Jump to content

Tostra

Members
  • Posts

    202
  • Joined

  • Last visited

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

Tostra's Achievements

Senior Member

Senior Member (4/5)

  1. I agree with that, of course. I'm not copying a specific instrument, and I definitely don't want to copy an antique cello arching. To me, shaping the arching is one of the most satisfying and interesting jobs, and I would never rob myself of that by just copying an existing arching without a very good reason. What I use cross sections for is just to compare what I'm doing with something I like the style of, as I sometimes have a hard time translating reflections into shapes. So far I've gotten close with one half of the top. It's nothing like the Davidov in its current state, I just like to compare once in a while if that makes sense.
  2. Thanks :-) No, I agree the drawings aren't exactly what I'm after, but there might be something useful in there if I need something to read one day. I actually just got the Davidov pictures. Thanks anyway! I'm still interested in any other Strad cello, as the Davidov seems quite deformed. The poster is very useful, and probably all I need right now, but more references is always better in my opinion, even if they're not the same model
  3. Yeah, that does make sense. I remember finding it in a thread, but maybe it's been removed for that reason. I'd be happy to trade for scans of Stradivari cello posters as well. I have a few violins and a Vuillaume cello I think I can scan if anyone is interested.
  4. That is the only one I can think of as well. I guess any Strad cello poster is better than none, but I have been searching for the Davidov one for a couple of years now, can't seem to find one. I think I remember seeing a thread here on Maestronet where someone posted pictures of it, but I can't find that either
  5. I agree, it's not easy to find much useful information. That's why I was hoping someone had a poster or book that was a little better. It would definitely be best if I could just borrow a strad from someone locally for a few weeks
  6. Right... I do of course agree that cross sections only tell a small part of the story. I definitely noticed that when making my first violiin, as I only used templates and was missing all of the rest. I also agree that examining instruments tells you a lot more than anything else, but I don't have that option right now. I live in Denmark, so I will unfortunately not be attenting the VSA convention either. I have however had chances to examine very fine instruments, and like I said I do have a decent idea of how I want to make the archings. My first instinct was to find as many pictures and videos of the Strads that have the sort of arching I want and look at the reflection, and I have also made cellos before which turned out nice. So I'm not searching for cross sections to male my archings from them, I am simply asking for them as a supplement/tool to guide the shape in my head and better understand the information I already have.
  7. Oh, I know that of course. But it still helps a lot to reference how they look today. I really like the cross sections on the back of Strad posters for that, but I have been searching for years and still haven't found a Forma B strad poster. I'm not trying to copy any particular arching either, I just like to see how the curves flow, preferably on a few different instruments, and then go from there.
  8. Hi I'm in the process of making a Forma B cello, and I wish I had better references available, especially for the archings. Could anyone who has a book, poster, CT scan or anything like that with a visualisation of the arching of any original Stradivari Forma B please share that with me, either as a photo, scan or file? I am just starting the archings now and have some idea of the shape, but I would like to be more certain before I go much further. Thanks in advance! Tobias
  9. That is interesting for sure. I wonder if cellulose degradation is good or bad in violins at the level alun caused here. A lot of degradation is obviously bad, but having a hygroscopic coat on a slightly degraded wood surface sounds a lot to me like "old, porous violin". Not that I'm a fan of actively degrading the wood to get a premature old sound, but it is interesting.
  10. I always assumed that it was instruments with higher/steeper archings with more exposed end grain or something like that. Like you say, the sizing is very thin, so I never thought about it. But then again, if the thin varnish layer can affect the tone, maybe the layer in between the wood and the varnish could as well. And yes, I planned to put it only on the spruce outside the instrument and all over on the inside.
  11. Hi I recently a luthier say that the reason some instruments sound dull in high humidity is that they were sized with hide glue and the protein becomes rubbery with moisture. Is this true, and in that case how about other protein grounds? I have of course heard of these wether sensitive instruments, but I haven't owned one myself. In case it is true, does anyone know how the protein changes with time? I assume that the water solubility could change when/if the proteins slowly break down, so maybe there could also be a change in moisture sensitivity. The reason I'm interested is that I have been using casein both on both the inside and outside of my instruments, and if that makes them sensitive to humidity changes, I want to change the ground. I have previously been using slaked lime to dissolve the casein, but I wanted to use Davide Sora's recipe with ammonia on the next one. Thanks in advance! Tobias
  12. Thanks. I don't have a proper bench with a vise I can use like you describe, which is the main reason I'm doing rubbed joints. I have actually had a great time doing it like that, but I should definitely try a size. I didn't think about that as a way to remedy the warping, but of course it's a good idea. And thank you. I think this cello will take me ages, but it's one I have been planning for years, and although I'm having a few issues here and there, it's very exciting to finally work on it :-)
  13. Without being completely certain, I think the problem is the wood swelling when applying glue. I've had the issue before, especially since I'm experimenting with rubbed joints. The spruce seems to "curve" away from each other, and I have solved this previously by making the gluing surface concave, which made perfectly good joints, even on cellos. This time I guess the surface was too flat or unprecise, since this only happened in the middle. I am definitely new, and I know rubbed joints aren't quite as strong as clamped ones. But I have had more luck with them personally. I really should have taken the pieces apart when I saw it starting to open up, but I checked and saw that the gap was shallow enough to keep. That must have been a bad reading though.
  14. Thanks for the advice everyone! I agree, glue shadows would be a shame, but I definitely need to get a lot closer before I dare to hollow it out. I don't use templates, so I don't yet know where the arching will be. The "pillar and wedge" idea looks great! I've done something similar in the past for cracks, but this looks way better. I'll definitely use that in some restorations as well, and it could probably be a big help here when I get to the gluing. But yeah, I think I'll stop worrying quite as much and fix the seam when I'm closer to the finished arching.
  15. Right... I would provide some pictures, but it's difficult to show. It's definitely open, maybe up to .1mm, and about 50m long. I may get past most of the open section when I carve the rel arching height, as I still have 3-4mm excess. I took this closeup with my phone, but I don't think it shows much apart from the fact that it's bad. It does have some glue in there, but it's not filled. I don't think just massaging glue in there would work. It would fill it with glue, but since the rest of the piece is solid, I don't think it will be flexible enough to clamp the top portion together until I have hollowed the plate somewhat?
×
×
  • Create New...