Scrapers at the Museo del Violino in Cremona

[Davide Sora]

9 hours ago, LCF said:

A  forensic analysis might attempt to match striations on the wood surface of his violins with the details of the scraper edges.  

I don't know what the old Cremonese equivalent of the modern cardboard box or milk crate might have been but I can imagine that in the end days of a formerly busy workshop there would been boxes full of miscellanea in every dusty corner. The scrapers might have been in one of those - not very useful but too good to throw out.  

 

Yes, furthermore the provenance of these scrapers is not 100% certain, they could also be from Ceruti's workshop, but given the probable provenance from the Fiorini donation, they would be lumped together with the provenance of the other Stradivarian finds. Investigations should be made in the (rather confusing) papers of the various donations of finds, and the museum curator told me that he would like to also have an analysis of the metal done, let's hope they don't find something like chromium or molybdenum which would make them date back to more recent times. But I don't think so, it looks like very old steel. Who knows, perhaps by analyzing the encrustations present, they would find traces of clay, which would make them out of the picture for violin making. But I think this is also quite unlikely. In any case, I don't think these analyses will be done any time soon if they are ever done at all. There are a lot of finds, and each one deserves in-depth analysis, but as usual money is not so easily available, in addition to the problems related to conservation.

[David Beard]

I believe the ancient tradition was to make scrapers from broken fighting blades, as these represented the highest carbon and stiffest steel.

This also suggests that such scrapers were generally double beveled and sharp, not a turned burr as in modern style card scrapers.

It also suggest their first concern in the quality of scrapers was hardness and heft.   Shape was largely happenstance from the shape of the the original blades.

Altogether, a very different concept of scraper from the common modern idea.  I believe the story for turned burr scrapers is that the style arose from using old panel saw blades as the source of scraper steel instead of broken fighting blades.

 

[Andrew tkinson]

1 hour ago, David Beard said:

I believe the ancient tradition was to make scrapers from broken fighting blades, as these represented the highest carbon and stiffest steel.

This also suggests that such scrapers were generally double beveled and sharp, not a turned burr as in modern style card scrapers.

It also suggest their first concern in the quality of scrapers was hardness and heft.   Shape was largely happenstance from the shape of the the original blades.

Altogether, a very different concept of scraper from the common modern idea.  I believe the story for turned burr scrapers is that the style arose from using old panel saw blades as the source of scraper steel instead of broken fighting blades.

 

Hello David and Davide, in the book " The Vihuela de Mano and The Spanish Guitar" by Jose L Romanillos Vega and Marian Harris Winspear, there are some translations of some 16th or 17th century luthier workshop inventories which mention something like "broken sword tips". I think I might have seen other mentions of pieces of old sword blades in other ancient instrument maker's workshop inventories but my "archive" - piles of paper lying in bags and boxes - of this information is about as badly organised as I am so I can't provide exact quotations at present! Maybe someone else on Maestronet may have the book close at hand and can give more exact information?

(This blade recycling still goes on today as a couple of years ago I bought an old screwdriver from Ireland on ebay and it had been made from an old bayonet which I think may have been Austrian as it has a faint double headed eagle stamped on it)

In this same book there are also some translations of the surprisingly wide range of work the craft guild required a maker to be able to perform in a short amount of time to be admitted as a master of the craft at this time. 

 

[LCF]

10 hours ago, Davide Sora said:

... the museum curator told me that he would like to also have an analysis of the metal done, let's hope they don't find something like chromium or molybdenum which would make them date back to more recent times. But I don't think so, it looks like very old steel...

Metal analysis is fast and easy nowadays using a handheld Xray Fluorescence Spectrometer (XRF). Larger museums might own one or at least employ a contractor who owns one. They are common in mining industries. 

 

[Davide Sora]

4 hours ago, David Beard said:

I believe the ancient tradition was to make scrapers from broken fighting blades, as these represented the highest carbon and stiffest steel.

This also suggests that such scrapers were generally double beveled and sharp, not a turned burr as in modern style card scrapers.

It also suggest their first concern in the quality of scrapers was hardness and heft.   Shape was largely happenstance from the shape of the the original blades.

Altogether, a very different concept of scraper from the common modern idea.  I believe the story for turned burr scrapers is that the style arose from using old panel saw blades as the source of scraper steel instead of broken fighting blades.

 

You may be right, especially about the origin from sword blades, probably the best steel that could be recycled to make tools at the time. But the blacksmiths who made the swords could also make tools with the same forging techniques, therefore with the same quality of steel, so even the origin from the swords is not at all certain, one of the many things we can only guess but will never know for sure.

The same goes for the scraper shapes, it seems strange to me that they relied on the shapes they obtained randomly from the pieces they found without modifying them, they had grinding wheels and they certainly knew how to use them masterfully, the shape of the scrapers (especially those for the scroll details and edge fluting) is very specialized and must fit the shape you want to get, if you have a shape that doesn't work you modify it to adapt it to your needs, today as then.

Regarding sharpening, they were probably used as simple cutting blades, but here too there is no certainty and/or evidence. When I examined the scrapers, the majority had no trace of burnished wire, but they didn't feel sharp either, you can run a finger over them even with some pressure without fear of cutting yourself, and this could be interpreted as scrapers for pottery, not for woodworking. Instead, one had the wire clearly burnished, and another had traces of burnished wire somewhere. But too many years have passed, and many other hands may have intervened in both cases, so we can just make unsupported guesses.

 

[Davide Sora]

14 minutes ago, LCF said:

Metal analysis is fast and easy nowadays using a handheld Xray Fluorescence Spectrometer (XRF). Larger museums might own one or at least employ a contractor who owns one. They are common in mining industries. 

 

They have one in the non-invasive diagnostic laboratory hosted at the Museum. But the laboratory is from the University of Pavia, only hosted at the Museum (therefore different institutions) and the relationships are not so immediate and a little complicated.

Welcome to Italy!

[Davide Sora]

4 hours ago, Andrew tkinson said:

Hello David and Davide, in the book " The Vihuela de Mano and The Spanish Guitar" by Jose L Romanillos Vega and Marian Harris Winspear, there are some translations of some 16th or 17th century luthier workshop inventories which mention something like "broken sword tips". I think I might have seen other mentions of pieces of old sword blades in other ancient instrument maker's workshop inventories but my "archive" - piles of paper lying in bags and boxes - of this information is about as badly organised as I am so I can't provide exact quotations at present! Maybe someone else on Maestronet may have the book close at hand and can give more exact information?

(This blade recycling still goes on today as a couple of years ago I bought an old screwdriver from Ireland on ebay and it had been made from an old bayonet which I think may have been Austrian as it has a faint double headed eagle stamped on it)

In this same book there are also some translations of the surprisingly wide range of work the craft guild required a maker to be able to perform in a short amount of time to be admitted as a master of the craft at this time. 

 

Yes, one of the reasons why the hypothesis of sword blades is often made is precisely because this reference is found quite often in literature.

[LCF]

1 minute ago, Davide Sora said:

They have one in the non-invasive diagnostic laboratory hosted at the Museum. But the laboratory is from the University of Pavia, only hosted at the Museum (therefore different institutions) and the relationships are not so immediate and a little complicated.

Welcome to Italy!

Perhaps they could invite a mining company to bring one in pro bono and generate a little favourable publicity with the the Stradivari name attached to it, a glossy magazine article etc., testing all the various metal tools in the collection at the same time. I suppose it might put other noses out of joint but that could be a good thing! 

[Davide Sora]

1 hour ago, LCF said:

Perhaps they could invite a mining company to bring one in pro bono and generate a little favourable publicity with the the Stradivari name attached to it, a glossy magazine article etc., testing all the various metal tools in the collection at the same time. I suppose it might put other noses out of joint but that could be a good thing! 

I don't think there is a real opposition between the museum and the laboratory, just a lot of bureaucracy and regulations to deal with, even if a little goodwill on both sides wouldn't hurt. We will wait hopefully, I can live without the scientific tests, even if they would satisfy some curiosity.

[Greg Sigworth]

On 12/1/2023 at 8:43 AM, Ch. Dequincey said:

I’ve been looking at making scrapers based on those in the collection at the Violin Museum in Cremona  (MS 691 up to MS 697). To work out their outlines, I’m using the pictures and measurements provided by  the catalogue of their collection  . (https://museodelviolino.org/en/nuovo-libro-antonio-stradivari-disegni-modelli-forme/). 

During the process a few questions came up and I’m wondering if participants of this forum would have answers? 

1)While resizing the outlines to the measurements provided by the book, most of them worked pretty accurately besides the MS693 which seems slightly narrower when proportionally adjusted to length and most importantly the MS696 which is about 6mm longer when proportionally adjusted to the width measurements.  

As the book gives the exact same measures for the MS696 and the MS697, the latter fitting within the measurements provided.  

I’m wondering if it could be a mistake during the data recording/entry? Or a photo distortion that could have happened during the editing? Something else? 

(please ref to snapshot provided, the frame representing the size provided in the book). 

2) Has anyone had a chance to look at them out of their display box? And if so, have measurements of the MS696? 

3) Is there any record of their thickness available? 

4) Are there bevels on one side only or on both sides for each of them? 

 

Thank you for your insight,  

 

Thanks for the picture. Made one like it from some old scraper material. It works well and is handy size.

[David Beard]

On 1/2/2024 at 2:19 PM, Davide Sora said:

You may be right, especially about the origin from sword blades, probably the best steel that could be recycled to make tools at the time. But the blacksmiths who made the swords could also make tools with the same forging techniques, therefore with the same quality of steel, so even the origin from the swords is not at all certain, one of the many things we can only guess but will never know for sure.

The same goes for the scraper shapes, it seems strange to me that they relied on the shapes they obtained randomly from the pieces they found without modifying them, they had grinding wheels and they certainly knew how to use them masterfully, the shape of the scrapers (especially those for the scroll details and edge fluting) is very specialized and must fit the shape you want to get, if you have a shape that doesn't work you modify it to adapt it to your needs, today as then.

Regarding sharpening, they were probably used as simple cutting blades, but here too there is no certainty and/or evidence. When I examined the scrapers, the majority had no trace of burnished wire, but they didn't feel sharp either, you can run a finger over them even with some pressure without fear of cutting yourself, and this could be interpreted as scrapers for pottery, not for woodworking. Instead, one had the wire clearly burnished, and another had traces of burnished wire somewhere. But too many years have passed, and many other hands may have intervened in both cases, so we can just make unsupported guesses.

 

Ah, only almost.

Swords were made to be high carbon sharp edges, but with some toughness/softness so they could be used with force.

Broken fighting blades represent not just their original blacksmith, but a further step of selection.  Steel smithing was not highly consistent or predictable as now.  Broken swords means the ones that had even more carbon, blades that therefore harder but also more breakable.     Ultimately bad for fighting, but better for scraping.

That's probably the same reason the early stories of burr scrapers begin from again from recycling Broken steel, this time from panel saw blades.   Same issues.   The breaking represent a further selection of the too high carbon examples from a type of steel already made to be quite hard.