create an angle in existing neck pocket

has anyone ever angled an existing neck pocket? I have a scenario that would require extreme shimming to get the bridge/action acceptable. Or does anyone have a good method to create a tapered/angled shim?

I've put cardboard shims under the neck until I get the desired angle, measure the thickness of the amount of shims required and then using a sanding block, sand the bottom of the neck heel to match the amount of wood to achieve the angle. This of course assumes you have enough wood in the heel to remove some.

so you take the mesurement of your shims and thin the headstock end of the neck pocket by that amount. then of course trying to make it taper so that the neck fits against the pocket. sounds like it is tricky.
or are you talking about sanding the neck heel and not the pocket?

If you have a router you can use a laminate trimmer bit (bottom bearing) to make a neck template from your neck pocket.

Then it's a matter of propping the template on the neck angle you need with small wooden chocks, and running your top bearing bit around it.

If you have a router you can use a laminate trimmer bit (bottom bearing) to make a neck template from your neck pocket.

Then it's a matter of propping the template on the neck angle you need with small wooden chocks, and running your top bearing bit around it.

A+ and I've done it.

well since I actually made a template from the neck to widen that neck slot I should be able to use that one right? So essentially I would shim that template to the neck angle and then route. It might be tricky to get the proper shimming. Les pauls use a 4 1/2 degree angle and I think that would be too much. Perhaps I could determine how big of a shim it would take to get the neck at the proper angle and then use that

Try this:

1.) Put the neck in the pocket and the bridge on.

2.) Angle the neck to say, 3 degrees.

3.) Lay a straight edge on the frets and adjust the saddles until the straight edges touches alsong the D or G string path.

4.) Measure the amount the heel of the neck has been raised by. Your saddles will need to be able to be dropped by this amount and not run out of adjustment (but be close to their lowest).

5.) If you can't do this then increase the angle by 1 degree and go back to step 3. If you have too much room left to still lower the saddles then decrease the angle.

This method calculates the offset caused by your removal of the front of the neck pocket and factors this in to being able to lower your saddles to a zero-relief point at their lowest, leaving you with ample adjustment upwards.

It's also a good idea to draw up a full-sized diagram to get your head around it.

well this is a floyd bridge. I just have it wedged in right now. I haven't drilled the stud holes yet because I still have the option of recess routing. (the owner would prefer I didn't) How do I determine 3 degrees?

This method calculates the offset caused by your removal of the front of the neck pocket and factors this in to being able to lower your saddles to a zero-relief point at their lowest, leaving you with ample adjustment upwards.

when you say the front of the neck pocket I assume you are talking about the peghead side.

when you say the front of the neck pocket I assume you are talking about the peghead side.

Yes.

3 degrees? Remember trigonometry? Or you can buy an angle finder - or a protractor. But with this method you can just guess where it looks correct and adjust more angle or less angle until it's correct. You don't need a specific angle - that's a handy part about it.

Remember to factor in pickup rout depth and ring height to your eventual neck angle and neck pocket depth. While a recessed bridge is one solution, it can leave no room for pickup rings.

I never took trig but I know what 3 degrees is. I just thought it would be tough to put a protractor in a spot where you could measure it. but I get what you are saying about just using a straightedge and experimenting how much to angle. Kind of like a n acoustic neck reset where they put a straight edge to the bridge to figure the angle. (not that I have done that) thanks a lot. I will have to decide if I want to recess or try this. It sounds like an interesting experiment. do you use any special router bit?

I find if I convert it into a gradient it is much easier to translate on to the guitar.

The formula I use is sin(angle)*length = height.

Therefore, for example, 3 deg equates to a rise of 5.23mm over 100mm distance.

When I was doing this for my LP Jnr-esque build I wrote it up at http://damacleod.wordpress.com/2011/02/05/calculating-the-guitars-neck-angle/

I find if I convert it into a gradient it is much easier to translate on to the guitar.

The formula I use is sin(angle)*length = height.

Therefore, for example, 3 deg equates to a rise of 5.23mm over 100mm distance.

When I was doing this for my LP Jnr-esque build I wrote it up at http://damacleod.wordpress.com/2011/02/05/calculating-the-guitars-neck-angle/

You guys are so much smarter than me! That is why I'm here.
I looked at your link. Very cool. Now I am going to be just shimming/angling the neck to find the angle probably using the method suggest above. But I am going to try and save that formula.
I wonder if I could apply that and use just the length of the neck pocket

but once I decide on the angle i can use a straight router bit? i would think so. I am trying to visualize how I am going to do this. Ideally I want the raise to be at exactly the same place as it is when shimmed. so I when I do put on the template and route I should try and align the shims I use to raise the template with bridge end of the neck pocket. right? I hope that made sense

I wonder if I could apply that and use just the length of the neck pocket
You could, but when you're working with small distances, the margin of error is multiplied.
but once I decide on the angle i can use a straight router bit? i would think so. I am trying to visualize how I am going to do this. Ideally I want the raise to be at exactly the same place as it is when shimmed. so I when I do put on the template and route I should try and align the shims I use to raise the template with bridge end of the neck pocket. right? I hope that made sense
What I did when I was routing the angled neck pocket, was to build a box that sat around the guitar body. I hinged this at the front and then shimmed up the back the height I needed. That way you can measure a longer distance (the length of the box) and calculate the shim height you need. So for example if the box is 200mm long, for a 3 deg angle you need to shim the tail end up by approx 10.5mm. The router then rides on the top edge of the box meaning that the straight cutter is running at the correct angle.

I've only got one picture of when I was doing this (below) and it isn't particularly clear. You can see the maple top of the body sitting in the box, and the box itself, but it doesn't show the shims on the left hand side.

http://damacleod.files.wordpress.com/2011/02/chamfer1.jpg

BTW: This picture above shows when I was chamfering the front face of the body. This picture below shows the pocket being cut and the template is sitting on top of the same box frame. I was using a 3/8" top bearing straight cutter to follow the template.

Hope this helps.

http://damacleod.files.wordpress.com/2011/02/routing02.jpg

Incredible.

Two nickels on the ass end of the neck routing template do a nice job.

Two nickels on the ass end of the neck routing template do a nice job.

good idea

i was just figuring this out today myself. To figure out how much to raise the template for a given angle, the formula is

tan angle A = opposite side / adjacent side

A = the angle of the neck pocket
adjacent side = length of our template (16" for a tele)
Opposite side = how much to raise the back of the template

so for 1 degree tan 1deg = opp / 16" or 16*tan 1 = opp or .28"

Wow! and I thought the math teacher was full of it when she said this would be useful some day. :mrgreen:

EDIT: The math is correct but that seems more than a tad high... hmm....

i was just figuring this out today myself. To figure out how much to raise the template for a given angle, the formula is

tan angle A = opposite side / adjacent side

A = the angle of the neck pocket
adjacent side = length of our template (16" for a tele)
Opposite side = how much to raise the back of the template

so for 1 degree tan 1deg = opp / 16" or 16*tan 1 = opp or .28"

Wow! and I thought the math teacher was full of it when she said this would be useful some day. :mrgreen:

EDIT: The math is correct but that seems more than a tad high... hmm....

so is the length of your template measured from end to end? or just the measurement of the actual routing cutout?

yeah over a quarter inch for 1 degree seems way too much.

yeah over a quarter inch for 1 degree seems way too much.

Sounds 'bout right. Remember you've got to take into acount the height of the fretboard above the body no matter how you do it.

If you had a really, really shallow neck pocket you wouldn't need any neck angle.

well since I actually made a template from the neck to widen that neck slot I should be able to use that one right? So essentially I would shim that template to the neck angle and then route. It might be tricky to get the proper shimming. Les pauls use a 4 1/2 degree angle and I think that would be too much. Perhaps I could determine how big of a shim it would take to get the neck at the proper angle and then use that

Here is a Les Paul section

78081

The angle that matters is the angle of the neck WRT the plane that the bridge is on. The 4.4 deg is the total angle caused by the carve ' hill ' plus the angle required by the Tune o Matic bridge.
Result you need about a 2 deg angle.
Another way of looking at it is that the TOM type bridge height is 17mm at the saddle whereas the tele types are 11 mm give or take. Therefore you need to create an angle such that the strings ' lift ' by 6 mm or 1/4"

I got ya. but wouldn't the method that Nick JD described arrive at the same thing?

Indeed he does , I was just clearing up the geometry confusion.
From a woodworking standpoint Colt pretty much has it down , You are probably looking for 1.5 mm relief at the headstock end of the pocket.
If you were to use a ski run routing jig you can dummy run the cut like this ----

with the neck on adjust the router till the cutter is touching the 21 fret , then move the router till it is where the bridge is and adjust the slope till the router tip is at the desired height. Go back and check the 21 fret , it will be off depending on where the pivot point is but keep at it until the cutter is shaking hands with the two points that matter ie the last fret and the saddle.
Once you have that you have the correct angle for the pocket although of course you have to lower the cutter.

pics will give you the idea. The little blocks just slide back and forth to adjust the angle

78118

78119

it is looking more and more complicated. I do get the idea that we are talking about the angle from the bridge etc but I still think that I can acheive the desired result by shimming the neck pocket template at the proper point where the neck shims would be. Can't I?

it is looking more and more complicated. I do get the idea that we are talking about the angle from the bridge etc but I still think that I can acheive the desired result by shimming the neck pocket template at the proper point where the neck shims would be. Can't I?

Yes this works. Only one question , how do you determine the correct angle / shims ?

Thing to do in this case is do it in increments , don't take too much out at one go. Try a shallow angle (thin shim ) remount the neck and have a look where you are with it , if it needs more the shim a little higher etc. Your bridge will have some adjustment anyway.

Only one question , how do you determine the correct angle / shims ?


In my first post (#7) I forgot to say that the height you have to raise the heel end of the bridge by to get the correct angle, is the same amount you need to raise the neck pocket template by - at the bridge side of the neck pocket.

well i hope to get to it tomorrow or friday. got do brakes in the car first. I will give a full report.

http://en.wikipedia.org/wiki/File:Star_guitar_body.gif

this is the shape of the body. I know that is irrelevant as far angle goes, but imagine what a pain it would be to build a box around this! I am leaning towards just recessing the bridge.
but you guys have really clarified this for me. I hadn't thought it thru. now I see why it is way better to work on a longer angle. I thought that i could just prop it up (the template) at the neck pocket and route. but it finally dawned on me that both ends of the template need to rest on something. duh! man I learn a lot on this forum

http://en.wikipedia.org/wiki/File:Star_guitar_body.gif

this is the shape of the body. I know that is irrelevant as far angle goes, but imagine what a pain it would be to build a box around this! I am leaning towards just recessing the bridge.
but you guys have really clarified this for me. I hadn't thought it thru. now I see why it is way better to work on a longer angle. I thought that i could just prop it up (the template) at the neck pocket and route. but it finally dawned on me that both ends of the template need to rest on something. duh! man I learn a lot on this forum

Probably better if you don't do it, if you are not confident with this.

BTW. You can just prop the neck pocket template up - it's really that simple.

ok I still haven't routed. yesterday I actually put the studs in just to see how it actually would be. (remember before I just had the floyd wedged in without studs) my recess template assumes that a floyd is installed. (you trace the out line of of the floyd on the guitar and the line the template up with that. you then remove the stud inserts and route. and of course put them back in)
Ok. My neck template is about 10-12" long. I prop the end of that up at the same spot where a neck shim would go right? (obviously a neck shim would go in the pocket but the template shims should line up with where a neck pocket shim would go. on the body next to the neck pocket. right?) Ok then where does the other end of the template rest? rig up some blocks or something so it sits flat on the body and then shim the proper end? Looking at these drawings of boxes and frames kind of scared me. Not that I don't get it but it makes me wonder if i will be accurate enough. Either way I have learned a hell of a lot in this thread. If i don't do it on this one I definitely will on one in the future.

Oh. when I had the floyd wedged in there with strings the action was too high even with 3 business cards width of shims. a floyd needs to be off the body a little just to allow a dive bomb with it. (the edge of the bridge pivots forward and needs to clear the body) any I'm rambling. but when i put a straightedge on it seemed to hit right where the g-d strings came off the post. that is also a reason that I put the studs in. but again after all that the action was still too high. (with the studs in and the floyd down as low as possible)

I put the studs back in and started experimenting with neck shims. I started out with 1/8". that was way too much. I then went to 3/32. still too much. I settled on 5 business cards. and that is a good angle. so after all is said and done I think I am going to leave this particular guitar like that if the owner likes it. but I am still going to try angling the neck pocket on one of my own beaters. Thanks for all the awesome help.

Upon further examination I am again leaning heavily towards angling it again. I just did another post about angle measuring devices. The shims are causing the tongue of the neck to rise a bit. Plus he wants at least another shim in it (business card)