Fixing a bowed / warped bass neck

[MichiBass]

So I bought a used Mexican Fender Jazz Bass made in 1994, which has a bowed / warped neck (I was aware of that, bought it for quite cheap because of this issue):

The truss rod works fine, I am able to straighten the neck a bit, but the neck is pretty bent, so this will take a while to straighten.

The question is: Is there a way to speed up the straightening process? Like putting it in the sun or in the bathroom while I shower, something to soften the wood so that it moves back to the straight position?

Any other tips in order to make this neck straight again?

Thanks,

Michi

 

[vaesto]

Hi.

Do like that and apply heat at least 60C for several hours. You need to bend the neck the opposite direction and amount as it is now. Fully Release the truss rod before straightening.

You may also pre-heat the neck before straightening it, the wood will be softer and easier to manipulate. Don't hurry and let the neck to cool down slowly afterwards.

Sun, bathroom heat/moisture, short burst of temperature (e.g. heat gun) won't help. You need constant dry heat for at least several hours.

If you have big enough oven to fit entire neck - put it there and set 70-80C.

Best of luck!

 

[jallenbass]

I clamped a Squier neck that had excessive forward bow to a 2x4 and put a rolled up hand towel under the middle of the neck and put it out in the summer sun for about a week. Worked like a charm.

 

[-Boscoe-]

Hi.

Do like that and apply heat at least 60C for several hours. You need to bend the neck the opposite direction and amount as it is now. Fully Release the truss rod before straightening.

You may also pre-heat the neck before straightening it, the wood will be softer and easier to manipulate. Don't hurry and let the neck to cool down slowly afterwards.

Sun, bathroom heat/moisture, short burst of temperature (e.g. heat gun) won't help. You need constant dry heat for at least several hours.

If you have big enough oven to fit entire neck - put it there and set 70-80C.

Best of luck!

Sorry to resurrect this, but I think my oven's minimum temperature is 250 degrees Fahrenheit (121C). I've heard of others microwaving bags of rice grains in socks and laying them on. Any other suggestions for getting the neck to about 60C?

 

[kgbeast]

You can try a space heater in a small closet or a large box. Coupled with power controller like this ( https://a.co/d/geyJwHd) should be doable. You will need to fiddle with location of it as if it is inside the closet, it's overheat protection will kick in and stop well before the needed temp.

 

[vaesto]

Sorry to resurrect this, but I think my oven's minimum temperature is 250 degrees Fahrenheit (121C). I've heard of others microwaving bags of rice grains in socks and laying them on. Any other suggestions for getting the neck to about 60C?

Well, the photo here with 60-65C was taken on first attempt. The second one was hotter: 80-85C. You actually need that higher temperature.

I haven't yet seen household oven big enough to put the bass neck in one piece The closest "oven" solution I could think of is one we normally see in pizzeria (can't say if they could run at 80-90C, though).

Another variant is a chambered big box and heater gun. And you also need a thermometer in your working chamber.

 

[-Boscoe-]

The box is a good idea, and I have a really nice heat gun with temperature control, but I suspect it wasn't meant to run for hours at a time.

I have a double oven and I wonder if I take out all the shelves if I might be able to fit my neck in diagonally. I'll try that. If that doesn't work I might try the trick someone else mentioned which was to microwave socks full of rice grains and pack them around the neck in a box. Obviously the temperature control isn't great with that idea.

 

[Bruce Johnson]

The box is a good idea, and I have a really nice heat gun with temperature control, but I suspect it wasn't meant to run for hours at a time.

I have a double oven and I wonder if I take out all the shelves if I might be able to fit my neck in diagonally. I'll try that. If that doesn't work I might try the trick someone else mentioned which was to microwave socks full of rice grains and pack them around the neck in a box. Obviously the temperature control isn't great with that idea.

For your reference:

The pros (like the guys at Warpedneck.com) wrap the neck with silicone heating blankets, electric powered, temperature-controlled. And they let them soak like that for a day or two, on a schedule of temperature vs hours. That's how they get the right amount of heat deep down in the neck, without getting it too hot out at the surface. When it gets to the right temperature inside, then they apply the clamps and bending, and hold it like that for some number of hours, while still applying the heat at a controlled temperature. Then they shut off the heat, keeping it in the clamps, letting it cool down for some more hours. I understand that the process takes several days. The schedule of hours and temperature comes from experience.

 

[-Boscoe-]

Thanks, that makes a lot of sense. I think I'll try warming up the neck either in the oven if I can somehow get it in there, if not I'll lay a couple of socks filled with hot rice on it until it's warmed up, then clamp down to induce a slight backbow, then put fresh hot socks on it and let it cool down and sit for a couple of days. That might be enough to correct it as I think this bass was just sitting around for a while in the store without an adjustment. The fretboard was also really dry so perhaps the strings just pulled it out of alignment over time.

Thanks again for all the tips.

 

[lark_z]

Heating pad worked well for me.

https://www.talkbass.com/threads/options-for-neck-with-too-much-relief.1486212/

 

[-Boscoe-]

I read through that thread and I think that's the solution for me. Thank you! Also appreciate how you documented the whole process.

 

[maturanesa]

In a Fender it is not better to replace the neck and save all the work you got to go trough in order to straight a bowed one?

 

[-Boscoe-]

It's a StingRay so there aren't very many cheap, high quality replacement necks out there. But more importantly, I'm a pretty handy guy and I got this $900 bass for $300 knowing it has a warped neck so I'm in it for the challenge and the sense of accomplishment if I can manage to fix it. I already do my own setups and electronics work so this kind of amateur luthier stuff is fun for me. Gives me an excuse to buy any tools I might not already have.

 

[Bruce Johnson]

In a Fender it is not better to replace the neck and save all the work you got to go trough in order to straight a bowed one?

Why would that be "better"? I believe in repairing basses, not throwing them away when they have a problem. If you are doing a repair like this yourself, It's not really that many hours of work. Just a little bit of time and patience. And you can be proud of it when you've personally repaired it.

 

[lark_z]

It really depends on what you consider to be work and what you consider to be enjoyable. As Boscoe and Bruce ably point out, some really enjoy this sort of thing, as do I. Others do not and would find the exercise to be a huge waste of time and mental effort. To each his own. The beauty of the bolt-on neck is that we have options that do not require skilled lutherie.

 

[-Boscoe-]

It really depends on what you consider to be work and what you consider to be enjoyable. As Boscoe and Bruce ably point out, some really enjoy this sort of thing, as do I. Others do not and would find the exercise to be a huge waste of time and mental effort. To each his own. The beauty of the bolt-on neck is that we have options that do not require skilled lutherie.

One would assume that in a thread named "Fixing a bowed / warped bass neck" that one would find people interested in fixing things instead of replacing them.

You're right though, it does not make financial sense for me to fix this. My labor is valuable enough that the time I will spend fixing this is more than the dollar value of the bass. But playing bass and fixing things are my hobbies and I don't like to throw away fixable things.

 

[kgbeast]

It is strange for me to listen about how replacing this neck is easier or that time is money, or labor is valuable and so on.
It is the same as telling a base-jumper that it is a lot cheaper and safer to take an elevator down.

 

[-Boscoe-]

Okay, I’ve started warming the neck up. It’s very loosely clamped to the workbench. Pics attached.

 

[-Boscoe-]

Warmed it up for about three hours until I could feel the bottom of the neck was very warm. Then took off the heating pad and old T shirt. The fretboard was uncomfortably warm to the touch, so I figured it was hot enough. Clamped down until I had a definite backbow and tightened the truss rod.

Heated it another three hours and then unplugged the heating pad and let it stand. I figure I'll let it sit like this for another day or so and take the clamps off and see what the relief looks like.

I forgot to mention that before I clamped it I used a box level with a machined edge to check the relief (I ordered a bass-notched straight edge but it won't be here for a week). I then ran a piece of cardstock underneath the middle and noted which frets it stopped on. Measured the distance and marked the halfway mark (lowest point). I then put the fulcrum under that.

Hopefully in a day or so I have good news!

Last thing - is it possible to remove the truss rod nut on a spoke-style StingRay neck? I was thinking a washer or two underneath it might help with seasonal adjustment. If not, would it help to put a washer underneath the spoke to make it easier to turn? When it's tightened it's sitting up against the neck wood and I think that it might turn more easily with a washer underneath. I've seen videos of people doing this with bullet-style nuts.

 

[tindrum]

Warmed it up for about three hours until I could feel the bottom of the neck was very warm. Then took off the heating pad and old T shirt. The fretboard was uncomfortably warm to the touch, so I figured it was hot enough. Clamped down until I had a definite backbow and tightened the truss rod.

Heated it another three hours and then unplugged the heating pad and let it stand. I figure I'll let it sit like this for another day or so and take the clamps off and see what the relief looks like.

I forgot to mention that before I clamped it I used a box level with a machined edge to check the relief (I ordered a bass-notched straight edge but it won't be here for a week). I then ran a piece of cardstock underneath the middle and noted which frets it stopped on. Measured the distance and marked the halfway mark (lowest point). I then put the fulcrum under that.

Hopefully in a day or so I have good news!

Last thing - is it possible to remove the truss rod nut on a spoke-style StingRay neck? I was thinking a washer or two underneath it might help with seasonal adjustment. If not, would it help to put a washer underneath the spoke to make it easier to turn? When it's tightened it's sitting up against the neck wood and I think that it might turn more easily with a washer underneath. I've seen videos of people doing this with bullet-style nuts.

Yes you can put a washer on a Stingray truss. A few months ago I bought a used Stingray Classic and there was one installed on it by the previous owner.