Double Bass Build

[hillbillybass]

Since I'm no longer a new member and my double bass project has been going for a year now, I'm continuing the 'New member New build' progress updates in this thread.

Anyway, the build is still moving forward...slowly...and with plenty of um... "excitement."

In short, after a few weeks of neck mortice woes, I'm onto shaping the sides of neck block number four.

Why am I trying to cut a mortice at this stage? Well, both Harry Wake's and Peter Chandler's double bass making books suggest this is when to cut the mortice before gluing the ribs to the neck block. Chandler doesn't give a reason for this, but Harry Wake says it is "convenient."

If there's one thing I can do, it's follow directions. However, being a self taught beginner at this, with limited cash, and very few power tools and machinery, etc, I've mucked up three attempts so far. It's just not something I can do with absolute accuracy yet using only hand tools. And I certainly can't get the levels of accuracy needed to make it a hot hide glue joint that will hold.

So I called a violin maker friend of mine who also builds double basses for advice. He told me not to cut the neck mortice until I've finished carving the belly and have that glued on. That way I can get the neck properly centred, and overstand height, f-hole positions, etc, correct.

So, after chasing my tail for a few weeks, I've just shaped the sides of neck block number four and will steam bend the ribs and glue them to the neck block next week. Then I'll start on the belly.

In the meantime, I'm reading up on routers, etc, and seeking advice and other's expertise on whether this might be a possible way for me to achieve an accurate fit at the neck joint.

If so, what size router am I likely to need to make a mortice of 35mm deep X 60mm at the top and 40mm at the heel? How many watts, rpm, etc? What can I expect to have to (save up and) spend? Will a decent quality mid range one do the job or do I need a 3 horsepower 2200 watt elephant gun of a thing? What sorts of jigs, etc, have others built for this kind of thing?

I've never used a router before and there seems to be quite a variety of them. Also collets, bits, etc, etc. Reading up on them is mind boggling.

Cheers,

Michael (hillbillybass).

[Dave M]

As an amateur guitar builder I sympathise - I have made rather more necks than I have guitars!
It is also a truth that there is rarely one 'best' way to do things. Depending on tooling and skill levels, what suits one person doesn't work for another.

Routers. These are incredibly useful tools for woodworking in general and instrument making in particular. As you say there is a huge range but they basically divide into quarter inch and half inch diameter for the cutting tool shaft, obviously with the higher power in the larger sizes. There are also things called laminate trimmers which are just a subclass of 1/4 inch routers - often lighter, easier to grip and very useful.

There is a mail order tool company in the UK called Axminster tool etc, this is a useful site because they sell a good range of routers and you can get a good feel for the range of sizes, prices etc. You may well have a similar shop in Oz. I find it useful to do the research initially this way before even going to a tool shop.

The usual principles apply - cheap ones will work but not very well and not for long. You can spend an absolute fortune (without mentioning Festool by name!) but there is usually a sweet spot where price and performance suit. With routers one of the key things is runout, ie how much the shaft wobbles. Some are much better than others.

[Allen]

My favorite is a 1/4" laminate trimmer and I own 5 Makita's all set up with their own dedicated bit for the particular job I need them for.

However with a 35mm deep cut you are more than likely better off with a 1/2" router over a 1/4" one. If it's just very occasional use then you don't need something that is over the top. The usual contenders found at your local hardware store will do the job.

For deep cuts like this you need to go in stages. It may mean that you have two templates. One that will allow you to use a straight bit to remove the material in the middle of the dovetail to full depth while staying away form the very edge of the sides. And then the final one where you use the dovetail type bit to do the clean up pass on the sides. It means less stress on the cutters and router, plus you get a feel for the job prior to the very critical final pass.

[Dave M]

Allen quite.

I didn't want to frighten Michael too much by admitting just how many routers I have stashed around the workshop! Including the ones that go in the makeshift router table. Also jigging is such a huge area there are books on it.

However for someone starting out it is worth knowing that with even the simplest of jigs and a half way decent router a whole range of tasks become possible to do accurately and quickly.

[kiwigeo]

When buying routers watch for shaft run out and also secureness of the depth stop assembly. If you plan on doing some serious hogging out then you'll want a bit of grunt. My first router was a British made Trend T5. It's still my main go-to machine. Laminate trimmers are great for binding channels and other moderate sized jobs. One thing I like on my machines is a soft start. The Makita laminate trimmers I've got don't have this feature and when you're starting a binding channel cut the machines have some serious kick back when they start up. Ozito.....if you want an expensive door stop for your workshop door then get one of these. If you want a reliable power tool then don't touch them with a barge pole.

+1 for Allan's advice on hogging out with a straight cutter before finishing up with a dovetail cutter. I generally use a big machine with a 1/2" shaft for doing my dovetails.

[hillbillybass]

Thanks for all the great advice fellas, I appreciate it.

I'd already figured out that routers are a bit like tattoos. You get one, and then another, and before you know it...

At the moment I'll probably only need a router for one job i.e. cutting the mortise, but I imagine once I've got the hang of using it I'll probably see the potential for a lot more applications...and for more routers! Down the track a trimmer or a dremmel might be good for purfling channels, inlay, etc.

And I'm staying away from Ozito. The only Ozito I have is an almost new table saw my neighbour gave me after using it for one job. I'm thinking I might use it for cutting the heart wood out of the boards I'm using for the belly (50mm X 300mm x 1300mm) before planing them for joining. I'm yet to use it, but if it's crap it'll go out on the nature strip.

[hillbillybass]

Progress Photos. I got the last rib glued in and clamped it today. Bastard of a job to self teach, but I know how to do it now. Also got the boards for the belly planed and joined. Now just waiting for glue to dry.

[hillbillybass]

Been a while since I posted. The Macrocarpa boards for the soundboard didn't work out because they had two
large unstable knots in critical places. Chalking that up to experience.

So I'm looking for new double bass sized boards to use for the soundboard. No luck so far, but I'm wondering about using old growth close grained douglas fir if I can find clear cut boards with no knots or splits, etc, that are big enough for a double bass soundboard.

Otherwise maybe Hoop Pine if I can find some that's big enough. I've wondered about California Redwood too,
but maybe it is too soft for a double bass? Also Western Red Cedar, which is also soft, but which I know has been used successfully by other double bass builders.

In the meantime, I've bent and glued in the first set of internal and external linings. The internal linings are cut from old quartersawn Kauri floorboards.

The external linings are cut from old quartersawn Tas Oak floorboards from the stage area of a local community hall that were offered up as 'firewood' when the hall was renovated.

[hillbillybass]

I haven't posted in a while, but the build is slowly progressing. Here's a few progress photos.

[simso]

I do like how you have approached the build, with inner cross supports for the build and so forth, extremely neat.

Will be impressive when finished.

Steve

[lamanoditrento]

The proportions boggle my mind. Also really interesting that you add the purfling lines before you carve the rest.

[blackalex1952]

Sounds like you got the bug, brother! Or will soon have it! So buy good tools, one step at a time as you build. One can always sell good tools and pick good ones up second hand, if they have not been worn out by tradies! Go for home handymen who have moved on for 2nd hand is my opinion. I have never gone wrong with Makita, they now have a soft start trimmer, but you need the grunt, so look around for a quality soft start powerful trimmer. The next expense will be router bits then re sharpening costs so buy good quality bits as well. A word of warning, practice runs first, and make sure the collet chuck has no debris in it each time you load a new bit! All the how to stuff is on you tube if you look these days...Do you use Japanese back saws? Well worth the investment as well, they cut on the pull stroke and cut fine and straight as well as having replaceable blades. Might solve the problem without a router investment. Jigs for them are easy to knock up if you read about how to use them and practice first.
Cheers, Ross

[hillbillybass]

Thanks for all the great encouragent and advice fellas. I appreciate it. I'm still very much a novice and I've made heaps of mistakes (and running repairs, etc) but it's all part of the learning curve. And the proportions do boggle me at times. Sometimes it feels like I'm building a boat!

I think I do have the bug and I'm patiently buying up good tools as I can afford them. The Arbortech and Makita angle grinder were the last ones I bought with money I earned from a wedding gig earlier this year.

The purfling is a little rough but I can live
with it. I'll do better on the next build. Meanwhile I've just started on the next big task - carving the outer arches on rhe soundboard.

[matthew]

you are probably well advanced by now but i’ll offer a few tips for next time

We commonly use a slot cutter router bit to establish an even edge thickness by registering the router base at the back of the plate.

purfling usually goes in after the arching is carved and the outline finalized on the rib garland. often, purfling is done when the top/back is glued in place!

establish your long arch shape first, then carve upwards from the edge of the plate to meet the centerline. this gives nice even curves.

i cut the neck mortise with a japanese saw before gluing the top or back. a router is hard to manage up north there and you can screw up very quickly. and you still have to cut out the mortise by hand near the button. tricky!

if you are doing a flat back you might consider using my responsive bracing system which I think is a big improvement in the traditional ladder bracing. there are details on my website.

[hillbillybass]

Thanks for your suggestions Matthew. I appreciate it and will follow them on the next build. The soundboard is already arched and I glued the bass bar in this week. Regards the neck mortice, I'll take your advice and cut by hand before gluing on the top and back. Currently working on completing the neck and scroll Cheers.