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I'm about to glue the fretboard to my neck so I checked the fretboard face of the neck for flatness with a straight edge and the neck tapered off low on either end of the neck for a couple of inches but only on the bass side of the neck. The treble side of the truss rod slot was flat end to end.

So I figured I needed to correct this so I used sticky back sandpaper (120g) on an 8" quartz leveling block and sanded it down flat. This seemed to work fine till I put the truss rod in the neck and now it stands slightly proud of the neck, bummer.

It's a Martin 2-way truss rod so the TR slot has the rounded bottom which complicates things a bit. Since the neck is tapered and rounded (from Hanalei Moon) there is no straight edge to use as a reference to re-route the slot. Also, the Cocobolo headstock plate is glued in place and inlaid with my logo and the end of the headplate stands slightly proud of the plane of the neck so it won't lie truly flat on the fretboard face.

Any suggestions on the best way to handle this?

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Formerly known as Adaboy.......

Could I use an undersized dowel with sandpaper around it bringing it to the proper radius and sand the slot slightly deeper? What worries me is sanding the slot wider.

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Formerly known as Adaboy.......

This is way beyond my skill-set but if you cut the dowl in half and glued it to a rectangular scrap which is the width of the channel, you could then put sticky sandpaper on the dowel part. You might just round the bottom of the rectangular scrap. I would prefer using 220 grit paper.

I am not sure that this makes sense for your problem but it may start you thinking in the right direction.

Bob

can you cut out a scraper to the right width, a hack saw and a belt sander could get you there. round the end, put an edge on it and scrape to the correct depth.

I think you will get into more trouble with sandpaper.

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http://www.Harvestmoonguitars.com

I don't know if it would be okay to put a very slight dado on the backside of the fret board maybe? It would have to be the exact depth of how far the truss rod is protruding so it is securely captivated, but it seems like it would work. I wouldn't go forward with that though until some other more experienced people chime in. Seems like using sandpaper to deepen the channel would take a lot of work and a lot of trial and error, and it might end up widening the slot a little before you're all done.

Make a "round" scraper to deepen the TR slot as required. How? Take an old screwdriver with a round shaft close to right diameter. Cut off tip and clean up the cut surface on a grinder, being careful to keep it cool (so as not to lose the temper of the steel). Use a hammer to gently swag the end and produce a burr. Presto, round scraper.

I was going to suggest this, make the bottom of the fretboard fit.

Warmoth does this with their ultrathin Wizard neck.

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Old growth, shmold growth!

John, your suggestion to make a scraper is a good one. I didn't want to go to that much trouble, but after reading Tim's post, making one from an old screw driver seems as easy as any other method I can come up with. If I take a little time at least I'll have this tool on-hand for future slots for Martin 2-way rods.

A few days ago, I ground the end of a file down to where the teeth start on my 12" disk sander so a screwdriver should be similar. I ground a little at a time then cooled it in water to prevent it heating so I can try that again. I'm betting the sander will leave a burr.

Unless I think of an easier method or someone posts a better/easier option, I'll give this a try tomorrow.

Thanks!

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Formerly known as Adaboy.......

Tim's idea of a screw driver converted to a scraper sounds outstanding to me. I bet it will make the TR a little less outstanding in short order

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Joe Beaver
Maker of Sawdust

What Tim said.

For those using the folded single acting truss rod, if you want to make the slot a little deeper, use a piece of off-cut truss rod stock and peen over one end a little. Instant round scraper of the exact diameter. Can be used pushing or pulling.

Yes, I have one...

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

If you have any lathe tools, use a gouge to deepen your slot. Use it the same way as the suggested re-ground screw driver.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Yes, scraping is the way to go, and it is amazingly fast, too. I've improvised scrapers in at least half the ways suggested above. Just be careful to leave as much wood as possible between the deepest part of your scraped slot and the back of the neck.

I was also going to suggest this being a good excuse to buy yourself another great useable tool... A router plane!

This is my favorite joinery tool in my shop. It is the most used specialty plane I own. But I have yet to build a guitar so this is coming from a furniture making background.

After thinking about this last night I remembered I had bought some 1/4" rod back when I made a Wells/Karol circle cutting jig. I found it and also found some mahogany type wood that was sent to me as packing material from Hibdon Hardwood. So this morning I took 45 min and made this tool and it worked great! I rubbed mineral oil on the handle.

Thanks for all the tips and suggestions.

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Formerly known as Adaboy.......

Great tool Darryl, now that you have it you will probably find a few more uses for it

Fred

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

Wow you guys are fancy! I would have sandwiched a veneer that matche the purfling between the neck and fretboard to make up the difference.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.