I do this as well, more as a hobby today, but 40 years of repairing electronics and broadcast equipment. While I do like videos like this, I want to caution people that REALLY try to circumvent paying a GOOD technician to fix their deck to NOT try lapping their own heads. Especially ebay flippers..... You just know someone will, and then when it's ruined.... THEN expect a tech to perform some sort of miracle for them.... CHEAP, of course. I speak from experience on that point. 😉 Of course, they SWEAR on a stack of bibles they never touched it! Lapping is an art, and I find it meditative as well. I enjoy doing it, but as you can see, it takes time and a lot of practice.
This is so true. It's a big reason why I often make the point that I'm not doing the RU-vid tutorial thing, or giving anyone a diploma from RU-vid U. I'm just showing what to expect when a machine is sent to me for overhaul, I purposely avoid tutorial style language. This stuff isn't easy, it takes years of practice, following the screwing up of the first dozen jobs. I do some type of lapping in the shop daily, including carbide, and know how to get a flat-mirror finish even on it. Still, I can't fault anyone for wanting to try. It keeps the skill alive, and a few will take to it and become proficient. A few of those will advance to become better than us, that's my hope anyway. The majority, as you said, will ruin theirs. Your warning is worth a pin. Thank you for that.
Очень кропотливый труд, Peter! Такой труд под силу, только тому человеку, который очень сильно любит свою работу! Спасибо большое за видео! И кстати, микроскоп у вас очень хороший!👍👌
Having lapped a lot of reel deck heads I have never tried cassette. You demonstrate the reasons why I have never tried. Special equipment abounds. Damn good work sir.
There aren’t enough videos on RU-vid about tape head lapping, especially for cassette deck heads. This is so great to see. You’ve developed some excellent precision and technique! I have been wanting to learn how to lap heads so I can keep my collection of decks operating at spec for as many years/decades as possible. I already acquired plate glass and 3M lapping film a year ago but just been too hesitant to start lapping with it. All the crazy work required around the tape guide is what I’m afraid of. I wish so badly it could be an optional part that could be removed and never reinstalled! I always wondered about bending it… thanks for proving that it should never be bent, so I don’t have to make that mistake ever.
Thank you for watching and for your comments. Not everyone has the necessary equipment, it's a fastidious job to be sure. I'm just showing how it's done in my particular shop when a client sends a deck to me. Often, an aggressive polishing will suffice if the wear isn't such that the tape is curling into the edges of the head. When it gets to that point however, a lapping or replacement is the best resolution.
One other thing I learned from this video was the method of applying anti-corrosive on heads that sit in storage. Is there a particular brand you buy for that? And, how is it removed from the head at a later time? Is IPA good enough?
I watch with great curiosity. Serious challenge. If the head gap is not parallel, then after grinding it will lose the upper part of the band. Oglądam z ogromnym zaciekawieniem. Poważne wyzwanie. Jeżeli szczelina głowicy nie jest równoległa, to po szlifowaniu straci górną część pasma.
The heads are usually off by a little, most have enough material to bring them back into uniformity, but not always. Some can't be lapped at all, some look good until the gap is examined and the discrepancy discovered. It can be an unknown until the lapping is completed and the gap examined.
thanks for the review. useful information... an observant person will always see useful information for himself if possible, I would like to see methods for working with heads GX...and find out your recommendations, sir
Thank you for watching and for your comments. For any of the glass heads, the methodology remains the same, but I substitute diamond abrasive in place of the aluminum oxide.
Hi Peter, as i watch I'll put in a few comments if I may ... 1) Those heads were quite well made, look at the relative consistent gap between the channels. I've seen worse. 2) The circuit board behind the head is a very good idea - should stop excessive soldering from possibly fusing any internal windings, 3) My view currently held view on head guides is that - they don't truly 'guide' the tape. That ultimately must be done by the cassette tape shell rollers and trueness of the capstan/pinch roller system. 4) You did a fine job on lapping and aligning those guides Peter, better than set at the factory I suspect! I admire you precise methodology. I'm no expert when it comes to lapping heads, I have done a few, but I too only allowed one 'pass', and then I moved across the fine grit paper. I think I started out at 3000 grit, can't recall now. Very interesting to see what you did, and I appreciate the time you will have put into making this. Eric. (Edited x 3)
1 - I view the gap as very consistent also. 2 - Agreed, isolating the windings from the leads is a good thing. 3 - Agreed again, we spoke about this in another thread, I quoted some text from a Denon manual that was sitting on my bench, stating exactly that. 4 - Thank you, I'm certain the factory has very accurate fixtures as well, but giving .010" tolerance to a production shop, sometimes can be like giving whiskey and the car keys to your teenage son. That's the reason tightening up all these individual tolerances during a rebuild, can result in a machine that will better its own specs by quite a lot on occasion. We used to call it "blueprinting" in engine work, maybe we still do? There's nothing wrong with a single pass if it results in the desired outcome. I also needed to correct the flat spots and return the profile to the factory radius, so it took a bit more work. There isn't much downward force applied in the finer grits, it's almost like stropping a razor. Thanks again for watching and for your ever thoughtful comments.
@asbcustom, considering that you agree with Jame's #3 comment, what do you think would be the result if you never reinstalled the tape guide after removal? With a good pinch roller, is the guide needed at all? I suspect that it could still assist with poorly designed cassette shells that may skew the tape and may only be needed for single capstan decks, if any. And another thought, what if the deck is dual capstan like a TEAC V-970X? I have this TEAC deck, and it uses the same head as the Tascam 122 MKII. I wonder if the guide is not needed since the tape already has intercapstan tension to straighten it out, plus a guide on the supply roller.
@@stereosteveooo I have no doubt that if everything in the transport was clean, in spec., and in top condition, and using a high quality shell with perfectly aligned leaders that exhibit no excessive run out, the tape would indeed track correctly and maintain acceptable azimuth on that particular tape, or that run of tape. If however, when anything falls out of spec., be it debris, wear, or whatever else, I think the guides act as guard rails to re-center the tracking when necessary. Additionally, during entrance and exit, I believe they help center the tape immediately upon head contact, rather than it needing to momentarily work its way in to alignment, while the back tension, pinch roller pressure, take up torque, and planets all align, to start the tracking process. There's a whole lot of physics happening when that headstack moves into position, and the mechanical precision needed to time it all it at that level of precision, would be prohibitive to implement, and then once it was, needing to rely on all the shell manufacturers to be just as precise with their product. Better to just use a tiny steel stamping and get the machines out the door at a price we can afford.
@@stereosteveooo The cassette was never meant to be a HiFi medium back in the early 1960s, but if so - it would have had to have been designed better! Manufacturers later did all they could to make the system more stable - dual capstan is a good example. Ultimately and IMO, the cassette shell guides are responsible for guiding the tape. So we should buy good tapes in good shells etc. A head guide on its own would simplly mangle up the tape as the incoming tape would in time ride up and down the head guide. I've experimented in a limited capacity with a well aligned dual-capstan deck like the TC-161SD without a guide - no problems. I suppose there would have been some exceptional circumstance when this doesn't work, ie when the tape prior to loading is very very slack.
@@JamesE707 Eric, it would be interesting to run multiple cycles with tapes of differing quality levels. I once did something similar with an azimuth test tape - removing and reinserting, closing the tape door with inconsistent aggressivity, flexing the chassis, etc. Everything in the world is made of assorted viscosities of rubber, everything flexes, no matter how stiff it might appear to be.
Thank you for watching. Microscope is old-school Nikon Optiphot set up for metallurgy, and from 50x-400x. Head profiles are confirmed on an optical comparator and shown at this point in the video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ApgL5WCFwmw.htmlsi=-79So1naAFAf2FPW&t=3854
hi sir. I have a Tascam mkll and it never plays more than half of the cassette. To stop. sometimes it feels like a bit of wow. Is it possible to send it for repair?
Another Great Video I Have a Pioneer Ferrite Erases Head which looked to be in bad shape I removed it since it effected the tape path and I Polished it a lot which removed the brown crud on it and also file the edges which were really sharp . looks almost shiny now.. Can I do a down and dirty Re-lapping it, since its not that critical. w maybe normal sandpaper? Thanks
Thank you. I would strongly advise against using normal sandpaper on the erase head, or anywhere else in the tape path. The erase head needs the same high polish as the others. Lapping film is not at all expensive and can be purchased online, even through eBay. A poor quality finish can strip the oxide layer off in a hurry, and also affects the ability of the gap to do its job. It's really important to be studious and deliberate around any tape head.
@@asbcustom Ok Thanks good to known, maybe your next video a Erase head did not see any Videos on youtube , I will have to buy some Lapping film and that polish in this video. It would be a good one to start w I'm guessing its has a thinker layer than the R/P head?
