dazzaman's Former Challenge Build - the Jajatecaster

Thanks for all the comments and advice/support. I will go with what I have and keep my fingers crossed.
Trust me, my brain ache has been affecting me for ages on this. And is a lot worse than anyone elses...

 

Okay, hopefully I can sit down and get all the wiring done on the weekend.
In the meantime I have been working away on the nuts.
I got one of the large Stewmac bone blocks (possibly intended more for bridges than nuts?) and passed it through the thicknessing setup.


Note to self: when passing it through in future don't use such a large bobbin...

Once done I ended up with my blank.


I then cut the blank so that each nut was the right length.


Then marked the string positions with the Stewmac gizmo, and did an initial cut with a saw. Which admittedly does look very much like the previous image, but there are saw cuts there, honest.


Though not photographed (at least, yet) I have fitted the pickup covers into the pickguard and drilled into the body for the pickup height screws, put the bridge posts in the body, and have drilled holes for the string grounds.

So, still need to rough out the nut slots, wire up, attach pickguard, attach tremolo units and then I can attach the necks and be on the home stretch.

 

Got a little bit of time to finish the roughing of the nuts.

Used the fret files, along with feeler gauges, to get the slots to the correct width and depth.


And then sanded most of the excess of the top of the blanks.


Once the strings are in place I will ensure everything is okay, polish the slots and get the top to the final height.

 

Hi James - not completely. There is definitely an issue of non-adherence when doing polishing. There are three fairly small spots which are not taking a polish whereas the rest of the back is perfect. None of these spots are where the problem was before.

So, I know whatever it causing it can be solved, I just don't know what is causing it at the moment. I am not willing to strip the back and go through a whole process again to find the same thing happening ad infinitum. So what I will do is go through my process again and try step by step to see where the problem is. I will veneer a panel and divide it into sections and remove steps to try and isolate it.

It seems to be an incompatability issue between the rubbing compound, scratch X and zymol, perhaps related to whatever surface I have on the wood (which will either be CA or Poly).

In the meantime I will get it finished other than that, knowing that once I have isolated it there should be a fairly easy fix.

 

Silicon contamination was my first thought, and I remain convinced it could be the problem. I will take a photograph of the worst bit and post it when I am back in the shop later. It is funny that it is isolated "puddles" of missing finish (sort of like looking at a lake on a map). I would have thought that silicon would affect all of the finish. Other parts, like the necks, have had no issues at all. And everything has had exactly the same finishing procedure.
But, it is like I was applying one part of the finishing process and it was taking off everything that was underneath it. I don't know if the rubbing compound has silicon, it doesn't say, but you are right with scratch X. I was advised that there was not enough to cause issues with hand rubbing, but that might well be mistaken advice.
The instrument will be playing before I resolve it, and will be done properly rather than left in that state, I have spent too much time on it to leave it looking a bit reliced... On the other hand, the build has also been a fantastic experience in teaching me things that I will do differently next time, while still looking beautiful to those who don't see the issues that I do.
I am also going to change my finishing technique away from hand rubbing as a result. Probably not to a floor-fixer buffer, since I don't have the workshop real estate for the limited use it will get, but definitely to a motorised system (I am thinking a car buffer at present). I will re-look at what brand I use as well. 3M must be available, at least online, though I have never seen it in shops.

 

So, an image of the back showing what the problem is.


And a closer one of the worst patch/


It looks as though I have rubbed right through the finish, but there was definitely some there when I started the rubbing process after going through with wet and dry paper.
It appears (from the first part of the experiments) that the Swirl X is the issue (I have probably said Scratch X above - I have both). It goes on and then applying the zymol as the final polish seems to cause it to take the coats off as I rub it in. Zymol itself does not (as far as I can determine) have any silicon it it.
It appears a fix can be using CA then wet and dry finishing to 2500 grit, then applying zymol only, so I shall next try that on a fairly unnoticeable part and see if I have success there as an approach.

 

And further of the weekend's activities - started on the wiring.
Thanks to whichever genius it was who first suggested using a routing template as a pickguard cradle.

The masking tape marks the position of the edge of the routed holes.

Started with an easy part...

...and then did a harder part.
First without any wires.

and then with.


A question for those who ever actually read this far down a post...

In post #216 I show my ground wires including one from the rhythm circuit volume to tone to the ground star. Now I am wondering. Since the two pots are attached to a metal plate, does that introduce a ground loop, and would I be better taking it from just one of the pots?

 

Got a bit of time over the weekend.

So, I managed to complete the wiring...


The tape is there to still act as a guide for where the holes are in the top. It was rather useful, as it took quite a bit of time (and a little bit of extra cutting away with a chisel in places under the pickguard), but I eventually got everything fitted on the body...


For those that might be wondering, the weight of the body, with the pickguard having its electrics and the hardware comes in at 9.4lb.

Then a very little bit of time last night got everything put together.



Unfortunately I didn't get a chance to put a string on and plug her in, and I am now away for a few days at a conference, but I hope there will be some noise (of a musical nature) at the weekend
I did get to weigh it, though. Comes in at 13.2lb :neutral: