Did some Studer work today. Nothing major, but trying to get stuff out of the way as far as the spinning motor.

I didn’t mention it before, but a few ICs on the logic board have this really weird coating/oxidation. It didn’t come off easily with alcohol or DeoxIT, and I’m not even sure it was oxidation, but my French friend who’s a Studer wiz suggested to get a fiberglass pen to remove this stuff. It totally worked! Here are two chips next to each other, one before I cleaned it with this pen, and one after:

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The lighting in this picture is bad, but you can tell the difference.

I cleaned the legs off with alcohol, and got a few drops of DeoxIT in the sockets and moved the ICs in the sockets. That should take care of any oxidation.

I also replaced the stop button’s bulb, not that it makes any difference, but I thought I’d follow up on it.

Anyway, turn on the machine and the takeup motor is spinning out of control again. The stop button doesn’t light up and that is really grinding my gears. It seems like the right voltage is feeding into it (~27V).  I don’t know if this is related to the motor spinning. I’m pretty sure the stop button was lighting up before. Haven’t tried a different bulb yet.

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Jaguarillo gets new pickups and setup

This guitar is a friend of a friend’s. I worked on his acoustic before and I guess he was happy enough with it to come back. Sweet!

Jaguarillos are Jaguars but with two strat pickups and a humbucker in the bridge. The guy wanted to change the pickguard, and replace all the pickups – Novak lipsticks in the neck and middle position, and a Manlius Stud-Bucker in the bridge.

The pickguard needed some work because the humbucker wouldn’t fit. The radii of the corners were too big:

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I already started working on it when I took this picture, see the bottom left corner.

I did the whole thing with files (Nicholson Handy File and a round file) and a razor blade turned scraper. It came out ok (forgot to take a picture), but not my best work. It would have been much easier to do with a router.

The rest of it was straightforward, except that when I put it all together I noticed that the tremolo clicks when actuated. This is a thing with the cheap, import tailpieces, and it can be avoided depending on how high or low the tremolo arm is set up. However, the owner of this guitar wanted me to set up the lock so the guitar can stay in tune if a string breaks, so I had to go in and start filing.

Mike & Mike Guitar Bar posted about this before, so that’s where I got the idea. You can read what else they wrote about import tailpieces here. Basically, I filed every surface so it is flat. I think that at the very least the molding marks should be knocked off, but if the plate is off the tailpiece and you’re filing, might as well go the extra mile.

There was one little problem that is worth mentioning – the Stud-bucker had only two leads – hot and shield. So the middle+bridge position were out of phase, and flipping the leads couldn’t fix it. The reason it couldn’t be fixed is because then the shield (and pickup casing) are hot, but the rest of the metal parts (and strings) of the guitar are ground. Then if the player touches both the pickup casing and the strings, or bridge, or any other metal parts, the signal will short. FWIW, Manlius offers these (and I assume all humbuckers) with coil taps, so the polarity of the pickup can be flipped. Here are a few pictures I took after it was finished:

J Mascis Jazzmaster rewire + goldfoil at the bridge!

This is my friend’s Jazzmaster. He asked me to install a Curtis Novak Goldfoil at the bridge, and rewire the guitar for two separate volumes and tones (using the rhythm circuit for the tones), and a kill switch.

I used this schematic, credit goes to Sigler Music Center in Arkansas:

JM two vol two tone kill sw

What I did differently is that I used linear pots for the volumes and log for the tones, and the kill switch is on (signal passing through) when it’s at the bottom. The switch being on when it’s at the bottom makes more sense because the player is more likely to hit it strumming down. Also, that’s what my friend asked for.

Without strings on, I thought there was too much of a hum in the middle position. I say too much because my setup here isn’t the quietest, being so close to the train and all. That made me think that the goldfoil’s magnet isn’t oriented so that its north faces the opposite direction than the neck pickup’s north. In other words, the neck pup and goldfoil aren’t RWRP.  However, the original bridge and neck pickups measure very close – 100 ohms different, with the bridge being the hotter one, of course. I told my friend about it and we decided to use the Mascis bridge pickup in the neck position. I put strings on it, and no hum.

I haven’t had a chance to really play through an amp and see how I like the volume pots being linear and the tones being logarithmic (it was too late when I was done), so I moved on to non-amplified setup. Basically, the low E string was slipping out of its saddle, and the radius of the bridge (TOM) didn’t fit the radius of the fretboard (9.5″), so I had to file the saddles a little bit.

This guitar is almost done, just need to hear it amplified.