Neck warped.

numptydumpty · #1 01-19-2010, 01:01 PM

So I have a cheapo P copy 70s vintage and the neck is wonky.If I adjust the truss rod I can get the G side straight but the E side has a backbow.If the E side is straight there is too much relief on the G side.I was thinking of sanding the frets level on a flat surface.Should I get the neck as straight as possible on the G side and take lots of metal from the middle of the E side,or get it to some mid-position to take material from both ends of the G side and less from the middle of the E side?

Benjamin Strange · #2 01-19-2010, 08:00 PM

If you have to ask these kind of questions, it might be best to take it to a qualified tech.

If your neck is truly warped, sometimes a fret level can compensate for it. The trick is to level the frets while the neck is under tension, otherwise you'll never get it quite right.

**251** · #3 01-19-2010, 08:36 PM

Quote:

Originally Posted by numptydumpty

So I have a cheapo P copy 70s vintage and the neck is wonky.If I adjust the truss rod I can get the G side straight but the E side has a backbow.If the E side is straight there is too much relief on the G side.I was thinking of sanding the frets level on a flat surface.Should I get the neck as straight as possible on the G side and take lots of metal from the middle of the E side,or get it to some mid-position to take material from both ends of the G side and less from the middle of the E side?

It does sound like a slight warp or an irregular grain feature in the wood. OTH, the next lighter gauge strings might let you back off the truss rod enough to give you a straight neck at pitch. You will have to intonate, set string height & pick up height when you set up different strings

Sometimes a bass that has been under too much tension for a long time will recover, given a chance. Release the strings, release the truss rod nut, let the bass sit out in a stand for 2, 3, 4 days. Look carefully, is the neck straight now? If it is, tune it to pitch adjust the truss rod. Watch & see if it goes off again.

Sometimes a bass is made with a piece of wood that that should have gone to the scrap heap. If the neck is warped now, tuned to pitch & set up + warped with no neck tension. Take it to a pro to be fixed or buy a replacement neck.

numptydumpty · #4 01-20-2010, 10:18 AM

Thanks Ben. How do you level the frets under tension?Would the strings not be in the way?
Thanks 251 but the bass is next to worthless even with a good neck so not going to throw lots of money at it.Have already bought a used Squier neck for it but heel dimensions are all wrong plus truss rod was maxed out and it feels like it is made of rubber.Now that is a piece of wood for the scrapheap!

Benjamin Strange · #5 01-20-2010, 10:38 AM

Like this:

numptydumpty · #6 01-20-2010, 12:31 PM

And I just gave my last one away

Craig_S · #7 01-20-2010, 03:25 PM

Benjamin is right. That's the way to handle it. Unfortunately, the neck jig costs about 10 times what your bass is worth.

I'd start saving for a used bass, if I were you.

202dy · #8 01-20-2010, 04:19 PM

Interesting thread. Everyone except Benjamin has pronounced this bass a goner. Yet no hard data has been posted by the OP.

Incidentally, sometimes a neck that is otherwise perfect will pull into relief differently on either side of the neck. Given the existing information, this is the only diagnosis that fits the facts.

Craig_S · #9 01-20-2010, 04:26 PM

Quote:

Originally Posted by 202dy

Interesting thread. Everyone except Benjamin has pronounced this bass a goner. Yet no hard data has been posted by the OP.

Incidentally, sometimes a neck that is otherwise perfect will pull into relief differently on either side of the neck. Given the existing information, this is the only diagnosis that fits the facts.

Did you read the part the OP posted about one side having a back-bow while the other side has proper relief? How else would you explain that?

GlennW · #10 01-20-2010, 04:30 PM

I used a heat lamp on a twisted neck and got some improvement. Instead of using two lights (one pointed at each side of the neck to straighten it) I used one lamp pointed one side in hopes of straightening one side. It helped a lot.

From your description, I'd try it with the lamp pointed at the G side while jigged up with a backbow. It's a trial and error deal. The 300 watt lamps can be found at Home Depot.

If you want to try it say so and I'll be more specific.

Search this forum for "heat" and "lamp", you might find something.

**251** · #11 01-20-2010, 04:45 PM

8-(

8-) time for a new bass!

202dy · #12 01-20-2010, 05:02 PM

Quote:

Originally Posted by Craig_S

Did you read the part the OP posted about one side having a back-bow while the other side has proper relief? How else would you explain that?

Quote:

Originally Posted by 202dy

Interesting thread. Everyone except Benjamin has pronounced this bass a goner. Yet no hard data has been posted by the OP.

Incidentally, sometimes a neck that is otherwise perfect will pull into relief differently on either side of the neck. Given the existing information, this is the only diagnosis that fits the facts.

Please read the second paragraph of my last post. That explains it all.

numptydumpty · #13 01-21-2010, 04:27 PM

Lots to think about here thanks.Found info on the web about removing fretboard and sanding neck level,maybe that's what's needed.Don't know if board will come off without damage but apparently it's possible to refit it afterwards.
Glenn ,are we talking just a high wattage halogen lamp (300/500 watts readily available here) or is there some special infra-red lamp?

Benjamin Strange · #14 01-21-2010, 09:23 PM

No, no, no - you don't need to take the fretboard off. IF you need to actually heat press the neck, the way to do it is to clamp it to a heated steel beam, shim it in the opposite direction of the twist, and let the heat do the work. Sanding the neck under the fretboard is just asking for trouble.

GlennW · #15 01-21-2010, 09:42 PM

Quote:

Originally Posted by numptydumpty

Glenn ,are we talking just a high wattage halogen lamp (300/500 watts readily available here) or is there some special infra-red lamp?

I just looked at the box. It's a Phillips 250w "Heat Light", the kind that heats bathrooms. I use the clear ones, they also come in red. One of those with a aluminum (?) holder like they use on construction jobs, should cost under $15 for one bulb and one holder.

You'll also need some stuff to jig it up. I usually use a 4" c-clamp, a 2' metal level (something that'll stay rigid when clamped), a couple of small blocks, scrap leather, and a framing square (or other suitable straightedge to guestimate the arc after clamping).

Here's a pic of the light. Disregard the jig, it's for correcting a ski jump at the heel.

Benjamin Strange · #16 01-21-2010, 09:44 PM

If you're using a 250w bulb, you're could cause a lot of problems by applying too much heat: frets lifting, fretboards coming unglued, finish burning, etc. 75w should be plenty.

GlennW · #17 01-21-2010, 09:47 PM

If you keep the bulb 6 1/2" - 7" from the neck you should be ok. If it's nitro, start off around 9" and sneak up on it every half hour or so paying close attention not to bubble the finish.

I've heated poly finished necks with two of those lights for 8+ hours 6 1/2" away and never had a problem. You need to devote a day to it, and be prepared to babysit it.