By nature, a solid neck joint and higher bridge is louder. It's a win-win. I wouldn't be replying (as above) if I hadn't gone through all this myself, on a banjo that retails for $4.5K. Just because it's new, or expensive, or made on a jig, or laser cut or whatever, and assembled by robots or non banjo players, or even banjo players or skilled craftsmen, doesn't mean one bridge fits all. No disrespect to anyone, but I'm scratching my head to all the different ways to raise action (after proper set up checks), other than the raising the bridge. In the guitar world, you install a higher saddle, or with an electric guitar, you raise the bridge segments. Works the same with a banjo.

I'm not talking about correcting a manufacturing defect or warped neck, or warped pot, or miss drilled neck/rim, etc... with a special bridge. All I'm trying to say is that things are manufactured with tolerances and can be slightly different. Once the lightbulb came on and I learned that you can take a well built, solid banjo, as I believe is the OP's case here, and custom fit a bridge specially to that banjo... I've never cranked a co-rod, shimmed, or smoked a truss rod since. Of all the issues we banjo players face, low action on a properly set up banjo is the easiest to fix, and the most welcome opportunity to get the extra kick a taller bridge provides. OK I'll shut up now :)

Edited by - DeanT on 02/08/2012 10:03:32

No disrespect, Dean, but bridges tend to come in increments of 1/16" (some less) whereas the shims we're talking about can be measured in the hundredths or perhaps even several thousandths of an inch. I'm more inclined to use a sandpaper-thickness shim than I am to screw up a bridge that was designed for that size and weight. Precision action adjustments, to the tolerances to which I'm referring, are extremely difficult to nail with a bridge and relatively easy to nail with a thin shim. In fact, I will frequently go with the next higher, or lower, increment bridge and then fine tune with a thin shim. So I don't think it's necessarily a case of either-or (bridge vs. shim) as much as it may be both bridge and shim....as need be.      

If you have .015 that's good.

Wow!  A lot of differing views.

As an idiot who has no business working on banjo's, here's my POV.

Don't screw with the rim / neck interface.

My solution:  Higher bridge.  I cut the feet on mine for accurate height and break angle, Added relief... maybe up to twenty five thousands at the seventh fret.

Finally, I'm now working with co-ordinating rods on my 70's Vega Tubaphone.  It's been about a month since I dropped the action at the twelveth fret from 122 thousands of an inch to 110 thousands.  Measured with Webber gage blocks.  

quote:

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Originally posted by steve davis

If you have .015 that's good.

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Yes, Steve, I thinking that you would not look kindly if I glued a popsicle stick on the bottom of one of your bridges to raise the action. Likewise, your response would be pretty much the same if I put one of your bridges on the belt sander to remove 1/32" or more from the feet. You'd probably get in your car, drive down to CT, and hurt me if I pulled a stunt like that!!

John: The neck/rim interface is what sets the action for a given bridge. Obviously, it depends on your skill set. If you've got a lathe in your basement or garage and you're comfortable doing this, then ultimately, this is the proper way to make this correction.....with the heel-to-rim interface because this is the way it was supposed to be done when the instrument was built.  

Let me go back and rephrase this so we're all on the same page.

In a perfect world, we would all have perfect neck-to-rim interface for the bridge we like to use. A shim is a response to the fact that it's often not a perfect world and to this point Dean is correct. I would prefer, as would most people, to have no shims. But sometimes, if you don't have the skill set to reset the neck, shims become a useful compromise.

Edited by - dickinnorwich on 02/08/2012 11:42:00

just to had more to this already interesting topic when i put back the resonator on it didnt fit well i had to push a bit so, i would assume that something had change. is it the rim that started to become oval a bit? so if that s the case let say that the tone ring is strong enough to stay in shape but at the heel the rim would have shrunk a bit and thats why the shim is needed to give back the proper fit rim neck
lets try that for a cause !!!

quote:

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Originally posted by eric cash

just to had more to this already interesting topic when i put back the resonator on it didnt fit well i had to push a bit so, i would assume that something had change. is it the rim that started to become oval a bit? so if that s the case let say that the tone ring is strong enough to stay in shape but at the heel the rim would have shrunk a bit and thats why the shim is needed to give back the proper fit rim neck
lets try that for a cause !!!

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Eric:

We need a time out.

I went back and read Steve's question about whether you bought this new which you apparently never answered.

Now, as I understand it,  you're reporting that your rim is out of round but in a way that could only be explained by someone cranking down on the coordinating rods in order to lower the action. In other words, your rim is shorter longitudinally (front to back) than it is laterally, side to side. Is this correct? .......and that the shim is necessary to correct for the out-of-roundness?

Edited by - dickinnorwich on 02/08/2012 13:03:49

ya got it new and the rim seem exactly like you mention but not by much cause a business card did it.

quote:

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Originally posted by eric cash

ya got it new and the rim seem exactly like you mention but not by much cause a business card did it.

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O.K., then in my humble opinion, if your rim is out of round only the thickness of a business card (a great shim, BTW), I'd walk away. The neck heel doesn't need to be shaved. You've solved the problem. And forget whatever anyone tries to tell you about a shim: In a blind test, you will never hear it. Much more important is that your action is correct and there is no fret buzz.

So much banter about such an apparently easy fix. DeanT hit the nail on the head. If the setup is otherwise correct (head tension DDs at 93, neck is straight or slightly relieved, coord rods are neutral) and the action is too low, put on a taller bridge. Problem solved.
Then the OP, Eric, says the reso doesn't fit any more so the rim must be out of round. Not likely and it would have little or nothing to do with the action if it was. The reso only contacts the rim at the L-brackets. It would have to be out of round like a quarter inch to make any real difference in how the reso fits.

Edited by - drifty on 02/08/2012 16:25:16

>Yes, Steve, I thinking that you would not look kindly if I glued a popsicle stick on the bottom of one of your bridges to raise the action. Likewise, your response would be pretty much the same if I put one of your bridges on the belt sander to remove 1/32" or more from the feet. You'd probably get in your car, drive down to CT, and hurt me if I pulled a stunt like that!!<

Just making sure you guys know, that I know, that the popsicle trick is not a permanent fix :). It was my way of making sure that the taller bridge would work, and making a template for proper bridge height for my banjo. I still use that bridge today as my template for making bridges for that banjo, and I also use it as a "bridge-jack" when fitting a new bridge. I could never see anyone gluing a popsicle stick to one of Steve's bridges, or sanding one down. HOWEVER, I could certainly see the OP (Eric) gluing a popsicle stick to his bridge, love the outcome, and sending that to Steve to use as a template to make him a new bridge.

>No disrespect, Dean, but bridges tend to come in increments of 1/16" (some less) whereas the shims we're talking about can be measured in the hundredths or perhaps even several thousandths of an inch. I'm more inclined to use a sandpaper-thickness shim than I am to screw up a bridge that was designed for that size and weight. Precision action adjustments, to the tolerances to which I'm referring, are extremely difficult to nail with a bridge and relatively easy to nail with a thin shim. In fact, I will frequently go with the next higher, or lower, increment bridge and then fine tune with a thin shim. So I don't think it's necessarily a case of either-or (bridge vs. shim) as much as it may be both bridge and shim....as need be.<

This is a good example of different ways to accomplish the same outcome. Once my banjo is together with proper relief and neutral co-rods, I don't mess with it. I can easily spend and entire afternoon dishing, sizing and slotting a bridge to get the strings absolutely exactly where I want them with no tolerances involved. Wood is easy to work with. I also start by making my bridge thicker than a factory bridge. The one that's on my banjo now took several week of playing, thinning, repeat, a bit at a time, until my banjo sounded exactly how I wanted it to. I've never considered shims. I also realize that a luthier, and certainly not a factory, could pay this much attention to every banjo. When I'm done, my bridge leans back for a better break angle, the outer strings are slightly lower than 3/4", the 3rd is slightly higher then 3/4", and the 2nd and 4th are almost dead on 3/4". The bottom is dished so that it will never sag. Why do I do this? Because I found out several years ago, that if I started with a $2 3/4" tall Stu Mac bridge, or a 5/8" bridge with a popsicle stick glued to it....and sized it as described... to a buzzing banjo with low action... my banjo sounded much better than egging my rim or shimming the neck to work with the 5/8" stock and de$igner bridge$ I tried. And I don't have the equipment, desire, nor the $$$ for a heal re-cut.  

My apologies to Eric for straying off topic, but I love this stuff, it's what makes banjos tick!

Edited by - DeanT on 02/08/2012 16:42:48

Sometimes a small, well placed shim can be an easy and effective fix when all other setup options fail. But it should always be recognized that any gaps created between the heel and the pot will rob volume and tone in direct proportion to their size. Some heel cuts are not exactly flush to begin with and a poorly installed shim can reduce the actual surface-to-surface contact between the heel and pot to a couple of high spots of less than 20% of the total heel area.  That means 80% or more of the joint is airspace, which transfers no vibration and impairs the banjo's performance dramatically. In some cases, a heel recut is the best solution, but that is a job that should not be undertaken by the inexperienced. A very small amount of grinding, filing or Dremeling on the heel can quickly throw the fit, action and neck angle WAY out of whack.

"But it should always be recognized that any gaps created between the heel and the pot will rob volume and tone in direct proportion to their size."

HUH?

Drew:

Any science to back this up? This is a huge leap.