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This is one aspect of building in which I just cant seem to win. I started off with 12" stewmac blocks and just could not get an even sand no matter what I tried. Putting in a concerted effort to make each pass even and smooth I still would end up like an 1/8" out somewhere... usually multiple places. I then moved on to making a guide for the radius block, which consisted of a base with rails along each side to limit the vertical and hortizonal movement. This also led to uneven thickness. Finally I found a method that was working great for me, I made a reasonably simple jig with a base with a curved rail on each side, and a router base with the corresponding radius. It worked great and would only need a very light sanding after, making a nearly perfectly even fretboard. Well I havn't been in the shop all winter and just broke it out again to find the whole thing out of whack due to movement of the wood comprising the jig, namely the rails. Should I just make another one of these or do you guys have another suggestion for me to try? I don't really want to make one of those complex radiusing jigs.

Which StewMac blocks were you using? If the wooden ones, they're really too short to get a good radius from scratch. They're better for for cleaning up an existing radius, such as during a refret, but I don't trust the wood ones anyway 'cuz wood moves.

I use the 18 long aluminum beams that stewmac sells, and get excellent results. They're long enough to cover the whole fretboard, and are machined very accurately. It takes some skil and practice, but you can radius a neck perfectly with them from scratch.

I rough my fretboards in on the belt sander first, then finish with the beam.

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Old growth, shmold growth!

Ed: Make a accurate gauge out of thin sheet metal and check your progress as you sand. Also watch the four corners of the finger board to make sure you are taking material off equally and also check with straight edge along the length.
Tom

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A person who has never made a mistake has never made anything!!!

I made a 36" sanding board using a stable, heavy board (you could use square alum extrusion). Glued straight 1/4" dowels 3" apart down the board. Then filled between with bondo and, with a 12" radius scraper riding alond the dowels, scraped out the bondo to produce a constant radius block. Glue on 80 grit, clamp in vise & sand fingerboard along it (mine are already glued to the neck), closely following Todds advice re marking/assessing often!

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Dave
Milton, ON

Using a 8"-12" block, I have given myself grief before that I figured was due to not keeping the block aligned with the fretboard. I tape a 2 foot dowel or other scrap on the back of the sanding block to give me a visual aid to keep from rotating it while I sand. Helps a lot.

Also, it helps when you realize that you can spot sand. You do not need to sand the whole board every stroke. Check often and sand only where it's needed.

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Mike Lindstrom

Use pencil to mark the board. Line down the middle and some equal distance from each edge. Gives you visual feed back and informs your hands to what is going on. Makes it pretty easy.
L.

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

Yes it was the 12" stewmac wood block I was using. I don't really want to shell out for the aluminum version, although I can see it being a good investment.
I thought my technique to be adequate, although the results told differently. Perhaps 1/8" was a slight exageration, but there was unnevenness everywhere.
I would mark the board with a pencil and take long, even strokes from beginning to end taking care that the block remained as straight as possible as well as maintaining even pressure.
Usually I am pretty good at these kinds of operations so the frusteration was considerable...

Another question, is it best to inlay before or after radiusing?

Thanks guys

Lots of good advice above, I'm sure you'll get the technique. As far as inlay, I inlay
after the radiusing, leaving the inlay just proud of the board. I use a fine file lying
flat along the length of the board to bring the inlay down to the wood level. I use a
router, plane, and scraper to radius the board, and I don't trust the router and plane
to not chip the inlay.

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Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

Perhaps I'm stating the obvious, but you absolutely must stick your sandpaper to the radius block (I use thin double sided tape). Trying to use these as a simple backing block with loose coarse-grit paper is asking for trouble -- the paper so stiff it will remove material even in places where there is little direct pressure. My Stewmac blocks have 80 grit paper and I use them only to profile the radius. I usually use two of them to produce a compound radius. Like Todd, I profile my fingerboards on the guitar. The tips he gave earlier ensure you remove material evenly and only where needed. The final shaping, blending of radii and removal of grit scratches is done with finer grit and a flat-bottomed cork block.

I always inlay after profiling. Perhaps not so important with MOP, but I'm often using paua ablam and want to install the shell only a hair proud of the surface so I have control over the shell figure that will be visible after final leveling and polishing. If I remove too much shell, I'm into another layer in the ablam and a totally different figure and colour.

Edward,
Been there, done that! I hate radiusing finger boards more than anything! I finally developed a jig that is easy to use, but you will need to have thickness sander to use it. Here it is: http://www.luthiersuppliers.com/products/p12.html

Or you could add on to this jig buy building 2 walls on each side and make a rest for a router on the top, so instead of using a thickness sander, you could use a router with this jig. Michael Bashkin has one of these and that is how he uses it.

Jigs are a pain to make, and that is why I sell them, so help others! Good luck!
Tracy

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Tracy
http://www.luthiersuppliers.com

I'd feel better if that last picture showed the entire end of the fretboard so we could see if t were lopsided or not after using the jig referenced in the previous post

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Old growth, shmold growth!

Also those stickit gold sandpaper Stewmac sells, they might be expensive but are almost a must when using those radius blocks.

They last longer than the 3M fre-cut sandpaper for some reason. I wish there are cheaper source for those sandpaper though.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

You should be able to get close enough just using a block plane, then switch to the Stewmac sanding blocks.

There is no need to show the whole fretboard because it is perfect after about 5 passes. I've sold about 40 of these jigs over the last year and a half, and no complaints. The only feedback I got was that this was the best jig they have ever used.

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Tracy
http://www.luthiersuppliers.com

I have a problem of the block plane causing tear outs on the ebony, I suspect its because of the low angle of the block plane, unless its because I set it up wrong.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I suspect you are correct.
A high angle block plane would be better, or you could try honing a higher angle secondary bevel on your low angle blade and closing the mouth right up.
if you had a spare blade it would be a bit like having both high and low angle planes just by changing blades

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.