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First Acoustic. Not exactly a guitar...


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2 hours ago, mattharris75 said:

The top is inching ever closer. I can tell it's going to be beautiful when done, but this redwood, with its fuzziness, softness, and unpredictability... Well, it's not so much fun to carve. The plus side, I suppose, is that the carving goes much faster.

Yeah. How is its resonance?

SR

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Ehh, sounds like wood to me. :)

Looks like someone dissected an instrument on my work bench...

20170524_234247.thumb.jpg.19002309b45131acfa792c0e99dc41fe.jpg

 

The top is getting pretty close now. Still have some work to do in a few spots, but it's getting closer. Using a scraper on the redwood isn't so bad, compared to a chisel, but you do have to be super conscious of the grain direction.

I also ordered some Transtint Brown Mahogany dye to play with. So, I'll be experimenting with that this weekend, along with dark vintage maple and honey amber as burst colors.

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Just for fun:

20170527_162034.thumb.jpg.171b08385cdcc03e06c99cb67b21b098.jpg

 

I've done quite a bit of work on the top. It's close...

I've also been working on a test finish. I wish I had a larger piece of redwood to play with, it's tough to get an idea of the full effect with such a small piece. The colors on these pieces are Brown Mahogany, Dark Vintage Maple, and Honey Amber. I'm afraid the Honey Amber may have pushed everything a bit too yellow. It's tough to tell with the cherry, as it will continue to darken over the next few weeks. I also sanded off the awful baking soda mistake, which left some muddiness in the pores.

This is garnet shellac, transtint dyes mixed in water, two spray coats of clear shellac, and a couple of coats of Tru Oil.

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It certainly has a vintage look, but I'm not sure it's quite the direction I want to go.

 

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Making shavings...

20170529_165917.thumb.jpg.3c96d94df3edd8c4d1562e3187558169.jpg

 

So, after carving the recurve into the top I had to go back and do the same to the back. Man, the cherry is so easy and consistent compared to the redwood. 

I think I'm going to order some transtint red mahogany and ditch the honey amber. The Tru Oil by itself takes the wood far enough in the yellow/orange direction. I may dilute the dark vintage maple, which has a bit more of a brown tone to it, to use as the center color of the burst, and then the red and brown mahogany on the edges. We'll see how it goes. Lots of trial and error here.

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17 hours ago, mattharris75 said:

Making shavings...

20170529_165917.thumb.jpg.3c96d94df3edd8c4d1562e3187558169.jpg

 

So, after carving the recurve into the top I had to go back and do the same to the back. Man, the cherry is so easy and consistent compared to the redwood. 

I think I'm going to order some transtint red mahogany and ditch the honey amber. The Tru Oil by itself takes the wood far enough in the yellow/orange direction. I may dilute the dark vintage maple, which has a bit more of a brown tone to it, to use as the center color of the burst, and then the red and brown mahogany on the edges. We'll see how it goes. Lots of trial and error here.

I do like a cabinet scraper. Nice work

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Me too, Norris. Working with scrapers is great.

Not much progress in the last few days, a little time here and there continuing to refine the top and bottom plates before I cut/carve the insides of them.

I made this little jig for my drill press to help me hog out the material to the appropriate thicknesses:

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I'm also working on replacing my shop lighting. I ditched the old fluorescent fixture for an LED fixture, and am adding a second one out over the main shop area. Should finish that up tonight. It will be nice not to have to wear my headlamp all the time. :)

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I am totally stealing that idea for the drill press thickness jig- I was just about to start looking for ideas for the top of my veillette copy so perfect timing. thank you for sharing.

also- I must have missed your May 27th post but that mock up really looks great Matt.

I am still coming over to your house and throwing some saw dust around and mess things up a bit. You need to come to the dark side and join us slobs.

 

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Thanks! I think it's shaping up well.

So I figured out one thing that I won't be doing again. Using .020 binding as the outside most piece of binding. Too easy to sand through. I haven't...Yet. But I definitely sanded off about half of it on one side of the neck while finishing up some rough shaping. Going to have to be careful.

So, finishing experimentation. After a few weeks the cherry back under the garnet shellac darkened up enough to look muddy. So this time around I went with a lighter orange shellac seal coat. And this time I used dark vintage maple, red mahogany, and brown mahogany to shade the cherry. I like this much better! Also has a couple of coats of Tru Oil on it. Should have a nice shading effect without looking like a traditional burst. 

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Also, 8000 lumens of LED light has totally revolutionized my shop! No more headlamp for me!

 

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With fear and trepidation I began carving out the inside of the soundboard this weekend. 

I decided on some base numbers for my profile based on reading, asking luthiers questions, and some total guess work. I used my drill press jig to cut holes at those various depths around the top, and then spent a couple of hours with a gouge and finger plane getting it to where it is. It's maybe halfway done at this point, not including the fine tuning, but I'm definitely getting more comfortable with the process as I go, and it's starting to go a little faster. The reason that there are large uncarved sections in the middle is that I want to manually carve a slight hump that runs the length of the top along the string line in order to provide a little extra structure.

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So far, so good...

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Thanks Scott!

I spent a little time tuning the top last night. It's right at 4mm in the recurve and 6.5mm at the thickest part of the top.

I was at 7mm initially before one of the luthiers I consulted said to take it down another .5mm in the middle, and it's really interesting to hear how dramatic a difference that .5mm and 8 grams of total weight can make:

The top @ 7:

Harris 6 - Mandola - Top Tap 1 - 222g.mp3

A high tap tone. It's tight, there's not a lot going on.

The top @ 6.5:

Harris 6 - Mandola - Top Tap 2 - 214g.mp3

A lower tap tone. Much more resonant, more bell and drum-like.

I will also tune, trying to make sure there are no dead spots, after the tone bars are attached and the F holes are cut.

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So, the tone bars are fit. And man, that was a much bigger pain than I expected. In the end I managed to get it quite close, not 100%, but very close... I tried using chalk to mark the high spots and it didn't work. So I tried carbon paper, and it was marginally better, but I didn't seem to be making much progress. I ended up holding them in place and sliding strips of sandpaper under them over and over and over and over... 

Next up, cutting the F holes and then gluing in and carving the tone bars.

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7 hours ago, mattharris75 said:

I ended up holding them in place and sliding strips of sandpaper under them over and over and over and over... 

I put the paper in place on the top and rubbed the bars back and forth over them, about a half inch sweep forward and back, and then finished the same way you did. 

It takes a minute all right.

SR

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listening to you two it makes me appreciate that Ribbecke jig all the more. I am thinking about carving out and " leaving behind " tone bars (tone bars made of the top wood and not glued) on the Veillette copy I am doing. I havent thought it all the way thru though. I need to put it to paper and make sure I can work it with my tools/hands and fit in the spaces.

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Scott, when I was roughing out the fit I was able to slide them back and forth a bit, but once I got close they really wouldn't move, due to the shape of the top they pretty well locked in place. But yeah, using chalk/carbon paper and a scraper was an exercise in futility for me. Just a lack of skill on my part I suppose.

So, integrated tone bars have been done, but they don't generally appear to be highly thought of in the mandolin or violin worlds. Presumably something to do with the grain direction of the bars vs integrated ones having a lot of run out because of the angles. Another one of those areas where I have a hard time finding concrete answers, and tradition reigns. 

Another one of those fuzzy tone voo doo areas is how the tone bars are positioned. You can see that the treble bar is closer to the center line than the bass bar. Why? At the end of the day I really don't know. Some people will give you their ideas, but ultimately it's because Lloyd Loar did it that way back in the 1920's. Archtop guitars often use symmetrical tone bars, and I nearly did that, but ultimately decided to stick with mandolin tradition.

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45 minutes ago, mattharris75 said:

So, integrated tone bars have been done, but they don't generally appear to be highly thought of in the mandolin or violin worlds. Presumably something to do with the grain direction of the bars vs integrated ones having a lot of run out because of the angles. Another one of those areas where I have a hard time finding concrete answers, and tradition reigns. 

Another one of those fuzzy tone voo doo areas is how the tone bars are positioned. 

Matt- originally I wasnt even going to shape the inside of the top- since this is an electric instrument I am building- but then- I thought- well- why not- so- I want the structure there- but I dont want the hassle of fitting separate tone bars- the area under the bridge will be solid on mine- but if I was building an acoustic instrument- I wouldnt even entertain the idea of integrated tone bars- not sure why- but would lean towards tradition on an acoustic instrument.

I must first decide 100% on "f" holes-if I decide on F holes-  then I will shape the inside for sure- if not- it will probably stay solid. 

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Yeah, on an electric it won't really matter either way. If you were to do F holes you could always just thin the area around the F holes and leave a thicker section down the middle. Even carved top mandolins are thicker 'along the string line', as they call it, for the sake of extra structure.

 

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And that may well have been Lloyd Loar's thinking as well. I'm not sure anybody really knows. I think the science of the matter indicates that it's really a whole lot more complex than that. It's just one component in a complex system.

In my research most mandolin luthiers seemed honest in saying that they placed them, at least initially, based on Loar's specs, and it works. And since people want to buy mandolins that sound like his, well, that's where the market is. So, pragmatism rules the day.

Even guys that have experimented with tone bar placement don't seem to be able to articulate any particular quantifiable difference. So, I tried not to overthink it...

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F holes cut.

The treble F hole has been cleaned up, the bass F hole still needs some work, I just ran out of time last night.

I got to use my fathers day gift, a new scroll saw, so that was fun.

Overall it went smoothly, but this redwood is incredibly splintery. There are a few very small areas of chip out, actually due to sanding, not the saw. It doesn't take much with this wood. It will get fixed in final sanding, but the more I work with redwood the less I like it...

I'll clean up the other F hole and possibly get the first tone bar glued up tonight.

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