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Hello wood working gurus! I’m a woodworking neophyte and would like to do a project with my Dad- I’ve built lots of parts instruments, so hoping that a bass body won’t be too hard= Long scale, 34 inch bolt on- Buying everything except the body

I could use input on a wide range of topics- Concept follows and totally open to ideas!

1. Wood- I have a eucaliptus trunk that has been drying for a few years and would like to cut into planks, join and make a bass body from it and wonder if this makes sense?

a. Eucalyptus Trunk is roughly 12’ long * 5”circumfrance
b. Cut into strips
i. Maybe 2”*2”*2’
ii. End up with a solid hunk of wood that is 2 inches thick
iii. Band saw shape and rout as if we were making a solid body
iv. My Dad has a lot of joining and non-guitar woodworking experience
v. Does this make sense so far?

2. Design-I understand that eucalyptus has great tone, but is very heavy, so we were thinking
a. Bass sized, L5 shape with a flat top (would look something like a Rumblecat)
b. Rout out the wings from the backside
c. Keep the complete center section from neck pocket to end pin intact to support neck, bridge, pups
d. Will end up with 2 symmetrical, routed sections on either side of the center
i. Bevel those edges and cover with plastic covers that are significantly larger than the average back plates
e. Does this make sense?

3. What would it Sound like?
a. Technically it won’t be a hallow body, but I image it will have more thump and less sustain- like a chambered electric?

b. I imagine eucalyptus is bright

c. I imagine that this design might do well with 3 passive pups
i. Neck mini-humbucker, maybe get a somewhat thin thump similar to a 60s hollow body
1. The size would be nice
2. Or alternatively, a big Gibson EB3 L neck pickup that would be less bright?

ii. Pbass center, normal placement for somewhat traditional Pbass thick sound
1. I’m a jbass nut and could imagine J pup in the center could work- But trying to make up for the ‘hollow’ nature and image the pbass pup would be the only ‘heavy bottom’ pup

iii. Jbass bridge pup-
1. As I said, I’m a J nut and Joco rules, but if eucalyptus is bright, this might be rather bright

iv. Probably a standard Jbass bridge

v. 3 vol and master tone

vi. Will probably go with a 5 position blade
1. Jbass bridge
2. Jbass + Pbass
3. Pbass
4. Pbass + Neck
5. Neck

d. Does this make sense and what would it probably sound like?

4. Questions
a. Appreciate feedback on all question above

b. How deep should we rout the wings?
i. Leave ¼ inch of top?
ii. Is this strong enough and the top isn’t really acoustic, so no reason to go thinner? Any reason to go thicker

c. Controls- Would have to route controls sections much farther to allow pots and switches to make it through the top- I guess these are standard thickness, and we are depending on the strength of the rest of the top to keep control cavities from collapsing

d. How wide should the sides be?
i. I image that we would route the wing cavities to leave ½ sides?
ii. Would this be strong enough, considering that the center section will be solid?

e. Ideas on a free design app?
i. Google markup?
ii. Something better?

Appreciate any additional ideas, thoughts-

Eucalyptus has a giant amount of variation within the species. Wood ranges from less dense than mahogany to harder than the rosewoods.

I think in this case - it's critical to size up what you have in your hand. Figure out the density - where it shakes out and work accordingly.

The bigger issue with working it is cracking to pieces and twisting like crazy if its not properly dealt with prior to and during resawing.

Last - check your measurements. A 5" circumference is like a 1.2" diameter. You would be better off using that as a walking stick or something like that.

Thanks Truck John!
Yes, I meant 5 inch diameter;)

How do I check density?
Cracking twisting- Is this a moisture level issue?
Would a photo of a log help?

Big thanks!

Can't help with your questions but I want to see it when you build it!

For density - take a small strip of the wood. Dry it out good. length x width x thickness = volume.
Weigh the dried wood.
Weight / volume = density.

A quick check is to see if it's heavier or lighter than the same size piece of oak....

The usual orange stuff we run across here growing in the USA runs somewhere between soft maple and oak. It's great stuff once you get it milled and dried properly. Easy to work, takes glue fine, and stable enough.

In the mean time - get the ends coated with wax and strip all the bark off. That will give you a little more time to get your act together on milling it.
General rule of thumb is 1 year air drying per inch of thickness.

Thanks

Thanks so much! Will let you know test outcome in a week or two. Cheers !

Thanks again TuckJohn et al-
I’m moving forward on my project, but definitely getting some conflicting eucalyptus density measurements and wonder if my math is bad and would appreciate any input!
Here's what I did-
1. Test branch-
• Created a .5*.5*6 inch strip
• It weighed 41g
• I used the microwave defrost bag and dry method shown here
o http://haslip.info/woodturning/microwave.html
o I was amazed how much condensation was driven onto the baggie wall each time
• after 7 cycles (.5 min defrost, 29 minute of rest in the plastic bag) weight stabilized at 38g- around .10 water removed sounds about right?
If I did my math correctly, that translates into-
• 26.032154626 Lbs/ft^3
• Comparing that to other woods on this chart, http://www.engineeringtoolbox.com/weigt-wood-d_821.html it appears that this strip is about the same or less dense than cedar?
• Probably Not dense enough to hold screws?

2. Considering that I might have done something wrong, I did as you suggested with a trunk log and then calculated green density-
• Stripped husk/bark
• Painted ends to dry
• 6inch diameter *23.5 inches long
• Weight =23.2lbs
• Lbs/ft^3=
23.2/.3846724=60.3110595

So this is the other end of the spectrum isn’t it? The chart for 60.3 greenwood (at the same link) appears more dense than walnut and a bit less than oak? Is my math off somewhere?

Questions-
1. Or is it possible that Eucalyptus trunk wood is much, much more dense than the branch that I used for my strip?

2. I wonder if is worth ripping one of the green logs into 2*2*20 inch plank to see if they survive the microwave method and if they appear joinable?

3. If joinable, for a solid body, I’m assuming that plain sawn is just as good as quaretersawn?

Open to all ideas and thanks in advance!

It's probably in the heavier range...

I would not do the microwave method for big chunks... Very likely to dry way too fast and ruin the wood. Crack it all to pieces or risk making it honeycombed on the inside.

Your best bet is to saw it into 1" slabs, paint the ends, stack and sticker and then just let it dry normally. Fall 2017 you will be ready to see how things are going.

Thanks Truck John- I guess we'll know what we have when we get there, eh?

A 6" log is not large enough to make stable wood for a body.

uh oh, we were planning on 2*2*20 inch planks and I think you are telling me that won't work-

Maybe we have a whole bunch of carving wood for someone who carves;)

I say try it out anyway. This is an electric guitar body... Worst you will be out some time sawing up the lumber.

Instead of the 2" - Slab it at 1" thick and go from there.
Wood takes 1+ years to air dry to a usable moisture content. So if you slab it at 2" - you will be waiting for minimum of 2 years before you can use it. Also - with a log that small - at 2" thick, the center slab will be about all that's useful. That puts you at risk of an all or nothing proposition.

Slab it at 1" and your top and bottom slices aren't useful - but you get a couple in the middle that probably will be... And you can start looking at it after a year.

On the length.... Just leave it full length. You will lose wood on each end to drying defects. The more ends and shorter pieces you start with - the more you lose. Cut it to length after its dried and you decide you still want to do this.

So... Have you gotten the bark off it and the ends of your log painted yet? Chop chop. Bugs and rot wait for no man.

First of all, if the trunk has been lying around for a few years with bark on it will likely have checks running through out it and possibly some fungal degradation. Secondly, this is a REALLY small tree. That small of a tree just does not make for stable lumber. Most guitar making wood comes from trees that are at least 24" across. You can make solid bodies using a butcher block construction, meaning out of a bunch of small pieces. But first you will need to cut the trunk up and see if it is solid with no checking or cracking. But I think you will have a hard time even making 2" x 2" pieces of lumber out of a 5" diameter log. Because if you want this to not crack in the future, you HAVE to avoid the center of the log.

Ok, sounds like I have a lot more to learn-
1. Yes the logs are cut husked and ends painted- thanks for the instructions

2. I see the advantage to cutting 1 inch, however the bass needs to be 1 3/4-2", so we would end up with 2 layers of wood glued together and I guess that would be stronger than a single 2"?

3. However, I didn't realize that the center wood cant be used- if this is the case, it's going to be a real challenge not to include the center

Dad wants to mover forward and rip planks next week based on the 'can't hurt to try' method so I guess the questions are
-1" or 2"
-How much to avoid center

Also, I think I remember reading of proper ways of stacking planks to dry, any specific input?- Also thinking if some good amount of weight on top of them might keep a 1" plank from twisting?

Generally the very center isn't used. But in the case of such a small tree - there isn't the risk of unstable or crushed grain like there is with a very large tree. If you do decide to use the heart - make sure it's well boxed. I would greatly prefer to rip down the heart I might take out the center 1/2" to reduce the risk of cracking or splitting down the pith.

For a dry run - get yourself some Douglas fir 2x4's and joint it up to make a body.... That will probably give you an idea of the weight.