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I was able to get my little rounded finger plane to work on the figured maple by putting the bevel up. That helped a lot and I was able to get the outside of the back carved to the rough shape. A little work with the scrapers and some sanding finished off the job. Now that the top and back are carved on the outside, the next step will be to work on the inside and get everything to the correct thickness.

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Steve Smith
"Music is what feelings sound like"

Forgive me if this is a daft question as I have never attempted or read up on this kind of build, but wouldn't it have been easier to carve out the inside first whilst the outside was still flat? Then when doing the outside it would still sit flat on the rim of the carved out inside? If you get what I mean?!

Hi Lee - this is my first mando build and I had the same question at first. Being my first, I am following the process I have seen used by others, like Arnt in his mandola thread. One of our experienced mando builders may have a better explanation.

I think the reason is based on the fact that whatever side you carve first determines the shape of the side you carve second. This is because the second side is based on the thickness of the plates indexed off of the first side. In other words, you carve the top to the correct shape, smooth it out so it looks good and then the back is carved based on the required thickness at certain areas on the plate. I think it would be very difficult to get the top shaped correctly and still get the correct plate thicknesses if I had carved the back first.

Edit: I did some checking and Siminoff in his book shows carving the inside first but mentions in the text it can be done either way.

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Steve Smith
"Music is what feelings sound like"

Started roughing out the inside of the plates. The mandrel I used would have worked better with a larger radius on the head. As it is I have some small dents to steam out.

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Steve Smith
"Music is what feelings sound like"

Hi Steve,

Thanks for the reply, and seeing how you drill out the inside with the mandrel and pillar drill it makes perfect sense!

Looking great Steve!
Dan

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wah
Wah-wah-wah-wah
Wah

Thanks Dan. Lots of dents from the mandrel but I was able to steam them out.

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Steve Smith
"Music is what feelings sound like"

It's coming nicely, Steve. Regarding the dents: I did the same thing, too, when I drilled out the inside of my archtop guitar back. I padded the top of my dowel with a couple of layers of leather before drilling the top, and that worked a lot better--virtually dent free.

Hi Patrick and thanks. Fortunately I was able to steam out all of the dents but I like your idea of a piece of leather and will use that next time.

BTW, the oil fill/color project is still alive and well. I've got a satisfactory test piece and will get back to that one soon.

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Steve Smith
"Music is what feelings sound like"

I made a carving support out of some foam insulation I had laying around. It works surprisingly well.


That maple is hard so I used a mallet and gouge to rough out the inside of the back.


The inside of the spruce top was much easier, I didn't need the mallet.


Next step will be to graduate the plates to their final thicknesses. I also started the neck today but no photos of that.

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Steve Smith
"Music is what feelings sound like"

You really have the chips flying, that will be strung up in a week or two. You have to bring it to the meeting in a couple of weeks. Looks great.

Don't know about a couple of weeks but I'll bring what I have to the next meeting.

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Steve Smith
"Music is what feelings sound like"

I've been working on graduating the back. Got the bulk of the waste off using a convex palm plane with a toothed blade, getting down to the last 50 thou or so and it's going slower as I figure out how to get this done efficiently.

Also got the neck roughed and darned if I didn't glue the ears on before I routed the truss rod slot. Oh well, just makes what should be easy a bit less easy

Also found out I'm out of ebony scrap for the head and back plates so I ordered some ebony shorts from West Penn.

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Steve Smith
"Music is what feelings sound like"

Hey Steve, if you plan on using a table mounted router and fence for the truss rod slot, just tack a filler strip the same width as the ears to the neck, and route away!

Alex

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

Hi Alex. I'll probably use a laminate trimmer but basically what you said. Just annoyed that I didn't do it before I put the ears on:)

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Steve Smith
"Music is what feelings sound like"

That's looking pretty good there!

Thanks Hans. I finished graduating the back with a scraper. It was a treat to hear the tap change from thud to musical as I started approaching the graduation numbers you gave me. Any reason to do anything further to the inside of the back, i.e. sanding? I had thought I would leave it as it is from the scraper.

Top is almost finished too. I have to agree with Arnt, I like carving plates.

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Steve Smith
"Music is what feelings sound like"

Steve, I would refine it more, and looks like you have a hump all the way around. I would also refine it right to the line of the kerfing. I have never had a problem with sanding it. I used to get it down to 400 grit and steel wool.

Thanks Hans, I will keep at it

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Steve Smith
"Music is what feelings sound like"

Having never done this before I was a bit nervous about how far to go with the work on the inside but with a little push from Hans I went back and did some more work based on his advice.

Here is the inside of the back, hopefully in it's finished state


And the outside of the back. You can easily see the mirror of the shape from side to side.

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Steve Smith
"Music is what feelings sound like"

The back looks good. Thank you for posting I am going to try late this year to build one as well. Seeing you go through it sure helps. I know anytime I am removing material I always am leaving to much on. My necks end up a bit thick, the nut slots not low enough, on and on.

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http://www.Harvestmoonguitars.com

That looks a lot better Steve, but looks like you still have a hump all the way around. I can't find a photo of the inside back of one of mine, but did find a photo of the top on the ribs and completed. You can see the smooth transition from center to edge.



I'll keep looking for photos of contours. Another problem I see is that you have contoured the very front of the back where it should be very thick. Probably OK structurally, but Gibsons were straight line from peak of back to heel button on the outside. They were very thick in the very front area at the center.
Here is a thread from a few years back with some photos of an A4 of mine...

http://www.mandolincafe.com/forum/showt ... t=brentrup

John, thanks - it's turning out to be a fun project and I'm learning a lot as I go.

Hans, thanks for the link. I see what you mean in the photos. I contoured the outside of the plates using Siminoff's plans - I just copied them and glued them onto the plates. I'll mark my plans so the higher spot flows more toward the neck as in your photo. The wood is still pretty thick over the neck block, about 6mm. The binding ledge is higher, per Siminoff, over the neck block than around the rest of the back.

The hump on the inside is a reflection of what turned out to be a bit more of a recurve than planned just in from the outside edge. The hump is probably a bit less than 1mm off of flat. I will double check the recurve area and make sure it is right around 2.2mm, I may still be a bit thick there.

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Steve Smith
"Music is what feelings sound like"

Think you have the idea Steve. The hardest area to carve is the transition from convex to concave.

Thank you Hans for the advice!!

I went back and remeasured and sure enough the 2.2mm band was very narrow and did not extend very far up toward the neck end. So I reworked it once again and the top is much more alive feeling - tapping anywhere near the rim creates a sustaining kind of vibration (what I look for in guitar tops) whereas before there were only a few selected spots that would cause that. I sure hope that's a good thing. So now the thinned area is much closer to the rim and the hump is pretty much gone.


In other news my box of mixed 4/4 Ebony shorts came in from West Penn.


Some of it is really nice and black. I cleaned up one stick and sliced in down the middle so I can use it for the headplate.


Got it glued up so should be able to clean it up and resaw it tomorrow.

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Steve Smith
"Music is what feelings sound like"