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Re: fret press ..... there's a thing out nowadays called a "Fractal" fret press that fits all radii. Huge time saver for a pro shop but also convenient for odd necks that arent a standard radius. Cool design. StewMac sells them for $230, Amazon has one for $45, and AliExpress gets em down to $29. ::SHRUG EMOJI::

Re: crowning files ..... a long time ago I did some horse trading with a luthier who also works for StewMac. I wanted set-up and fretting tools and he wanted pedals. I also has no idea where to start when they sell like 20 files for crowning, so I had an expert's opinion to pick out the right one. He sent me one of these diamond crowning guys and I like it just fine. I cant really compare to others because its the only crowning file i've ever used but it works great.

Ovation Magnum (cont.):

Got the new saddles installed and dialed in.



Also shaped a new bone nut from a blank and filed the slots with my new set of nut files.



Once I got it strung up, it became apparent that I needed to spend more time leveling the frets, so I spent a full day today with the fret rocker chasing high spots until it measured good up and down the neck. I made a notched straight-edge so I could make sure the fretboard was completely flat before I started. Recrowned and polished, then oiled the fretboard.



I will say that the satin poly was the right choice on the neck. Every other guitar I've ever owned has had a glossy neck as best as I can remember, but this one feels so much better that now I'm contemplating sanding the sheen off other necks.

I think this one might be a keeper for a while.

Christ alive that looks gorgeous.

daaaaaaaaaaaaamn

Dr Tony Balls wrote: Thu Jan 15, 2026 9:04 am Re: fret press ..... there's a thing out nowadays called a "Fractal" fret press

I want a huge Fractal bench vice. They are super cool. Such and obvious but under used technology.

Supro "Big Star" S6451TR

Just finished this one tonight. Basketcase purchase from Reverb. Missing all the tubes. PT was in pieces, like somebody was attempting to reconnect the wires inside it. Reverb transformer had some charring. One speaker cone completely missing. Every screw was rusty. Fucking filthy.



This schematic is pretty close, but shows a slightly older version of the design with the tube rectifier:



I completely disassembled everything and cleaned the torlex, inside the cabinet, and grille/baffleboard in the bathtub. Power amp chassis went into the ultrasonic cleaner after I removed all the parts I could. I left the wiring. Preamp chassis was rinsed out with isopropyl and scrubbed with a toothbrush, then rinsed again. Also cleaned the original speaker as best I could.
The control panel was removed and soaked in evaporust, then hit with chrome polish. Some of the silkscreen came off in the process, but it still looks better than it did before. Cleaned as much hardware as I could, including the knobs, in the ultrasonic cleaner.

Full recap
New tubes (replaced the 6973 reverb driver tube with a NOS 6CZ5)
New power transformer pulled from a Fender Supersonic 60
New reverb driver transformer
New grounded power cord, death cap removed
New three-spring medium decay reverb tank and tank bag
New Jensen MOD 35 speaker
Replaced 2 missing preamp tube shields
Replaced Valco/Supro/Gretsch-specific 2-prong speaker jack with a standard 1/4" jack
Replaced one of the reverb RCA cables
Shielded preamp sides and back panel with copper tape
Shielded area under power amp chassis with copper tape
Cleaned and lubed pots, switches, and tube sockets
Retensioned the preamp tube sockets
New power tube sockets
New rubber feet
New screws and nuts everywhere
Repainted the missing indicator lines on the knobs

I brought it up on the variac and the voltages looked good all around, but it was humming like crazy. Tried troubleshooting for a couple hours, grounding various points in the signal path to try to isolate where it was coming in, but couldn't wrap my head around it. It was everywhere. Then I realized that this new PT didn't have a center tap on the heater winding and I forgot to add the pseudo center tap. I didn't have any 100 ohm resistors with a high enough power rating, but I found some 2W 47 ohm resistors in my stash and sorted out four that matched. Two in series off each heater leg, tied to ground, and it was finally quiet.

I haven't even had a chance to play it yet since the kids are sleeping now, but here it is with it's 1x15 S6497 "Combo Tremolo" cousin that I rebuilt last year:

Fixing a tascam 464. Did the usual belt replacement. Ran for about 5 minutes. Whole transport went down. Traced the power at “a” to 2v instead of 14. Checked the transistor. Getting 20v out of one side and 2v outs the otherside at j4. So i believe that’s my fail point

Nate Dort wrote: Fri Feb 13, 2026 9:12 pm Supro "Big Star" S6451TR

Excellent work. Also I dont think i've ever seen a schematic with DIAGONAL components? Insanity.

Dr Tony Balls wrote: Sat Feb 14, 2026 7:02 am Excellent work. Also I dont think i've ever seen a schematic with DIAGONAL components? Insanity.

See: 3 phase motor.

Nate Dort wrote: Fri Feb 13, 2026 9:12 pm Supro "Big Star" S6451TR

I haven't even had a chance to play it yet since the kids are sleeping now, but here it is with it's 1x15 S6497 "Combo Tremolo" cousin that I rebuilt last year:

Finally got a chance to A/B these today.

The 1x15 is brighter, more scooped in the mids. Typical 60s Jensen sound.
The 2x12 is more middy and feels wider and fuller. The different speakers, and specifically the Jensen MOD with it's mid-forward sound, is the likely culprit.

I had to sub a 5751 in the V2 position on the 2x12, as I ran out of 12AX7s, and I think that may be the reason for the lack of reverb. It's doing something, but it's quiet. Not enough make-up gain on channel 2. I may also need to tweak the drive side, as this reverb transformer and tank are not the original spec.

Overall volume and clean volume before breakup are pretty similar. It's basically the speakers that are making the difference.