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This has already been seen on other forums, but for those who haven’t seen it and might be interested, here it is.
I know that the ABG is a great idea that doesn’t work, but I decided I’d like to make one anyway. I already have one (a Furch) which is better than any other I’ve found in a music shop and I thought if I could make one as good as that I’d be quite happy. And then, who knows, I might by some flook find the mystery ingredient and make an even better one?

So having decided, I also decided to include almost all the ‘bells & whistles’ I could think of. The names in brackets are the people I ought to thank for their ideas or help (whether they knew it or not). So the bells and whistles are:

Offset upper bout sound hole
Access panel where the end graft should be (Kent Chasson)
Sound port (Al Carruth)
Wedge shaped body (Linda Manzer)
Spline curved, not domed, front and back (Howard Klepper)
Carbon fibre tubular struts supporting the neck block (Rick Turner, Mark Swanson….)
Fully adjustable neck (Mike Doolin, Mark Swanson….)
Cantilevered fretboard extension (Rick Turner)

I must also mention R M Mottola whose plan I started with but deviated from quite a lot as I went along. If you haven’t checked out his excellent website you should.

http://liutaiomottola.com/

You can click on the photos for a better view.

The full frontal


A bit closer.


The back. Nothing extraordinary but it looks nicer in reality than it does in the photos. You need to move it a bit so that the light reflects off the wood. It’s just plain Honduras mahogany from Larry Davis but has a lovely shine.




Quilted sapele rosette from Uncle Bob. Doesn’t quite twinkle as much as I thought it would. One of the mistakes I made along the way was to make the sound hole just big enough to get my hand through, forgetting about the 2 CF tubes just inside it. Good job there’s an access panel!

The sapele headstock veneer (from Uncle Bob) does twinkle though




The sound port and the cantilevered fingerboard extension. I made the fingerboard flat. I know that some bass players prefer a flat fingerboard so I thought I’d try it. One of my stepsons is a bass player and he tried it out. After a while I asked him if he noticed anything strange about it and he said “no”. He hadn’t even noticed it was flat.
The finish on the neck and headstock is Tru Oil. The body is my first attempt at French polishing (thanks to Colin Symonds for his help). I’m quite pleased with it for a first attempt.


I didn’t do such a good job of the Z-Poxy pore filling on the sides, so it’s sunk a bit, but the rest isn’t bad. Who says you can’t get a gloss finish with Tru Oil? The rosewood plug partially hides the head of the Allen capscrew which holds the neck on as well as adjusting the neck angle (i.e. string height).

A good view of the ‘Manzer wedge’ and the Chasson access panel. A big thank you to Kent who was very generous with help and advice.


I don’t know where you can get bridge pins for basses so I made some.


This shows how the access panel works. The bits of thin plywood stuck to the aluminium channel take up almost all the space between the channel and the panel so as not to stress the panel when it’s assembled. The channel is just wedged in placed and can be removed to give clear access. Thanks for looking.


So did I succeed? Well, all I can say is that I’m really quite pleased with it. It certainly sounds as good as any other ABG I’ve tried (as good as the Furch) and better than most. The bottom E is just a little bit weaker than the others, so I suppose I haven’t discovered the miracle ingredient, but I’m thinking what I could perhaps do to improve the next one. Multiscale perhaps, to tighten up the E string a little?

You must be the original toothless budgie (what sucks seeds)
That looks like some project you've put together.
I'm well impressed Dave, and you have every right to be pleased with it.
Can I ask how may coats of tru-oil did you use the get that gloss, and I take it that it was buffed finally.

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Thanks Colin (toothless budgie took a while for that to sink in!).
Can't really remember how many coats of Tru-oil. Quite a few at any rate. Then I think I went over it with 1200 Wet 'n' dry and shone it up with Brasso. You have to leave Tru-oil to harden for quite a while but, once it's hard, it will buff up to a high gloss.

This is great.


Why is this ?

A six string version of one of these is on my list to build. I saw one on YouTube the other day and figured there must be a way to make it withstand the string tension.

Fantastic Job Dave. The elements all come together. I'm assuming a 34" scale? What are the body dimensions if you don't mind me asking? Any pics of the inside? Sorry, I'm doing a couple right now and looking to shamelessly steal good ideas

Did you do any reinforcement/bracing to keep the body from folding itself in half? I had one do that and ended up redoing it with carbon fiber rods from head to center bout, and tail to center bout. Held up better after that.

That build looks really good...nice work!

Why doesn't it work? Well I suppose it all comes down to size. If you want the sound of a double bass you have to build a double bass. What you get with an ABG is a lower pitched guitar with an E string that's a bit on the weak side. That's Ok if that's what you want. I've tried ABG (bronze wound) strings a couple of times but I really prefer the sound of D'Addario flat wound Chromes.
I don't know much about the Kinal Kompact bass but I can't imagine it having much acoustic volume. Short scale, small body and bridge position are just 3 of the reasons.

Yes Darrel, it's a 34" scale. The body dimensions are:
Length 540mm
Upper bout 380mm
Waist 270mm
Lower bout 450mm
Depth 150mm max. 110m min.
I did a blow by blow account of the construction on the Luthier Community forum with a lot of photos. You can find it here, carbon fibre tubular struts and all:

http://www.luthiercom.org/phpBB3/viewto ... =20&t=1487

Thanks all for the nice words.

Thanks much for the info Dave. I've signed up with the luthier forum, just waiting for an activation reply.