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Here's the setup I was using to plane the plates for joining:



As you can see, it's quite ricketty and not square. I think this was what was causing my inconsistencies...or at least partly. I kept getting these gaps at the ends of the plates.





So, I figured that I'd try to create a better shooting board. I ended up taking a spare piece of oak hardwood flooring and mounting it to a board that I mounted to the lip of my workbench. I fasten the plates directly to the workbench (which is covered in cork to protect the plates) with the joining edges sticking over the edge of the workbench just a bit. Here's a shot of the jig with the purpleheart back plates on it.



The hardwood flooring plank worked out great. It's nice and straight, flat and, with the aluminum trioxide finish, it's pretty tough and very smooth. The plane travelled down the board great. After just a little planing, I had the plates ready to join.

Next, I set up my workbench to glue the plates. I set up a dry run first...







I put the glue on and joined the plates.



The plates ended up joined nicely. I was proud. Sorry, I don't have a pic of the finished product. And those are old mouse pads that I have under the toolbox (used for weight). Mouse pads are pretty handy in a guitar shop!!

Afterwards, I got the purpleheart back plates down off the rack to joint them. But I noticed that both plates had cupped a little. I hadnt properly stacked/stickered them. So, I've got them sitting, cup side down, on my basement floor in an effort to try to straighten them back out. Will update...

I've stacked/stickered the back and side boards and I've placed a dehumidifier in the room with them set to 45%. I wet the cupped side of each board prior and placed weight on the boards. They seem to be straightening out, especially the back set. The sides are still quite cupped, but because of their width, I expected them to take a little longer.

I'm in the process of thinning the top. It's going pretty well I think. I'm alternating using the 6" block plane and a flat cabinet scraper. The scraper really only pulls up "fuzz". I suppose that this is normal due to the softness of the spruce. I started with a board thickness of just over 4mm. I'm down to about 3mm now. My target is 2.5mm.

One thing I noticed, when the top board was rectangular, it had a very pronounced, ringing tap tone. But once I cut the board to the general shape of the top, the ringing subsided quite a bit. As I've thinned the top down, I've tapped it to hear the tone, but there's not much there. Is this normal?

So, I've done a little work on the guitar lately. I've joined the back plates and started thinning them.





I took it down from about 4mm thick to about 2.5mm primarily using my 6" block plane and my cabinet scraper. I made a real bonehead mistake...one of the plates was just slightly bowed, so I ever so gently bent it back flat with my hands...then SNAP! I put a nice crack on one side of one of the plates, after they were glued together. Fortunately for me, the crack was mostly outside the outline of the guitar. But it did extent about an inch into the lower bout. I promptly cut away the part of the plate that I knew I wasn't going to need, then glued the crack back together. Note to self...Purpleheart can be brittle across the grain.

I'm still waiting on the purpleheart boards for the sides to straighten up. One has flattened back out, but one is being stubborn. I currently have it sitting flat on the concrete floor of my basement with about 30lbs sitting atop it. The one board that is flat, I cut it down to the approximate length I needed. I need, if I recall, 25 3/8" of length. I cut it down to about 29". I had about a 6"x6" square left over. I've decided to use that piece for the rosette. I used my wife's Cricut machine to cut out a ring on card stock. The inner diameter of the ring is about 90mm and the outer diameter is about 110mm. I traced the card stock ring onto the square of purpleheart. I then took a 2" hole saw on my drill and removed part of the center of the square. I then used my fine-toothed draw saw to cut around the circumference of the outer ring to get it closer to the drawn line. I'm in the process of cutting/sanding it down to the final shape. I'll post pics later.

Please feel free to comment...getting lonely in here!

Here is a pic of the purpleheart rosette partially done:



Here's the finished product:



It was exceedingly difficult to get this thing perfectly round by hand. I used a Dremel tool with a sanding disc attachment to make it. It's not perfectly round, but it is close enough. Last night, I chiselled out the channel with a 1/4" chisel. The rosette is now laid in the channel and the glue is drying.

Hey Andy! It looks like things are coming together for you. I have to say that your bloodletting gave me the willies. I've tagged myself several times with a chisel, once for stitches, and I always feel like a dummy afterwards. Looking forward to seeing more of your build.

Alex

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

Just read through this and it seems like you are coming along nicely. You have had some of the issues I had with my first! Its a great learning experience and believe me number two is ten times easier. Im very impressed by the rosette! You did an excellent job making that ring by hand. Keep up the good work and welcome to the challenge!

Oh and what kinda kentucky boy uses metric???

Yeah, mistakes are a-plenty on this one. I have a nice battle scar to show off though. Note to everyone...SAFETY FIRST. You can't build guitars without fingers.

The rosette wasn't easy to make at all. My original idea was to use two hole saws of differing diameters on my drill. But once I saw the prices of the bigger hole saws, I decided to just try it by hand. I'm just a big cheap-skate I guess. But I really enjoy overcoming obstacles by just using the tools at my disposal, if I can.

So, the rosette ended up okay...the channel is a different story.



It would have been nice if the channel had been an even 1/2" wide. Then I could have used my 1/2" chisel. But the channel was about 2mm shy of 1/2", so I had to use my 1/4" chisel...which was much harder to control. I ended up making the channel too wide. To try to fix the mess, I tried putting spruce sawdust and superglue in the gaps. Bigger mess. So, after much thought, I decided to just rout out around the outer circumference of the purpleheart ring.



I actually took out about 1mm of the ring just to make sure it was perfectly round. I made a 1/4" channel, 0.8mm deep. Turned out pretty good. My plan now is to make a mosaic rosette of white, green and purple wood and fill the channel. I've got the rosette logs made, and just need to cut them out. I'll post pics of that soon.

The inner circumference of the purpleheart ring is still a mess. But I'm not sure what to do about it. Any suggestions? I would rout that out too, but my smallest router bit is 1/4", and that width would infringe on my soundhole opening, which is supposed to have a 42mm radius. Should I buy an 1/8" router bit and rout it? Leave it like it is (yuk)? Make my soundhole a little bigger and take it to the inner circumference of the purpleheart ring? I'm not sure that's on option though. Do you have to leave a little of soundboard material between the rosette and the soundhole opening??? Not sure what to do.

Oh, and we "edumacated" Kentucky boys use metric!

As Todd suggested on a recent thread about soundholes, how about some sticky sandpaper on a funnel for cleaning up the inside of your rosette?

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Good judgement comes from experience. Experience comes from poor judgement.

That's a really good idea.

But my problem is that I haven't cut the soundhole out yet, and the rosette channel is a little too big in places on the inner circumference.

If I were you I'd buy the 1/8 bit and do another ring on the inside. But yes you can take the soundhole all the way to the rosette if you wish. Do a search for "soundhole binding" and I'm sure you will get some pictures. Ive seen plenty of guitars with a bound soundhole before.

Sorry, I didn't realize that rosette was already installed.

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Good judgement comes from experience. Experience comes from poor judgement.

So, I'm in the process of making the mosaic tiles to cover up my shoddy initial try at the rosette channel. Here's the little jig I made to glue them together.



I just routed a 1/4" channel in a scrap piece of cherry. I made a small slat of cherry to use as a caul when clamping. The rosette log I made is sitting on top of it. I also used this jig to cut the tiles.

Here are the finished rosette tiles.



Here are a couple of shots of the rosette tiles laid dry in the channel.





So, I decided to go ahead and glue the tiles in tonight. I hope this doesn't disqualify me from the challenge, but I enlisted a little help with setting them in place.





This is my daughter...for whom I'm making this instrument.

Naturally, she had to take breaks every so often, so I got to try my hand at the process.



Here's a shot of the rosette fully glued in.



I'll let it dry overnight and commence to sanding it down tomorrow. It's supposed to snow all weekend here in eastern KY, so I'll hopefully get plenty of time to work on it.

Using the little jig to cut the tiles...



Note the scar on the index finger. Makes for a convenient safety reminder.

Nice idea - it looks great!

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"I am always doing that which I cannot do, in order that I may learn how to do it."
Pablo Picasso

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So, the rosette is finally complete. Once I had them glued in and the glue cured, I tried planing them down, but I got a lot of chipping and actually had to replace 3 tiles. Not a big deal, but I wonder if maybe I didn't use enough glue making the rosette logs. They seemed to want to disintegrate when the plane hit them. I was going slow and easy, but any pressure from the planer blade seemed to crumble a few of them. But I got it done and went ahead and cut out the soundhole with the router.



I decided to go ahead and expand the soundhole to 44mm and take it all the way to the purpleheart ring.

Next, it's on to the braces. I've got them all cut down to size and ready to glue.





I'm now gluing down the rosette grafts, but will have to assemble my go-bar deck to get the rest.

Here's a shot of my homemade caliper.

Got my go-bar deck built...very happy with it!







I may have overbuilt it. I used 5/8" thread-all bolts, 3' long. Very sturdy. Probably could have used a smaller bolt though. I ended up having to cut my 36" go-bars down about 4" to get them to fit under the deck. I glued my first braces last night.







Got a bit more work to do on the other braces before I can glue them.

Question for the guru's...here is a pic of the bridge area on the Courtnall plan I'm using...



From what I can tell, there's no call for a bridge pad. You'll notice that the "bridge location" area is defined by a dashed line. The other brace/graft locations are defined by solid lines. The "bridge location" area is very big - covering most of the width of the lower bout. I'm assuming, from the research that I've done, that a bridge pad should be installed. What size, shape should it be? Should it be the exact footprint of the actual bridge? A little bigger? A little smaller?

No, no bridge pad. That's not unusual on guitars this size (or larger for that matter - not everyone feels they are needed at all.).

Your braces look really heavy. Are they going to get carved down to next to nothing in the vertical dimension? I'm building a guitar with a top patterned after Torres SE114 right now (a larger plantilla and regular classical scale length), and it has wide and low fan braces, but really low, so it looks to me like you have a lot of brace carving to do.

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Jim Kirby
kirby@udel.edu

No bridge pad? I went ahead and installed one the size of the box on the plans...which is exactly the dimmensions of the actual bridge. It is about 2mm thick right now, but I plan to sand it down a lot.

Yes, the braces are a bit chunky right now and I have a bit of carving to do. The plan calls for the fan braces, the upper cross strut and the V-braces to be 3mm tall by 7mm wide. I sanded them down to 7mm wide, but left them 2mm too high on purpose to carve them. The upper and lower transverse bars are to be 8mm wide by, I think, 15mm tall. Again, I've left them a bit high to carve down.

Back to the bridge pad, I guess my problem is that I'm using Courtnall's plan and the Cumpiano book. I'm sure Courtnall's book would have told me no bridge pad. In my debate on whether or not to install one, I remembered reading somewhere that any time you glue something to the top of the soundboard (bridge, rosette), you should apply a graft to the other side in the same position for stability purposes. Remembering this, I went ahead and glued down a pad. I hope this isn't a huge error. I can always carve/sand it away though, as I've not yet installed the fan braces over it.

For full size guitars, it's pretty much an open question as to whether you want to use none/a regular patch/something even more extreme like a transverse brace under the bridge (Bouchet). I don't think Torres guitars had patches, or at least not regularly. I don't use one one my recent builds (Romanillos plan), and I have no real clue if they'd be any better or worse if I did use one. That would take more experience, which I'm short on.

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Jim Kirby
kirby@udel.edu

I did my Torres bracing guitar without any bridge pad.
It's definitely part of the sound if you are going the Torres route.
The standard for Torres bracing is about 7 mm wide and 3mm tall.

Also regarding the bracing gluing sequence, I wouldn't glue the 2 closing brace (2 V brace near the end block) first, as they will be in the way when u carve the 5 fan brace.
Instead it would be better to glue in the 5 fan braces - carve it then followed by the closing brace.
The last to go in will be the 2 harmonic brace (UTB and LTB)

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Sen CL Goh
http://senguitar.blogspot.com

No bridge pad for this little guitar, take it off. Also, keep in mind that the small guitar does not have a large area and will be inherently strong so that you will be able to build this top fairly flexible.

As Sen mentions, glue in and carve the 5 fans first, then the others. I'd also plane them much closer to final height first. You don't want them to be too stiff when gluing them to the dome established by your solara or they may not take it as they are fairly short.

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Thanks for the advice folks. I really do appreciate it.

I've been working on this guitar a little bit every day for the past couple/3 weeks...weekends and after work. I've been in a really "building" mood lately I guess. And maybe I should be a little more patient...because I've already glued in all the braces except the lower transverse bar, with the fan braces glued atop the bridge pad. I did sand/scrape the bridge pad down to about 1.5mm before installing the fan braces though.





I could remove the bridge pad between the braces I guess...the consensus seems to be that there should be no pad, so I guess I've got a lot of sanding ahead of me.

I actually put the V-braces on first... . But hopefully they won't be too much in the way. I've got one of those curved chisels...this one actually.



I've not used it to carve yet, but I have used it for glue clear-out. Much easier to use than a straight chisel.

I want to thank Waddy Thomson. A few years back I came across his post about building his first guitar over on the Delcamp forum. His post inspired me to try to build a guitar and I probably would never have taken my desire seriously had I not read it.

I'm throughly enjoying watching this come together, it's nice to see someone else working around the tools and skills on hand.
You'll probably be suprised at how good it sounds when you're finished.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Waddy is indeed an inspiration. He and I started out about the same time, but he has put in way more thought and hours since then and now I look to him for inspiration (except for those darned neck laminations - inside joke. And someday I'll remember that his last name doesn't have a "p" in it )

As for choice of chisel for carving brace ends, its actually easier to work with a straight blade inverted, so that you are sort of scooping with an upward sweep as you approach the brace end. But different people find different comfort zones - not saying there is an absolute right answer.

Keep up the good work.

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Jim Kirby
kirby@udel.edu