MCI JH 110 Series Reel to Reel

  • Thread starter Thread starter jortiz
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dodgeaspen said:
They would scare ME little. Head re lapping is not cheap.
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I could be wrong about them. Some heads are flat and some are round. I think head relapping is about $100 a head. I think that's about what I paid. On some decks the guides can be turned. It's the other stuff I wonder about. How do you test it out with out a pinch roller?
 
its in the heads

Those heads are very worn. very much like the lifters. I did not see a blown out gap but who knows how much head life is remaining. Here is a photo of a blown MCI playback head. Notice how the upper track shows a very distinct line and the lower does not. In looking at your heads (you are showing the record I think) look for a very fine line for the gap. If it is easy to see in places or all the way across then it is a bad head.

You can put sleeves on the lifters and rotate the guides. But a blown head needs to be replaced.

As far as re-lapping, You might want to try that yourself rather than spend any money on these heads. I'm guessing that these heads are down to 25% or less left. This is based on the width of the worn section vs the width of the side grooves. Notice on my head that the flat is the same as the side groove.

Regards, Ethan
 

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evm1024 said:
Those heads are very worn. very much like the lifters. I did not see a blown out gap but who knows how much head life is remaining. Here is a photo of a blown MCI playback head. Notice how the upper track shows a very distinct line and the lower does not. In looking at your heads (you are showing the record I think) look for a very fine line for the gap. If it is easy to see in places or all the way across then it is a bad head.

You can put sleeves on the lifters and rotate the guides. But a blown head needs to be replaced.

As far as re-lapping, You might want to try that yourself rather than spend any money on these heads. I'm guessing that these heads are down to 25% or less left. This is based on the width of the worn section vs the width of the side grooves. Notice on my head that the flat is the same as the side groove.

Regards, Ethan
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EDIT: I found out about re-lapping...........

Thanks for the response Ethan.....so where do I find the sleeves for the lifters? I did a search but didn't really see anything. I was under the impression that you had to get a professional to have it re-lapped. I didn't know you could do it/try it yourself. How do I go about that?

Best regards,

John
 
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jortiz said:
EDIT: I found out about re-lapping...........

Thanks for the response Ethan.....so where do I find the sleeves for the lifters? I did a search but didn't really see anything. I was under the impression that you had to get a professional to have it re-lapped. I didn't know you could do it/try it yourself. How do I go about that?

Best regards,

John
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I think Ethan meant you should "try" getting them re-lapped by a professional rather then buying new heads...at least I hope that's what he meant! :D

Cheers! :)
 
Nope...Ethan does his own using the Nortronics guide as a springboard. He put up a thread about it...relapped his 38 heads and got response out past 30kHz.

Plan on trying it myself at some point with his tutledge...I have a scrap 1" 8-track Ampex head that'll be good for practice...ultimately I'd like to do the heads on my BR-20T.

The man's an animal...
 
sweetbeats said:
Nope...Ethan does his own using the Nortronics guide as a springboard. He put up a thread about it...relapped his 38 heads and got response out past 30kHz.

Plan on trying it myself at some point with his tutledge...I have a scrap 1" 8-track Ampex head that'll be good for practice...ultimately I'd like to do the heads on my BR-20T.

The man's an animal...
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Aha!

I didn't see that thread originally! Kudos to Ethan for learning that art!

About the specs you mentioned him getting in repro, that was off of a calibration tape, yes? Not from what he recorded on the 38 itself!

Something else to note; as repro heads wear, the high frequency response is natural and normal to keep increasing, up until the point that the gap is completely gone, at which point you just end up with unbelievably horrible distortion. Record heads work in the opposite way, in that as they wear down, their high frequency response keeps dropping.

As one can see from that co-relationship, the frequency response of the same deck can remain fairly constant as the heads wear down evenly together but, the noise characteristics will slowly drift to the ugly side as the electronics limits get pushed further and further away from their tolerances with each progressive calibration to keep everything aligned.

Re-lapping is definitely cool and usable but nothing beats new heads and quiet supporting electronics.

Cheers! :)
 
That was a very interesting tidbit on the characteristics of headwear on repro and record heads -- did not know that :-)

I once tried to repair an MCI JH-110 which was housed at the Fire Station studio in San Marcos: https://homerecording.com/bbs/showthread.php?t=215732

I moved away and had to transfer to a different university, so never got to finish the project. I guess it's still unfinished :(

But I sincerely hope that the heads on this unit are serviceable, and that the guides can be rotated and if so, you may have a respectable machine with a new set of rollers, and a bit of cleaning up.
 
Hey guys,

Thanks for all the replies or posts. I've been away for a while. Sweetbeats, I did see the article on Nortronics, thanks for the link. I found a few other links on relapping. I read your post also Mukelroy. I've included two more pictures of the heads, although Ethan basically said my heads are pretty worn. At this point I'm not sure what I'm going to do. I'm cleaning it up still and still waiting for the eBay listing for the rollers to end. Ethan mentioned that I could get sleeves for the lifters. I haven't been able to locate information on this. Ethan-Can you help out with more information or someone else chime in. Thanks again for everyone's advice.

Headscropped2.jpg


Headscropped.jpg


004JPG2.jpg
 
Wag

I'm going to take a wag (wild ass guess) and say that based on these better photos of the heads that after a re-lap you will have between 30 and 40% left.

They are flat but would still work as is.

THere are a few questions:

Do you want to keep it and make it work?

How much do you want to spend?

Buying the rollers would put you into the good enough to test for functionality state.

A larger question is DO you want an MCIC or will a Tascam 32 fit your Half track needs. I'm not trying to talk you out of it. In fact I wouuld like to see you restore it. But if a 32 wold work you will end up spending less money for a 32 (or perhaps a BR-20).

If you do end up keeping it you can send the heads off for a relap
or perhaps we can work something out. Where are you located?

--Ethan
 
My MCI uses 1/8" OD lifters. Here is a link to some stainless tubing (for syringes) that is a good match to become sleeves. It is 0.156 OD qwith a wall thickness of 0.016 which gives an ID of 0.124". (0.156-2x0.016). Just might be able to heat it and slip it on. Or go for one with a 0.010" wall and use some silicone rubber to fix it in place.

http://eagletube.thomasnet.com/item...rd-fractional-tubing/s0156016t304sao?&seo=110

I'll have to give that a try. Some of the folks who work on MCI and Ampex offer quartz as well as stainless sleeves.

--Ethan
 
evm1024 said:
I'm going to take a wag (wild ass guess) and say that based on these better photos of the heads that after a re-lap you will have between 30 and 40% left.

They are flat but would still work as is.

THere are a few questions:

Do you want to keep it and make it work?

How much do you want to spend?

Buying the rollers would put you into the good enough to test for functionality state.

A larger question is DO you want an MCIC or will a Tascam 32 fit your Half track needs. I'm not trying to talk you out of it. In fact I wouuld like to see you restore it. But if a 32 wold work you will end up spending less money for a 32 (or perhaps a BR-20).

If you do end up keeping it you can send the heads off for a relap
or perhaps we can work something out. Where are you located?

--Ethan
Click to expand...

Ethan,

Thanks for the reply. Yes I do want to keep it. I actually have a a 34 that works great, but always being into gear, I couldn't help but pick this one up. I'm not wanting to make this a money pit although things add up quickly when you're buying things here and there.

I live in Everett, Washington- so kind of opposite ends of the state but if you are offerring to help I could make the drive somehow. If you're offerring to help with relapping the heads for me I would appreciate it. I'll send you a PM?

Thanks again Ethan for all your advice and help. And also to you other folks that have responded to my posts!

Best regards,
John
 
jortiz said:
Ethan,

Thanks for the reply. Yes I do want to keep it. I actually have a a 34 that works great, but always being into gear, I couldn't help but pick this one up. I'm not wanting to make this a money pit although things add up quickly when you're buying things here and there.

I live in Everett, Washington- so kind of opposite ends of the state but if you are offerring to help I could make the drive somehow. If you're offerring to help with relapping the heads for me I would appreciate it. I'll send you a PM?

Thanks again Ethan for all your advice and help. And also to you other folks that have responded to my posts!

Best regards,
John
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Hi John,

Cool that you are in WA state. My Dad lives in Concrete so I get through Everett a few times a year.

OK wanting to keep it sets the stage.....

If you want to pop your headstack in the mail I'll give relapping a try. I was going to do the headstack on my JH sometime soon and doing 2 sets is not that much work extra. I'm no expert....

--Ethan
 
Okay, I'm still waiting for the rollers I got from eBay so I haven't really done anything new to it, except put in new VU meter lights. I have ordered a manual for it also and a head wiring harness for the one side that got spliced for whatever reason. Still going over and over the insides as much as I can. It's really just a waiting game. One thing that has been on my mind is that of the stop mechanism on this machine. Everytime I power it up and run the reels the take up reel side just keeps on spinning for quite a while. I basically just stop it with my hand. The supply side stops real good but the take up side doesn't stop for a while. I don't have tape on it (obviously!) but I'm wondering if it's something I need to work on before I get the rollers. Shouldn't the take up side be stopping also? What do I need to look at for this? Man I wish I had the manual and of course the rollers! Ugh! Could someone please comment on this. Thanks for any advice.

Best regards,

John
 
Hi John,

There are a number of adjustments that you will be able to make later. My deck also turns a little. The test will be with tape on the reels where the two reels servos will work together to supply constant tension. Hang in there till the rollers come.

On a side note. I just ordered some stainless steel sleeves. If they work out there is enough to share. :)

--Ethan
 
I got the rollers today for this unit. I put them on and some tape. Hit the play button and there is kind of a whiny/squealing noise coming out. It's not the tape but seems to be from the flywheel or the rollers or something. The reels aren't in contact with the cabinet. I really wasn't getting that before. Anyways....without no XLR cables connected I got some meter movement from the right channel, nothing on the left. I then put the cable on and then the needle didn't move at all on either the left or right. When I unplugged the cable once again I got some meter movement. Previously I had cleaned and dexoited it and checked connections. So this was the first test with the rollers and tape. The rollers were in good shape BTW. So now I'm not sure what to do except go over the connections again. I'm still waiting for the wiring to the head stack as the one that was there (as shown in the pictures) was spliced on the one side. Funny thing was that I'm getting the signal from the wire that was spliced and not the "normal" one. I've also ordered the manual and am waiting for that also. Any suggestions on what to do next? Thanks for helping out.

Best regards,

John
 
UPDATE. Okay I was able to get one channel working on this machine. I plugged in both cables of the outputs to my mixer, the Tascam M520, and it was through pretty good. But now the other channel? Guess I have to tear apart that side and see if I can figure out what's going on. I'm then going to try to record on it. Boy when I get this figured out I'm going to be a happy camper. :) More later. Back to work.

Best regards,

John
 
Do you have the service manual to this? If not, the service manual has highly specific, detailed instructions on calibrating the transport functions. (offset null, tension, braking, etc.) Should help w/ squealing sounds and give you proper tape tension.
 
Muckelroy said:
Do you have the service manual to this? If not, the service manual has highly specific, detailed instructions on calibrating the transport functions. (offset null, tension, braking, etc.) Should help w/ squealing sounds and give you proper tape tension.
Click to expand...

Mukelroy-Thanks for the reply. I have the manual coming from Blevin's, it just hasn't arrived yet. Yeah, once I get that I should have a better understanding of things. The noise kind of died out.

I actually got it working for playback now for both channels. So I'm in business on that side of the problem. I made some progress on the recording side of things. It would show some movement on one channel but not on the other. I tinkered around on it and now have both channels showing movement. I won't go into too much detail with stuff. Anyways, when I did try to playback what I had recorded it only showed on one channel. I'm happy to be making progress as nothing was going on for a while. Can't wait to get the manual and the wiring harness as I think that is why the one channel is working? (the one that was spliced.) We'll see.

Best regards,

John
 
There are some pdf of of manual chapters that you can download till you get you hardcopy. AnalogRules is the first place to start.

For many problems just cleaning the pins and connectors on the motherboard to card will clear up many things.

I'd like to see you Blevins manual sometime. Been thinking about buying one.... For a year.

--Ethan
 
evm1024 said:
There are some pdf of of manual chapters that you can download till you get you hardcopy. AnalogRules is the first place to start.

For many problems just cleaning the pins and connectors on the motherboard to card will clear up many things.

I'd like to see you Blevins manual sometime. Been thinking about buying one.... For a year.

--Ethan
Click to expand...

Ethan,

Thanks for the response. Yeah, cleaning and cleaning and........soldering and soldering and.........I must be really sick as I'm rather enjoying myself or having fun......I guess because of the satisfaction of getting something to work. :):):eek::D

The manual......yeah, can't wait to get it and find out more about this. It's one thing to just dive into something with help from everyone here or the internet but having something to look at to make some better sense of it should make things easier. I'd be more than happy for you to look at it. I didn't know if you had one or not. I could make a copy for you at some point. How would that work for you?

Thanks again,

John
 
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