Share:
Notifications
Clear all

Back bow on a neck carve

8 Posts
6 Users
34 Reactions
307 Views
USADave
(@usadave)
Estimable Member Customer
Semi Professional
Rep Points: 269
Joined: 3 years ago
Posts: 32
Topic starter  

Hi Everyone,

I just finished carving (I should say my CNC just finished carving... lol) a neck blank (from what WAS a dead flat piece of maple) and the neck has developed a back bow. (while not entirely unexpected this is a little more than what I am used to at this stage of the game)  The truss rod that will be installed is a double action one; however, I am wondering if I should continue or just scrap it and try again with a more agreeable piece of wood? If I place a straight edge on the fretboard side the back bow is approximately 1/16 at the heel and headstock.

 

IMG 0469

 

 

Any insight would be greatly appreciated!

 

-Dave


   
Boo, Russ and Robin reacted
Quote
tv1
 tv1
(@tv101)
Illustrious Member Customer Registered
Luthier
Rep Points: 28066
Joined: 4 years ago
Posts: 3037
 

I'd be a little worried in that the neck has immediately shown such definite bow tendencies - suggests that it's not a very stable piece of wood, and that you might be forever tweaking the truss rod to keep it straight (ie it'd be prone to minor changes in heat/humidity or string gauge changes, etc).

Maybe leave it a day or three and see where it stabilises?

 

Online guitar making courses – guitarmaking.co.uk


   
Boo, Russ, Robin and 1 people reacted
ReplyQuote
swepri
(@swepri)
Honorable Member Customer
Luthier
Rep Points: 2556
Joined: 2 years ago
Posts: 216
 

Newbie answer here.

I would leave it for a couple of days to see where it settles. If it gets worse, then the decision would be easy.

The string pressure will pull it a tiny bit straighter and maybe the fretboard could help, if glued on straight. But I don't know what the experienced builders here would do. I guess we will know soon.


   
Boo, tv1, Russ and 1 people reacted
ReplyQuote
USADave
(@usadave)
Estimable Member Customer
Semi Professional
Rep Points: 269
Joined: 3 years ago
Posts: 32
Topic starter  

@tv101 Yup... I agree... Not a big deal to scrap it. But definitely am curious to see what the overall consensus is. 🙂


   
Robin, Boo, tv1 and 1 people reacted
ReplyQuote
USADave
(@usadave)
Estimable Member Customer
Semi Professional
Rep Points: 269
Joined: 3 years ago
Posts: 32
Topic starter  

@swepri Agreed...


   
swepri, Robin, Boo and 2 people reacted
ReplyQuote
Russ
 Russ
(@russ)
Illustrious Member Customer
Luthier
Rep Points: 28768
Joined: 4 years ago
Posts: 2485
 

@usadave

Hi Dave, was the neck blank quarter sawn or slab cut? I agree that leaving it for a few days to see if it settles. If it doesn't move from the position that it is in then try supporting it in a neck caul and plane the hump out by hand. 🤷🏻‍♂️

🙏🎸🙂🎶

 

🗝️ "Life's what you make it"🗝️


   
USADave, swepri, Robin and 2 people reacted
ReplyQuote
Boo
 Boo
(@boo)
Illustrious Member
Luthier
Rep Points: 34881
Joined: 6 years ago
Posts: 3835
 

@usadave You could spend ages messing about with it, using various methods but it’s not worth it for me. I would just start again with a new blank. 
Don’t throw this one out or burn it, you can use it for a myriad of things like making marker dots or repair work bits for other necks etc. 

Make guitars, not war 🌍✌️🎸


   
USADave, Russ, swepri and 1 people reacted
ReplyQuote
NSJ
 NSJ
(@nsj)
Noble Member Customer
Luthier
Rep Points: 2408
Joined: 1 year ago
Posts: 497
 

Posted by: @usadave

Hi Everyone,

I just finished carving (I should say my CNC just finished carving... lol) a neck blank (from what WAS a dead flat piece of maple) and the neck has developed a back bow. (while not entirely unexpected this is a little more than what I am used to at this stage of the game)  The truss rod that will be installed is a double action one; however, I am wondering if I should continue or just scrap it and try again with a more agreeable piece of wood? If I place a straight edge on the fretboard side the back bow is approximately 1/16 at the heel and headstock.

 

-- attachment is not available --

 

 

Any insight would be greatly appreciated!

 

-Dave

 

My first neck developed back bow after carving, single action rod too! Anyway, week or two later when it came to fret levelling etc it had sorted itself.

 

Stewmac actually makes a jig for the issue, I think it's pretty common but you can use the jig to hold it level for doing the frets. But with a dual action rod you can just straighten it out anyway.

 

I'd use it myself, wouldn't worry at all. Worst case I'd make another neck later if it became a problem.

 


   
USADave, Russ, Boo and 2 people reacted
ReplyQuote
Share: