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Posted: Wed Dec 09, 2020 4:26 am
by astro
Nick wrote:Tbh this build had me worried but it actually came together nicely. Kind of a shame the grain is hidden but it doesn’t look bad either.
I agree, it’s unfortunate about the grain. I really wanted a transparent cherry finish and I should have tested the “stain� I bought on scrap wood before applying it to the body. Instead of clear cherry I ended up with opaque brown. Lesson learned. I will always test first from now on when using unfamiliar products for finishing.

When the weather permits I might strip the body and redo the finish with a proper sprayed finish. I recently found a source for aerosol spray cans of nitro in Fender and Gibson colours here in Canada, so I might try that out. I’ve never done a nitro finish before, this time I’ll test on scrap wood before committing to painting the body!

Posted: Wed Dec 09, 2020 5:24 am
by kingkiller
It looks great all put together! I’ll have a long winter being stuck inside so I might pick up a kit and try to build another one again.

Posted: Wed Dec 09, 2020 8:17 am
by NickS
Nice job. Did I miss what you did to the back of the neck? Tung oil as per the original plan?

Posted: Wed Dec 09, 2020 12:25 pm
by Thom
You did a good job - nice one.

Posted: Wed Dec 09, 2020 3:42 pm
by astro
So I plugged the guitar into some amplifiers today... and the noise/hum is unbearably loud! I mean REALLY loud! It's my first P90 guitar and I know they're noisy pickups, but the hum is louder than the notes. My basement is full of fluorescent lights and was wired by an orangutan masquerading as an electrician, so I turned off every single light in the house and played in the dark... the noise was only about 5% less than with the lights on.

The weird thing is, if I don't touch the strings (or any other grounded part of the guitar), the noise goes away. The noise only happens when I am touching a grounded metal part of the guitar. I also noticed that turning the volume pot away from maximum, even a little bit, causes the notes turn to indiscernible mush (and the loud hum/noise stays).

Although I know how to solder fairly well and I can follow wiring diagrams, my actual understanding of electronics and electrical theory in general is completely non-existent. Would I be correct in assuming this is some kind of grounding issue? Or could my volume pot be a dud? I used this wiring diagram and as far as I can tell I wired it the same as the diagram:

Image

Posted: Wed Dec 09, 2020 4:07 pm
by astro
BTW the second black wire from the output jack, the one in the diagram that is shown going to the ground symbol, I wired to the bridge to ground the strings. Is this correct or did I do an screw up? And I lined the control cavity with copper shielding tape, and the tape is grounded as it touches both pots (I tested it), did I do an screw up here too?

Posted: Wed Dec 09, 2020 4:20 pm
by Bacchus
Hmmm, I'm terrible at electronics, but might the shielding contacting both pots possibly be causing a ground loop?

I'd insulate the back of the pots with some tape, then wire the shielding to the same ground point as everything else. Probably.

Posted: Wed Dec 09, 2020 5:34 pm
by bobnagy
The connections to the output jack are reversed/backwards.
Red wire should go to the tip, black wire to the sleeve.

Posted: Wed Dec 09, 2020 6:16 pm
by astro
bobnagy wrote:The connections to the output jack are reversed/backwards.
Red wire should go to the tip, black wire to the sleeve.
BINGO!

I reversed the connections to the jack and now it works!!!!

Thank you so much!

Posted: Wed Dec 09, 2020 6:40 pm
by astro
NickS wrote:Nice job. Did I miss what you did to the back of the neck? Tung oil as per the original plan?
You didn't miss it, I forgot to mention it. I didn't end up using Tung oil. I just used the same wipe-on polyurethane on the back of the neck and it came out pretty nice

Posted: Wed Dec 09, 2020 10:39 pm
by dots
excellent work, and glad the noise issue ended up so simple to fix. you should be proud of that guitar!

Posted: Thu Dec 10, 2020 12:51 am
by aen
Gee whiz that looks great! I hope it sounds at least half that good.

Posted: Thu Dec 10, 2020 1:20 am
by astro
It sounds really good!

I read a lot of reviews of these types of kits before buying, and pretty much all of them said that everything but the wood was junk, plus they needed fret jobs and new nuts. I don't know if I got lucky or if this particular kit company (Saga) has better QC than others. I was expecting to have to do a lot more work other than painting. In the end, I only really needed to replace the tuners. I replaced the electronics too but I never bothered testing the stock ones, maybe they were good as well. Oh, and I replaced the knobs too but that's only because the stock ones didn't fit on the pots that I bought.

The guitar has the stock kit pickup in it, and it sounds fantastic through both my guitar amps (a Roland Micro Cube and a Fender Concert II) so I'm going to keep it for now and I'll only upgrade if I ever happen to get to hear in person a different P90 that sounds markedly better.