Trying to fix a worthless Bass

[Matt Liebenau]

So life has been quite busy and I haven't had a chance to work on this in a while. I decided to forgo fireworks tonight so that I would have a 6 hour window at home to heat this thing up for a while. What you see is a 2x4 wrapped in a towel under the middle. To each side of that is a hot pack. Then there are four clamps. I went with two on each side because as you may recall the neck isn't just bowed but it is also twisted. So the treble side at the heel is torqued down a little tighter than the other three clamps. Hanging above it is two 100 w ceramic heat lamps. Whatever video I saw this in the guy had mounted sockets to a board, but I actually felt like using a boom mic stand was genius. I can feel how hot the neck is getting and move it lower if I think it needs more heat or move it up if I think it's getting too much heat. I'm watching The binding to make sure it doesn't melt as @Turnaround suggested. You may notice two little bamboo sticks at each end. I put those there thinking they would help me adjust the twist in the neck. They did help somewhat in as much as I was seeing the movement as I was adjusting the tension, but I realized that plan was imperfect because I can't be sure that they're both sitting in exactly the same spot on the radiused neck. So between the clamps I have just over a foot of exposed wood so the way I checked the twist was to rock a ruler at each fret edge the same way you would work one of those little fret tools except a foot long. Once it seemed like it had the same amount of play at each edge I figured that would hopefully be the spot that would correct the twist. Then after baking for 6 hours I'm going to take away the heat sources and leave it clamped there for a week to give the glue and the wood fibers plenty of time to adjust to their new position. I literally just put the heat on this, wish me luck.

I hope you have all success with this. My only caveat is that when heat or steam bending wood you often have to go a bit further then where you want it to end up as the wood will spring back once it’s released from the clamps. OTOH if that happens here I suppose you can try again and bend it a little further next time.

 

[Markshan]

I hope you have all success with this. My only caveat is that when heat or steam bending wood you often have to go a bit further then where you want it to end up as the wood will spring back once it’s released from the clamps. OTOH if that happens here I suppose you can try again and bend it a little further next time.

I appreciate that and it's clamped into a back bow and I have put the new nut on just snug. The 12" ruler shows about a 1/8" of play on the back bow. Having never done this before I didn't want to be too aggressive. If this doesn't get me where I need to be I'll increase the back bow on the next heat cycle.

 

[Markshan]

So I took the clamps off when I got home tonight. It's gone from having a very severe bow to having a very subtle back bow. And that is without string tension so I suspect the strings will probably pull it straight. The process also lessened but didn't completely eliminate the twist. I'm going to let it sit for a couple of days and see what happens next and then perhaps I will try another clamp up just targeting the area that's twisted.

 

[Markshan]

Checking it with the notch tool it seemed that all of the back bow was right at the 8th fret, which was the location of the 2x4 when I clamped it. So today I flipped it over and put the 2x4 in the same spot and clamped directly to each side of the 2x4 to localize the pressure. I didn't bother with heat lamps and everything I just threw a hot pack on it and I'll check it when I get home in hopes that it straightens that spot but doesn't do anything else. Since it seems my first treatment was so effective I'm going to be a little less aggressive with subsequent actions. I don't want to turn this thing into a rumble strip by chasing each spot but not getting any of them completely flat. It already should be much more playable than when I started.

 

[Markshan]

So I just got home and checked it again and the hump is less drastic than it had been. I checked the frets with a three fret tool and there are only four high frets. Seven, nine, 17, and 19. So then I checked the whole neck at once with a square and the seventh fret is still the highest fret. But the rock was down to about a 16th of an inch whereas before it was probably 3/16 to a quarter. So I'm feeling pretty good about where I'm at with this. I'm not going to screw around anymore with the middle of the neck yet. I'm going to do one more clamp at the heel to try to get rid of the last bit of twist, and fill that cavity with epoxy once I have the twist corrected. Then I'm going to put it back on and string it up see what happens once there's string tension on it. Then I'll decide if I need to do any more clamping and heating, or if it's time to dress the frets, unless somebody has a better suggestion for me.

 

[Markshan]

Right after I said I was going to be less aggressive with subsequent treatments I went and did this.

 

[Markshan]

I wished since I was worried about a subtle ripple that I had one of those heat bars that clamp to the fretboard. Since I don't, I decided to clamp it at the high spots against the straight surface I am working on. As you can see I got a tad aggressive with the heat lamp. I planned to sand the old gloss finish off anyway, hopefully the burn will sand out. If not, it's only on the back and will serve as a reminder of my first neck straightening project.

 

[Markshan]

I've been giving it some more thought and maybe if that spot won't sand out I'll burn it in three or four more spots and make it a pattern instead of an accident. Pete Townsend once said that when he's playing a solo and he hits a wrong note he will return to that note 3 or 4 more times and then people think he's being edgy instead of just making a mistake.

 

[Markshan]

Okay I've reached another spot where I feel like I need some advice. @vaesto @Turnaround @96tbird @60bass , as well as anyone who cares to give an opinion. So other than the mishap with the burn on the back of the neck this project has been a rousing success. I feel like I've taken something that was considered garbage by at least the last two owners which would be 30 years and got it to the point where it should be playable.
The treble edge is just about as close to perfect as you could expect from something that had an almost 1 inch bow in it when I started. Then there is a ski jump that is incredibly subtle in the middle but works its way to about a 16th of an inch at the bass edge. I'm not sure how I would clamp around neck at one edge but not the other. I'm also not sure if it's even worth it
So my question is, do I try to straighten it further at the risk of making it worse, or do I just leave well enough alone and start to work on the frets and the finish? TIA.

 

[Markshan]

Also @Matt Liebenau

 

[johnh89]

Just bumped into this thread . I love a lost cause . Spectacular work so far my friend . I will follow with interest .

 

[Markshan]

Just bumped into this thread . I love a lost cause . Spectacular work so far my friend . I will follow with interest .

Thanks. Would you try to get the last bit straight or is the risk of messing up something else too high?

 

[johnh89]

I would continue with caution . Spend a bit of time to come up with a plan . It may be that it is good enough as is . Until it is strung up you will never know . Even 1/16th of an inch , whilst considerably better than where you started , is too much to correct by dressing frets .
You can always pull the frets , plane off the fretboard and make yourself a new fretless board . I did .

 

[Markshan]

I have a fret pull project that I am also working on. I considered refretting this one of I had to.

 

[Turnaround]

Several things come to mind.

First, that burn - the heat was too localized. Even when you are trying to flatten a specific area, you should heat a much larger area evenly to relax all of the interior tensions.

You may be chasing some diminishing returns. But if you want to see it through, I would next remove the fretboard and go about flattening the neck without the fretboard. Try to get the neck itself flat. Or failing that, get it as flat as possible with heating, then plane it truly flat. The fretboard will be fairly flexible, but when you glue it back on the neck, it will add to the rigidity of the neck. If you had to remove any significant amount of wood planing the neck, I would add a veneer layer to make up the difference.

If you are unable to get the twist out of the neck during the heat treatment, I would also flatten the neck with the fretboard off. It may mean removing a fair bit of wood, which you would make up with another layer of new wood as above, then reattach the fretboard.

I agree with the approach of filling in that curved slot at the end of the the truss rod.

Getting back to my first comment about diminishing returns. You can buy a complete Beatle Bass kit (unfinished) with all the necessary parts for $250. Even if you successfully restore the bass it will won't be worth much. The neck on these instruments is made with an inferior grade of wood and they just don''t stand up. There's a good chance that after all your effort the neck will distort again. It's really a question of what is it worth to you? Maybe you can't put a price on the satisfaction you get from working on it. You need to decide when close is good enough.

Mine got a lot of attention because of its cool colour.

 

[Markshan]

Getting back to my first comment about diminishing returns. You can buy a complete Beatle Bass kit (unfinished) with all the necessary parts for $250. Even if you successfully restore the bass it will won't be worth much.

See my thread title. It's really not about that. At first it was about rescuing an orphan (you'd have to know me, I adopted and raised two special needs kids). Now it's just about being a stubborn old man who refuses to say "uncle". Neither of those personality traits (or flaws, depending on who you ask) would be satisfied by making a purchase. At least two of you are telling me to keep at it, that's all I needed to hear. And if I get it perfect and it bows again in a week I'll have learned a lot and will still have a cool wall hanging, so nothing lost either way.

I appreciate your encouragement.

 

[Matt Liebenau]

Not sure. I have no idea about clamping a neck to try and remove a twist. I’ve done the heat and bend thing. Sometimes it seems to stay other times in a few months or a year the neck is a pretzel again. I don’t remember if you said wether the frets were out or not. If they are, you could try compression fretting which is installing frets with larger tangs to try and flatten the neck out. The ideal would be for the neck to be straight on its own of course. At this point the only thing you have to loose by continuing to experiment is time.

 

[johnh89]

Stick with it man . I love a lost cause and have rescued more than a few . A great way to learn . Man made it so man can mend it .

 

[60bass]

Okay I've reached another spot where I feel like I need some advice. @vaesto @Turnaround @96tbird @60bass , as well as anyone who cares to give an opinion. So other than the mishap with the burn on the back of the neck this project has been a rousing success. I feel like I've taken something that was considered garbage by at least the last two owners which would be 30 years and got it to the point where it should be playable.
The treble edge is just about as close to perfect as you could expect from something that had an almost 1 inch bow in it when I started. Then there is a ski jump that is incredibly subtle in the middle but works its way to about a 16th of an inch at the bass edge. I'm not sure how I would clamp around neck at one edge but not the other. I'm also not sure if it's even worth it
So my question is, do I try to straighten it further at the risk of making it worse, or do I just leave well enough alone and start to work on the frets and the finish? TIA.

You've done well to get it this far and have had a nice learning experience. That said, I agree with @Turnaround as to the best way to truly repair the neck BUT is it worth it? These basses had marginal wood necks at best and junk at worst even when they were new. There's a high possibility the neck will just snap back again down the road. If I was truly wanting a Beatle bass I'd get a kit. A modern kit, even the cheapest one will be far better then the old bass is. You still get experience assembling and you'd end up with a bass you could actually be able to play and enjoy as well as learning and/or practicing to apply a finish.

 

[Markshan]

You've done well to get it this far and have had a nice learning experience. That said, I agree with @Turnaround as to the best way to truly repair the neck BUT is it worth it? These basses had marginal wood necks at best and junk at worst even when they were new. There's a high possibility the neck will just snap back again down the road. If I was truly wanting a Beatle bass I'd get a kit. A modern kit, even the cheapest one will be far better then the old bass is. You still get experience assembling and you'd end up with a bass you could actually be able to play and enjoy as well as learning and/or practicing to apply a finish.

If I can't fix this one I'll get a hunk of maple and build a new one. I can't see doing that much work to a plywood neck.