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Hans Pluhar

Strad edgework

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He also shows how he does the scoop in a figure of eight ,bypassing the corners to deal with these later. There seems to be some confusion going on in this thread.

In one of the closeup photos of the Lady Blunt corners you can see the change in the surface texture between the corner where the gouge was used and the rest where the scraper was used.

Oded

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...

This is how the corners can be done for example. I use a narrower gouge and I run it through the edge of the corner. One can leave the edge straight/flush with the rest of the edge, getting a different look when applying the upper facet over the corner.

...

Very nice, Marijan! B)

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Very nice, Marijan! B)

Thank you Michael.

It would be good to hear comments from those who tried both techniques on their own instruments. It is priceless to know the difference and it is easier to theorize when debate is at least partially based on practical experience with different methods.

Michael D. Your proposal is pretty much what you can see on photos I sent, if I understand you correctly. That first facet is actually a flat (OK slightly angled) platform which determine the edge thickens. I usually do it a little narrower and I finish it to the wanted width after the plates are on. I made it in almost finished width here just for the photographs purpose.

When facet is made with file you can easily detect any uneven spots (uneven facet width) and scope can be corrected according to that, since you still have enough "meat" to work on. When your scope is clean and facet has even width all around, you can make a scribe line (or not, I still do it by eye) and file it down to the wanted width and consequently wanted thickness, if you calculated the drop of thickness correctly.

I had no problems with fragility of the edges when filing them down. Making even scope to the edge is a mater of practice and nothing else, as is making even, flat platform for "standard" method for example.

Melvin, if you use narrower gouge to flute to the edge of uniform thickness, you will end up with thinner, not thicker edge in comparison of using wider radius gouge, at the same width of the edge-crest area. You will need to take wood down more to get that width. But narrow gouge could be used under the condition that you don`t flute right to the edge.

Sorry for lousy quick sketch, but you can see what I mean. Again, perhaps I didn't understand your interpretation correctly, apologies if that is a case.

post-24003-0-28229900-1304854892_thumb.jpg

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Newb.Guad does not do it the same as the Cremonese. From what I remember and without having time to check right now, Roger Hargrave uses the diagram you posted of the corner to illustrate this difference...hence Guad's corners do not flare in width as seen from the side like Cremonese ones do.

Hello all,

Back from visiting with the Lady Blunt. Varnish observations some other time. However I was asked to check out the neck joint and purfling under the finger board.

My raw observations:

The joint between the top plate and the neck appears to be a straight line.

The edge at the plateau is a bit higher than the apex of the rounded curve of the top plate.

You can see a bit of a a ledge where the rounding off begins.

The purfling under the finger board is noticeably narrower than the prufling on either side of the neck.

The purfling channel under the neck looks like a straight line to me, parallel to the neck /plate joint.

There appears to be a mitered joint in the purfling centered under the finger board.

That's what I saw...

Joe

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Thanks Joe for checking this out!

So where are we left here? Can we figure out what method Strad used?

Platform slightly higher, then fluting, then marking, then edge roll over, then remove scribe line by finishing the fluting by scraping? I am a little confused now. There still seems to be more than one possibility. Well in the end it is not so important because the bottom line is that we have to work very precise in order to achieve a nice edge with a more or less uniform edge thickness (uniform except thicker c bouts and corners.) In any case the platform does not look like it is 4.5 mm or so as high as the corner thickness is (?)

Thanks again, Hans

Hello all,

Back from visiting with the Lady Blunt. Varnish observations some other time. However I was asked to check out the neck joint and purfling under the finger board.

My raw observations:

The joint between the top plate and the neck appears to be a straight line.

The edge at the plateau is a bit higher than the apex of the rounded curve of the top plate.

You can see a bit of a a ledge where the rounding off begins.

The purfling under the finger board is noticeably narrower than the prufling on either side of the neck.

The purfling channel under the neck looks like a straight line to me, parallel to the neck /plate joint.

There appears to be a mitered joint in the purfling centered under the finger board.

That's what I saw...

Joe

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My take on this, for what it's worth is that the wide, flat "purfling platform" idea has always seemed totally illogical and effort wasting to me. It seems far more likely that a cut was made perpendicular to the edge to define a fairly narrow flat platform all around. As I think Michael D has suggested, this may have been done with the Purfling cutter in the old days; I use a little slotting saw in my drill press. You then gouge your fluting down to the cut-in line and save yourself the effort of making a wide flat platform that you're going to gouge through later, anyway.

Facebook users should note that Neil Ertz has a fantastic set of photos on his "business" page that show his interpretation of the "hargrave" method, as well as many, many other golden nuggets of information.

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Thanks Joe for checking this out!

So where are we left here? Can we figure out what method Strad used?

Platform slightly higher, then fluting, then marking, then edge roll over, then remove scribe line by finishing the fluting by scraping? I am a little confused now. There still seems to be more than one possibility. Well in the end it is not so important because the bottom line is that we have to work very precise in order to achieve a nice edge with a more or less uniform edge thickness (uniform except thicker c bouts and corners.) In any case the platform does not look like it is 4.5 mm or so as high as the corner thickness is (?)

Thanks again, Hans

as I saw it

post-6284-0-93030500-1306187964_thumb.jpg

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I am so very sorry that the Biddulph book is so expensive. This was never my Idea at the time and I have tried to get Peter Biddulph interested in doing a cheaper paperback version, but that's life I'm afraid? However, if anyone has access to this book and can scan the series of diagrams please go ahead and put them on this site. I own the copyright on the text and these drawings anyway. These drawings explains very clearly how the edges were worked in Cremona. It is a stage further than the VSA publication although the Guadagnini piece is still about right and explains the features on his instruments pretty well. For the Cremonese method you do need to keep in mind the differences between Stad/Amati style work and working circumstances and the problems that del Gesu was dealing with. See post 201 on "Torbjorn Zethelius's note on arching heights" for an explanation. (Not Torbjorn's explanation or opinion which he is absolutely entitled to but with which I do not agree) This post also explains why the scribe lines must have been added after the channels were cut. These 'top of the edge' scribe lines were not (cannot have been) marked out on the initial flat surface. The must have been below this surface and therefore they were marked on the up slope of the channel that was cut to the outer edge.

Thanks to Chris's drawing insertion (below) you can see that the scribe lines that we see at the high spot of some Cremonese edges must have been placed on the slope of the curve 6. This would then become the high point 7. But you can also clearly see that the scribe line must have been below the original flat edge and the finished corners. It was also below the high point of the tapered button. It was clearly not marked onto the flat top surface and they did not work towards it from both sides, only from the outer side. Now, the reason why this was done has been referred to by someone else who said that it was difficult to get an even edge thickness. This is very true but, as we know the families Amati and Strad were very careful and fine craftsmen. They worked these edges very carefully. There are no traces of the gouge outside the line of the purfling, as was the case with 'big del G'. Del Gesu was working under far more difficult economic circumstances. (See first part of my book on the web site). Del G's edges were very uneven but they still swell at the corners and his 'pure' unaltered buttons are still tapered. These scribe lines were lightly applied. They are never heavy on any instrument. They were used to mark the point to which the edge must be turned. This helped keep the edge-work even and clean. Big del G. just eyeballed it. Now this system of finishing the edge has many advantages, one of which is that if you are working quickly as del Gesu often was, then if a chip occurred while the channel 6 was being cut it simply disappeared when you tuned the edge back. Using the modern method a chip to this top edge (and we all do it now and again) was either permanent or needed repair.

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Does it mean that the plateform/edge should be more like 5mm thick so that the final edge, after step 6 with the wider gouge and step 7, is about four mm thick? In this case should the purfling channel be deeper ?

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Does it mean that the plateform/edge should be more like 5mm thick so that the final edge, after step 6 with the wider gouge and step 7, is about four mm thick? In this case should the purfling channel be deeper ?

Depends on when the purfling channel was marked and cut?

Geoff

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Does it mean that the plateform/edge should be more like 5mm thick so that the final edge, after step 6 with the wider gouge and step 7, is about four mm thick? In this case should the purfling channel be deeper ?

That's about right. You can do it a little less (4.75), modern makers seem generally to prefer a slightly lighter looking edge, probably because the classical edges they see are usually worn. The real guide is the thickness of an untouched corner, remembering that even here a little cleaning up would have removed a fraction. I think that the Lord Wilton del Gesu was, (almost is), about 5mm at the corners.

As for the purfling channel ignore Geoff's comment if you are wanting to do the Cremonese method. He is of course right for any other method and I often insert the purfling after cutting the channel when I am using a more modern (not necessarily better) system. But these days I mostly use this 'Cremonese' method. And yes you do need to cut the slot for the purfling a little deeper. Strad was very smart he used a single blade which made cutting deeper easier. His blade also had a depth stop which made going too deep impossible. It takes a bit of getting used to but it is easier in the long run. Remember that going too deep in the way that the Cremonese were working (with the body glued together) would have been a real disaster.

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Hello all,

Back from visiting with the Lady Blunt. Varnish observations some other time. However I was asked to check out the neck joint and purfling under the finger board.

My raw observations:

The joint between the top plate and the neck appears to be a straight line.

The edge at the plateau is a bit higher than the apex of the rounded curve of the top plate.

You can see a bit of a a ledge where the rounding off begins.

The purfling under the finger board is noticeably narrower than the prufling on either side of the neck.

The purfling channel under the neck looks like a straight line to me, parallel to the neck /plate joint.

There appears to be a mitered joint in the purfling centered under the finger board.

That's what I saw...

Joe

I know this is an old thread but I was wondering if I could ask this question:

Did the purfling go all the way across under the fingerboard?

Thanks

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Starting to think that soft sanded edges on modern fiddles look very contrived, 
even when they're done well. 
There's an Andrea Gaurneri viola with corners like new, very little wear. 

If done beautifully, a good crisp corner with varnish on it can look great. 
I think that's what the fascination with Strad's work is actually, it's just that
all we see is the worn remnant of what he made. 
 

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So if the purfling went under the f/b and he varnished em with the f/b on, how did 

he purfle the box when it was closed. 

lol

I have asked this before and most people get a little bit upset. No one has given the answer to this:

Is the pins (that purfling is many times hiding half) the only proof for making purfling and channel after closing the soundbox.

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I have asked this before and most people get a little bit upset. No one has given the answer to this:

Is the pins (that purfling is many times hiding half) the only proof for making purfling and channel after closing the soundbox.

The Lady Blunt aside, the evidence points to no purfling under the fingerboard. Remember also that the neck was attached but there was no fingerboard yet when the plate was purfled. This and that the pins are under the purfling lead strongly to concluding the purfling and channel was done on the closed box.

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So if the purfling went under the f/b and he varnished em with the f/b on, how did 

he purfle the box when it was closed. 

lol

I've seen a pic of something with the purfling barely under the board,

maybe the channel was cut first under the board, before the top plate was glued on?

then the rest finished after lunch?

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I've seen a pic of something with the purfling barely under the board,

maybe the channel was cut first under the board, before the top plate was glued on?

then the rest finished after lunch?

I am wondering if the first owner of the Lady Blunt may have been someone very important, like the King of Spain maybe???

 

So when most violins get no purfling under the fingerboard, because no one will see it if they do not look closely,

this violin got the 'extra special' treatment and Stradivari gave the violin a nicer neater finish deserving of Royalty????

 

Who knows.

 

 

So when Joe Robson says :

"The purfling under the finger board is noticeably narrower than the prufling on either side of the neck.

The purfling channel under the neck looks like a straight line to me, parallel to the neck /plate joint.

There appears to be a mitered joint in the purfling centered under the finger board."

 

I am guessing that the purfling did go all the way across, but was probably scrap/left-over pieces of purfling that were thinner than the standard thickness of about 1.2 mm.

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