1961 Hofner 172(l) Restoration Project

[drathbun]

I rewound the second pickup using more tension and filled the bobbin as full as it would go and got 4.68 ohms out of it.

I haven't potted them yet but I hooked them up to the control panel. They seem to work fine. Lots of snap, very trebbly.

However, I'm getting huge hum when I touch the pickup covers. I soldered the covers back to the base plate and the wiring is correct based on the diagram the previous owner sent me.

However, this control wiring looks odd to me. The pickup ground wires are soldered to the ground lugs of the switch next to the pot. And, there is a small wire running across all the ground lugs of the switches (at the bottom of the center switches in the photo below). Seems to be a LOT of wires running to ground and I suspect that is the cause of the ground loop. But the Hofner wiring is strange to me.

Any Hofner experts out there? Does this look normal? Why are the resistors wired through the grounds?

[drathbun]

I've rewound both pickups. I just couldn't get enough wraps on the bobbin to get a good amount of resistance. I was hoping for ~ 7.5 ohms but ended up with around 4.5 ohms. I put them back in their covers, hooked them up and put the neck on the guitar and strung it up. The pickups work fine. They are quite snappy. I'm getting a lot of hum so I've been trouble shooting the electronics with help from people at the Hofner Forum.

In my order of products from Stew-Mac, I purchased a new for the Hofner. The 172 has a tremelo and the delrin nut is very slippery which will keep the guitar in tune with the whammy bar and keep the nut from pinching.

I first removed the old nut which had a piece snapped off. I on the side of the nut with an exacto knife so it wouldn't pull wood with it. Then I with my pliers. After cleaning out the nut slot, on the new blank. Then I it as best I could with a combination of my dremel tool and dragging it on some sandpaper. I marked the position of the strings and will use my to create the new nut slots.

Today I decided to pot the pickups. I tried doing it in slowcooker but that was too... ummm... slow! So I put the combination wax in a small tin and put that in boiling water on the stove. I measured out 75 grams of parafin and 20 grams of pure beeswax (I bought it on ebay from a beekeeper in Ontario!). It heated to about 160F. I turned the stove off and mixed the wax up until it clarified. It stayed hot for quite a while. I decided not to remove the pickups from the control and just dangled them in the wax from their lead wires. I gave them about 5 minutes each, then cleaned up the excess with paper towel while it was still liquid.

[Spud1950]

[drathbun]

[drathbun]

Ok Spud! You are DA MAN! I never would have suspected reversed wiring at the output jack. I assumed it was wired correctly and hunted all through the circuit piece by piece with no luck.

I just now flipped the output jack wires over and voila! NO HUM!

On a Switchcraft jack it is obvious which is tip/hot and which is sleeve/ground. On this Hofner output jack it is not so obvious. In fact, upon close examination, I couldn't determine which was which until I put my meter on it.

Thank you so much! Now on to the neck angle... which is Baaaaaad!

[drathbun]

The guitar is almost complete. I removed the truss rod nut, oiled it, gave it a crank and put the neck back on. It has just a slight bit of relief but the action is still very high.

I'm toying with the idea of putting in a micro-tilt neck adjustment rather than simply shimming the neck. This is not a 1950's strat so I can't say that I'm ruining its resale or vintage status. So why not? I just love the microtilt on my AMDLX Strat.

Has anyone made a home-made micro-tilt neck adjuster for a bolt on neck? Any suggestions?

[drathbun]

Tonight I cut the new delrin nut, shimmed the neck and set the action at the bridge.

First I marked the string locations on the old nut by transferring them to an I started each slot with the , then used my digital caliper to measure from the bottom to the highest slot on the old nut and until I got it close enough to adjust with the nut files. was very tall and had some very deep nut slots as a result.

Then I FACE (not the bottom of the nut) with some medium viscosity cyanoacrylate glue and put the neck back on the guitar. Since the neck angle was still too deep, I put a small piece of old credit card plastic (0.30 thickness) at the heel of the neck pocket first. I restrung the guitar and tuned to pitch. I checked the action of each string at the first fret after fretting the string at the third, pulled the string out (with the aid of a dive bomb on the trem bar) and filed the nut slots so I had just a hair clearance.

Then I raised the bridge to give me about 5/64" clearance at the 12th fret, tuned again and it plays like a dream. It buzzes mid-neck on the low E so I might introduce a little more relief with the truss rod when i take the neck off to replace the shim with some hardwood.

Guitar = $75
Nut = $5.35
Coil Wire = $38.64
Tuner bushings = $3.00
Teacup Knobs (on order) = $40

Experience = priceless

[Spud1950]

Excellent! I really enjoyed seeing your project come together and I'm happy that my suggestion as to the jack wiring did the trick. It's a really common snafu that comes up very often on guitar forums. I'd really like to hear how your rewound pickups sound!

[johnnyb]

that was great to watch your progress. congrats and thanks. i would also like to hear the sound it makes.

john

[drathbun]

Ok. I just grabbed the guitar and plunked out a couple of riffs on it.

The first segment is with the bass pickup engaged and is slow fingerstyle on "Sun King". The second is some fast strumming with the treble pickup engaged on "Sultans of Swing". The end part of Sultans is the same pickup but played with my fingers rather than a pick.



I'm plugged directly into a Line6 Spider II 115 amp on the clean setting with a touch of reverb. The amp is mic'd about 1.5' feet away with an Apex 435 large diaphram condenser microphone into my MAudio sound card and recorded in Sonar 8. I saved it to WAV and then converted to MP3.

I'm still getting some hum when I have the "Rhythm" switch engaged that goes away when I touch the pickup covers or the metal cord plug.

[Spud1950]

Pickups sound great. Really nice clean,ringing tones.

[drathbun]