Bruce Carlson

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  1. Messiah wood (again....)

    The point was that Luca actually did it rather than just talking about it. He was from Trento and very near to some great tonewood sources. He knew many of the woodcutters personally. I do not subscribe to these arcane methods of wood selection.
  2. Messiah wood (again....)

    I knew Luca really well and he did admit to doing that but only on a test basis (Luca was a born experimenter). On another occasion, he went into the forest on the longest night of the year with no moon and cut a tree that turned out to be fantastic. The following year he did the same thing and he told me the tree he cut was worthless. Go figure. There's more to it than that.
  3. Interior details of Guarneri DG violins

    On instruments I have had apart, one of the main differences between the Amati violins and Stradivari/Guarneri 'del Gesù' is the rigidity of the chest area. I refer to the area on the back approximately marked out by the four corner blocks. On Amati instruments, in the geometric center of the back, can be just as thick as Stradivari or Guarneri 'del Gesù' but are usually scary thin near the linings. I'm talking about 1.6 - 1.7 mm. Stradivari and 'del Gesù' in this same location are normally over 2.5 to 2.7 mm; sometimes reaching as much as 4 mm! Bruce
  4. Interior details of Guarneri DG violins

    I haven't seen the inside work of the 1735 Plowden. Maybe you can make it out in the Strad 3D DVD published a few years ago by Sam Zygmuntowicz. Another from the same date is the violin known as 'King' which belongs to Croatia. Those c-bout linings have the diagonal cut when viewed from the side but when viewed from above (end grain of the block) appear to be set square, the lining ends don't come to a point but they are not square either. They are slightly diagonal, nor are the linings trimmed back as they enter the block like the Amati style. The 'King' violin therefore is a mix of the two styles Roger shows in his drawings. Bruce
  5. Interior details of Guarneri DG violins

    In many instances, on old and modern instruments, the purfling channel is too deep and weakens the edge considerably. It's shallow on the 'Messiah' as well. Balestrieri often cut all the way through the plate into the linings!!
  6. Interior details of Guarneri DG violins

    Well, the neck block for one, shows no trace of previous nail holes. Original lower blocks, many of which have been replaced, are not so rectangular in shape and with a smaller gluing surface. In today's making, it isn't a bad idea to have a more robust lower block because of the chinrest. The bassbar is usually inclined slightly. It is better if it not parallel also for the the reason that the stresses are distributed over more rings. It's worse if parallel to the annual rings as it would be easier for a crack along either side of the bassbar to form. In this case, the bar does appear to cross over several grain lines (annual rings). The scans are of low resolution. There aren't many of these instruments that haven't been "improved" in regards to thicknesses but in several, where I can believe that the thicknesses are undisturbed, it is the thickest area.
  7. Interior details of Guarneri DG violins

    The corner blocks are unusually small for 'del Gesù'. I wonder if someone may have trimmed them back or perhaps replaced them? Usually, as in general with the Cremonese, the c-bout rib gluing surface should be decidedly smaller than the upper or lower rib gluing surface. The neck block and the lower block are also clearly replacements. The ventral pin is visible, but to the contrary of some experts, it is not located in the narrowest point of the c-bout. In the section with the bridge, the upper linings appear to be too fat (also replaced??). The linings on the back are more what I would expect to see in cross-section. In addition, the bass-bar position is too far outside the bridge foot and over time can contribute to excess deformation around the bridge foot due to lack of support in that area. This violin is quite beautiful and I had the chance to examine it carefully when it was in Cremona but I don't think it is a good example for the internal construction details. On the video, the mortise of the linings into the corner blocks is not at all like 'del Gesù'. You would be better off looking at Roger Hargrave's drawings of this detail either in the double volume Guarneri book published by Peter Biddulph or other sources. Bruce
  8. Curious about this grain pattern in spruce violin top

    Of course, but a water stain tends to enhance it. It appears that the OP's violin was stained with something like Setzer Beize (hardly anybody calls it that anymore) which is a mixture of potassium bichromate and another oxidising agent that I don't recall right now. Hans Weisshaar had me make some up for the shop once. The formula was given to him by Frau Setzer who, according to Weisshaar, had a Pharmacy in Markneukirchen. He purchased the formula from her. Josef Hammerl calls it Altbeize (ageing stain). Josef Hammerl I believe it is n.422, noted as toxic for the presence of potassium bichromate. In addition, this effect can be created if you have a razor sharp scraper and work the spruce very smooth, avoiding the washboard effect. It is more commonly associated with sandpaper finishes. Bruce
  9. Messiah wood (again....)

    Peter, A thorough and well thought out presentation on a delicate subject that sorely needs a more scientific approach. Congratulations on a job well done! Bruce
  10. Baroque solid ebony fingerboard?

    Hi Ben, Sorry about the late reply. The board is not very long which would fit into the Amati period but I have no way to determine if it is original to the instrument. There is a manuscript repair label from Jacob Steininger in Mainz dated 1795 which overlaps the original Brothers Amati label. The instrument has been around and outside of Italy. You might want to query John Dilworth who did some work on the viola. The neck appears to have been removed at one time and a small wedge inserted between the end of the neck root and the rib, likely to raise the projection height. The neck block is in two pieces, as one finds when a part of the neck block is split away to pull the nails and remove the neck. The missing block wood is replaced and the neck re-nailed to finish the operation. The same type of operation was done to 'il Cannone' when the neck was modified at the heel to increase length. Bruce
  11. plate tuning specs ?

    It's one of the few violins that hasn't been "improved" by violinmakers with a 'pet' theory such as graduations. The blocks are quite normal for 'del Gesù', the graduations are on the thick side (see the Biddulph book on 'Del Gesù', the head is not small but deeply hollowed in the spiral, I doubt denser wood and the model is like the others with perhaps more edge overhang. The edges and edgework are still quite full. On many Guarneri violins this feature has been worn away considerably from use.
  12. plate tuning specs ?

    Absolutely. Sorry, it was not as much my intention correct you as it was to furnish more precise information.
  13. plate tuning specs ?

    The weight of the 'Cannone' is 432.25 grams strung up as Paganini played it with 3 plain gut and a wound g-string, with replicas of the original bridge and tailpiece. It still has four iron nails and the stub of a fifth nail in the neck block and heel. It also has a wedge shaped fingerboard of solid ebony like the one Nicolas Sawicki made for him in Vienna in 1828. This can account for some extra weight.
  14. Baroque solid ebony fingerboard?

    Sorry, my bad, I was thinking of the image of the underside which I believe is solid maple. The top side is veneered in ebony. Don't have the photograph with me. Anyway the early Amati boards are solid maple for sure like the tailpieces and often decorated with intertwining purfling. The board on the Hieronymus Amati Viola c.1620 in Modena is veneered spruce. The small 'del Gesù' Chardon 1735 is solid maple with a veneer of ebony.
  15. Curious about this grain pattern in spruce violin top

    Here is a cross section of end grain together with the outermost wood of the trunk which would have been in contact with the cambium layer. You can see it in the trunk surface, like bear claw scratches and you can see the dents in the annual rings caused by the irregular surface of the cambium layer. It is possible to tell if a tree has bear claw or not before it is felled, just remove a bit of the bark. The second photograph is bear claw as you would see it on a flitch of spruce ready for making. Bear claw on a Landolfi violin