Official Luthiers Forum!

Solely owned and operated by Lance Kragenbrink
It is currently Fri Feb 21, 2020 12:06 am


All times are UTC - 5 hours





Post new topic Reply to topic  [ 4 posts ] 
Author Message
 Post subject: Advice on a Martin Neck
PostPosted: Sat Jul 14, 2018 6:56 pm 
Offline
Koa
Koa

Joined: Wed Feb 17, 2016 8:54 am
Posts: 591
State: Texas
Country: United States
Focus: Repair
I have a 69 D35 in the shop. Initial cause of concern was that there was a crack in the neck about 1 1/2" from the heel. Owner informed me that the crack had been glued about 4 previous times and had continually come undone.

My course of action was to remove the whole neck, seprate the two pieces, scrape out whatever contamination is present, reglue with hide glue, reinstall the neck, call it done.

The top portion of the neck came out just fine. However the heel portion simply will not budge. I have the stew mac neck removal jig and it it simply not moving with the steam injection method.

Feeling around the heel it looks like some previous home gamer decided to glue the outer edge of the heel the sides of the body. I ran a pallet knife around the edge to sever the hold it had on the neck. I also took a thin feeler gauge to create some clearance between the sides of the neck block and the dovetail. Still not budging.

Plan F at this point is to reglue the neck to the heel portion after removing the crud from previous glue attempts, waxing the exposed portions of the dovetail block so I don't glue it back to the dovetail. then use the extra torque from the neck and try steam again but deeper in the joint.

What I think has happened is that the lower portion of the dovetail was fit WAY too friggin tight with no space for movement as the wood contracted over time. The upper portion was not fit so well so it moved all over the place while the lower part stayed fit. This is just my thought as I could be wrong but there is definitely something amiss with the upper and lower portion of the dovetail.

My question is, has anyone run into a problem like this before, and how did you resolve it?


Top
 Profile  
 
PostPosted: Sun Jul 15, 2018 5:18 am 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Mon Dec 27, 2010 9:06 pm
Posts: 2695
Location: Magnolia DE
First name: Brian
Last Name: Howard
City: Magnolia
State: Delaware
Zip/Postal Code: 19962
Country: United States
Focus: Repair
Status: Professional
My approach would likely be to use a drill and waste out the center of the tennon on the broken heel so it can be steamed and worked out. A injection hole in each side right down the joint line for a steam needle will help. you can work the edges of the joint inward and free the piece then just replace the section in the center you wasted out after you glue the heel back on the neck and you're almost home.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/



These users thanked the author B. Howard for the post: DanKirkland (Sun Jul 15, 2018 2:18 pm)
Top
 Profile  
 
PostPosted: Sun Jul 15, 2018 2:46 pm 
Offline
Koa
Koa

Joined: Wed Feb 17, 2016 8:54 am
Posts: 591
State: Texas
Country: United States
Focus: Repair
B. Howard wrote:
My approach would likely be to use a drill and waste out the center of the tennon on the broken heel so it can be steamed and worked out. A injection hole in each side right down the joint line for a steam needle will help. you can work the edges of the joint inward and free the piece then just replace the section in the center you wasted out after you glue the heel back on the neck and you're almost home.


Thanks for that Brian. Just a follow up thought but in replacing the drilled out portion is it wise to maybe add a few tiny dowels so the replacement mahogany doesn't come unglued when the neck needs resetting again?


Top
 Profile  
 
PostPosted: Mon Jul 16, 2018 5:27 am 
Offline
Brazilian Rosewood
Brazilian Rosewood
User avatar

Joined: Mon Dec 27, 2010 9:06 pm
Posts: 2695
Location: Magnolia DE
First name: Brian
Last Name: Howard
City: Magnolia
State: Delaware
Zip/Postal Code: 19962
Country: United States
Focus: Repair
Status: Professional
i would not add any dowels myself. Don't want the graft to come loose on the next reset? Epoxy that part then.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/



These users thanked the author B. Howard for the post: DanKirkland (Mon Jul 16, 2018 9:20 am)
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 3 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