Author Topic: DARKENED Cocobolo top..Refinish?? (Read 220 times)

roberto · « **on:** June 19, 2011, 07:22:41 PM »

Hi!
My 1991 Alembic with Cocobolo top have definitely became almost black visually..Will sanding and refinishing wipe out the darkened wood and reveal the fresh Cocobolo colour again?
Anybody ever done this with success?
thanks.

regards
robert

terryc · « **Reply #1 on:** June 20, 2011, 01:44:07 AM »

What about a pic to see how dark it is?

chuck · « **Reply #2 on:** June 20, 2011, 07:20:00 AM »

If you sand you should use a good mask as the dust is toxic.

Chuck.

dfung60 · « **Reply #3 on:** June 20, 2011, 11:02:19 AM »

I think the darkness that the wood attains over time is part of the nature of that piece of wood. I guess you could strip the finish, resand the top, then refinish, but it would be a crapshot at best. It could easily cost thousands of bucks to try out.

David Fung

pierreyves · « **Reply #4 on:** June 20, 2011, 11:17:33 AM »

I think to get the original color, you have to sand at least 1 mm, what is not realistic. How long time the original color has turned black? the bass was exposed to the sun?

lbpesq · « **Reply #5 on:** June 20, 2011, 11:48:56 AM »

Also, cocobolo is very oily and may present problems when finishing. A review of the Factory-to-Customer threads will reveal that it isn't uncommon for Alembic to have problems with finishing cocobolo instruments. As I recall, Flax's Dire Wolf had to be refinished at least twice.

Bill, tgo

roberto · « **Reply #6 on:** June 20, 2011, 11:59:37 AM »

terryc, I ll post pictures..
dfung60, it wont cost more than $100 here.
pierreyves,I bought the bass in 1998 and as far as I remember, it is a little lighter that time..the wood figures/lines were visible.
chuck and lbpesq, thank you very much for the warning...makes me think twice..

regrads
robert

mica · « **Reply #7 on:** June 20, 2011, 01:00:35 PM »

It does darken over time, and the oxidization can penetrate a good mm or more. Just try to remove the same amount of wood on the top and the edge where it rounds over. I wouldn't worry about the peghead veneers, else you might sand through them.

The rate of oxidization is one of the reasons we don't like to slice up much Coco Bolo until we're really ready to use it. If we have an old bookmatch, the top will be darker than an elbow cut, which exposes deeper, less oxidized wood.

If you are adventuring into refinishing yourself, note that we use an acrylic urethane as a sealer, after wiping down with acetone to evacuate the oils from the surface. The bulk of the finish is polyester. Hope this helps!