Double bass rebuild - not for the faint of heart!

[The Guitar Weasel]

Neck fit is getting closer - this is all hand tools shaping so it can't be rushed. Looking a bit rasp-rough at the moment ... but lots more wood to come off still. 

 

One issue that has been highlighted is how bodged the previous neck re-glue was and how 'out' the original neck pocket was built. I wondered why the neck appeared to have been glued in without being fully seated in the pocket - in other words glued to the sides but not even touching in a lot of the bottom of the pocket. Well that would appear to have been a bodged attempt to face the neck properly down the centre line of the body. with the new neck properly seated and its mating face at exactly 90 degrees in all directions the neck and the fingerboard (strapped on with tape for the test) point way too far over to the bass side f hole. The whole neck pocket must be out of true with the centre line. The solution is to plane and use a cabinet scraper to deliberately take the back of the heel down on one side - thus pointing the neck/fingerboard once more along the centre line. 

 

 

 

For those into tools - the lion's share of the wood stock removal on this project has been done with the 'rip' side of a 250mm Japanese Ryoba hand saw. I really can't speak highly enough about how good these saws are. Maple is hard - and a bitch to hand saw - but not with one of these. The Ryoba cuts like a sharp breadknife through a fresh sourdough loaf ... so satisfying. 

Edited May 16 by The Guitar Weasel

[The Guitar Weasel]

So while I'm waiting for the neck bolts to arrive I might as well do a bit of tidying up. 

The bottom front edge of the bass had taken some nasty damage to the laminations - but all easily fixable. I sawed down some birch ply down to one lamination and let it in with hide glue and then scraped with a cabinet scraper. I'm not worried about small gaps and visibly repaired cracks - I'll mix some fine powder birch sawdust with glue and fill the cracks. Okay the finish is buggered in this area ... I could touch it in - but I'm leaning towards a full refinish.

 

The end pin hole had been reamed out massively and was also at the wrong taper for the new endpin - it nearly fell into the bass! 

 

 

So I made and glued in a liner from thin mahogany stock

 

 

And I'm using the incredibly slow method of bedding the endpin into the hole by double stick taping sandpaper around the pin ... it works well and is way cheaper than an end pin reamer - still got some to go! 

 

 

I've ordered an ebony saddle to replace this ... er ... 'wood' one 🙂 

 

 

Edited Wednesday at 19:29 by The Guitar Weasel

[The Guitar Weasel]

So this is where we are now - 

 

The neck joint is fully trimmed and VERY tight fitted - it's gone back to the correct depth leaving exactly 27.6mm of overstand as per the original. 

The underside of the fingerboard end to belly is also exactly like the original - this is testament to my grandfather and father's advice measure a job twice - have a cup of tea - then measure twice again - then have another cup of tea to think about if you are actually doing what you need to be doing:  the four measure/two tea method (or coffee if that's yer bag).  

 

So the possible order of the the list of jobs still to do: 

1. Scrape a small amount from the bass side of the neck heel face to correct the slight wonkiness of the original neck pocket that had the fingerboard way off centreline. 

2. Bore the pilot holes in the neck heel out to 8mm and cut the wider area to sink in the cap head stainless bolts and washers.

3. Shoot the face of the neck with a sharp hand plane to prepare it for the fingerboard. There is a verrrrrrrrry slight back-bow ... but I will try to leave a bit of that in to pre stress the neck back a tad to resist string tension.

4. Glue the fingerboard to the neck - hot hide glue, properly warming the neck and fingerboard to extend the 'open time' - and I'll co-opt an assistant for that job as it has to be done fast and right! 

5. I'm pretty set on an access hatch in the treble side cutaway - so that will be next probably.

6. Making the neck inner clamp plate - yep I'm going to try that method: a plate bored and tapped M8 and secured to the inside of the neck block 

7. Fitting tuning machines to peg box and some much needed final neck shaping ... the replacement neck is like a tree trunk! 

 

Then technically speaking the neck can be bolted on, the end pin, wire and tailpiece installed, the bridge shaped and fitted, the nut fitted - the sound post re installed ...

And if I want to I can whack a set of strings on there to see what I have! 

 

Yep I'm going to refinish her ... but I think it's worth putting the old girl back under tension for the first time in I believe over 40 years to make sure she doesn't go BANG before I spend a lot more time making her look beautiful!