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For those of you who have built a bunch of guitars, do you have a quick check you make to ensure the plane of your neck/fretboard is good? I did a test fit of the neck on my OM last night and with fretboard and spacer for frets, my straightedge just skims the top of the bridge. I want to make sure I can dial in a good low action later without running out of saddle. I can easily take 1/16" off the bottom of my bridge without tweaking the neck angle.

Ken

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yep - I have what I call my tester bridge in the main shop - its a bridge thats about .335 inches in thickness, and I use it when the FB is leveled and radiused but unfretted, to check the lie/plane. I like the Fb to shoot just above it. Thus, once the frets are in, and the guitar is together, I will have a bridge thats about .360-.375 in thickness, with about 1/8 of saddle showing for action.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Sounds about right to me Ken. I find that the Cumpiano and Natelson method works quite well though I tend to err on the high side.

You do actually have to get a feel for how much your guitars move after string up to really know how much the straightedge should clear the bridge.
I usually like to see a little clear space under the straightedge on an unfretted board using a bridge that's pretty close to final thickness. (.344-.360 in my case)
With frets on I usually like about 1/32-1/16" clear space which winds up putting the straightedge just over the bridge under tension.
You can support the peghead and put about 6lbs of weight on each shoulder of the upper bout to get a rough idea of how much movement you are going to get on the fretted neck. If the straightedge is hitting the bridge I'd do a little neck reset rather than taking the bridge below .344
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

This is funny! Here it was just a few weeks ago that few members pm'd me saying that my plans had an error and that the fretted fretboard plane should be flush to the top of the bridge. Even Don MacRostie told me I was doing it wrong that most publications say to set the fretted fretboard flush with the bridge.

The truth is some builders do set the fretted plane flush to the top of the bridge and some the non-fretted. It is a mater of feel and response after string up that will determine what you need to do. However in general if you set the non- fretted plane flush. Then the your finished saddle height will end up fret crown height taller than if you set your fretted plane flush on identical set-ups and action heights.

As for me the way I set my necks and level my fretboards leads to a final product where the plane formed by the top of the frets is 1/16” (+1/16”-0” tolerance) personally I find this a very good rule of thumb to follow but one build will agree and another will disagree. It all boils down to ending up with a saddle height that allows for a good action. Nut slotting also plays a big role here So you see the way you should do it is dependent on how you do everything in regards to the set-up.

Interesting. Sounds like the shallowest neck angle I would want then is one where the plane of a fretted board just clears the bridge and maybe the steepest angle is one where a non-fretted board just clears the bridge. Michael, I am not sure in your response if your 1/16" clearance was strung or unstrung. I am presuming because you say final product, you mean under tension. I don't have a set of your plans, so I don't know what your unstrung target is. Sounds like no frets, just clearing the bridge.

With my OMC, I did some checking when I built that guitar, but I have to admit, I wasn't exactly clear on all the measurements and their ramifications. I certainly have a much better feel this time around, but some of these concepts take a bunch of builds to really understand what is needed. I should pull the strings on my OMC and check it. I like a low action and was able to get the action where I wanted it on that guitar, but should the soundboard raise over time, increasing the action, I can't lower the saddle any more as I tried and the sound just died due to the saddle being too low. I'll be doing a neck reset if that ever happens. I would like this new build to end up with about 1/16" or so more saddle with a similar action, giving me some room to adjust over time. After writing this, I am going to pull the strings on the OMC and do a measurement. This will give me a good datapoint to work from.

Thanks again,

Ken

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