Progress so far plus edge thickness question.

[Crimson0087]

I haven't posted on a while. The back is going very well I'm very happy with my arching. I used davide's method of using a contour gauge...much better than arch templates. Anyways I've got my edges down to 5mm I know that's too thick but can anyone suggest a range like a minimum to max for the edge...I'm nervous about going too thin afraid I'll break something. Anyways here's the back. Still have to file the outside so it's not the final shape but close....I kept it unfiled whole I gouged it to protect edge. Also in bringing down the edge from say 5mm to 4 should I use scrapers or keep at it with finger planes...would a flat bottom plane be beneficial at this point or keep using curved?

 

 

[David Rosales]

In the Derber method, the edge thickness is done in stages. The method is to first gouge and plane to 4.7mm, then repeated to 4.4 mm, and repeated again to 4.1 or 4.2mm and finished to the final thickness of 4 mm in the back and 4.2 mm in the top with a 0-cut hand file. He notes that these dimensions are on the thick end for the first instrument built to allow for correcting mistakes in the future, if necessary. 

[jacobsaunders]

At school I was taught to make the edges 3,5mm top & bottom bouts, 4mm in the middle, and the corners 4,5mm, with the button counting as a corner. I have always done it with a cutting gauge and a chisel. You need to finish the outline first

[Don Noon]

I didn't go to violinmaking school and wasn't taught anything, but I work exactly as Jacob says.

[Rico Suave]

Imma link this topic in the  "Self-taught violin makers; seconde parte" thread...

I think Nervous Novices tend to lean towards thicker edges (and corners ), for the reason stated in the OP; "I'm nervous about going too thin afraid I'll break something. "

 

[Nick Allen]

I do 3.8 for the upper and lower bouts, 4 for the c bouts, and 4.5 for the corners, including the button.

[Davide Sora]

20 hours ago, Crimson0087 said:

I haven't posted on a while. The back is going very well I'm very happy with my arching. I used davide's method of using a contour gauge...much better than arch templates. Anyways I've got my edges down to 5mm I know that's too thick but can anyone suggest a range like a minimum to max for the edge...I'm nervous about going too thin afraid I'll break something. Anyways here's the back. Still have to file the outside so it's not the final shape but close....I kept it unfiled whole I gouged it to protect edge. Also in bringing down the edge from say 5mm to 4 should I use scrapers or keep at it with finger planes...would a flat bottom plane be beneficial at this point or keep using curved?

The thickness of the edge at this stage is linked to the method of carrying out the subsequent workings. If you cut the channel very close to the outer edge like I do, when you round the edges you will enter the channel and the height will go down due to the slope, so you'll need to start with a thicker edge. If instead you cut the channel inwards by a couple of mm, exactly where you want the highest point of the edge to be, you won't need this extra thickness, provided you are skilled enough to strictly respect that point when cutting the channel and when you round the edges.

I think the only accurate way to get these measurements under control is to take note of the initial thickness and see if and how much it goes down in the finished violin, so as to be able to adjust the measurements according to our way of working.

Or more simply test the entire work sequence (channel and rounding) using maple and spruce strips of the thickness of our initial edge, and evaluate the possible variations in the measurements induced by the various work systems and different starting thicknesses

[jezzupe]

One can use a piece of scrap that is big enough to practice a mock up "pretend edge". I would suggest cut some type of shallow curve in the board to mimic some part of the body. Basically with this your not to concerned about blending the arching into the recurve, more just cutting the flat table that will establish the edge where the purfling, recurve channel and the eventual round over of the edges that will make "the edge of an instrument"  you will need to do some blending of the "arch" but just enough to work a 6" edge or so . Again simply using a well shaped student instrument as a guide as suggested by Jacob will let you know, "does my edge look like that edge.?"

I just can't stress the importance of using mock ups in conjunction with your actual work to slowly get where you want to be with your first build{s}

For example, if you follow Jacobs advice {which you should} you will be able to use you cheap well shaped cheapo as your practice ground for installing sound post's. This is something that I highly suggest you get comfortable with on something that does not matter, and that you do over and over again, you should set, knock out and do it again like at least 50 times before you try on your violin you built.

when it come time to varnish, do it on scrap first, and on and on with all the things "you don't know how to do or have never done before"

because really there's nothing worse then climbing 3/4 of the hill only to make a fatal mistake and then fall all the way back down and have to start over.

many of the things we do are muscle memory, tool technique specific acts of physicality that require "doing it" over and over for it to feel "natural" , best to practice on things that don't matter before you play the game of "operation"