Completed July 30, 2013
Body and neck is in good shape which is a little hard to find. There are a lot of gibsons out there with broken headstocks or headstock repairs. It is more common to find project rebuilds that are Fenders with bolt on necks since they are easier to correct. The body on this one has been cut up. A good project guitar since the body has been abused already so no issue with modifying a potential vintage guitar. A cutout was made for a middle pickup and two 'mystery holes' drilled below the tailpiece.Ebay purchase at reasonable price considering the condition. Basic SG with some wear and and cracks in the finish from almost 15 years of use.
Ebony fretboard
Replaced grover tuners
Original electronics in place with 2 volume and 2 tone pots
Light weight- 4.5 pounds
Project will be to build a guitar with maximum flexibility to get tones from the guitar rather than after guitar effects. This means the ability to split the coils and play any combination of 1, 2 or 3 pickups. Since there are 2 coils in each pickup this allows for over 30 combinations. On-board active circuits will also be added.
Step 1- Basic Circuit
First draft with 2 volume and 2 tones
Decided on 1 volume and 3 tones.
The schematic shows a preamp buffer which changes the output signal from high impedance to low impedance and has no other effect. This stops the loss of tone highs as the signal passes through cables and effect pedals on its way to to the speakers. I will leave the buffer out for now and decide later if I need it.
More here on the buffer with a demo:
http://www.youtube.com/watch?v=dMxwT7BT7oE&feature=c4-overview-vl&list=PLCzwfVTc1jWQByHsiRM7I0-x1Oze5-UPT
Pickups installed on the pickguard and wires out the back with temporary connection to the controls. After testing like this decided on the 0.047 capacitors for tone control instead of the 0.022 in the original plan.
Then went back and added the wiring for splitting the coils and tested again. The only issue was poor grounding with hissing and buzzing when testing but that would be straighten out on the final assembly.
The only way this works with a lot of flexibility and not needing to drill holes in the guitar is using the 6 position switch from Stewmac. The issue is to come up with a wiring that allows a format you can remember and makes sense when holding the guitar. Took a lot of time since the examples on the web did not cover this but wanted the positions close to the pickups to activate the neck and middle pickups and down position should activate the bridge and middle pick ups. Had all this worked out then the switch failed and a different updated version was provided. Redid the switching pattern and came up with this for the new switch.
The only good thing is the new switch is much sturdier and has the Gibson color knob head.
The only setup problem was intonation on the low E string. Open it tuned to E but at the 12th fret it was E flat. The nut was likely over filed to lower the action so for now until the nut is replaced a second thin cheater wire is under the E string. This fixed the problem for now.
Sound- It does everything it should. 2 or 3 split coils are thin like a strat or telecaster and 2 or 3 humbuck have the Gibson tones.
Done except for the final tailpiece trim- July 12,2013
Gibson larger trapezoid tailpieces were to narrow to cover the holes so went with ebony instead. Found a cheap piece online.
Decided on 1 volume and 3 tones.
The schematic shows a preamp buffer which changes the output signal from high impedance to low impedance and has no other effect. This stops the loss of tone highs as the signal passes through cables and effect pedals on its way to to the speakers. I will leave the buffer out for now and decide later if I need it.
More here on the buffer with a demo:
http://www.youtube.com/watch?v=dMxwT7BT7oE&feature=c4-overview-vl&list=PLCzwfVTc1jWQByHsiRM7I0-x1Oze5-UPT
Step 2- Parts: Pickups & Other
The pickups will be Dimarzio humbucks and there is a lot of info on their page. Selected the Super Distortion as a bass heavy pickup for the bridge and Super 2 as a treble heavy pickups for the middle and neck. This setup is pretty common in three pickup guitars.
Other:
Pickup selector- Stewmac 6 position freeway switch
Pots volume 25k and tone Dimarzio 500k push pull
Pots push/pull – DiMarzio coil tap leaving ‘north’ coil active. Split when pulled out
Capacitors -0.047uF
All wires are 22 guage copper except the ground which is heavy braided ground wire from Stewart McDonald
Started with a layout board from 3/16" plywood to make sure wires and layout would fit. This shows the wiring for the signal through the switch to the jack and and connection to the tone pots. Black heat shrink cover is added where needed to keep neat.
Other:
Pickup selector- Stewmac 6 position freeway switch
Pots volume 25k and tone Dimarzio 500k push pull
Pots push/pull – DiMarzio coil tap leaving ‘north’ coil active. Split when pulled out
Capacitors -0.047uF
All wires are 22 guage copper except the ground which is heavy braided ground wire from Stewart McDonald
Step 3- Circuit Assembly and Test
Started with a layout board from 3/16" plywood to make sure wires and layout would fit. This shows the wiring for the signal through the switch to the jack and and connection to the tone pots. Black heat shrink cover is added where needed to keep neat. Then went back and added the wiring for splitting the coils and tested again. The only issue was poor grounding with hissing and buzzing when testing but that would be straighten out on the final assembly.
Six Position Switch
The only way this works with a lot of flexibility and not needing to drill holes in the guitar is using the 6 position switch from Stewmac. The issue is to come up with a wiring that allows a format you can remember and makes sense when holding the guitar. Took a lot of time since the examples on the web did not cover this but wanted the positions close to the pickups to activate the neck and middle pickups and down position should activate the bridge and middle pick ups. Had all this worked out then the switch failed and a different updated version was provided. Redid the switching pattern and came up with this for the new switch.The only good thing is the new switch is much sturdier and has the Gibson color knob head.
After the new switch and all wiring is set the cavity is lined with copper foil, the harness is placed in the cavity and connected to the pickup wires. Still working on solder technique but all connections pull tested solid. The bridge ground enters from the upper left of the picture and goes right to the volume pot, switch and jack. Need to do this for solid grounding on the signal path and avoid the hiss from poor ground connections.
Step 4- Setup and Trim
The action set up fine and is very easy tight to the frets. The neck angle is about 4 degrees off parallel with body top and is the Gibson spec. I never noticed this before but the pickups are higher in the bridge and lower at the neck.
Sound- It does everything it should. 2 or 3 split coils are thin like a strat or telecaster and 2 or 3 humbuck have the Gibson tones.
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| Switch with knob head and vintage 5-ply pickguard from 70's SG |
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| Knobs with middle tone pulled splitting the coils |
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| Need to cover the extra holes from the guitar butcher previous owner. Maybe something like the Derek trucks tailpiece decoration added to his SG |
Done except for the final tailpiece trim- July 12,2013
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| Here is a rare 60s SG with a 'short' tremolo Maybe add the tremolo or old tailpiece one day if I can find one |
Gibson larger trapezoid tailpieces were to narrow to cover the holes so went with ebony instead. Found a cheap piece online.
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| Raw ebony cut and sanded |
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| Fretboard stain and waxed |
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| Done |
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