Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Thu Dec 12, 2024 12:45 pm


All times are UTC - 5 hours


Forum rules


Be nice, no cussin and enjoy!




Post new topic Reply to topic  [ 14 posts ] 
Author Message
PostPosted: Sun Sep 03, 2017 3:27 pm 
Offline
Cocobolo
Cocobolo

Joined: Thu Mar 17, 2011 1:39 pm
Posts: 124
Location: France
Hi,

I've been given some very old gabon ebony, since it's often difficult to see the grain orientation on ebony, my question is: in general is it really important for an ebony fingerboard to be perfectly quartersawn?

Image

Image

Thank you

Q.


Top
 Profile  
 
PostPosted: Sun Sep 03, 2017 4:11 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Wed Feb 20, 2008 7:15 pm
Posts: 7381
First name: Ed
Last Name: Bond
City: Vancouver
Country: Canada
Focus: Build
Status: Professional
In general, yes. Flatsawn Ebony can have a nasty tendency to cup, and at 1/4 thick has quite a bit of power behind it, so it can cause problems.

The good news is, with the log half in your picture, you should be able to easily identify the grain orientation and cut accordingly. Hope it's nice on the inside!


Top
 Profile  
 
PostPosted: Sun Sep 03, 2017 6:28 pm 
Offline
Cocobolo
Cocobolo

Joined: Mon Mar 17, 2014 1:27 pm
Posts: 380
First name: john
Last Name: shelton
City: Alsea
State: Oregon
Zip/Postal Code: 97324
Country: usa
Focus: Build
Status: Professional
Wow! You're lucky to have that billet. Many years ago I bought two logs from Gilmer Hardwoods in Portland, Oregon of Madagascar Ebony and sawed them myself. The dust turned the whole shop black even though I had dust collection on the resaw. It's the best ebony I've ever used and I still have several fingerboards of that lovely stuff that I've hoarded for special builds. Why are you worried about "flat sawn" just be careful setting up your bandsaw and if necessary saw in radial passes. You'll end up with beautiful quartered fingerboards. What a find! That stuff is like gold.


Top
 Profile  
 
PostPosted: Mon Sep 11, 2017 8:51 pm 
Offline
Mahogany
Mahogany

Joined: Tue Jan 26, 2016 10:59 pm
Posts: 54
First name: Jonny
Last Name: Fifield
Country: Canada
Focus: Build
Status: Amateur
I too have wondered about this.I see more and more flat sawn gabon boards from the smaller factory brands as time goes by.

I thought that movement in gabon would be minor because of the density of the wood itself,as long as it's well dried.

_________________
"Practice enough till the results aren't hopes but expectations" forum member Peter Havriluk


Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 1:39 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Fri Jul 10, 2009 4:44 am
Posts: 5505
First name: colin
Last Name: north
Country: Scotland.
Focus: Build
Status: Semi-pro
Gabon Ebony Shrinkage - Radial: 8.3%, Tangential: 11.2%, Volumetric: 19.6%, T/R Ratio: 1.3
For comparison, the neck wood perhaps is Hog - Radial: 2.9%, Tangential: 4.3%, Volumetric: 7.5%,
EIR - Radial: 2.7%, Tangential: 5.9%, Volumetric: 8.5%
African Black Wood - Radial: 2.9%, Tangential: 4.8%, Volumetric: 7.7%.

_________________
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.



These users thanked the author Colin North for the post: dpetrzelka (Tue Sep 12, 2017 9:16 am)
Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 5:02 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Tue Mar 01, 2011 1:32 pm
Posts: 3470
First name: Alex
Last Name: Kleon
City: Whitby
State: Ontario
Zip/Postal Code: L1N8X2
Country: Canada
Focus: Build
Status: Amateur
Looks like ABW is a near perfect match for mahogany, at least on paper, Colin.

Alex

_________________
"Indecision is the key to flexibility" .... Bumper sticker


Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 11:50 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Fri Dec 17, 2010 6:22 pm
Posts: 1295
First name: Miguel
Last Name: Bernardo
Country: portugal
Focus: Build
Status: Semi-pro
African Blackwood is imo the perfect fingerboard wood. Except that it's expensive and hard on tool edges.

I guess most ebony blanks that end up as fingerboard are far from quartered and folks use it all the same. In my last guitar I had a better quartered piece of ebony (easier to see because it was not jet black, more of a grey black) and the pores were larger than usual. I wonder if QSawn ebony shows the pores more effectively?

Great find!

_________________
member of the guild of professional dilettantes


Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 12:19 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Thu Feb 09, 2006 2:35 pm
Posts: 2951
Location: United States
First name: Joe
Last Name: Beaver
City: Lake Forest
State: California
Focus: Build
I'm uncertain of the meaning of shrinkage data. As I understand it, it is done by measuring a block of green wood, then drying it and re-measuring.

What I don't know is are the stated shrinkage values indicative to what happens when a dry piece of wood is moved from a 40% RH to say, a 60% RH?

_________________
Joe Beaver
Maker of Sawdust


Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 12:28 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Wed Apr 08, 2009 9:34 am
Posts: 3081
I've never liked ABW for fingerboards as it is terribly stringy when routing for inlays, but loved using it for bridges. Rings like a bell when dropped on a saw table. Ebony goes "thud".


Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 1:24 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Fri Jan 22, 2010 9:59 pm
Posts: 3598
First name: Dennis
Last Name: Kincheloe
City: Kansas City
State: MO
Country: USA
Focus: Build
Status: Amateur
Joe Beaver wrote:
I'm uncertain of the meaning of shrinkage data. As I understand it, it is done by measuring a block of green wood, then drying it and re-measuring.

What I don't know is are the stated shrinkage values indicative to what happens when a dry piece of wood is moved from a 40% RH to say, a 60% RH?

IME, the expansion rates do remain similar after drying. Ebony will always move much more than mahogany when the humidity changes. That's why fret ends poking out and cracks along the edges of the fingerboard extension are common with ebony... and why the popsicle brace was invented, to try and stop them.

But since African ebony's quartersawn rate is so high already, and flatsawn isn't that much worse, it's probably ok to use it flatsawn. You're going to have to put up with the problems it causes either way.

Some builders glue the fingerboard with epoxy rather than typical water-based glue. On a large area joint like that, the wood will absorb water from the glue and swell up, then stick in place, and then shrink after the glue dries. And since the ebony swells and shrinks more than the stuff it's being glued to, you get built-in stress. Cupping is also a problem with water-based glues, unless you spread water on the outer face to counteract it. But then you get even more expansion, and more built-in stress.


Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 4:07 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Fri Jul 10, 2009 4:44 am
Posts: 5505
First name: colin
Last Name: north
Country: Scotland.
Focus: Build
Status: Semi-pro
What they said...
And I like it for FB's and bridges, can't afford B & S!

_________________
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.


Top
 Profile  
 
PostPosted: Tue Sep 12, 2017 5:36 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Tue Mar 01, 2011 1:32 pm
Posts: 3470
First name: Alex
Last Name: Kleon
City: Whitby
State: Ontario
Zip/Postal Code: L1N8X2
Country: Canada
Focus: Build
Status: Amateur
Turning squares can be a cheaper source for ABW bridges. I bought three at 1 1/2" square by 9" long that were 2nds for 50 cents/inch. Only one had a crack in one end, so 9 FB's for $13.50. I'll be getting more on Saturday.

Alex

_________________
"Indecision is the key to flexibility" .... Bumper sticker


Top
 Profile  
 
PostPosted: Wed Sep 13, 2017 3:05 pm 
Offline
Mahogany
Mahogany

Joined: Tue Jan 26, 2016 10:59 pm
Posts: 54
First name: Jonny
Last Name: Fifield
Country: Canada
Focus: Build
Status: Amateur
Colin North wrote:
What they said...
And I like it for FB's and bridges, can't afford B & S!


I can't afford back and sides either Colin lol

But I do love the smell of it when I worked a few bridges in the past

_________________
"Practice enough till the results aren't hopes but expectations" forum member Peter Havriluk


Top
 Profile  
 
PostPosted: Thu Sep 14, 2017 10:53 am 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Thu Feb 12, 2009 12:12 pm
Posts: 3293
First name: Bryan
Last Name: Bear
City: St. Louis
State: Mo
Country: USA
Focus: Build
Status: Amateur
the shrinkage percents may be very similar between mahogany and ABW but I would expect ABW to gain and lose mosisture much, much more slowly than hog. I wouldn't count on them moving "together."

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 14 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: Bing [Bot], Melt in the Sun and 22 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
phpBB customization services by 2by2host.com