Saturday, February 21, 2015

Cello Cross Arch Design

I've been avoiding the basement; it's just too cold down there right now. So I planned out my arching. I did have it somewhat figured out. I knew my long arch, and I knew how the inside long arch would go. I roughed out the inside catenary, leaving it some ways in from the edge, so I could always widen it up if I needed to. Now I needed to see where I need to be.

I drew out the f holes on the inside of the belly. This way I can see how the f hole sits on the arch.



The area of the lower wing looks like it should work into a nice shape. I make that area outside of the f holes as their own shape. It fits into the rest, and starts as a continuation from above the f hole; but it terminates as it flows into the lower wing by the eye. The arch below the eye sweeps into the edge in a big curve. At least that is the way I do it. That's what I like. I don't know if it is anyones style, but it makes sense to me, and it works well with my method of making. This is how it looks on the viola. First the upper arch flowing into the lower wing.


And this is the treatment at the bottome end:


It's nice and sunny today. Everything is SOOOO much better when it is nice ans sunny. I drew up some archings the other day at work. It's really easy to do. I had the measurements of the width and height, and just went form there. I started 40 mm up from each block, and made them 30 mm apart. I ended up with 21 of them. The most interesting ones are the middle ones.


I stay quite a ways away from the edge. If you get too close to the edge, your arching will be more bolbous looking. I'm not trying to get that. I want it looking right. You can see how the catenary defines the center portion of the arch, but the recurve is a differnt thing altogether. It seems to me the recurve is where the aching templates would be the most useful.

5 comments:

  1. Basement temp- which is it: 35-45, 40-50, 45-60?

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  2. One thermometer reads 36, the other 42. It's been -20 a few mornings, and never above freezing. Our normal high should be 34 or so. Our water pump went out Friday night, they will fix it on Monday. Luckily the water is high in the sump, so getting water to flush toilets is easy enough, and the heat and electricity still work.

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    1. You'd think with all that good space in your shop there would be decent heat for you. Is that a split level home with the garage on the other side of the cold wall or a full basement? Kind of tough to see what was done insulation wise with all the walls being sheetrocked. Even little gaps and voids can make it miserable in the basement.

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  3. It is a full basement, so I could probably get some kind of space heater to turn on while I am down there. The windows let in the most cold I think. I didn't put the plastic film on this year. Just forgot. I really don't like cold. Just thinking about cold (well, practically just thinking about it) turns my fingers yellow. Something like Raynauds syndrome or something like that. Yeah, I really don't like cold. I can take heat all day long. I can sweat all day, it won't bother me. I don't like to shiver for a minute. Arizona?

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    Replies
    1. I've been thinking Los Angeles.

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