Andyjr1515

Trouble is, the fine wires are at the very end of the plate and the cable shielding is too stiff to double back in an S - it would probably do more harm than good. Now it's in, then it's probably OK. Maybe just something for the feedback to Gemini. Everything else is super - the look of them; the presentation (wrapped in purple felt!); the quality of the fixing screws. I look forward to seeing what they sound like.

Don't you think those cutaways add a certain 'je ne sais quoi' ? A bit like cooling vents on a Maserati

The good news is that I've got to the 'make a list of the final jobs' stage. The bad news is that I've only ticked off half of one of them in a morning's work. But that's better than going backwards I've tidied up the bridge pickup chamber, copper-foil shielded and earthed it, fitted it and modded the trial pickup ring to as thin as the chamber allows. Here's the shielded chamber, ready for sorting the fixing holes. I confess I am a little nervous of the un-supported outlet cable coming from the Gemini pickup. It's a heavy cable and those three teeny coil attachment wires are pretty fragile. It's a pity that there isn't any sort of cable secure - I would have thought a simple lacing through a couple of drilled holes in the base plate would have been possible. Still, it seems OK - I just won't take it out again! Also here is the slimmed down trial guard for @ped to see what he thinks. The final version - whatever shape @ped decides on - will have two small pickguard screws holding it in place, one either side of the pickup.

Fully adjustable

Yes - could be quite a bit smaller. I'll trim this one down to the minimum (including width for the fixing screws) while I'm waiting for the black single-ply. Should be able to do that in the morning.

It depends what kind of paint to an extent, but most paints won't like an undercoat of tung oil or similar. If it looks OK just oiled, I would stick with that. If you want a paint finish, it really needs to start with bare wood again, sanding-sealered, primer coated (primer is essential) and then the final colour and clear coats. Most of the easier home finishes are going to be soft enough to fail the fingernail test - even the polyurethane finishes I often use will protect from normal use but will dint relatively easily. Rock-hard finishes are usually into two-part resin and similar territory...much harder and usually come with a significant ramp up of safety precautions, skills and equipment.

And yes - this has some decent mileage. It will be one of the mock-ups I will do as an option with the all-black material.

Both good points and - now I have the inner shape sorted - when the 1ply black blank comes, I will cut two of three outer shapes to bounce off @ped for him to choose whichever he prefers. That said, the first one I tried was, indeed, rectangular with small rounded corners...and it looked like a piece of black plastic trying to cover up a hole This shape (at least in my minds-eye with the radii exactly matching the ones of the pickup) looked much more like it was meant to be there. But, yes, you are right - it can and will be any shape @ped prefers While I'm waiting for the black 1 ply blank, this is now the finished surround for the neck and the same round-ended mock up for the bridge which, in the final version, will have bevelled sides and a pickguard fixing screw either side:

Proof of concept day for the pickup ring/gap cover stuff. For the neck ring, it needs to be thin. The bass has a very low action and so I don't want to lift the pickup ring much at all. My experiment is using some thin plasticard which will create a 0.5mm thick skirt, about 1mm proud of the ring all the way round (when I do the final one). This is my trial, just having an overlap front and back (the finished one will be all round the perimeter): And for the bridge, something like this. This sample is black/white/black - no good as the pickguard is now, after decades of light and smoke, close to ivory and it would clash with the white once the edges of the cover are bevelled. I have a sheet of single-ply black on order that should be with me on Wednesday. Oh - and I will use a set of compasses to get the curves correct for the final version :

I do thank you, @Mykesbass But I know when something is out of my league...

Yes - just flipped over. It's been strung up and unstrung so many times (which is why I always use a 'sacrificial' set for this stage), I'm not surprised that the saddles have started turning over in disgust

Well - my bits box is certainly wide and varied. As I vaguely remembered, I do indeed have some genuine and unused Mustang/Jaguar slide switches. The great thing is that I therefore also have the proper short and threaded screws This is where @ped and I agreed it should go: For the pickguard I drilled the corners of the slot, cut the middle out with a scroll saw and straightened everything up with a couple of needle files: For the chamber, the same as the pickup chambers - hog out with a forstner bit and then chisel the 'waves' straight. This is before I did that latter step. For cable access, I simply need to drill a short hole between the controls chamber and this new switch chamber. And it's in: Tomorrow will be sorting the two pickup ring 'skirts' if I can find the material I'm hoping to use. And after that it should be all of the actual construction work done - it should be then just a case of wiring it up and putting it back properly together

Just catching up. Welcome to the challenges of finishing - it's a rocky climb! The most important thing is that you have a neck and body that fit nicely and the strings and bridge line up! Just reading your thread, there are many things that can affect adhesion of paints (which is why, generally, I don't do paint finishes), but one of them is certainly that many, if not most, manufactured bodies have a residue on the surface and always benefit from a thorough sanding before doing anything. It may or may not have anything to do with the problems you had (did you use a primer?) but I was reminded of this when I saw the tung oil result...it looks surprisingly light coloured. Is that residue of the white paint there too? If so, it might be worth giving the body a rigorous sanding - right down to proper bare wood and then try the tung oil (other oils work OK - Tru-oil; Danish Oil; etc) which might soak better into the wood, darken it and be quicker to dry. The test if you are sanding is to take a clean facecloth or dish cloth, soak it in water, squeeze it out and wipe the surface of the sanded wood. The dampness should darken the wood as the water soaks into the grain. Any residue of manufacturing or previous finishes will show up as light patches. When the dampness darkens the wood and is pretty even, then you know you are down to un-contaminated timber and then you can let it dry before starting the first 'soak in' coats of your preferred finish.

Not yet. If it was a slide switch on the scratch plate, it would make sense for it to be close to the volume knob. I'll have a ponder tomorrow

Out came the scrollsaw and off came the excess pickguard: Unfortunately, @atsampson , I don't think the offcuts are quite long enough to completely fill the narrow, but long gaps. After doing this sort of thing a few times, one is relatively relaxed hitting a 56 year old icon with a Forstner bit...well, definitely relatively And, again using chisels and mallet, the chamber is cut: And it fits! (Big phew!)

Yes - that's a decent thing to try. It is such a small gap it might be 'just enough'. I will try that but if the glue line shows pretty much as much as the gap, then I can always revert to the original thought of a couple of mm skirt underneath the pickup ring.

Hi @Zephyr You are right to be a bit confused - because there is a lot of confusion generally in the guitar and bass worlds about truss rods and shims. So - a quick explanation. Truss rod Its purpose is to make the neck straight. Period. The string tension, when fully tuned up, tries to bend the neck like an archery bow (picture courtesy of Guitarless.com) : - The trussrod's job is to bend the neck the opposite way to end up with a completely straight neck. - Yes - the trussrod adjustment affects the action height - but that is not its job. Shims/Neck angle If your neck is straight, when under full string tension, and the action is too high or too low for the saddle height adjustment to be able to compensate, then - for a bolt on neck - it is the neck angle that needs to be adjusted. And a shim in the neck pocket is what is usually used to achieve that. I always find this the most useful pic to explain exactly what is going on (Not my diagram. It is used quite often by different folks so I don't know who to thank) : Using a shim in the neck pocket is nothing at all to do with bending the neck at the upper frets. Trust me - the neck is never going to bend there from a shim (so yes. your question was quite right) If your action is too high, then you put a shim at the very back of the neck pocket which then lifts the back of the neck and tilts the whole neck down ('down' from the perspective of the above pictures). This lowers the action. Ref the above, Pic 2 is where you are starting from with too high an action; Pic 3 is with a shim at the back of the pocket; Pic 4 is if the shim is too thick and now the action is too low and the strings are pressing against the fretboard) If your action is too low, then the shim goes at the front of the pocket, which tilts the neck up. Usually, it needs no more than the thickness of a credit card and often less. Any material can be used as long as it won't crush (and so cardboard is no good; a slice off a business card is OK; a slice of old credit/store card might be a bit thick but is ideal as a material). Here's a shim that I found, under quite a fancy bass I am working on, when I took the neck off. It will have been put here to lower the action enough for the saddle adjustment to be able to do the fine tuning. It is around 1mm thick and will tilt the neck downwards, which lowers the action. : If the action was too low, then a shim would be put here: So, back to yours: - You want to get the neck as straight as you can to start off with. Truss rod adjusts this. Only measure when the neck is on, the strings are on and tuned up to pitch. - As mentioned above, the simplest way of checking is: Hold the G down at the 1st fret and the 16th fret. At the mid point (7th/8th fret) there should be a just perceptible gap between the string and the fret. If it is hard down on the 7th or 8th fret, then the truss rod is too tight and creating a back bow and needs loosening. If there is a gap, but it is anywhere more than, say, the thickness of a business card, then there is still too much bow in the neck and the trussrod needs tightening a touch Once the neck is straight under string tension, you can then look at the action height. If you can get a decent action with the saddle adjustment, then simply do that. But, if even at the top or bottom of the adjustment range of the saddles the action is too high or too low: - lower or raise the saddles to the mid point of their adjustment range - if the action is too low, try a shim in the front of the neck pocket - if the action is too high, try a shim at the back of the neck pocket

This ^

@ped and I had a discussion about the pickguard positioning. I had noticed that most of the fixing screws were squiffy and, when I took it off, while it is clearly a genuinely old pickguard, I had wondered if it had been replaced at some stage - especially as the P pickup was also at an angle, as with the bridge and bridge pickup. Could it be shrinkage of the original, @ped speculated? Also, as fitted, there was a gap - and uneven at that - between the pickguard and the controls plate. And so, was the control plate original (especially there's an 'extra' screw hole underneath when you lift it off)? Whatever, there was a choice: leave it with squiffy screws; butt it up to the heel; butt it up to the control plate. And it was that last option that @ped decided - leave a larger gap at the heel end but butt it up to the fitted jack plate: And only two holes lined up...the rest each being around 2mm out. And guess which those two were? The two were the ones next to the control plate And so @ped was absolutely right. Almost certainly this is the original scratchplate AND controls plate and the scratch plate has indeed shrunk that much. But what about the squiffy P-pickup? Well... the wood underneath isn't squiffy - almost certainly that angle has resulted from the same problem. This was further supported by the fact that the P pair was hard against the plastic when I tried to lift the pickguard off. Everything else supports it - the pink stains on the back of the scratch plate, the original non-yellowed pearl where the original thumb rest was. All the screw holes except two were plugged with B-B-Q skewers (no need for with-grain large plugs here) and re-drilled and screws re-fitted nice and straight. And then I could position the neck pickup ring. It covers most of the P-pickup hole, except for the wedges left by that twist. Position was checked against the centre line of the fretboard dots... ...and couple of fixing screws fitted so I don't lose the position. Finally, the chamber shape marked for cutting out with the scroll saw in the morning

You’re right @fleabag Can’t find one anywhere.

It took a couple of goes to get the bridge in the correct position (good thing about there being so many fixing screws was that I only needed to use two for the first trial - enough for being able to fit the strings straight but un-tensioned. Those first two screw holes will need to be re-plugged ) but got there in the end in terms of the strings lining up correctly with the fretboard dots: And with that done, I could start on the bridge pickup chamber. Those who have followed my previous threads will know that I detest routers and certainly wouldn't willingly use them on something as old and fragile as this. Instead, I start with drilling the corner radii and positions of the pickup base plate and scribe a line tangential to the two corners: Next, I rough out - for a full humbucker I would use a Forstner bit but, for this extension to the existing Jazz p/up chamber, just a brad-point drill: And then next, out come the sharp chisels and mallet: Don't worry - the red next to the chisel is some silk from the test-strings I use for the on/off/on/off malarkey that is necessary for this kind of work. The blood from my missing finger is out of picture on the carpet And twenty minutes later, we have a chamber: Finally, a quick restring to check it does actually line up. Phew! So tomorrow, I will re-plug the two erroneous bridge positions, take out the P pickup and start thinking about both the fitting of the Thunderbird-ish neck and the surrounds to hide the gaps.

For plugging the drill holes that I'm just about to make for the new bridge screw holes, dowelling is no good. Why? Because the grain runs along the length of a dowel and the circular bit is therefore end grain - which has insufficient screw-pull-out resistance. And so I use a plug cutter on some similar strength/softness wood to the body. For this one, I'm using mahogany which is closer in hardness to what is probably an alder body than, say, using maple. With a following saw cut, it releases the 'across the grain' dowels: And the plugs are in waiting for the wood glue to fully set. All being well, tomorrow I will be able to drill to refit the bridge in its straightened position and then I can string it up with a couple of spare strings so that the pickup positions can be accurately marked

And so, on the basis that everything affects everything, before I start plugging and fixing the new bridge, are the pickups chosen in @ped's concept going to fit? The two pickups that @ped got sent to me are a hot Ric-ish Gemini Pickups 'Surfrider' for the bridge and an equally hot Thunderbird-ish Gemini Pickups 'Degenerate' for the neck Here they are in their approximate positions: The bridge Surfrider will need a sympathetically chosen surround made as it is slightly narrower than the J and there is the base plate to hide. It will be hard against the bridge as with the original J. The ring with the Thunderbird so very nearly covers the existing P - it only fails because that is at the skewed angle and that leaves a teeny gap. I will make a thin plate under-ring just a couple of mm larger than the metal ring to hide the gap. There will be switch(es) - Mustang slide switches if they will fit - for coil tap. And that should be that! Just got to do it

And so to that bridge. Using my long rule running up the fretboard, I positioned the bridge square with it at the correct length. Then I checked the two string runs from the nut slot to the saddle grooves: So - did ANY of the bridge holes line up? One! The far left above the E saddle. And only one of the through-body holes (the A) although all of those will be usable. It wouldn't have made too much difference if none of the screw holes had lined up - but it meant that, without any plugging and redrilling, I could secure the bridge to stop it sliding about... ...while I double checked and triple checked and quadruple checked, etc, etc, etc

It does...but no