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Joe Christian

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Everything posted by Joe Christian

  1. I wonder who wrote the description - "A GOOD FRENCH VIOLIN BY JEAN BAPTISTE VUILLAUME" Machold, perhaps? Maybe the tense needs to be updated to say "WAS A GOOD FRENCH VIOLIN..." or "COULD ONCE AGAIN BE A FRENCH VIOLIN..." The way it is now you may as well add to the description along the lines of - HAS A NICE OPEN SOUND. --Joe
  2. Another thing to consider is that Potassium Nitrite is pretty hygroscopic. Personally, this doesn't seem like a good idea to me. I'm not sure how it reacts with the varnish or if it would react with any varnish that's applied so there is none left behind. It seems like it should, but I don't know. I played with it a few years ago. What I can say is that after a 3% solution was applied to wood and put in a light box, there was plenty of it left on the surface. I used a pretty sophisticated piece of equipment to test this...my tongue. There was plenty of it there. It was still active after a year (same test). Like I said, having something that's hygroscopic on an instrument seems less than ideal. No hard proof, but it seems like it could intensify humidity changes. --Joe
  3. Bill, Do you have the fence rails? I might have a fence somewhere in my parts pile. --Joe
  4. Oh! And Congrats on a acquiring a fine saw!
  5. I've had good luck with the Timberwolf blades. I didn't at first when trying to use their low tension or "flutter" method of tensioning the blades. As soon as I just tensioned them as with any other blade, they worked very well. Not sure if the Viking re-branding still recommends the flutter method or not, but just thought I'd let you know my experience. --Joe
  6. No. The idea is to remove as little wood as necessary. Just clean up the ends of the original ribs to make them straight and crisp - but retaining the existing angle. If, in fact, you are only going to have a couple of mm of filler strip showing in the end, consider orienting your filler pieces so the long grain goes from the top plate towards the button. This orients the grain perpendicular to the ribs so it's not as invisible, but it will be much easier to work the filler and it will, imho, be better than a very thin strip that is entirely cross grain. A tight fitting joint and a little creative touch-up and it will be hard to see. It'll be like when a neck mortise is filled for a neck reset and a thin sliver of the filler block is left visible after the neck is in. A mild scarf is a good thing and after re-reading Ben's post, he said "Hole in the rib" and I was too quick to notice it. Sorry Ben! This is actually a gentler scarf than a graft. A gentle scarf _can_ make the fitting a little easier (if he rib is flat). If you make it so the outer part of the rib is the long part of the scarf, it can help lock in the little filler piece. Just something to consider. A 90 degree will be the simplest and will be the least effected by any irregularities. --Joe
  7. BTW, It looks like a nice job on the doubling.
  8. I don't think that he's talking about damaged ribs. It's just some filler pieces on the side of the neck. Which, I'm actually surprised that it's going to need assuming you're putting in the original neck. But you're the one looking at it so I'll trust you. If you do the graft as Weisar describes, it's a 25mm long joint. You'll be removing a bunch of original wood from the rib which will then be replaced with the new wood. By the time you reset the neck, you'll have a few mm of new wood showing. I'm not sure that this is the best approach. On a less than valuable instrument, it's a bunch of extra work for little gain. For a valuable instrument it's removing a lot of original wood which isn't in the best preservation practices. Another thought about the scarf is that you'll have 25mm of *rib glued to rib glued to block* instead of just *rib glued to block* Just my observations. --Joe
  9. A long scarf joint like you drew has the problem of the thin outer edge being delicate and hard to blend in without getting wavy. Since this repair is over the block, you don't really need the added strength or headache of the scarf. A butt joint would work here as well as it would at the lower rib joint. Maybe a mild scarf to make jointing a little easier. Also, how much do you have to add? There isn't going to be much left after the neck is set, I'm guessing. The butt or mild scarf joint can be fit with a block plane. The next question you have is how to glue it up. I'd glue the new piece on after gluing the rib to the block. You have more control that way since you don't have a few moving parts to deal with. Just be sure to clean out any squeezed out glue when you glue the rib on. I'm sure that there are those that can do it all at the same time or maybe use the tape trick. Hopefully someone who as actually had to do this repair will pipe in and help you out. I've only had to shorten ribs. --Joe
  10. Agreed! Walking is good for the sole. The exercise will also let you sleep better which helps the winter blues a bunch. --joe
  11. When you say "ready made" do you mean purchased or stuff you made yourself? I wouldn't mix purchased varnish unless I knew the process.
  12. A well set up block plane and a final scraping if needed is a good approach. Plane or scrape one side to a finished surface. Plane the other side down using either a toothed plane iron or a plane set up with a high attack angle. This is the angle between leading edge of the plane iron and the wood. It's measured on the acute (back side) for some stupid reason rather than as it is presented to the wood. On a bevel up plane like a block plane this is the planes bed angle plus the blades bevel angle. For figured woods, shoot for 50 - 60 degrees (or 140 degrees if measured as it is presented to the wood). This essentially turns your plane into a scraper plane. The more figure, the higher the attack angle. I use a standard angle block plane. A low angle one should work too. Either way - toothed or high angle Start with a fresh edge on the iron and take as thin shavings as you can. Increase the shavings very carefully until you think you're at the edge of tear out. Back off if you need to. Expect to sharpen a few times for best results. If you use a toothed iron, It can be helpful to plane the one side until it is covered with the tooth marks and then measure the thickness. Now scrape the surface until it is just smooth and measure again. This way you can see how much to leave from the toothed plane before scraping. Add a bit of security thickness of course. All that said, .8 mm of stock removal is doable with a card scraper. I would go to 1 or 1.1 mm final thickness though, unless you have reason. That's you choice. Anyhow, by the time you get one side of the rib finished. you'll be down to .5 or .6 mm needing to be removed. If you use a toothed iron you won't be removing much before you have to start scraping again. It's good practice however you do it. Hope this helps, --Joe
  13. Hi Bill, As soon as you say the word "better" it becomes a matter of judgement. From my own experience, I will say that you can blend ready made varnishes to take advantage of the properties as long as they are of similar composition. Mixing spirit varnishes with oil varnishes shouldn't work. I say "shouldn't" because people are clever. There was a student at NBSS that was so determined that he was able to dissolve orasol dyes (that would otherwise not do so) in oil varnish by first dissolving the dyes in alcohol an then added mineral spirits drop-wise to this mix until he reached a level of mineral spirits that allowed the concoction to dissolve in the oil varnish. It worked out pretty well in the finnished film as well. I'm digressing. The properties of the wet varnish, like brush-ability and color can certainly be shifted by mixing. A varnish that is too stiff can become easier to apply by adding one that is looser. Colors also mix as you would expect in terms of hue, saturation, intensity etc. The dry film will also shift as others have mentioned above. A tough varnish mixed with a friable one will end up somewhere in the middle. Again this is from my own experience with my own varnish. Others may find otherwise. Although I haven't experience it, I suppose you can get issues with them not mixing well or strange problems like streaking, drying etc. I would suggest keeping the oils the same in both batches to be mixed. I haven't done it first hand, but my gut tells me that it's best not to mix walnut and linseed oil. Others might pipe in and tell of their experience here. Better or not is a judgement call. I have violins that have been varnished with mixed batches that are old enough now without ill effect that I trust it. --Joe
  14. That's a German style mortise. It is/was taught that way at Mittenwald. --Joe I just read the other thread after making this post. You already knew that about the mortise so what is it you're asking?
  15. I'd agree that water isn't the way to go. Time, heat and clamping. If your garage is like mine, it's probably just dampness that's causing the warping and once the back dries out it'll flatten on it's own. If not do what the others here said. I'm assuming that this fiddle isn't the most valuable since it sat in a garage for a while. So, I'm also going to suggest that after letting it acclimate to an indoor environment you just glue it up even if it still has bowing. 4.5mm is pushing it, but not out of the question. If you can close it using two fingers with an amount of pressure that wouldn't hurt if applied the pinching your own skin, the glue will hold it fine. You have the large glue surface of the block right where it is needed most. Just to be thorough, you should also let the rest of the instrument acclimate in the same room as the back. I'm sure you would have thought of that but just sayin' --Joe
  16. OK, still not sleepy so I'm going to argue with myself. On second thought, I'm going to bed.
  17. Michael, Just to play devils advocate, an audience doesn't get to take the instrument home and get used to it for weeks before listening to a performance. It's pretty much always first impressions for the audience. So, shouldn't first impressions be given most of the weight? Given a proper setting and music for the test, of course. I know the playability argument and the under the ear etc. But ultimately, it's a tool to deliver the best performance to the audience. I don't necessarily agree with this point, just making an argument cuz it's late and I'm not sleepy. --Joe
  18. What is the measurement of the warping? Are we talking a few millimeters, 10mm, 20mm, more? I'm guessing that you should be able to just glue it as it is. --Joe
  19. Sandarac does have a reputation of making a hard film. Straight jacket is one way that I've heard it described. Not sure about the silica, but it seems like it would add hard bits in a film that has its own properties. --Joe
  20. Thanks for the effort Joe. I know how hard reading is I have to correct my first statement. It should have said "proportions to match the stoichiometry" not just stoichiometry. Even that is a bit of a stretch in my mind since we're talking soup. I've also read statements of mutual solubility. Can't say how heat will affect yours since I'm not privy to your methods. I don't see any reason that reheating would cause issues with my own varnish and I haven't ever experienced any issues with drying, separation, salting out etc. Not bragging, just sayin' or just been lucky. I'm not ultra careful (or cavalier) in my methods either. Not to mention that it's being used by a number of makers for going on 20 years now and none of them have been able to break it yet. If I may brag a little - it's also been on a number of award winning instruments which is a real feeling of accomplishment. One observation that shows that there are unreacted materials (or at least extremely weak bonds) in a varnish like you describe with resin, oil and turpentine is the immediate smell of turpentine when you open the jar or apply it. The turps will also affect the re-cooking. Turps boils at around 175C the oil and resin combine at a temp that's 100C+ higher than that. The temp of the mixture won't exceed the boiling point of the turps by much (if any) until it evaporates and so, the reaction isn't going to happen. So, there's the rub as simple as it is. Many years ago I actually had a friend run my finished varnish through a chromatograph as well as samples of the original unmixed components. We compared them and found that there were unreacted components in the finished varnish. Proof enough for me. The flip side you're asking about is this: At this point I just do it. I've made it enough that I just add what it feels like it needs after trying it out on a test strip. Since I've never had drying issues or separation etc. issues, I just work on brush-ability and then the properties of the dry film. Mostly done with oil proportions in small increments - change it, test it, change it, test it, settle on something that's close enough. --Joe
  21. New approach to this major purchase? Come on down to Crazy Eddy's!!! I'm slashing the prices on all Late Model Strads! But only while supplies last!!!! What I don't sell, I'm going to Crush...I must be Craaaaazzzzyyyy!!! Or if you prefer Come on Down to Jolly John's. I'll set you up with a Modern Italian with low miles and Great handling. Remember - I'm not Jolly unless You're Happy!!!
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