Andyjr1515

Fascinating stuff @Hellzero (and NICE bass ) Only issue is that I don't think ebony expands...certainly ebony fretboards shrink...but that would bend it the other way... But certainly the answer is somewhere in this kind of area and most definitely linked to the weather. Like you, I've come across loads of folks who have had all sorts of things go on this summer. A pro-player I know asked me about his mandolin - honestly, the neck was like a banana! I suggested, especially as they don't have truss rods, that he waits until the weather cools down and then check again. Within three weeks it was completely back to normal!

OK I can't be certain which - and both are equally improbable - but there are two possibilities or a combination of those. A significant factor is that Jack shipped me the neck in early July. And July in the middle of the UK was the hottest month on record with temperatures up to 40 degrees and days above 38 degrees. The neck was kept in a spare room wrapped in bubble wrap and away from direct sunlight. It is likely that the trussrod was still tensioned to give back-bow as I hadn't asked Jack to relieve the tension and didn't start working on the neck itself for some months after receiving it. @Happy Jack had been using the bass and had not experienced any buzz or trussrod issues - which he certainly would have if it had already gained such a degree of Back-Bow (remembering that I was unable to make any tangible difference to that back-bow when I strung it up to full tension this month) So one possibility is what @Hellzero suggests: - that the maple neck wood shrank in length over that period. If it did that, and the ebony stayed the same length, then it would act a bit like a bimetal strip used in thermostats. The maple would try to shrink at the back, the ebony, though, would stop it shrinking at the top (the glue join) and so it would bend. But if that was the case, you would expect that there would be at least a hint of that back-bow remaining once the ebony was removed, as that maple at the top will have been held at its original length through the hot weather and now back to largely normal temperatures. Also, this is fully seasoned rock maple. And shrinkage, even when it is freshly cut, tends to be tangential and radial as the sap hardens and shrinks. There is pretty much nothing in the wood structure that would make it shrink lengthwise. It's why sharp fret ends can often be a problem over the years - the fretboard is shrinking in width - but I've never come across, say, an acoustic with fixed bridge go out of intonation because the neck's getting shorter! The other possibility is: - that the high temperatures allowed a miniscule softening of the glue. Yes, 40 degrees is far short of the 180 degrees that I've just used with my iron to get it off. But remember that it is probable (my bad) that the truss rod was still tensioned throughout that period and the neck would have had a back-bow on it...and normally with a bass or guitar, the neck is straight because the strings are also on so even if softening did happen, nothing would go anywhere. So if there was even the smallest amount of softening, over weeks of very high temperatures it is at least feasible that the fretboard and neck would slide relative to each other, in the same way that laminated sides of acoustic guitars are made. Once the temperatures cooled, the glue would revert to rock-solid and the curve would be permanently set - until the laminate (fretboard) was removed. But there lots of 'ifs and buts' with this possibility too! Both possibilities are in the zone of things I've never ever come across before. It's a bit of an enigma But the good news is that, whatever the cause, the neck IS straight, the fretboard IS undamaged and so all it needs is a clean off of the glue from the mating surfaces and a new truss rod and we will end up with a straight serviceable neck closely followed by a fully playable shell pink bass

No So no

Yes - I don't think it is quite that, but it almost certainly to do with what those two woods have been doing in the unusually hot weather of this summer...and maybe the glue too... I'll post shortly.

That's my fault. I should have said - ignore the truss rod itself on those pictures (which is a single action one). I was using the pictures more to describe which way the neck bends with string tension or truss rod.

It's easier if you think of a bow and arrow bow.

OK - let's start with the basics. With acknowledgement to theelectricluther.com who's website has this picture: For clarity, I'll use this terminology above in the explanation of what I think is going on. Oh - and bear in mind that this is an Andyjr1515 interpretation of the physics of a bass guitar But first of all, some basics and where it was that this neck didn't respond to the basics So - what we are aiming for is pretty much the Flat-Neutral neck when the strings are tightened to pitch But if you didn't have a truss rod or stiffening rods in the neck, the string tension will pull the neck into a bow - Up-Bow in the above diagram. And so what the primary aim of the truss rod is to apply an opposite force - a Back-Bow So if the Up-Bow of the string tension = the Back-Bow of the tightened truss rod, you should end up with a Flat-Neutral Neck. "What about neck relief?" you ask. That's simple. Pretty much ANY Back-Bow will cause the strings to buzz in the middle of the fretboard. So, the way of making sure that, regardless of 'normal' temperature changes and minor tuning differences, you never end up with Back-Bow, is to add a little Up-Bow. And so, if you take the strings off a bass and the neck off, but don't loosen the truss rod, it will have a back-bow, created by the truss rod: And when if you then loosen the truss rod, it should return to how it was when it was made, Flat-Neutral: Our problem was that when I loosened the neck, it still had the Back-Bow. And a big one - at the centre of fretboard it was 2mm higher than the nut and heel That in itself is not that unusual - often a neck will end up with a 'set' bow...and, depending on the circumstances, this can be in either direction. But it is usually small. And with a two way trussrod - capable of bending in either direction - easily correctable. And usually, if it is a back bow, then simply fitting the neck and strings and bringing them up to pitch will straighten it. But in my case, with the strings fitted, there was still a back-bow...and a big one So I turned the trussrod in the opposite direction as much as I dared to create an Up-Bow force so that the trussrod was adding to the tension of the strings to try to counteract the back bow. It reduced the back bow, but only a small amount - from 2mm to 1.5mm. So I put a clamp on at the middle of the neck to try to force it straight and hope that the wood would 'remember' the new position: And after two days of this extreme force... ...as soon as I took the clamp off, it sprang back to exactly where it had been to start with, with a severe back bow with or without the truss rod acting to counter it. And so: - the fretboard just bends to what the neck is doing - and so it must be the neck underneath the fretboard that is bent - and when I take the fretboard off, I would find that the maple neck has a 2mm or more set back-bow in it that I would need to plane flat Hmmm...no. As in the previous post, the neck beneath was flat. Completely flat. Conclusion in the next post

Well...maybe not. Remember who made the neck in the first place

And so, the fretboard removal. Pretty straightforward. After masking the paint on the headstock (I don't want to have to do that again ) I made a small jig so that I could apply pressure from the heel end without having to clamp, and thus possibly damage, the neck: To remove a fretboard, the good news is that almost all manufacturers and builders use Titebond or similar...and it softens with extreme heat. The really good news is that I made this neck...and so I know it's used Titebond. So first tool is an electric iron. I use a cheap travel iron: It takes a LOT of heat. Max temperature and sitting on the wood here for at least 15 minutes before I even start (and this is a thin fretboard!). After 15-20 minutes, I test the joint with a single-edged razor: Then I 'borrow' one of MrsAndyjr1515's pottery tools to start ease the thin steel end between the fretboard and neck: And that allows me to start sliding my perfect-for-the-job piece of sheet steel (it's actually a proper tool designed to help hand bend acoustic guitar sides) into the gap. Then, mm by mm, you can inch (there's a contradiction) the iron and sheet steel forwards. This is after about 45 minutes after the initial success with the razor blade: Patience is the name of the game. Any attempt to rush risks snapping the fretboard. And around 1.5hrs in total - it's off, with neck undamaged and fretboard in one piece : Note the amount of forward bow that trussrod was trying to apply to counteract the 2mm back bow of the neck. So - that maple must be SEVERELY back bowed to resist that truss rod and still bend the wrong way, right? So I put my levelling beam along it, expecting it to be sitting on a substantial hump in the middle of the neck: Flat as a pancake! And that has led me to the position of having never, ever seen something like this and not believing, if it hadn't been right in front of me, that what has happened could happen. But explaining to those interested what has happened will take me a little while. The good news is that all it needs is a new truss rod (because this one is now comprehensively f****d ) and then the fretboard gluing back on

Normally, I would say yes. But in this case no - not needed. It will take me a couple of posts to be able to explain (I'll have to draw some diagrams) but what I've just discovered, I wouldn't have thought possible. Good news is that it is easily fixable. I'll update the progress shortly...but the conclusions will take a little longer.

Neck-wise, the fretboard's got to come off. Another 24 hours with major clamping and trussrod adjusted to help, still a back bow of 1.5mm with the trussrod still in tension. Just to make sure I hadn't had an aberration and originally put the rod in the wrong way up, I loosened it back to the mid point. The back bow was back to 2mm either end - exactly the same as before the clamping. I'm also bothered that the trussrod has now been under a lot of strain for a long time so the best course of action is to take the fretboard off, take the rod out, and see what the underlying neck is doing, fix, replace with new rod and re-glue the fretboard. All being well, the board will be off later this morning.

Oh, that's a shame. But we've all done it I've said in the past that it's not so much that we make less mistakes the more we build, as much as that we get better at fixing them! Repair sounds a good option

Why do you think I've scraped that paint off under the bridge

Oh - I can assure you I've missed more than that Think Hollywood film sets...

Great news on all counts

Knobs on order, straplock ferrules on order, battery sorted, neck still clamped...well, may as well start the final flattening and buffing of the nitro. The flattening is with progressive grades of wet and dry emery and micro-mesh from 800 grit up to 6000 used wet: After that, it's a rigorous workout of Meguiers Ultimate Compound applied with a bobbly (like a facecloth) micro fibre and polished off with a clean lint-free cloth. It's not perfect, and it's not finished, but there are fewer areas for me to have to be judicious with when it comes to camera angles

Yes - managed to track down a bit of packing foam sliver of blue polymer-matrix designed to act as a frequency-neutral sonic substrate to the battery power source. And it doesn't pop the magnet-held hatch off either! Everything stays in place just as it ought to - think Harmony Hair Spray without the hair..., er, or the spray

Low-tech is never a problem with an Andyjr1515 build Foam rubber is on the top of my list but I need to make sure it will stay in the chamber or it will pop the magnet-held hatch off

While the neck continues to be clamped (after a day, I'm not sure there has been much change - I think I'll be taking the fretboard off over the weekend...), still a few things to be sorted on the body. The built-in battery compartment works well - just need to sort a simple method of stopping it rattling round in its chamber:

The control hatch will be attached with neodymium magnets - 4mm in the body lugs and 3mm on the hatch. Folks tend to spend a lot of time measuring and remeasuring and sorting all sorts of ways of marking which way round each magnet goes. I find that far too much like hard work and so I use...magnetism! First I drill an accurate 4mm hole in the lug to a depth of just deeper than two magnets. I pop a drop of CA glue in the bottom and use a cocktail stick to press a 4mm magnet fully home: I then make a thin ziggy-zaggy packer with some emery paper offcuts: I pop the packer into the hole and drop a 3mm magnet on the top. Because it's magnetic, it orientates itself. I make sure it's level, in line with the 4mm chamber and slightly proud: Finally, I pop a drop of CA glue on the upper face and then place the hatch into the recess and hold it down for a few minutes. I lift the hatch and, all being well, the magnet is stuck on. Three done, three to go: Finally, I wick a teeny drop of thin CA around the hatch magnet for additional security, winkle out the ziggy-zaggy packer and move onto the next one. No measuring, no orientation problems, all 6 magnets in exactly the right place More of a challenge is the thing that I was expecting to be the most straightforward. I noticed when I strung up the bass to check the bridge position that the trussrod had to be adjusted quite a bit to forward bow for the strings not to rattle. When I took the neck off again, I loosened the truss rod to its neutral point and popped the levelling beam on it. To my surprise, there was 2mm of back bow in the neck when the truss rod was fully released - more than the strings would straighten and hence the need to put forward bow on the truss rod when the strings were fitted. I checked with @Happy Jack whether he had found that he had suffered any buzz or rod issues when he was playing it, but the answer was negative. But he does play a lot of basses in a lot of venues, so it is possible - as a number of bass and guitar owners have found this year - that it took on a set during the hot weather and hadn't been played since. If so, as the first port of call, it may well be able to be straightened simply by applying pressure in the opposite direction for a few days and get the maple to remember where it used to be! Then the strings should be able to take over their normal job of trying to get the neck to add a bow, and the truss rod resisting to end up straight. That's in train - this will sit on my spare table for the next few days and see if it sorts it: The clamp has been tightened to put a couple of mm forward bow on the neck - with the truss rod adjusted to be applying no force. It will sit like this for a few days and then I will release the clamps and re-centre the truss rod. All being well, the back bow will have gone. If, however, it simply springs back to the 2mm of back bow, then Plan B has to come into play...which is removal of the fretboard, flattening of the neck and then reglue of the fretboard. Not the end of the world but fingers crossed that it won't need that extra work Other than that, I think it's pretty close. I have some Dunlop flush straplock ferrules on their way, just about to order the knobs, I'll be buffing up the finish in this coming week and, all being well ref the neck, assembling it for final hook up and set up...

When it's fully dry after your final buff-up, do yourself a mockup and give yourself a bit of 'air bass' playing time. It'll tell you which option it wants you to pick. Either will look great (that really is a nice piece of ash) so it's more about how you feel playing it. And no-one else can decide that

Yes - spot on. You're doing a good job on it. So, for folks who were looking for silky smooth satin, it would take just one more wet 'n dry with a small amount of tru-oil and, say, 800 grit and then immediate vigorous buffing to dry it off and create the final sheen. It's then left overnight to harden and buffed again...and that's it! For the Ronseal Hardglaze gloss treatment, it's similar, except that, after buffing, you then leave it for 3-4 days minimum to fully dry before beginning the Ronseal wipe treatment covered above

Yes - that's looking good

Cup of tea with three bags of sugar...

3.12kg according to t'internet