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This is a restart of my build thread for the local woods challenge. It has taken a while to build forms and things so I've really only kicked off the actual building part over the past couple of weeks (mid-October).

Molds, Dishes, Tools, Templates

It took me a while to make the radius dishes. I used a long compass to draw the curves on a template, then used the template to make rails that I ran my router along as I spun double-layered MDF around a center point. Worked okay. It was messy, but doing it outside helped reduce the nastiness.
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After looking at the prices of deep-throat gauges I decided to make this with a $25 gauge I bought on Amazon. I could have spent $15 but this one seemed a little more durable. Glued up some scrap plywood, sanded on a spindle sander and voila! Seems to work pretty well as I used it, some hand planes, and a scraper to thickness my back and sides. I'm not satisfied with my little wood spacer I used on the bottom of the jaws. I originally was going to use a round bolt head there, but it was too difficult to get it perfectly centered using my hand drill.


I made a shooting board not pictured. The white mold pictured in a photo below is borrowed from my dad.

I initially decided to try to follow the free http://www.grellier.fr OM plans. This meant I'd have to build another mold, but after looking at my dad's, I decided to just roll with it. There is some variation in the waist (marked in red over the grellier plans), but the rest of it is very close. I think the mold is built off a template he got from his luthier buddy.


If I get around to taking photos of my tools, I'll post them here.

UPDATE (4/15/2015):

The mold that I referred to before didn't work. It was too tall, and I didn't want to mod a mold that wasn't mine. So I made one. Looking back, it wasn't that difficult and was definitely worth it. Some things I included in this mold was shorter sides, more relevant outside angles for clamping, latches for opening the mold, and dowel for registers to make the mold seat accurately.



It seems to work well. I kinda wish I had a taller one as well. Having access to the sides while kerfing was essential, but at one point I left a set of wet sides in them overnight to hopefully "lock-in" the shape, but the neck day the part of the sides not supported by the mold had warped a little. Not too significantly, but enough to be annoying.

I also made a go-bar deck using some plywood and threaded rod. I used a junk oak board that was warped for the clamping rods, and the natural curve in them seems to lend itself to easy bending. The oak is a little hard and leaves little imprints in the spruce, but that is easily sanded out.



Update (4/21/2015)
Binding tools seem to be quite an industry, and I'm sure I'm about to find out why as I start the binding process. I looked at lmi's gramil and decided to try out an alternative before I went down that route. Here's a circle cutter for a drill press converted in to a purfling cutter. I just epoxied a drill bit in to a section of dowel for a less abrasive register. The great thing about this is that I can switch it back to normal by putting in the old bit, or add on a different register I want to cut rosettes by hand.

The Wood
My back and sides are from a downed black walnut tree from a nearby town.




I've order most everything else off of LMI, including brace wood, a fingerboard, mahogany for a neck blank, purfling, kerfing, etc. I originally bought a cheaper top there as well but after thicknessing it, I proceeded to knock it off a bench and it snapped in two. The good news is my father traded some of his dimensioned black walnut back & sides for some "master grade" spruce tops. Whether or not they're master grade, I don't know. They seem leagues better than what I got from LMI. I'll post a photo of the top I use when I get to that point in the build.

Bending & Assembling Sides/Back
I used a pipe and 500w charcoal lighter to bend the sides. It was my first attempt at bending and I ended up getting some pretty charred spots. At one point I thought I might have to throw in the towel and start some new sides, but I got the burn marks off the outsides and left some residual on the inside. It got down to about .07" in one spot near the waist (with the rest at ~.08"). From what I've seen around the forums, this seems non-ideal but acceptable. This being my first guitar, my instinct is to roll with it.

Looking good so far Zach.

You'll be fine with 0.070" at the waist but make sure you don't over sand after you get the binding in and prior to finishing. Mark in pencil on the side that is thinner "DON'T OVER SAND" or something like that. It will remind you

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Will you tell me the scale length of the Grellier plan please? I could assume 25.34 but we all know about assumption.

Thanks,

-j

That all looks pretty cool to me. You wouldn't believe some of the jigs and fixtures I've cobbled up for one time use....that wind up getting used again and again. Regarding your thickness caliper: Just sand that hardwood "anvil" to a gentle, rounded curve on top. No big problem there.

Hi eigenwood

Will be watching your project with interest. . I am also starting a grelier om from scratch. . My first scratch build so should be challenging (already is !!) Might take me a while to do though.. hope yours goes well and keep posting progress photos please

Cheers

Hey all. For anyone interested, the scale length on the Grellier OM plans is marked 645mm, or 25.394".

So, it's been a long time since I last updated. Not long after I posted pictures of my bent sides, a block of wood fell off my overhead storage and on to a clamp, notching the side out about 3/4".



I went and made another set set of sides and ended up with these:



(For anyone following, I ended up not using this set of sides in this build.) The wood is pretty cool, and definitely appears to have some curl.

I made the kerfing using a ultra-thin kerf Freud table saw blade and a register block clamped to my Ryobi tablesaw's sliding mitre gauge thing. It worked okay, but the dept of cut was a little variable towards the end of the strips, which made it really tough to bend the kerfing consistently. Also, I think a blade that was ground for a flat cut would work better, as the blade I had left the sides of the cut deeper than the middle. This seemed to promote breaking as well.

Since I was still in side/kerfing mode, I came back to my earlier set and started rethinking things. I decided I'm going to try to pull off an arm bevel and make than notch a non-issue. For the second set of sides, I decided to try the laminated "solid kerfing" (<- oxymoron?). I just finished making the bevel support structure. Rather than using a single piece for the bevel support, I laminated a bunch of spruce strips on top of each other, then shaped them in to something arm bevel like. Note to all, I play lefty, so everything will look a little weird.



The advantage to me of using laminated strips instead of a block was that I could just go over the top of my kerfing and still be solid. It looks a little odd, but seems pretty solid.

I also started on the top. The color is a little...unique, but it seems pretty decent otherwise. I used herringbone+bloodwood strips for the rosette. I cut the bloodwood on my little Ryobi and had to use a handplane to get the cut somewhat consistent. It varied in width more than I liked and left some gaps to fill in the final rosette. It's most noticeable at bottom of the rosette.



Next up is to brace the top. The Grellier plans are supposedly "forward-shifted" bracing. Earlier in the build I was making the end block and the general consensus from comments was that "we" had moved on from the large, bulky and now use more of the laminated, thin. Is there any general consensus about bracing patterns?

Braced the top and closed the box. Now it's a guitar-like object.





The sound port was a last minute decision.

Nice work. Looking at the sound port I'm thinking this is a left-handed guitar?

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"Music is what feelings sound like"

Thanks Steve! Yep, it's gonna be a lefty. I'm actually right-hand dominant, but did some damage on my left hand when I was young that makes it tough to play right-handed.

Binding

I was hoping to be done with binding by now, but...

I attempted to hand cut binding/purfling channels with my circle cutter/purfling cutter and a chisel. I was about three days and a nice case of early-onset arthritis in to the channels when my chisel blew through the back. It cracked up a flap about two inches wide. I put some ca glue on it, then clamped it back down, sanded, and it doesn't see too noticeable.

Looking back on the incident, I think was exercising a reasonable about of hand tool skill the first day, but it got progressively sloppier as time went on. A lot this was just hand cramping/fatigue, but also frustration at cutting across the grain of black walnut. I sharpened the cutter head to 2000 grit, but it didn't change much. I tried edging in on the final shelf, starting narrow, then getting wider as I removed material. Not a big difference. I even cut off a piece of a retired block plane blade and ground a narrower angle (20 degrees) thinking that the steep angle (45ish) on the circle cutter might be the issue. It was still ridiculously difficult for me to cut.

So, I'll be ordering a router bit set from stewmac sometime in the next couple of days. I have a laminate trimmmer, but will probably need to devise a jig to hold the thing. I like the simplicity of a parallelogram or drawer slide for vertical motion, and a mount board for moving the guitar in to the bit.

When cutting channels by hand, first focus on getting through the plate. Score, chisel, score, chisel, until you're down to the sides/linings. Then you don't have any changing grain direction messing with you while you clear away the side material. Carefully chiseling away side/lining material and squaring up the channel is the time consuming part for me, and is indeed pretty hard on the fingers.

Probably says something that I've gotten too lazy to do back binding on my last several instruments Although I think I hate the bending even more than the channel cutting. Maybe someday I'll switch to the heating blanket bender and router based channel cutter like everyone else...

Dennis, I applaud your endurance. I didn't even last a single instrument by hand.

The bit and bearings from Stewmac are supposed to arrive Saturday, so I threw this together today.



Overall it seems like it will work well enough. I figure I can handle a body depth up to about three feet. The drawer slides I bought were a little long, but they were heavier duty than the alternatives. I initially wanted to use a pulley/counterweight, but I have this spring on hand that seems to handle the load well enough. I'm only borrowing a laminate trimmer right now, so I was hoping to build the thing with this plunge router. I'll probably turn a donut for the rim to ride on sometime tomorrow.

I've been using Robbie O'Brien's course to guide me in this build. It's been pretty helpful, and one of the things he uses is this neck jig. I used the plans to build this yesterday.



I think the main feature is the utility of the pivot board to hold the neck at the correct angle when routing the tenon. I guess I'll find out for sure when I use it.

Finally finished the binding. After making the binding jig, I had to extend the purfling on both sides of the binding to clean up my "by-hand" binding attempt, so it ended up being a lot busier than I originally was thinking. I used made a maple/bloodwood/maple purfling for the sides and used a b/w/b I got from LMI on the top and back. The binding is indian ebony, and the heel graft more bloodwood.

Since the last time I posted I've glued up the neck, cut the mortise/tenon and bolted neck, cut/tapered the fretboard, bound the fretboard, glued the fretboard, cut and bound the headstock/peghead, drilled the tuner peg holes, and started carving the neck.

Finished in June.

Now that I've had this thing for about 3 1/2 years, here's my longer-term feelings about the design choices I made:

I'm really happy with:

#1: Walnut back and sides. I thought I might regret not using EIR. But I don't. It has great tone, and I like to be able to tell people where it came from. I feel connected to my dad when I play it.

#2: The arm bevel. I like this a lot. Especially after playing other instruments. It probably wouldn't be perfect on every guitar, but no regrets there.

A few things I would do differently:

#1: Ditch the assymetrical fretboard extension without actually adding an extra fret. I think I thought it looked cool at the time, but looking back on it, it just seems a little odd.

#2: I wouldn't have done the soundport. I'm still up in the air about the difference in sound. From my personal tests, it lets a lot of the sparkle/airiness of the treble hit the player, but it also loses a bit of punch. At least that is my theory. And maybe this is really where I am at with the soundport. Sometimes I like it, and sometimes it is like a have a big hole in my guitar.

#3: Less complicated binding. Maybe just ebony, and no other strips. The biggest mistakes you can see on the finished product are where I botched up the maple/bloodwood/maple trim on the side. And the maple/ebony trim on the top ends up making the maple look a little dirty. For someone tackling their first binding, I would tell myself to just use a single piece of binding. Probably what I will do next build.

#4: Keep the top thicker/ I think when I was in the middle of the build, I was correlating thin top with responsive top. That was probably a mistake, and the result was that the guitar has a harder time with keeping up with chord strumming, or heavier attack. At least that is my theory of what I'm hearing.

When I look back on this build, I think what I ended up with was a good-sounding instrument. Maybe not great-sounding, but better than I expected when I first starting dreaming a build.