Mile high action... actually, make that two miles

[HolmeBass]

> String tension at pitch is the same no matter what the action is like.

But the force trying to bend the neck increases as the action increases.

- John

The *torque* increases as the moment arm increases, due to the increased angle between the string and neck at the nut, but the force remains the same.

 

[Ewo]

yup, like darkstorm said you have the shim in the wrong place. slide it toward the bridge all the way. a 1/4 inch? the shim may be too thick. some people use pieces of buisness card.

Related to that:

If the shim is the full footprint of the neck pocket, all you've done is raise the plane of the neck relative to the plane of the body, by the thickness of the shim. Capisce? What you're trying to do is tilt the neck relative to the body.

So the shim should just be a narrow rectangle, positioned at the bridge side of the neck pocket (as staindbass said). Its long dimension is the full width of the neck pocket, but the short dimension is only about 3/8" or so.

As staindbass said, a business card will work, or a couple thicknesses with the same dimensions. And I've used a scrap of wood veneer, too.

Dan Erlewine's repair book has a good explanation of neck shimming.

 

[mongo2]

Related to that:

If the shim is the full footprint of the neck pocket, all you've done is raise the plane of the neck relative to the plane of the body, by the thickness of the shim. Capisce? What you're trying to do is tilt the neck relative to the body.

So the shim should just be a narrow rectangle, positioned at the bridge side of the neck pocket (as staindbass said). Its long dimension is the full width of the neck pocket, but the short dimension is only about 3/8" or so.

I much prefer a flat full pocket shim since all I want to doo is raise the plain of the neck closer to the strings and body and it doesn't mess with the body/neck geometry as much.

However, I have had some success using a "reverse" shim as described by the OP (or a combinatiion of flat and reverse shim) to allieviate the results of a ski jump/tongue flip. In the case of a combo shim, the reverse shim makes the ski jump more level with the body and the full pocket shim under the reverse shim raises the neck closer to the strings to provide lower action if desired.

 

[David Jayne]

The *torque* increases as the moment arm increases, due to the increased angle between the string and neck at the nut, but the force remains the same.

 

[allexcosta]

You're not really proving a point here.

You're right... It's just observation...

Have you seen a bass develop a bow and become useless just because someone switched from 040 to 045 strings? I have... Should that happen on a brand bass? No, but it still happens...

 

[SGD Lutherie]

Have you seen a bass develop a bow and become useless just because someone switched from 040 to 045 strings? I have... Should that happen on a brand bass? No, but it still happens...

Yep, I've seen it countless times. Happens because people put higher tension strings on and then never adjust the truss rod to compensate.

I'm not sure why someone would want very high action. I suppose if you play very simple parts it's OK, but you might not get the bass to intonate past a certain point.

 

[SGD Lutherie]

However, I have had some success using a "reverse" shim as described by the OP (or a combinatiion of flat and reverse shim) to allieviate the results of a ski jump/tongue flip. In the case of a combo shim, the reverse shim makes the ski jump more level with the body and the full pocket shim under the reverse shim raises the neck closer to the strings to provide lower action if desired.

All you need to do with a raised tongue is level out the frets up there. I'm doing that to a Warmoth Jazz right now. it had the usual hump up at the neck pocket area, and a raised tongue, so the last two frets are too high. The best thing to do is level out the fingerboard and out in some "fall away".

Adding some neck angle is usually a good thing though.

 

[MikeBass]

You're right... It's just observation...

Have you seen a bass develop a bow and become useless just because someone switched from 040 to 045 strings? I have... Should that happen on a brand bass? No, but it still happens...

Alex, I understand what you are saying, and no, I've never seen that happen- if it did I would be in massive suspect of the materials, not just a switch in string gauge.

A good friend of mine, Bob DeGeorge (plays with the Spinners and other Motown groups and I think he's on TB, but not often) has one of the, literally one of the very first 55-02's. He worked at Low Down Sound when the Skykine stuff first came out and Dan sent him one of the first..anyway, not only does he use heavy gauge strings (I think the Jamerson flats but with an added low B), his action is pretty damn high- to the point I don't think I would survive a set on that bass (I'll say this, I'm convinced it's US made- it's perfect in every way)
Bob is like 6'5 280- a stinkin' huge guy with hands like a Buick, so it works for him- and he travels the counrty with the Spinners as well.
With that same bass to this day.
And again, zero issues.

After 26 years of playing, the only basses I've had with neck issue of any sort were the Warwick I mentioned and my 70's Jazz- which are nortoriously know for crap necks due to sub-par materials used at times.

If a truss rod is working properly, then you can jack up the action and use heavy arse strings and it should be fine.
Hell, my 65 Hofner Club Bass with flats and high action sat for god knows how long in my Grandmothers garage before I got it.
It had a seriously bad bow in the neck, and the action is pretty high, but some adjusting and the neck is pretty flat with just a bit of relief.

 

[mongo2]

All you need to do with a raised tongue is level out the frets up there. I'm doing that to a Warmoth Jazz right now. it had the usual hump up at the neck pocket area, and a raised tongue, so the last two frets are too high. The best thing to do is level out the fingerboard and out in some "fall away".

Adding some neck angle is usually a good thing though.

Yeah I know, but these two were vintage basses and the owner didn't want the frets filed or the frets pulled and the fingerboard filed (my usual method). So I found another way and have since tried that first whenever that kind of repair comes my way. It's less work and less invasive.

 

[joeyl]

All you need to do with a raised tongue is level out the frets up there. I'm doing that to a Warmoth Jazz right now. it had the usual hump up at the neck pocket area, and a raised tongue, so the last two frets are too high. The best thing to do is level out the fingerboard and out in some "fall away".

Adding some neck angle is usually a good thing though.

I thought all Warmoth necks were indestructible! Is it a really old one, like when they offered vintage-construction necks?

 

[mongo2]

I thought all Warmoth necks were indestructible! Is it a really old one, like when they offered vintage-construction necks?

They ain't perfect, I've even found deadspots on them.

 

[joeyl]

They ain't perfect, I've even found deadspots.

I've found deadspots on them too, but I have yet to see a raised tongue on one.

 

[mongo2]

I've found deadspots on them too, but I have yet to see a raised tongue on one.

I had to cut the fingerboard extension off of one to fix it. But it was only one out of a couple of dozen I've used.

 

[SGD Lutherie]

I thought all Warmoth necks were indestructible! Is it a really old one, like when they offered vintage-construction necks?

They are pretty well made, but they do not level the frets when you get them. They do a fair job of pressing them in so they are pretty level, but they aren't perfect.

I'm actually having to do more to this neck than I was expecting. I had to do the last four frets three times, and now it's a little wonky in the middle. But it's getting better.

I have to say that while I think they are cleanly made necks, I dislike the shape of every one I have tried. They aren't players you know.

 

[mongo2]

I have to say that while I think they are cleanly made necks, I dislike the shape of every one I have tried.

I agree, I've seriously reprofiled my personal Warmoth necks save one but that was because I wanted a chunkier neck on my fretless.

 

[SMILEYSIXX]

Wow, this thread went crazy. I "reverse shimmed", as someone called it, because the neck was tilting backwards and rattling against the frets in the higher registers. No, I checked relief, the truss rod was fine. I just tilted it forward a bit. I cut the shim's height by half and the high actions situation has been remedied, everyone can stop arguing now.

 

[mcnach]

Umm....no.......

If you are talking distances and angles of significiant degrees, maybe.
But this isn't the case with a bass neck and the angle of the string in relation to the plane of the neck.

Put the string at a 30deg angle in relation to the neck (X plane) and yes, you will see significant forces/changes in forces as you move from the nut towards the bridge.

I figured 1/4" at the 12th fret with a 1/16" string height at the nut.........0.632deg from X (the plane of the neck)
Give me where that 1/4" is measured from and I'll give you better angles.
Also give me the manufacturer of the string, I'll look up the tension when tuned to pitch, I'll model up a neck in maple with the correct material properties (but without a truss rod) and I'll process the FMA and give you numbers.

My point is, you would have to jack up the action so high to do any damage and given the design of a neck outright, unless the materials used are suspect, it's designed to withstand high action.

Thank you for that.
So many times people talk about effects that may be real, like here, but of a such small magnitude that it can be ignored practically.

 

[SGD Lutherie]

Wow, this thread went crazy. I "reverse shimmed", as someone called it, because the neck was tilting backwards and rattling against the frets in the higher registers. No, I checked relief, the truss rod was fine. I just tilted it forward a bit. I cut the shim's height by half and the high actions situation has been remedied, everyone can stop arguing now.

Instead of reverse shimming it, why not have the frets leveled?

That's like not walking on your broken foot instead of getting a cast put on.

Necks from Warmoth, and even Fender, need to have the frets leveled to play buzz free. Warmoth does not fret leveling at all, and expect people to bring the neck to a luthier for a proper fret dressing.

Invalid Link Removed

Fret Dressing

There are several terms used for this process; Fret Mill, Grind and Polish, Fret Level, Crowning, etc. They all refer to the same basic process of precision aligning the tops of the frets in a uniform plane. Seating the frets in a piece of wood is a difficult process to accomplish with extreme precision. There are usually slight variations in this work and it's further complicated by the fact that the neck woods seldom respond uniformly to string tension. Therefore, a fret leveling operation performed on a raw neck is likely to require further attention after the instrument has been assembled.

It's an accepted fact that final leveling and instrument set-up are best done after the guitar has been strung up to pitch for several days and the neck has time to settle in to the tension of the strings. Then, if needed, the frets may be leveled under tension to provide the finest action. After the frets are leveled then they are individually recrowned to restore their rounded shape.

Most Warmoth necks do not require a fret leveling; they are good to go as they are received. Of course, if you want really low action or a specific feel, an overall setup and level may be necessary. This is highly skilled work and the associated costs can be relatively high, as one might expect for professional services.

As a final note on the subject, maple necks require a finish to preclude neck warpage. The finish is sprayed directly over the frets. It is a tedious task to remove the finish and in many production guitars, it is simply left on them to wear off in use…A fret leveling operation will take this off or the finish may be scraped off each individual fret. Warmoth does not offer either fret leveling or paint removal services.

 

[darkstorm]

Wow, this thread went crazy. I "reverse shimmed", as someone called it, because the neck was tilting backwards and rattling against the frets in the higher registers. No, I checked relief, the truss rod was fine. I just tilted it forward a bit. I cut the shim's height by half and the high actions situation has been remedied, everyone can stop arguing now.

Great. Lol.

 

[SMILEYSIXX]

The bass was refretted about a year ago and had the frets leveled. The neck was leaning back, it was pretty clear to see.