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Not much to show for the past weekend. Seems some young man in the family took the memory card out of the camera and didn't replace it! I was confused when the camera kept saying "Out of memory" when i knew i had just deleted a bunch of photos...

So the number of pictures is limted to what the camera had for internal memory. I guess i'll have to whip out the old family pictures from the trip to santa's land in '75'. Set for a spell!!

Most of the day was spent thinning down the sides to between 1.8 and 2 mm. After bending the first side in the form and finding it had too much Springback we re-did it and it held a lot better. No pix though.



I really thought the fugure popped when i started scraping.
Lesson learned: The edges of the wood gets really REALLY sharp when scraping... there will be no doubt who built this guitar if they ever do a DNA sample of the wood.

A closeup of the figure on the sides. I am getting antsy to see this under finish...


Lastly, we where chatting about the fretboard and what to use. I was thinking about using some grenadillo (Sp?) wood but it really didn't do too much for me and when i went to LMI fro some classic black ebony they were not guaranteeing they would be well quatered, so we decided against that. Happened that AL remembered some old Madagasgar Rosewood he had been given and since he can't use it due to cites restrictions he decided to offer a piece for this guitar. I thought it was quite nice! A bit like the Ziricote but much more subtle figure and a color match for the redwood burl rosette, so i think it'll look great. I was'nt sure about the sapwood run along the edge at first but then i decided to whoop it up!

Here's a picture of the mad rose...

That's it for pix folks... now, if you put your feet up while i get the 8mm projector setup... you've never seen such great movies of a kid up-chucking on Santa... They're soooo cute.

Hey where'd everybody go?

I like that Mad Rose FB! I lost almost an entire build's worth of pictures once when my Mac didn't play nice with my memory card. Bummer!
Looking gray so far. I don't think any of my instruments is missing DNa from me:)

I love the low-tech way you're going about this. Looks like a lot of work, but probably also really connects you to the work and with a much smaller financial investment. I'm enjoying your progress.

James, I'm not so sure about the smaller investment... have you seen the price of Ziricote and LS Redwood?? I'm just glad i bought them years ago.. I'd have to think twice at current prices.

Seriously, I agree. The connection to the work is as important as the end product. I am having a blast and wish i had more time to dedicate to this. One day a week isn't enough.

One advantage of low-tech, aside from the lower tooling cost, is that I never heard of anybody taking off their arm with a 5/8" chisel. It also seems to me that hand tooling is the basis of understanding what you're doing. Once you know how to make something by hand you can figure out ways to do it with a machine. I'm not at all sure it works as well the other way.

Been a couple of weeks since i posted last so i figure i better get to it. Not a lot visually to see but it must have been a lot of work because it took two days.

First, the sides have been bent. It was more difficult than i though this would be. Al also convinced me to forgo the cutaway because it would be a bit difficult for a first guitar and he had some comcerns about the ziricote being rather brittle. Since it was mostly a case of vanity - because i don't play that well and never figured out why there are so many frets anyway, i was ok with that direction. It seemed a good ide once i started bending the sides...

After we bent to the form, Al had me tweaking the side to better conform to the mold. My initial tries resulted in more bringing the sides back to their original flat state than getting closer to the end form. Al started to show me how to over-bend the sides and to be patient and let it cool before starting the next spot... and then the magic happened.

There's an early thread where someone wondered what the result might be if the right-brained padma touched the fingertips of the left brained Al Carruth. Well, i can attest Al is not devoid of right brainery... As he was showing me how to over bend on the shoulder the sides decided to speak to AL and just kind of melted in his hands. It told him it WANTED to be a cutaway. It was one of those moments that made it worthwhile to watch a master artist at work! I have decided the guitar will have a woman's name since it was obvious it both wanted a cutaway but wasn't going to make it easy. I watched as Al resorted to a few secret incantations that i have'nt learned yet, mixed in with a few old sailor curses which i have NOW leaned and gave that girl some curves as sulty as any i have seen.


One of the suprising things about the wood is how brittle it is. It tends to do two things:
- Split rapidly along the grain
- It tends to crumble under a chisel if take too deeply.
With those two things in mind, I used a chisel to reduce the sides for the wedge only to a certain pooint and then switched to a plane. There were a couple of spots where i was afraid using the chisel might cause it to crak in a direction i didn't plan on going.


I did manage to crack one side when i was planing a bit too quickly and whacked the cutaway when planning the opposit side towards the cutaway. It cracked as soon as i touched it about two inches from the neck towards the cutaway. Some quick CA wicked into the cut made it invisible. Al then glued some tiny block to help keep it from cracking under my abusive attack with the plane.



Here's the final look after the planing the wedge.


Last pic is just the tail block being glued.


So that's where she stands. And i'm still having fun!

Rob,
looking good - glad the cut-a-way worked out!

Looks good! I recently did a wedge with ziricote and I had some cracking issues. I cracked the side, but CA saved the day and the owner has reported that there are no problems so far. Ziricote really seems to enjoy cracking along the dark grain lines. I guess that's why it is often called Mexican crack wood. Keep the pics coming.

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http://www.CostaGuitars.com
PMoMC

Tony.. i think the mexican crackwood is a bit extreme. It cracked because i whacked it from the side... i was simply not being patient. It did seem to want to split along the grain lines. It's a bit hard to see in the pic with the chisel, but to the left of the chair leg there was a knot and i coult tell it was going to try to split around the knot if i kepy using the chisel. It's almost as if the wood has no fibers across the grain.. at all. Not a problem when paying attention. The name likely comes from the addictive need to buy more!!

Nice progress, Robert! How did he have you measure the width of the sides for the wedge? I'm wondering if I can build a wedge into my current guitar. It's at the same phase as yours is in the above pictures, but I don't know how to mark for the wedge and how much and where to remove the extra side width.

Beth:

OK… This is a s best as I can remember. PLEASE, please check this with someone before you do it since I may miss a step. DISCLAIMER: I tend to daydream and miss details. Make sure this makes sense and you verify with someone first!
Here goes… (wish I'd a known there was a test when I was doing this!)

Keep in mind the top is flat it’s the back that takes the wedge.

Both the front and back were brought down to fit to the radius dishes. I think Al has a 15’ radius on the front and 28’ on the back.

WARNING: I think at some point we had to ensure the top was perpendicular to the sides. But I forget when and how we measured that.

With the back side down in the dish, we placed spacers under one side to raise it the required distance. I went somewhere between ¾ and 1 inch. I forget the measurement at this point. Al measures in MM and I still think in inches so I never remember.

Couple of things to remember. The thin side is towards you. SO whichever side is going to be facing you when playing, that’s the side that will be down against the radius dish, and the thick side will be raised. On mine, the cutaway side was raised off the dish.

And so we have some parameters to work with, lets say we have/want the following:
- Thick side will be 4 “
- Current width is 4.5”
- Difference between the two sides is 1 “

Here’s what we did:
- Raise the cutaway side 1” Or whatever is going to be the thick side….
- Make sure the centerline of the guitar is raised the same amount at both ends
- With a ruler, start marking all the way around the inside of the guitar 1.5 inches from the dish face up the side. So on the raised side, the line should be ½ from the bottom (back)) and 1.5” on the low side (the thin side) Ugh, I hope that makes sense.

So at this point there’s a nice line around the inside and you should be able to see the wedge.
Now, flip it over so the back is facing up. From here you’ll shave down to the line.

Al doesn’t use sandpaper on his dishes (at this point anyway) so what he had me do was to put chalk on the back radius dish and after I planed it down to the line I would then flip the back down into the dish and wriggle it. Then I'd flip it over and shave down anywhere there were chalk marks. I keep doing this until the entire back gets covered in chalk at the same time so I know the back fits the radius dish. The thing to remember is when shaving you are working face down on the top dish and when checking your work you are back down in the chalk on the back dish…

So what you see in the photo is the back side sticking up and the front is face down on the top radius dish.
I hope that is correct and makes sense. If anyone sees that I’ve screwed up Please speak out. I only did it once and there has been much holiday cheer in between!

Good luck!

Well, I'm certainly not an expert, but I have built two wedge guitars and the process Robert describes is pretty much spot on. I did a more severe wedge on my last one, it was a 1.5" difference between the bass and treble bouts.
Beth, if you are having trouble, I would be happy to walk you through the process. PM me if you need help.

_________________
http://www.CostaGuitars.com
PMoMC

Robert, thanks for taking the time to go through that. Makes perfect sense!
Tony, thanks. I do have a question and will PM you if I can't find the answer

Tony, I have read that some people will take 3/4" off one side and so as not to affect the volume of the box, add it to the other for a total of 1.5" difference.

Beth... I know it's great to get an instant answer but to my way of thinking it helps us all out to post questions to the forum. Who knows, I may have the same one... so i'd urge you to post your question here too if you do end up PMing Tony. Good luck!

I use the common 25' radius on top and 15' on the back. As Rob says, all the taper is in the back.

He bent his sides at full height. Start by making the edge of the side that will be toward the top flat, and when you bend, make sure the bends are perpendicular to that. The object is to have the sides go into the mold and sit flat on the bench top all around the top edge. Some bending irons get hotter on one end than the other, and tend to bend cones, which will drive you wild...

Once the sides are trimmed and in the mold, held in with turnbuckles across the width, and a stick along the length, you can dress off the top surface to fit the dome. Just put the thing top down on the mold, and use a marker of some sort (we may have used a white China marker) to scribe around them, holding the marker off the surface of the dish by the height of the biggest gap; which will probably be at the waist. Trim to the line by whatever means suits, and check it in the dish. It helps, before you start, to mark a level line around the outside of the sides along one surface of the mold, so that you can push them back into place if (when) they slip. I used chalk on the mold surface at this point to find the high spots, but don't worry too much about an exact fit. Later, after the liners are in, is when things really need to be right.

Getting the back angle is a little trickier. I have numbers on the mold that tel me how deep to make the box at either end: it's usually around 105mm ad 90mm on a steel string. When the top surface is right, I measure down on the center line at each end and mark those depths. On a normal guitar I would just shim it up on the back dish in such a way that the two depth marks at the ends are the same distance off the dish surface. Then I'd scribe around the edge, using a marker that was held above the dish by that amount, and trim to the line.

On a wedge I start by shimming up the ends as before, but then add a couple of shims on the lower bout to tilt things. I find a 1" difference between the bass and treble sides to be enough to be helpful, so that's about what I usually do. That means that the treble side will be 1/2" lower then normal, and the bass side 1/2" taller. A pair of shims that are 1" different in height does the trick. BE SURE YOU MAKE THE TAPER IN THE RIGHT DIRECTION ! One of my friends made up paper patterns, and applied them to the wrong sides, ending up with a set that would make a nice left-handed guitar, if it were not for the cutaway... Knowing how likely I am to repeat that sort of thing, and how unlikely I am to ever make two alike, I just use the shims...

So I will not be doing a wedge on the current guitar because it sounds like it's best to have the opposite side a bit taller and the wedge side the same amount shorter. I've already "trued" both sides to equal widths and their respective 30' and 15' radii. But this is all excellent information for the next one
Hope I didn't hijack your post, Robert!
Alan, as always you've given wonderful detail….thanks!

So a little bit of progress…
The headblock has been shaped and glued in.
Bias tape glued to the sides.
Cut the linings and glued them in.
Started shaping the back braces.

And now the pics...


Aslso made the kerfed lining and installed that.


Goofed up in a couple of plases where didn't match the edges well or split the lining on the curve. Had to pull them off and redo. Also redid the curves of the cutaway as the lining kept breaking due to the short radius. Needed to get in with a trianglular file and open the kerfs a bit more to allow for the bend.



So here's the current state of the sides.


Lastly, started shaping the braces.


So that's where she be!

Looking good, Robert, but those back braces are massive! I'd remove about 60-70% of that brace material.


Ken Jones
Mountain Song Guitars

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Mountain Song Guitars www.mountainsongguitars.com

Don't they look it? I'm thinking my grandson will be able to climb on that with no worries!

We hadn't talked much yet about the tuning process for the back and top but I expect there will be a tad bit of shaving involved.

Lots of that back brace material is going to end up on the floor, particularly from the two lower braces. It's just a lot easier to make them all the same height and take the wood off than it is to wish they were not so small later. I make them wide, in fact, because they tend to end up so low: more or less like the upper braces turned on their sides. Narrow ones just look puny.

Lastest Pics...
Yesterday I spent most of the morning trying to get the sides finished to accept the top/back. Planed down the headblock and tweaked the side to better fit the sanding plates. I suspect i could have quit with the planes and gone sooner to the sanding dish, but now that i've gone through it it seems obvious looking back.
I was surprised at how quickly the sanding part finished things off.

Without further ado...
The sanding dish and just a measly single piece of sandpaper. That one section of paper cleaned up the rim nicley in about 1/2 hour after getting close with the plane.


I'm sure you've all done this but i just want to document as much as i can. This is just a pic of the back side of the lining being sanded down.. Yawn!


This pic starts to give a sense of the box as a whole. I like the way AL put it... I'm 9O% done with 9O% yet to go... Actually in this pic i have just marked wher the braces will be butt into the lining. I have not yet brought those back braces down to their final size.


Lastly... One of the students has a table saw with the blade for cutting the fret slots so i had him do that for me. Just to show how that madagasgar rosewood will look witht the top/rosette.

Now, i did notice that i made a goof by not flipping the fretbaork around so the fat section of the sapwood laytowards the body of the guitar. I think it's going to look out of balance getting thicker toward the headstock. Oh - well. Maybe when it's all shaped it won't look so odd.

Thanks for looking!

Shouldn't they be the other way around? I thought the back always had a smaller radius than the front.

I gotta agree there

Thnks for the correction. I know they were different but didn't pay much attention to which was which. He's got a square dish for the back and a round one for the front and that was about as far as i needed to know to keep them straight.

Or... was it the round one for the back?

It's 15' on the back and 25' on the top.