Head groove-o-mania

Here is a pictures of one head I have in a deck. Couldn't see dirt (or oxidation) without microscope. I don't want to judge if it is a little or much wear but there is definitely a dirt which I couldn't see without a microscope (couldn't get closer to a head). No way IPA can clean that head (I have tried). That head is gonna be lapped soon as I can't reach a seller to buy a new one. Waiting just a lapping film to arrive, lapping board is almost finished :)
Every single word @Skywavebe said about a heads, in another thread is nothing but the truth/fact.

S20220430_0013.jpgS20220430_0014.jpgS20220430_0015.jpgS20220430_0011.jpg
 
Alex SE said:
(13um is a sand paper 1500 which is equal to 12,5um actually)
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meaning that it's normal sand paper there and not lapping film?

a difference between sandpaper and that kind of lapping film is also the abrasive material of choice.

and, if the groove isn't much deep, you might also start from the 9um (with some more work than on the 13um) and then going down to the finer ones.
 
Determine the depth and start with paper of similar micron size to the wear depth, and from there, move up the chain to final polish.

Some use a standard routine regardless of the wear depth, but I think the depth should be identified (quantified) and start there, but not any coarser than that.

Do I don't lap heads but other things...
 
Makymak said:
I have seen that there is a custom among the cassette users community to condemn a head that has a groove. Ok, it's obvious that wear isn't favorable for the head performance but where is the limit? Not all the heads with wear are off. I have seen the groove accumulated on new heads after about 50 hours. I guess a 50-hours head isn't junk.

I don't want to start the debate "how many hours a cassette head lasts". My opinion is that nobody can give an accurate answer, not even an estimation. It depends on a number of factors.

It's a pity to discourage someone to buy a deck because "this head is crap". Unless some extremes, I think most heads out there have quite a lot of juice left. Even if lapping is needed, it worths it to prevent the decks with survivable heads reaching the landfill.

Edit: I don't try to sell any deck.
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You are right- too many experts out there that never even changed a head. I have heard of the fingernail condemning a head and I tell people that most people witth the fingernail test are idiots- I never do that as it tells you nothing. Most cassette deck heads have to be examined with magnification and with knowledge of how long a particular head is likely to last. I have changed many heads out when at Teac and other places including my own business- The alignment tapes or the record function will tell you if the head is shot or not. Most times except for Pioneer heads the lapping is a waste of time as it is with reel head 96% of the time. I have only done this now for 47 years so I have some experience. The fact is only the makers of the head have real longevity data and they don't even tell the public. Heads in the Tascam 112 last about a year- this is because this is the interval that I have had to change them. These were Church owned decks. The 112 uses a $14 heads so it will not last like the 122 Mk II.
 
...and one more thing: It's not difficult and complicated to do as it seems to be (except that you'll not gonna feel some fingers couple hours after). Now a head I was working with is one of those "softer" and took about one and a half hour to lapp, and some others can take double time, but its cool to do something new.

Tips: Paint a top side of a head with a permanent marker. Under lapping, if a paint is gone at the one side, but not at the other, that's the sign that you're not pushing a head at the right angle. When a pint is gone on both sides, that means that a head is flat and you can go over to next lapping film. Painting should be enough to do only once, before you start lapping.

Big thanx to Vince who convinced me to do that myself and all of you others who are sharing knowledge, experiences and opinions.
Just love this forum.
 
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So after fixing and adjusting everything on that deck, a second 965 is on the table. First things first, before making any adjustments is a head, cleaned with IPA. According to picture, first stop is lapping. Again.
Its has less wear than the first one, but still needs some love. Besides, there is even a much oxidation which have to be removed.
Deck2---head-before-lapping.jpg

Will be back with process pictures, as a last time.
 
Alex SE said:
And here is after. Some minor scratches but I don't think it will affect its functionality. Last lapping film used is 0,3um, didn't had 0,1 but that's OK I think. View attachment 72872
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even if they might be annoying to see, those hairline scratches don't really affect the performance and the tape will take care of them over time.

also, not a problem stopping with 0.3 micron film... it's just OK... if anything, playing a few cassettes will keep making a further gentle polishing... i would advice to use some oldschool pure chrome tape (i.e. BASF chrome from the 80's) for this task, which is a kind of harder oxide but also with a more plain surface, microscopically-wise... but if you don't have any pure chrome at hand then use any tape... in the end, the head will deal with whatever tapes while working.

for sure, the head now will work better than before! :D
 
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Little late (other projects running).

During my first ever lapping, I tried the head at every step. I started with a wet 400 silicone paper (very scratchy) and ended with a wet 2000. After the 1200, no difference in frequency response. It virtually restored the FR of the head. And the 1200 leaves the heads not shiny at all. After the 2000 I use polishing pastes (I have the whole 3M Perfect It series). It comes shiny but under angle you can see some hearlines. As Vince said, it's enough some 10-hours playback to mirror shine the contact area.

I know many people will question my method but it works like charm for me.
 
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