Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Sat Nov 30, 2024 10:19 pm


All times are UTC - 5 hours





Post new topic Reply to topic  [ 13 posts ] 
Author Message
 Post subject:
PostPosted: Sun Jul 08, 2007 10:03 am 
Offline
Site Admin
User avatar

Joined: Mon Dec 27, 2004 5:02 am
Posts: 8551
Location: United States
First name: Lance
Last Name: Kragenbrink
City: Vandercook Lake
State: Michigan
Zip/Postal Code: 49203
Country: USA
Focus: Build
Status: Semi-pro
I am having a heck of a time trying to sand some flamed Koa sides. I have sent them through my sander, slow, fast, at an angle, stright in, super light passes, heaver passes, 80 grit and 100 grit, and every time, the "flames" in the Koa appear to darken. I had the same trouble with the back set too, but I was able to run the back through the sander at a 90* angle to the flame, and that fix the problem. The sides are too long to do that.

Any ideas?

Thanks

_________________
Support the OLF! Bookmark our STEWMAC link Today!
Lance@LuthiersForum.com


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 10:29 am 
Offline
Koa
Koa

Joined: Fri Jun 30, 2006 4:23 pm
Posts: 1694
Location: United States
First name: Lillian
Last Name: Fuller-Watson
State: WA
Country: USA
Focus: Build
Status: Amateur
Scraper?

_________________
Aoibeann


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 10:47 am 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Thu Oct 06, 2005 1:05 pm
Posts: 3350
Location: Bakersville, NC
Focus: Build
Status: Professional
Lance, when I do koa the sanding process does seem to make the curl a bit darker and more pronounced, its normal..... don't worry about it. Did you see my koa guitar? thats how it went.

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 11:14 am 
Offline
Site Admin
User avatar

Joined: Mon Dec 27, 2004 5:02 am
Posts: 8551
Location: United States
First name: Lance
Last Name: Kragenbrink
City: Vandercook Lake
State: Michigan
Zip/Postal Code: 49203
Country: USA
Focus: Build
Status: Semi-pro
Hesh, here is how it looks.





Here is how the back came out.



Peter, I dont recall seeing this on your guitar?

_________________
Support the OLF! Bookmark our STEWMAC link Today!
Lance@LuthiersForum.com


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 11:17 am 
Offline
Cocobolo
Cocobolo

Joined: Fri Jun 15, 2007 12:14 am
Posts: 332
Location: United States
Fresh abrasive will help.
Sharp abrasives generate a lot less heat.

Mark






Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 11:19 am 
Offline
Site Admin
User avatar

Joined: Mon Dec 27, 2004 5:02 am
Posts: 8551
Location: United States
First name: Lance
Last Name: Kragenbrink
City: Vandercook Lake
State: Michigan
Zip/Postal Code: 49203
Country: USA
Focus: Build
Status: Semi-pro
Thanks Mark, I tried 80 and 100 grits, both brand new.

_________________
Support the OLF! Bookmark our STEWMAC link Today!
Lance@LuthiersForum.com


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 11:22 am 
Offline
Koa
Koa

Joined: Thu Dec 01, 2005 9:40 am
Posts: 600
Location: United States
Lance, your sides look normal to me. The back is cut from a very different tighter fiddle back figure and your "dark" bands are there, but much narrower and deeper. The side grain undulations (what makes curl) are much broader and reflect back wider of course. Looks like you have some other broken curly figure going on also which might be causing the splotchy look, but it is "figure". Doesn't look like any of the wood is "scorched" at all.


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 11:27 am 
Offline
Site Admin
User avatar

Joined: Mon Dec 27, 2004 5:02 am
Posts: 8551
Location: United States
First name: Lance
Last Name: Kragenbrink
City: Vandercook Lake
State: Michigan
Zip/Postal Code: 49203
Country: USA
Focus: Build
Status: Semi-pro
Thanks Larry,

I will plow forward!

_________________
Support the OLF! Bookmark our STEWMAC link Today!
Lance@LuthiersForum.com


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 11:48 am 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Thu Oct 06, 2005 1:05 pm
Posts: 3350
Location: Bakersville, NC
Focus: Build
Status: Professional
[QUOTE=LanceK]

Peter, I dont recall seeing this on your guitar?[/QUOTE]

It looks different after the finish is applied!   

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com


Top
 Profile  
 
 Post subject:
PostPosted: Sun Jul 08, 2007 12:19 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Sat Jan 08, 2005 3:37 am
Posts: 2670
Location: United States
First name: John
Last Name: Mayes
City: Norman
State: OK
Focus: Build
Status: Professional
Everytime flame starts to darken/scorch it's always past due for some new
abrasives.... Hard to say for sure that's what's happening here though fresh
sandpaper wouldn't hurt, and light passes will build up much less heat.

_________________
John Mayes
http://www.mayesluthier.com


Top
 Profile  
 
 Post subject:
PostPosted: Mon Jul 09, 2007 2:48 am 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Mon Jan 03, 2005 7:40 am
Posts: 2694
Location: United States
First name: John
Last Name: How
City: Auburn
State: Ca
Country: USA
See if it cleans up with a random orbital. I always sand to a scratch free texture right after I thickness backs, sides and tops and before I do any further processing. It saves much time and produces a much nicer finish after everything is put together. Then the pre-finish sanding is so much easier.

_________________
Tickle your guitar daily, and it'll tickle you back.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 13 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 30 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