Joe Swenson

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Everything posted by Joe Swenson

  1. I hear they used to call the MacDOnald Viola. the "Big Mac" ....
  2. Thanks for the detailed info! I'm going with Bruce's numbers which seem to be consistent with the photos when accounting for the distortion.
  3. Cozio Archinto photos must be distorted slightly. I gett 36 mm for the Cozio photos of the Archinto and 40.2 mm for the Macdonald. If I scale the Archinto number, 36 mm down to Bruce's 34.5 mm, then the Macdonald number is 38.5 mm. So its consistent...
  4. Thanks Bruce! It was clear side by side, the MacDonald has taller ribs. I Have the Ashmolean Stradivarius book and measuring there I can get a similar numbers to yours, on the Archinto. I need to go back to my drawing program now and see if I can understand the Archinto and MacDonald measurements in relation to the photos which are from Cosio Archives. Cheers, Joe
  5. Does anyone know the rib height on the MacDonald viola? Putting it beside the Archinto, it looks like the ribs are taller. From my drawing program I estimate the Archinto rib height (lower bout) is about 36 mm, and the MacDonald about 40 mm. Any data available is appreciate. Obviously I'm starting a viola based on the Macdonald. Thanks! Joe
  6. Before shaping the remainder of the neck. I want to get the peg holes reamed out. I found that using the drill press as a guide for doing the bulk of reaming makes the final result quite reliable. I've been using this ever since the first attempt not realizing how much a reamer can wander as the peg hole enlarges.
  7. Continuing on... Something which isn't part of the usual cello build...I bought this gorgeous round cello fingerboard (slightly damaged - small inconsequential chip which I glued back in place) at the VSA convention in 2015(?). Some of the blackest ebony I've seen... After having it in the workshop for a couple of years and went to use it I found it had warped - twisted slightly. Since this fingerboard was already close to the proper thickness I couldn't just plane it flat again or there would not be enough thickness for a properly proportioned neck. So using a heat gun and some proper twisting torque on the fingerboard I got it straightened out. It actually took three heating sessions, the second one closer to the end of the fingerboard, and a third at the wide end to remove all of the twist... Once straightened again, the underside of the fingerboard was sanded and scraped flat. Good to go again, flat on the maple neck gluing surface. You can see the twist angle in the 1x2... Applying heat with foil to distribute the heat and torque on the 1x2 the twist is corrected. Still some twit at the end so the process is repeated. Little more complicated on the wide end. Uneven clamping with a spacer on one side puts the needed torque. Pretty near flat and with a little sanding and scraping its flat again.
  8. If a porous surface is good at absorption then it would be poor at producing coherent sound as well. The the question is how much do the ribs contribute to the sound? I played the cello once without the end pin, between the calves of my legs at it was clear the overall sound of the instrument was reduced. Which says to me freestanding ribs have a non negligible contribution to the sound of instrument. This confirmed what I felt was a good reason for leaving off the linen squares, that many recommend to be applied to the inside of the ribs. But that's for another discussion... So I cleaned up the rib - both sides. Definitely the better choice. Finally learned how to properly sharpen a scraper. Lol... Making nice curls of scrapings.
  9. Once again... Thank you! Makes sense that the depth of the defect would be key here. Don't want a point of failure down the road. Cheers!
  10. Starting cello #2 and thinning the ribs. The rough cut ribs have little dings in the wood. Easy to clean up one side when thinning. I tend to just work from one side when thinning and leave the other side alone relegating it to inside the cello to exist unseen. Any reason not to do this?
  11. It's always about me learning to do things better. Not worried about the time it takes me to do a repair. Expense yes... but I'm retired now and working for myself so my time is "free". I just sold a similar vintage Stainer with a much less flamed 2-piece back at my wife's antique store last week and they're coming back for another one next week. I have a similar vintage Czeck Vuillaume copy ready for them. Paid $35 for at a flea market. Regraduated the top. It's quite nice now. A Mariachi band apparently is looking for instuments. I like the idea of reaming out the hole and filling it. Not sure the peg reamer has a big enough diameter. The varnish is so dark you can't see any flaming in the area so it should be fairly easy to blend in a piece of plain maple. BTW.. The flames are real. Really nice!. ... its nice wood. Fixing the button will be more of a chore separating the back. Will give it a go anyway. Some student will love this instrument. Thanks all for the feedback! Cheers, Joe
  12. Wife found this lovely Jacob Stainer copy - made in Czeckoslovakia (c.1920's) at an antique shop in the valley on the weekend. She texted me the photos and saw the neck might need to be reglued but everything else looked good. SO the $20 price tag seemed a steal. When she got it home I saw the neck was more than just a reglue job. Root cause is a broken button. Also a small crack in the top which was separated from the ribs. But all the corners are in tact and the reest of the body is solid. The Maple is beautiful! Nice highly flamed single piece back! This is the second single piece back violin I bought with a broken button. I'm already familiar with button repair. Is this a problem with single piece backs? Its astounding how much someone felt they needed to countersink the hole for the wood screw that they used to try and reattach the neck to the violin! How would you approach repairing this blasphemy? Simply try to fill the hole as best you can with like maple? Thanks, Joe
  13. Too funny!!! But seriously. Its whatever gets the result you need.... Right? I checked my flea market cello (posted on this a few years ago) Rib height is 119 mm bottom block and corner blocks and 116 mm at neck block. And looking from the side it appears all the taper in in the neck. The back plate looks dead flat.
  14. I know right? I was excited to see Davide Sora sanding away to even out the blocks and rib structure using the same technique I use!! I thought this whole time it was cheating. But now... well...
  15. Yes, That's where I read it! Thanks! It sounds like the bend is intended to start more gradually and finish stronger. It actually doesn't sound too complicated, if you start with sanding the neck block the 1.5 mm shorter. You could approach it in a similar fashion to rounding edgework on the plates.. But I agree it is a microdetail which is likely lost in noise ...
  16. I'm on the same page as well. Its a pretty small degree flexing of the plates. It must have been easier to taper the one block and upper bout than produce a uniform linear taper over the full length of the instrument. I thought I read that originally, the taper was not linear from the upper corner block to the neck block, but rather deviated in a "curved" fashion, so the upper corner block height does not change and the rib height starts to deviate in height initially very gradually as it leaves the corner block and decreases in an gentle arcing shape as it appoaches the neck block. Or am I imagining this?
  17. Hi @Davide Sora I just have to thank you for the extraordinary amount of time and effort you must have put into making these wonderfully detailed videos. It is such a valuable resource especially for those of us who are self taught and have not had not the opportunity to work with such skilled and experienced makers such as yourself! Cheers, Joe
  18. Thanks! No I didn't know that since I've been working with a linear taper up to now. I wonder if countering the upper taper with a smaller about of taper on the stiffer back as per Davide Sora, would help counters that effect?
  19. That was going through my head as I thought through the process I have preferred, which is gluing on the top plate and setting the neck and fingerboard projection first, then gluing on the back. , Reasoning being that setting the neck angle and gluing the neck is a heck of a lot easier with the back off and you only have to deal with one gluing surface. Afterwards, planing the neck root flat to match the bottom of the neck block is completely reliable and you get a perfect fit with the back button. With the next cello build I also thought to glue the top on the ribs while they are still on the form. With a spring built into the top plate, that should still would work fine until the ribs and top are removed from the form . The garland would certainly deform slightly when the top tries to straighten. That would change the neck angle as well... But with alignment pins in the back plate and even with a slight taper to the back of the ribs , you would pull the neck block and ribs back into shape and restore the neck / fingerboard projection. This sounds like a more difficult build scenario for a violin. I can see why the neck is set on the closed box of the violin especially when a non-linear taper is involved.
  20. Wouldn't it have been present in early Strad's as well then?
  21. So you noted no differences in tonality? I love the sound on my second violin which has a straight taper. I can't help wonder how a slightly stressed top on the same instrument would sound. It's modeled after Guarneri arching. Did Guarneri instruments also follow this tapering method?
  22. Since this occurred later on in Stardivari instruments, there must have been some good reason for him to take this extra step. Just sayin' It seems that if you have tap tuned a shaped wooden asymmetric "bell" so that it rings nicely then add some longitudinal stress to the upper third of the bell you will undoubtedly be changing it's resonance characteristics. I could see that this taper would have to be subtle to not overdo the effect. Too much taper would likely suppress the ability of the "bell" to ring properly and kill the desired sound of the instrument.
  23. I'm not sure how the additional longitudinal warping of the top adds much to countering the forces placed on the top by the strings. It seems like the major player in that role is the normal arching structure of the top, locking down the perimeter with the rib garland also supported by the back. I thought the same thing that after some time the initial stress placed on the top would dissipate. Perhaps it give the instrument a better initial sound quality which might take a non-tapered instrument some additional time to develop? It might be interesting to make a violin with uniform thickness. Measure its tonal characteristics then remove the top and taper the ribs and replace the top to see how the additional stresses affect the tonality. Someone must have already done this. Thanks for you input David!