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surdo
04-28-2016, 10:56 AM
Luthiers!

I'm preparing to make my first instrument, a soprano ukulele. I'm planning to do it with no power tools besides an electric drill, if I can. This weekend I am going to talk with an excellent furniture maker here in Brasilia. He collects all his wood from felled timber from around the country and much of it is excellent wood for ukulele and guitar building (various types of rosewood, Brazilian walnut etc.). It's often very old too. I spoke to him briefly by phone and he intimated that he can help me out with some wood. When he asked how thick, I said I wasn't sure, but thought 2 or 3mm might be in the vicinity of what I need. He said he didn't think any mill in the city could cut that thin and presumably, not his workshops either. I had to finish the call and arranged to speak to him in person. So to my question:

What is the maximum thickness practical to make tops, backs and sides with a hand plane and scrapers?

Maybe he can cut down to 5mm, I'll find out. Perhaps thicker.

Are there any ways to cut or split thick planks manually so as not to waste too much - at least by a beginner?

I also have a large plank of Brazilian walnut (imbuia) at home that must be 100 years old - would love to use this one day too. It's about an inch thick. Eventually it might be good to get a band saw i guess for cutting thin slabs of wood, but I'll see first if i have any talent for woodwork (at the age 12 or 13 I made a pencil case at school that held together OK, so I have some hope).

An then there's the "pau ferro" tree (iron wood) in the back yard...

Oh yes, and before I start on any nice timber, I'll practice first on cheap stuff.

Thanks!

lauburu
04-28-2016, 11:18 AM
I suggest you make friends with a local furniture maker who has a good quality bandsaw. Turn up on a Friday afternoon with a box of beer under one arm and your wood under the other.
Ask him to cut the sides 2mm thick and the top 3mm. Then sand/ scrape and plane to final thickness.
Miguel

surdo
04-28-2016, 11:53 AM
Thanks. 3mm for the back as well? This fellow probably has the best wood in these parts, a town of public servants and few furniture makers, at least that work with real wood. Maybe I can find a carpenter who can cut the thinner pieces. I don't think the beer thing would work here!

Another question. Do these thin slabs (2 or 3mm) store well over extended periods, or is it better to cut the pieces as you need them?

Cheers

ksquine
04-29-2016, 07:34 AM
Most people make tops 1.5mm to 2mm. 2mm is fine for the back. 1.5mm to 1.75mm for the sides.
You can't really saw wood that thin....most wood I buy comes between 3mm and 4mm. Then its all planes, scrapers, sand paper to get it down the proper thickness

surdo
04-29-2016, 08:19 AM
I see. I saw some blanks for sale that were 2mm thick. I assumed they were cut that thin, but sounds like they had been pre-planed/sanded. So if I can get something close to 5mm, I'll be in business? Thanks

Allen
04-29-2016, 10:08 AM
If his bandsaw is up to the task it's easy to cut very close to the desired dimension. When I get billets that i'm working on getting the very best yield, I will cut them down to 2.2mm so I have just enough material to do a finish pass through he drum sander. In your case a hand plane and scraper.

If it's not a well tuned saw with a dull blade, then you will want to go thicker than that. There is no point in trying to get so close that you drift off the cut and loose a set because it's now too thin.

It's best to cut timber into the thin veneers you are planning on using and store them that way if you plan on building more.

surdo
04-29-2016, 10:53 AM
Thanks Allen. Actually, there's a chance he doesn't have a band saw or things that cut fine as most of his work is a bit on the chunky side. Here's his site, I think he does beautiful work - name is Tunico Lages:

http://www.tunicolages.com.br

Was it you that I read somewhere had a stash of brazilian mahogany? If it was, do you happen to know if it is Swietenia macrophylla? That may be available here as house demolition timber. How have you cut it - ie. do you do radial cuts or anything out of the ordinary?

If you know of any other Brazilian timbers that can be used for sound boards please let me know. From what I've been reading there's a pine called Araucaria angustifolia that gets used on mandolins and cavaquinhos - but maybe not commonly. I'm interested in this one and i think I may be able to get it through normal building supply places. There's also a blonde wood called Marupá - (Simarouba Amara) which can be used as an alternative wood for classical guitar tops. There's another cheaper wood called caixeta that was used a lot in making "violas" - 10 string/5 courses guitars. And Freijó - (Cordia Goeldiana) - which cut radially gives a nice marbled look and has ṕotential for tops apparently.

Allen
04-29-2016, 07:41 PM
Yes, I have a lot of Brazilian Mahogany (Swietenia Macrophylla). I pick through the timber for the 1/4 sawn stuff and then resew those planks.

If you can get your hands on it, grab every bit that you can. In my opinion, there is no better timber to build with.

surdo
04-29-2016, 11:56 PM
Is 1/4 cut wood ideal for all parts of the instrument? From the classical guitars that I've known, I think the sides have shown cathedral patterning, which from what I'm reading means they were plain cut. I imagine that necks, bridges and tops are mainly built from 1/4 cut wood, but that sides and backs might be from plain-sawn wood. Is that correct? Do you have any preferred cuts for the various parts of the instrument?

Also, I went and had a look at my slab of Brazilian walnut, which is actually made up of 4 planks, each 6" wide in the old currency, more than wide enough to make one-piece backs for the tiny instrument I want to make first up. The end grain is parallel to the face however, rather than perpendicular. Would this be suitable for the back? Good for the sides?

PS. Martynas, if you're there, I received your PM but couldn't reply because apparently you have too many stored messages.

Beau Hannam Ukuleles
04-30-2016, 05:31 AM
the answer depends on how much time you have and how strong you are...