint. 10. Take the buttons assy and make the imprint on the new tooth with the help of the driving gear: it is the middle gear between motor and flywheel. 11. Let it dry for a couple of hours. Then sand/file the excess material. 12. Re-assemble the walkman. I recommend taking apart the other reel, the motor, lubricate the motor bearing, the idler wheel and the capstan bushing. Pay attention that motor bearing is a ball bearing and you need to get oil inside the bearing only, not on the shaft or inside the inner part of bearing. This is explained in the service manual. Motors do get noisy on these so re-lubricating the bearing is highly recommended. NOTE 1: Pay attention tot he leaf contacts for auto-off function when re-installing the takeup reel in the assy. You need to spread these contact with a pair of tweezers before pushing the reel, otherwise they will bend. NOTE 2: I also tried the method of splitting the broken ring into more than one pieces. It does not work as the gap between teeth makes it very hard to engage with the driving gear. I tried with parts disassembled before commiting to it and came to the conclusion epoxy is the only solution.
