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The Mould and Garland


Tim McTigue

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So now that I had a half-template, I was ready to make the mould and proceed. Oh, if only things went right the first time, eh? I guess they would, if I were working carefully and paying attention. However, the first mould I made from that aluminum template (that I had spent quite a bit of time preparing), knocked me down a peg or two. I spent an evening carefully marking out the mould and cutting it out, and the blocks, and getting everything all ready, THEN decided to take some measurements to make sure I wasn't going to regret anything later. Good thing I did! Turns out, my mould (and outline template) was about 3mm TOO SHORT! Which, of course, flattened the entire lower bout section, and made it look really ugly. Well, scrap mould #2. I have NO idea how this ended happened, but I ended up cutting an "extension" lower-bout piece to place under the half-template, to give the lower half the correct outline when I traced around it. I just wasn't going to take the time and effort to make another aluminum template - save that for violin #2. This approach ended up working pretty well, and below are three views of the mould and garland that resulted.

Speaking of the garland, here's how that went: Since I don't own a thickness sander, I opted for the thicknessing method recommended by Michael Darnton - by this time I had done a very serious amount of lurking and reading here at Maestronet. Since the wood I had chosen was pretty well-flamed, I knew I was going to need a notched plane, and since I was on a tight budget, I grabbed a very old and very cheap block plane I had laying around, took the blade out of it, and took my Dremel cutoff wheel to it. After sharpening the blade, of course. I really wasn't sure it was going to work, but lo and behold, it did! In fact, it worked a treat.

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For my thicknessing board, I took a piece of fiberboard shelving I had laying around, and made 2 strips of aluminum about an inch wide and ~1mm thick, and glued the strips to the shelf, about as far apart as the width of the rib stock. I clamped this board to my workbench, then clamped a rib between the alum. strips, and this allowed me to plane the ribs to thickness. I would plane one side until it was almost down to the alum. guides (and of course swap it end-to-end to do the clamped end), then turn it over and plane it down to the strips. It's really not possible to get it completely down to the strips, esp. with the notched plane, so there's still lots of wood to get rid of with the scraper. And since this was my first time, I was reticent enough that I even left way too much thickness with the plane, and spent WAY too much time scraping. One thing I also discovered, is that when using that plane for a couple of hours, it's REALLY easy to give yourself a repetitive strain injury. At one point, after working on the ribs for a few days (in the evenings), I had to take an extended break because I was starting to lose feeling (semi-permanently) in my right hand. It took a couple weeks to get back to normal. Scary! Anyway, after the planing, came the scraping. Here's how you know if your scraper is sharp:

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And of course, I also discovered that if you scrape with the scraper perpendicular to the rib, you get a really wavy rib when the wood has a nice flame. Once again, MN came to the rescue - you need to hold the scraper at an angle if you want a nice smooth surface:

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Of course, in true McTigue form, I ended up breaking two of the rib pieces while planing/scraping (for instance, there was the time I was scraping a piece, and I made a scraping stroke away from me, then went to lift the scraper and return for another stroke, but didn't lift it high enough... caught the scraper on the end of the rib as I lifted, and... SNAP! - 3 pieces where there used to be one!). I did end up with enough left over, but it made my cutting choices REALLY critical, and I had NO wood to waste in learning to bend...

Once I had the mould made, and the ribs planed and scraped to thickness, the next problem was of course to bend the ribs and glue them to the mould. I didn't have a bending iron, and couldn't afford one, so once again MN came to my rescue, and I read about a technique for bending the ribs on wooden forms, using a common clothes iron. I decided to try that, since I had an old iron at hand, and didn't mind taking the time and effort to make the forms:

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I ended up cutting some narrow strips out of the broken waste wood once I had the rib pieces cut, and I used this to practice. Good thing I did, because this technique does take some getting used to. You have to soak the wood for a few minutes to get it wet, so that it will bend nicely. Then, when bending, you have to press fairly hard, and move not TOO slow, but not too fast, either, and it takes some familiarity and confidence to do it right. I ended up bending about a dozen small test pieces before I could trust myself not to break the actual ribs. And, in the end, I managed to bend them all without breaking any:

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