catnip Posted February 12 Report Share Posted February 12 1 hour ago, plasterercaster said: On a more practical note, you don't seem to have any holes for clamping the c ribs, That is because the classical method used a different way to glue the C bouts. They used a wooden dowel with a caul wrapped or tightened with a cord using a very neat "boy scout" knot... not usually shown in violin making books. Quote Link to post Share on other sites
plasterercaster Posted February 12 Report Share Posted February 12 23 minutes ago, catnip said: That is because the classical method used a different way to glue the C bouts. They used a wooden dowel with a caul wrapped or tightened with a cord using a very neat "boy scout" knot... not usually shown in violin making books. I know, there are holes for the dowels on classical molds Quote Link to post Share on other sites
catnip Posted February 12 Report Share Posted February 12 Here is an example Quote Link to post Share on other sites
plasterercaster Posted February 12 Report Share Posted February 12 44 minutes ago, catnip said: Here is an example very nice, but I think you are using the "wrong" holes to glue the c bout ribs. What do you use the holes above and below the corner blocks for? Quote Link to post Share on other sites
MikeC Posted February 12 Report Share Posted February 12 I suppose you could use either holes for the C bouts. The holes in Catnip's picture I use for the upper / lower bouts. Quote Link to post Share on other sites
David Beard Posted February 13 Report Share Posted February 13 Except they didn't use dowels to clamp, but carved well fitted counter forms in a style just as distinct and meaningful as the molds. Quote Link to post Share on other sites
CaseyLouque Posted February 19 Author Report Share Posted February 19 4th mold I finally have something that’s more correct but not very pretty. Thought I’d post my first two molds for a good cringe / laugh. “Some people show you how to do it. Some people show you how not to do it.” Maybe on the next ones I’ll make them look pretty as well. But for now I’ll be on to the next miss adventure. I’ve at least found three ways not to make a mold. If you have more advice on the molds I’d be happy to hear and feel free to comment.This won’t be my last mold by a long shot. But For now some rib stock is calling my name. Quote Link to post Share on other sites
uncle duke Posted February 19 Report Share Posted February 19 7 hours ago, CaseyLouque said: trace around this one, flip it over and trace again to see how everything lines up. Quote Link to post Share on other sites
Davide Sora Posted February 19 Report Share Posted February 19 10 hours ago, CaseyLouque said: If you have more advice on the molds I’d be happy to hear and feel free to comment.This won’t be my last mold by a long shot. Is this an artifact of the photo or are the lower part of block recesses not 90° with the centerline? If so this could give you problems when you have to separate the ribs from the form. Quote Link to post Share on other sites
CaseyLouque Posted February 19 Author Report Share Posted February 19 4 hours ago, Davide Sora said: Is this an artifact of the photo or are the lower part of block recesses not 90° with the centerline? If so this could give you problems when you have to separate the ribs from the form. Seems that you are correct i Reviewed the SVG i used to make the mold as well . Seems that the corner blocks are extended beyond 90 Degrees and to copensate i squared them off and dug it in made it no longer square to the center line. figure 1. Shows block squared. Figure 2 where it should be based on the second box. Figure 3 shows my original drawing has a 95 degree angle. So should i correct the mold and drawing to match the box in figure 3 and decrease the angle from 95 to 90? Or leave it at 95degrees? Quote Link to post Share on other sites
David Beard Posted February 19 Report Share Posted February 19 1 hour ago, CaseyLouque said: Seems that you are correct i Reviewed the SVG i used to make the mold as well . Seems that the corner blocks are extended beyond 90 Degrees and to copensate i squared them off and dug it in made it no longer square to the center line. figure 1. Shows block squared. Figure 2 where it should be based on the second box. Figure 3 shows my original drawing has a 95 degree angle. So should i correct the mold and drawing to match the box in figure 3 and decrease the angle from 95 to 90? Or leave it at 95degrees? The notches are not meant to be square. The obtuse shapes helps when it comes time to detach the blocks. This also applies to both end block cutouts. The sides of those notches are meant to be obtuse. AND, the bottoms of those notches aren't supposed to be unbroken. Drill a few holes straddling those lines before cutting them. This way you have a few pry points when its time to separate the blocks from the molds. The horizontal lines etched on the classical molds connecting between corner notches are also not random or pointless. These help guide you in restoring worn notches later on, in working the corner blocks, and they document the radii for the mold's outer corner circles. Quote Link to post Share on other sites
CaseyLouque Posted February 20 Author Report Share Posted February 20 Thanks for the clarification. @Uncle Duke I did trace and check and everything lines up mold is symmetrical. now I'm off to fix the corners. Quote Link to post Share on other sites
Davide Sora Posted February 20 Report Share Posted February 20 12 hours ago, CaseyLouque said: Seems that you are correct i Reviewed the SVG i used to make the mold as well . Seems that the corner blocks are extended beyond 90 Degrees and to copensate i squared them off and dug it in made it no longer square to the center line. figure 1. Shows block squared. Figure 2 where it should be based on the second box. Figure 3 shows my original drawing has a 95 degree angle. So should i correct the mold and drawing to match the box in figure 3 and decrease the angle from 95 to 90? Or leave it at 95degrees? Drawing 3 is correct, I would adjust the block recesses on the form by bringing it back as on the drawing. To do this I would glue new pieces of wood to the form so as not to widen the block recesses too much, respecting the heights (distance between the two horizontal lines) which are important to determine the point where the curves change from convex to concave on the outline, and the curve of the block itself. (see David Beard previous post). Quote Link to post Share on other sites
CaseyLouque Posted February 27 Author Report Share Posted February 27 Glued in some slivers of wood cut and filed them. I pasted the bottom half of template onto mold. traced mold on paper to draw and plan corners for mold. They now lineup. Wanted to draw up corners based off this mold if something looks incorrect please comment. I plan to eventually make metal corners based off the finalized drawing. Quote Link to post Share on other sites
Davide Sora Posted February 27 Report Share Posted February 27 6 hours ago, CaseyLouque said: Wanted to draw up corners based off this mold if something looks incorrect please comment. I plan to eventually make metal corners based off the finalized drawing. Your corners seem a bit too long and skinny to me, there is also some disproportion between the size of the upper and lower corner blocks. The height of the upper block (distance between the two parallel lines on the original G form) should be 25.5 mm and the height of the lower block 24.5 mm Quote Link to post Share on other sites
CaseyLouque Posted February 27 Author Report Share Posted February 27 9 hours ago, Davide Sora said: Your corners seem a bit too long and skinny to me, there is also some disproportion between the size of the upper and lower corner blocks. The height of the upper block (distance between the two parallel lines on the original G form) should be 25.5 mm and the height of the lower block 24.5 mm Shortened and made some corrections. Found out my kitchen table isn’t level so moved to my glass drawing desk. They were indeed to long. I took some measurements and included in corrected drawing. Took picture with better device. unfortunately I seem to have gotten corn dog grease while helping with the 4yr old. “C’est la vie” Hopefully this looks better thanks for looking and posting. Quote Link to post Share on other sites
DarylG Posted February 27 Report Share Posted February 27 Personally, I always start with a drawing of the finished outline I want to achieve, then I make the templates and molds from that drawing. Quote Link to post Share on other sites
Davide Sora Posted February 28 Report Share Posted February 28 15 hours ago, CaseyLouque said: Shortened and made some corrections. Found out my kitchen table isn’t level so moved to my glass drawing desk. They were indeed to long. I took some measurements and included in corrected drawing. Took picture with better device. unfortunately I seem to have gotten corn dog grease while helping with the 4yr old. “C’est la vie” Hopefully this looks better thanks for looking and posting. Better, but the top corner is still too sloping down. It seems to me that the edge overhang from the ribs you are using is also too narrow, which still makes your plate corners look skinny. Of course, these are only aesthetic factors and we could discuss them indefinitely without coming to conclusive things because they depend on personal taste, there is no absolute good or bad. So I only speak for myself, in the drawing below I show you a sketch I made to set my corners so you can visually realize what I mean, which is better than any description in words. Also, you may not like my corners, so you are free to make yours however you like. Moreover, these are only indicative sketches that I made just to get an idea, then what will come out in the real violin is always slightly different (a bit longer or shorter, wider or narrower, more curved or flatter, and so on). In fact, even the top corner I drew is still a bit long and too protruding, and the lower one a bit too short,drawings are only preparatory and never definitive. Something to keep in mind is that in the drawings you always have to deal with the pencil trait which is deceptive to the perception, instead of in the real work where you have to deal with sharp edges of wood without the thickness of the pencil trait. It's different. Quote Link to post Share on other sites
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