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Ok, so while money is still tight, I decided to make my own version of the neck centering jig. It took all of about 10 minutes. In fact it took longer to try and draw this picture than it did to make it. This is really based on all the different versions I have seen. For the beginner that does not already own the fancy version offered by our sponsers, this one may work for you.

This is used to place on the neck/fingerboard to align the neck to the centerline of the guitar before attaching the neck perminently. This can also be used for neck resets or even electric (solidbody) rework etc. This was made all from scrap woods and seems to work perfectly.

The dimentions of the brackets do not really matter as long as the hole in the center of the two brackets is perfectly centered between the two outer holes. This is essential to making this work. To make it easy, choose dimmensions that are easily devideable. Example: Make the first bracket 2.5" long so the center line is 1.25" and the edge holes are 1 1/8" from center. Do the same for the larger bracket. Make sure that the small bracket will fit over the fingerboard closest to the nut. If you are using an 1 3/4" nut width, make sure the smaller bracket has at least that much clearance between the two post sticking downward. Make the larger bracket so it fits somewhere around the 9 or 10th fret if using it on a flatop. I am using it on an archtop that has a floating neck extension, so the fingerboard sits above the body. In this case you can go a little further down the fingerboard. I think mine was set at about the 12th fret. The two end dowel rods point down, the center one points up. You can glue them in if you want..but the rod fits tight so you may not need to. The only ones you don't want to glue is the holes in the centering rod. Those need to piviot.

I drew a center line all the way down the flat stock bar and even cut a point at the end of it. This makes it pretty easy to quickly see where the neck sits in relationship to the center seam. The length of the centering bar can be determined by the size of the guitars you build. Because this jig is complete adjustable for different neck widths and tappers, find a length of the centering bar that works for most of the guitars you will build.The closer to the end of the top you reach, the more accurate it will be. I tried this on several accoustics, an LP and my archtop. Seems to work well with all of them.

To double check your accuracy, attach the jig to the guitar with the brackets spun one direction. See where the jig lands on your centerline. Then spin the brackets the other way. They should end up on the same point of the centerline. In fact in theory, you should be able to spin the brackets in any direction combination and the center point should end up in the same place. If they do not...than one of your centering holes were not accurate.

Here is a terrible drawing of it. Remember: the dimensions can be change (an may need to be for your particular use) but the center dowel hole must be centered between the two outside dowels.

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Joe

That design will not center accurately on a tapered fretboard.

Joel,
Been there, and done that, and it won't work on a tapered board. Not to rain on your parade, but our original CL Finder was this exact design, and we had to redo the design to our new design. The posts need to move straight in and out for you to center on a tapered board. Barry is correct when is says it will not be accurate.

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Tracy
http://www.luthiersuppliers.com

Barry is right.

This will only work to find the centerline of a board which is not tapered. The posts don't allow for centering on a tapered board because they are not the same distance from the center of the board in their respective locations. It will be close, but not close enough.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

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Thanks for the feedback. Not raining on my parade at all nor was I trying to short-sale our sponsers. Just looking for a $3 solution for a $50 problem.

In a way I compensated for difference you mentioned and in a way I stumbled on it by accident too.

So while I understand what your saying, with careful layout of where you located the second bracket, I have found that it is within about 1/32"-1/16" accurate over the approximately 30" of length. I am sure that the Luthier Supplie is 100% accurate over the distance due to the updated design. That design (while excellent) is not easily duplicated (thankfully for you) by the hobiest. So I needed to come up with something close enough. With the bridge only approximately 25" from the starting point it is within aproximately 1/32" of being perfect. For now, I think I can live with that on the archtop. It was closer/easier than the ruler clamped to the fingerboard method I was trying earlier. Its difficult to clamp a flat ruler to a curved fingerboard without it sliding out of center.

Here was the details I left out while building it: Place the first bracket on the neck and slide it to where it stops. Place the second one on the neck and slide it to where it stops. Measure the distance between the two and make the holes in the center bar to that measurement. Now the centerline is perfectly center on the fingerboard and guitar and is very close to 100% accurate. Now if the fingerboard has a slightly differnt taper you must spin one a little in one direction or the other. The taper over that short of a section of fingerboard is very small due to bracket being close to pefect in size and shape. My quick crappy math shows that a 1/4" tapper (1/2" total side to side) of a fingerboard aprox 18" long is about 0.027" per inch change in size. If the two pins are only an inch scewed from each other when cocked the difference appears to be minimal. This was double check by spinning the brackets both dirrections and marking the centerline with a pencil. The two pencil lines were almost perfect. The first time I tried this the second bracket was way to larger (spread apart) and it scew by several frets. That gave me a difference of just over 1/16". By making it smaller to more closely fit the location of the fingerboard, it became more accurate. (less scew).

BTW: I did not know this was a design you used to sell. So I hope I didn't offend you by trying to come up with a simular concept. The bob benedetto book has something simular in design, but I think the brackets slide instead.

If you guys feel we should delete this post, go right ahead. I certainly don't want bad info online. I was just trying to share a method for those of us that can't afford to buy every tool for sale for this or any process. It seems everyone is quick to offer solutions that you can purchase...but before those solutions were available for sale, luthiers were doing things on thier own.

Thanks for the advice.

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Joe

Joe,
This is good information, and I do not feel that you are trying to short sale me. Our products are used for someone who doesn't have time to make their own jigs, and want something that is accurate and repeatable. So sharing your jig with everyone is a good idea. People should see and think about other ways to do things.

On another note, on my CenterLine Finder page, I actually show how to use a manual method for locating the Center Line in relation to the neck and bridge. Anyone can use this method to locate their CL and their bridge location. Hope that helps. Good luck with your product, and look forward to seeing the final product.

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Tracy
http://www.luthiersuppliers.com

You beat me to it Todd. This is the method I use, except I use two straight edges at the same time, one on each side of the fretboard. It's 100% accurate and didn't cost me anything extra (I already have tape and straight edges in my workshop).

Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Ok I agree in the yard stick method without a doubt being less inexpensive, and I agree that you can be as accurate. But the issue I always had with this method was insuring that the datum index point of the yardstick was at the exact nut edge perfectly when I measured at the bridge location. It always wanted to move just a tad. I over came this by being attentful (not a real word) and measuring and marking twice to make sure I had not let the datum point move. Then there is the issue of if the yardstick is index scribed on both edges. Mine is scribed on one edge which meant I had to read backwards on the left side of the guitar. (Not difficult but a chance for error).

I am not knocking this method at all I am only saying that I find the luthier supply centering gauge to be extremely accurate and very convenient to use. Not a better method but in my eyes much more convenient and just as accurate.

I have Tracy's centering jig and its well worth the money. Save yourself the trouble and get one....

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

I've been setting the location of my bridges from the 12th fret and not the nut (as I compensate the nut to 1st fret). So on my Luthier's Supplier centering jig, I scribe a line at the 12th fret and where the front of the bridge goes (my saddle slotting jig locates the saddle from the front of the bridge). This way I line up the scribed line on the center of the 12th fret and place the bridge locator on the scribed line for that than just locate the bridge.

As far as ensuring the neck is centered on the body, the luthiers supplier jig is fast and easy, no need to pull out the yard stick or worry about tape. But when I didn't have it, I also used the yard stick and tape method, just took alot longer.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I have the LS jig as well and take a nice deep relaxing breath as I use it. Great tool! I would love it if it had some way to register the bridge locator to the common scale lengths. Perhaps a pin and locating holes? If it did that I think it would almost be cheating. Anything that gets that bridge in the right spot with less fuss would be worth its weight in gold to me.

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Gabriel Regalbuto
Carlsbad, California
Freedom 35!

As soon as Tracy comes out with the ukulele model I am SO there! I had some trouble with this on my first build and will be more careful this time but that sure would make it easier. Did I mention I can be a beta tester for the uke model

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Zac

Anchorage Alaska

Finshed my 1st! See #1 here

That jig will work fine on a tapered fret board. Use it and make a mark, then reverse the position of the contact dowell pivot thingies and make another mark. Dead center is between the marks.
Link

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Cut to size.....Beat to fit.....Paint to match.

LVC....right on! Mine was truely off less than 1/16". It touched the centerline on one edge and then I spun it around and it touched the centerline on the other edge. The center line was about 1/32" wide. Also that was all the way to the end of the top. So that is a full 5-7" futher away from the bridge area. It is that much more accurate the bridge area. It works best if you make it with a particular taper in mind though. Keep the brackets small and close to the right sizes without spining them much.

I do completely understand what the guys were saying and if I had an extra $65 to buy the LS version I would. But in the meantime, this works just fine if you understand how to use and its limitation.



Joe

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Joe

Joe,
Another tip for you that might help if you are using the exact size taper on every fretboard...Just add tape to the 2 inside or 2 outside posts until the centerline lines up. Then for that taper, it will be 100% accurate everytime, and you don't have to mark the outside and inside of the lines. It will be right on center. Good luck, and hope it works our for you!

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Tracy
http://www.luthiersuppliers.com

I also use and am more than happy with Tracy's centering jig. It makes centering the neck almost fool proof.

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866