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VIEW FULL LIVE VERSION : Angled neck bolts?
ctmullins 05-20-2008, 08:13 AM Hi guys/gals,
I'm in the process of crafting a body to mate with a Carvin four-string fretless neck. The neck heel is not pre-drilled, so I have the flexibility of neck bolt placement.
I've been wondering about drilling the neck bolt holes at an angle, rather than straight into the neck. The idea is to have the heads of the bolts at more or less the "standard" positions, but have the tips nearer each other, forming something of a "V" pattern. My thinking is that this could create a more stable neck joint.
I'm sure I'm not the only one to have thought of this. Anybody have any opinions on this, one way or the other?
Thanks!
pilotjones 05-20-2008, 11:28 AM The bolts entering at angles to each other will set up the wood of the neck between the bolts in tension. (Imagine it--the bolts are pulling the center area of wood in somewhat opposite directions.) Whether this would be enough to cause failure (a crack which would relieve the tension) remains to be seen.
vinny 05-20-2008, 12:27 PM I don't have anything to offer on the neck joint, but I'll tell you this: Producing angles in two assembled parts that don't otherwise need them increases the likelihood of error & narrows the tolerances for fit. I've been doing machine design for many years & one of the things I've learned along the way is to never over-engineer something simple that works. YMMV
()smoke() 05-20-2008, 01:03 PM the angles won't produce a more stable joint...just drill perpendicular to the parts
Lalabadie 05-20-2008, 01:06 PM Don't solve what's working ;)
eleonn 05-20-2008, 02:46 PM Like my ex boss used to say: if it works and works well... don't f*ck*ng touch it!!! :smug:
You're just adding an insignificant tension force between the screws. I don't think the neck shifting in the pocket is a common problem, and you're adding some other complications (getting the screw heads to sit flat, etc)
waseok 05-20-2008, 03:21 PM Man i have 4 bolts on my maple neck bass, and i tell u that thing does not move! and yeah they are str8! so wth?
Human Bass 05-20-2008, 03:30 PM I remember seeing a guitar luthier that had a very cool neck joint that he called wedge joint. I will try to find it...
Human Bass 05-20-2008, 03:33 PM HERE IT IS!
http://www.andersonguitars.com/wedgie.html
hooray for me!
()smoke() 05-20-2008, 04:38 PM HERE IT IS!
http://www.andersonguitars.com/wedgie.html
hooray for me!
that's interesting!
Yep, unless you do chinups on your bass it's probably a bit overkill.
Nelson Guitars 05-20-2008, 06:58 PM The V shape won't help. Imagine putting a 1/4" shim in between the neck and the pocket. Drill your pilot holes and insert the screws. Everything is tight. Now remove the shim and tighten the screws harder. Hmmmm. Since the screws are in a V to each other you have tighter screws but you still have a 1/4" space! Well, excepting flex and tolerance of the various pieces but you get the point.
There isn't a great deal of upward pressure on this joint anyway. Most neck screw failures happen because the screws are removed and replaced a bunch or the neck was stressed by something other than the strings.
Greg N
The V shape won't help. Imagine putting a 1/4" shim in between the neck and the pocket. Drill your pilot holes and insert the screws. Everything is tight. Now remove the shim and tighten the screws harder. Hmmmm. Since the screws are in a V to each other you have tighter screws but you still have a 1/4" space! Well, excepting flex and tolerance of the various pieces but you get the point.
There isn't a great deal of upward pressure on this joint anyway. Most neck screw failures happen because the screws are removed and replaced a bunch or the neck was stressed by something other than the strings.
Greg N
A very good point. so, he would actually be making things worse.
I think he was primarily thinking about the neck being able to slide around, as opposed to being tight in the pocket. The answer to that, of course, is to just drill the holes very precisely, and no bigger than they need to be to clear the threads.
-Nick
WarriorJoe7 05-20-2008, 07:10 PM I think Ned Steinberger had a patented design on slanted neck bolts. I can't think of the instrument but it wasn't under his name. This was probably 4-5 years ago and that particular instruement never took off
I think Ned Steinberger had a patented design on slanted neck bolts. I can't think of the instrument but it wasn't under his name. This was probably 4-5 years ago and that particular instruement never took off
Yeah, but were they slanted in a V, or just slanted to pull it tight into the bottom of the pocket, and towards the body at the same time?
ctmullins 05-20-2008, 09:14 PM Wow, thanks for all of your responses! I figured that angling the bolts would probably be more trouble than it's worth, but I have an opportunity to maximize the neck/body joint, and I want to do the best job I can. Do threaded inserts make a noticeable sonic difference?
Nelson Guitars 05-20-2008, 09:26 PM The neck really needs to fit snugly in the pocket and not depend on the bolts to keep it from moving. Tight machining is always preferred but I will take over sized bolt holes and a tight neck to pocket joint any day over the opposite.
Most of the string tension is pulling the neck into the pocket. If it weren't for action height and player handling then a snug fit may be enough to hold a neck in place alone. I see many necks in my repair work that look like people thought they were torquing down the head on an old Ford flat top V8. It just doesn't take that much force to hold these things in place.
Greg N
PS. Saw your question after I posted. Threaded inserts won't make any real difference in tone. They will however allow you to remove and reinstall the neck as much as you like without stripping the threads. Just don't pull out the torque wrench because you have them.
The neck really needs to fit snugly in the pocket and not depend on the bolts to keep it from moving. Tight machining is always preferred but I will take over sized bolt holes and a tight neck to pocket joint any day over the opposite.
Most of the string tension is pulling the neck into the pocket. If it weren't for action height and player handling then a snug fit may be enough to hold a neck in place alone. I see many necks in my repair work that look like people thought they were torquing down the head on an old Ford flat top V8. It just doesn't take that much force to hold these things in place.
Greg N
PS. Saw your question after I posted. Threaded inserts won't make any real difference in tone. They will however allow you to remove and reinstall the neck as much as you like without stripping the threads. Just don't pull out the torque wrench because you have them.
Have you compared a loose pocket and a tight pocket sound-wise? I don't have any frame of reference, since the one bass I've built and the other basses I've bought/tinkered with all fit fairly loose. I certainly don't have any complaints about the sound though.
Threaded inserts will actually get the neck quite a bit tighter without you even knowing it. The fine thread pitch, and the reduced stiction will pull it in much tighter with a lot less force on your screwdriver.
If you don't use the inserts, one tip I picked up somewhere (maybe here?) is to rub some wax on the threads of your screws, They'll go in smoother, and you'll have a much easier time telling when they're tight, as opposed to just sticking.
As far as removing the neck repeatedly goes, there's another trick that I picked up working on plastic stuff as a kid(strips much easier than wood). All you do is turn the screwdriver backwards until you feel a little clunk as the thread drops into the thread from the previous assembly. Then turn it in normally. This way you're not cutting new threads across the old ones. Assuming you're not overtightening the screws, You'll never strip the threads out in anywhere near the number of times you'll likely disassemble a bass.
3/4 of the people reading this are probably thinking "Duh, everyone knows that", but I'm always surprised how many people don't. With the number of stripped screw threads I've seen in my short time on this forum, I figure it's worth pointing out anyways. :D
WarriorJoe7 05-21-2008, 03:13 AM Yeah I always screw backwards until the screw drops but I don't think this is common knowledge. i know it wasn't for me until after I had a really hard time getting a neck screw back in once. Luckily it was a cheap washburn years ago.
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