Vintage Hofner 173 Reboot | Part Five

Part One | Part Two | Part Three | Part Four | Part Five

Photo Shoot

This post concludes the series on the Vintage Hofner 173 Reboot. You might also like to check out my earlier posts on the guitar's original External Features, Hardware; and Electronics. In Rebuilding the 173, we went through a detailed account on what had to be done to get this 173 back to playing condition. 

Mind you, I could not call this a proper restoration as the only original parts retained were the neck, body, bridge; and vibrato unit. Well folks, let's look at some before/after pics, then. And, kindly give the audio clip I've uploaded to YouTube a listen. Thanks in advance, and God bless :)

Vintage Hofner 173 Reboot | Part 4

Part 1 | Part 2 | Part 3 | Part 4 | Part 5 

Rebuilding the 173

Way back in September of last year I received a vintage Sunburst Hofner 173 electric guitar from Sheikh Danial; a guitar enthusiast. It belongs to his retired-musician Dad, and as such; has enormous sentimental value to both father and son. However, it had been stowed away for years and fallen into decay. In short, it was totally unplayable.

If you'd like to refresh your memory, do check out my earlier posts on this guitar's External Features, Hardware; and Electronics. There was certainly a lot to be repaired and/or replaced, and countless obstacles to be overcome before this guitar could be plugged into an amp again. I'm calling this job a "reboot" because I did not manage to restore the 173 to its original specs; but only worked on it until it was back in playable condition.

Right off the bat it was decided that a new set of tuners needed to be installed; preferably with "tulip-style" buttons. We managed to score a 6-in-line set from Musiclily, but as expected; they would not fit into the existing 6mm tuner holes. So out came the reamer, problem solved. The old tuner holes were plugged, and new ones drilled to accommodate the Musiclilys. And of course, I did not forget to clean the rosewood fretboard, recondition it with lemon oil; and degrime/polish the frets.

Among other issues that were discussed and resolved included replacing the pickups with new mini-humbuckers, the slide switches with NKK M-2022 on/off toggles, the pots with Alpha A500Ks; and the output jack with a Neutrik/Rean NYS229. The original German "Pekalit 15270" skirted knobs would also be replaced as the set screws had disintegrated; amongst other reasons.

The neck had to be removed for neck pitch adjustment. To do that, the neck screws and neck plate needed to be removed; of course. I discovered to my dismay that the screws were frozen in place. The most practical solution was to shear off the screw heads, remove the neck plate; and drill around the screw shafts with a hollow punch bit. Easier said than done, for even after getting the neck free from the body; the screws were still frozen in the neck heel. 

So another round of drilling with the hollow punch bit ensued; and the screws were finally removed from the neck heel. Following this, the holes in the neck pocket and heel were plugged, and the plugs trimmed flush. After carefully redrilling the neck screw holes, a test-fitting was carried out with a new neck plate and screws; and everything fit together nicely.

Much earlier on, the warped pickguard had been removed after a lot of trouble. Many of the tiny pickguard screws had lost their heads, so to speak. They were immobile, so what was left of their heads were sheared off with a drill. Once removed, a hollow drill punch bit was used to create plugs around each embedded screw shaft; and these plugs pried out. The resulting holes were then plugged with wooden dowels; and the plugs trimmed flush with the body.

I'd planned to re-use the pickguard after flattening it out, but it was not to be. One night, I soaked the pickguard in hot water for a few hours, weighed down by bricks; but it was of no use. So out came the heat gun. I was using the heat gun on its low setting when the pickguard suddenly started emitting thick clouds of pungent smoke. Spontaneous combustion, perhaps? 

There were no flames, just smoke that made it hard to breathe and my eyes water. A fire extinguisher did nothing to quell the smoke, so out I ran from my workroom. The wife and cats were totally shocked, to say the least. Upon re-entering the room the next afternoon, most of the smoke had cleared, leaving behind a lingering sickening odor.

I looked at the pickguard, and my heart sank. All that was left was a pile of ashes and bits of plastic. I scooped up what was left of it and carefully sealed it in a plastic bag. I knew I had to show what was left of the pickguard to Danial and his Dad when they next dropped by; and the mere thought of doing so filled me with dread. That was it, then; I'd have to fashion a new pickguard from scratch.

First, clear plastic, marker pens and French Curves were used to trace the outline of the old pickguard as accurately as possible. Then, this outline was transferred to a piece of thick cardboard to create a template of the actual pickguard. Holes were drilled to accommodate the pots, switches and jack; while rectangular sections were cut out to house the new mini-humbuckers. Once the template was ready, the electronics were temporarily installed for a test fitting. Thankfully, the fit was good, so we were ready to move on to the next step.

The next step involved removing the electronics and affixing the cardboard template to a piece of three-ply black/white/black with double-sided tape. Then came the really hard part, cutting out the actual pickguard. Lots of tools were used, including coping saws, files, abrasive paper, plastic cutters; and even Forstner drill bits. Holes for the pickguard screws were then drilled. I decided not to use replacements as tiny as the original ones, and chose instead to go with countersunk standard-sized 1/2" screws. I believe that these would do a much better job of keeping the pickguard in place.

With the new pickguard all raring to go, aluminum foil was glued to the back for shielding purposes, and the electronics reinstalled and wired in. This was possible because all the electronics, including the output jack; were located on the pickguard itself. All that was left to do would be to run a ground wire from the base plate of the vibrato unit and solder it to the back of one of the pots.

There was a still some more work to be done, though. The plywood body was in poor shape, and had started to delaminate in several places. To make matters worse, a lot of unsightly grime and crud was still embedded in the original lacquer; despite my best efforts to remove them. The only way out would be to address the delamination issue, fill and seal the body, sand everything down; and spray a couple coats of clear. 

Meanwhile, hardware that was to be retained, namely the bridge and vibrato unit; needed to be derusted, cleaned and polished as best as could be. The most challenging task was cleaning the vibrato unit's base plate; which was encrusted with rust and corrosion. Seriously, I had to break out my random orbital sander to get the job done.

In the end, the whole guitar was put together, strung with Ernie Ball Regular Slinkys; and set up as best I could. The final string action was a tad higher than I'd have liked, unfortunately. It was those tiny low frets and 12" fretboard radius, see. A full refret with medium-jumbos would've allowed for a much more comfortable action; but doing so would have blown the budget right out of the water.

This guitar features seven pickup combinations: 

01.    Neck Only

02.    Neck/Middle

03.    Middle Only

04.    Middle/Bridge

05.    Bridge Only

06.    Neck/Bridge

07.    Neck/Middle/Bridge

Curious to find out what this rebooted Hofner 173 sounds like? If you are, do head on down to YouTube and give the audio clip I've uploaded a listen. Part Five will feature a couple before/after pics, a photoshoot of sorts; one could say. Thanks for dropping by, as always; it's deeply appreciated. Meanwhile, stay home, stay safe; and God bless :)

Vintage Greco Solidbody - No Serial Number

November 3, 2023 Update
According to a reader, this guitar is in fact an "... EGC made by Cort in Korea post 1989," and "not a 1975 Gneco." I thank this kind individual for dropping by and sharing his/her opinion on the matter. 

December 12, 2020 Post

Restoring a Greco EG550B earlier this year was an educational experience; to say the least. I never thought that I'd be working on another Greco quite so soon. Yes, this one also resembles a Les Paul Custom. However, it differs from the EG550B in that it has a regular set-in neck and top hat knobs.

Perhaps the most intriguing feature is that it lacks a serial number on the back of the headstock. Interestingly, Vintage Japan Guitars affirms that Greco only started issuing serial numbers in 1975. Therefore, one can safely assume that this black beauty was manufactured before 1975.

This Greco came in for a thorough electronics check because i) only the neck pickup was active in all three switch positions; and ii) none of the controls worked. A quick check with a multimeter revealed that the bridge pickup was indeed functioning. However, the hot and ground leads from both humbuckers were wired directly to their respective tone pots.

Gotta admit that this was the first time I'd ever come across such a wiring scheme. One usually wires each pickup to its volume pot, and then takes the signal off the input lug to the tone pot. Meanwhile, the signal from the output lug of each volume pot goes to the three-way toggle switch; and out to the output jack.

The wiring was in such an unwieldy mess that I did not bother trying to figure it out. I simply desoldered everything and did a full rewire. The tiny pots, which I suspect were not the factory originals; were dumped in favor of full-sized Alpha A500K Long Shafts. The toggle switch and output jack were serviced and reused as they were still in good condition. Thankfully, the guitar sounded as it should after rewiring. Here's a SoundCloud audio file of the rewired Greco through my little 'ole Ross G515 MiniMouth amp.

It's a beautiful instrument, no doubt. Amongst its impressive appointments are gold hardware, "Greco Guitar" tuners, abalone headstock inlay, five-ply headstock binding, seven-ply body binding, bound ebony fretboard; and mother of pearl fretboard inlays. I don't think they're mother of toilet seat. Nah, Japanese guitar makers were dead set on outdoing Gibson at their own game in those days. So, I don't think they'd go for fake MOP. What do you think?

 

Vintage Hofner 173 Reboot | Part 3

Part 1 | Part 2 | Part 3 | Part 4 | Part 5

Electronics

So far, we've looked at the External Features and Hardware of this vintage sunburst Hofner 173 electric guitar. Now it's time to evaluate the electronics. Underneath the pickguard lies a maze of cruddy wiring, which takes quite a while to figure out. 

I'm glad to say that I've finally determined what's connected to what; and what it is that I'm looking at. And if you click the last picture of this post, you'll see a circuit diagram of sorts; courtesy of yours truly and MS Paint.

The set up is basically three H513 single-coil pickups wired to a trio of DPDT ON/OFF slide switches. Up is OFF, and down is ON. Did I say "single-coil"? Yes, I did. There's only one coil, wrapped around the blade. The faux "polepiece" screws don't have anything wrapped around them at all.

It's intriguing indeed; but way beyond my level of expertise. So we'll leave it at that. In any case, you'd be able to get two more sounds than say; a stock Fender Strat. I mean, imagine the how cool it would be to pair the Neck and Bridge pickups, or all three together? Yes, this Hofner 173 would be able to do just that; were it in working condition.

From the switch unit, the signal from each pickup is fed to a dedicated 100K Log (Audio Taper) pot; hooked up to a 0.033uF ITT MPT-1 tone cap. After passing through the Tone pots, the signal ends up at a 220K Lin (Linear Taper) Master Volume pot; which controls the output to the mono jack socket.

The DPDT switches are still functioning, but the same cannot be said for the pots or jack socket. These would have to be replaced, should the owner decide to proceed with repairs. Meanwhile, the only working pickup is the Neck (Bass). The DCR reading is a healthy 7.14K. Poor Discant (Middle) and Treble (Bridge) have gone open circuit; it would seem. 

I actually opened up the Treble (Bridge) pickup, and measured the DCR off the coil itself; but to no avail ~ it was most certainly shorted out or broken deep within. On the plus side, at least I got to examine the innards of an H513 and confirm that these babies are indeed single-coils. With that, I bid you adieu. Thanks for visiting, and I'll see you again soon. Stay safe, stay healthy, and God bless :)

 

Hofner 173 Wiring Diagram