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sospiri

String break angle 158 degrees? Where does that come from???

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22 hours ago, Urban Luthier said:

I'm quite familiar with Roger's articles ;). I Don't see any reason why a modern maker couldn't follow a variation of the  workflow employed by the ancients - in this case the neck is dovetailed to the rib garland rather than nailed to it. Then go about the workflow outlined by Roger in the Guarneri book to scribe the outline. The neck would need a notch of course to accept the top plate

 

17 hours ago, David Beard said:

That's what I do.

Please tell me more.

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50 minutes ago, sospiri said:

It's difficult for me to tell the mortice depths from a video. Do you increase the depth from about 3mm at the top to 4mm at the button?

Yes, but I go a little deeper, about 4 mm at top and 5 mm at bottom, it is something that I very rarely measure, more than anything else out of curiosity. These measures are not significant for the purposes of neck angle and placement and may vary a little as they are determined by neck length and angle : when you reaches 130 mm with the correct angle the mortise depth is what it should be.

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I just want to point out something that people may not be aware of: I was taught (Sacconi-derived, probably) that the angle on the bottom of the neck should be 87 degrees, if I'm remembering my templates correctly. Whatever this angle is, when I was making some automated neck-setting machinery for the WH Lee shop in around 1990 I discovered that this angle provided that when the neck was placed on the end of a new instrument, resting on the uncut edge at the front, and on the rib near the button (the position when tracing to begin cutting the mortise) the neck was at the appropriate final angle to the body, with a 2.5mm edge overhang.

I thought this was interesting because it trains your eye what to look for in neck angle, right from the start of the process. Then all that's involved is keeping this angle through the process to the end. (That's for an average, normal neck set, obviously--therapeutic sets not included).

The result of this is that when the neck is finally in, it's 2.5mm deeper in the back, which works nicely with the idea that since most of the force tipping the neck forward, working to break the glue joint (no one is doubting this at this point in the discussion, right?) will be at the back of the mortise, near the button, where the glue joint is most important, deeper back there is better.

Obviously, if you believe deeper is better, then it's better to put it where needed, at the back. If you do it at the front, where not needed and the pressure is in the other direction, against the block, where you would unnecessarily weaken the block by cutting more deeply into it.

So logically, deeper at the back where needed, shallower in the front to maintain the integrity of the block, angle determined by the initial visual setting of the neck on the raw body.

I was also taught to make the neck 136.5mm long. This results in the neck stopping exactly at the inside of the purfling line, and if you subtract 2.5mm for the overhang, it put's it right at Davide's 4mm deep into the block/ribs at the front.

It's really quite elegant, and when I checked, the Sacconi? cello neck specs rendered exactly the same result--the amount of the plate overhang deeper in the back than the front--so I think it was definitely intentional.

There were a several other things I learned in restoration that were supposedly direct from the Sacconi influence in the Wurlitzer shop via one of the founders of Bein & Fushi who had worked there, and as I began to figure them out, they made the same kind of elegant sense.

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Setting the neck to the standard projection varies directly with the angle of the root heel.  So what is the ideal root angle?  It depends on what your preference for a mortise is.  If you want your mortise to be parallel with the ribs ( an even mortise) then set the root angle to 83 degrees. That means there will be no difference in depth of the mortise from top to bottom.  At 85 degrees there will be approx  1 mm difference ; at 87 degrees there will be about 2.5 mm difference.  But the average depth of the mortise depends on the length from the nut to the heel... this varies from 136 mm to 137 mm.

Personally I use a 2 mm difference.  The depth of the mortise at the top is not a strength factor since that area is in compression.

 

(thanks to Michael D for posting this years ago)

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41 minutes ago, Michael Darnton said:

I just want to point out something that people may not be aware of: I was taught (Sacconi-derived, probably) that the angle on the bottom of the neck should be 87 degrees, if I'm remembering my templates correctly. Whatever this angle is, when I was making some automated neck-setting machinery for the WH Lee shop in around 1990 I discovered that this angle provided that when the neck was placed on the end of a new instrument, resting on the uncut edge at the front, and on the rib near the button (the position when tracing to begin cutting the mortise) the neck was at the appropriate final angle to the body, with a 2.5mm edge overhang.

I thought this was interesting because it trains your eye what to look for in neck angle, right from the start of the process. Then all that's involved is keeping this angle through the process to the end. (That's for an average, normal neck set, obviously--therapeutic sets not included).

The result of this is that when the neck is finally in, it's 2.5mm deeper in the back, which works nicely with the idea that since most of the force tipping the neck forward, working to break the glue joint (no one is doubting this at this point in the discussion, right?) will be at the back of the mortise, near the button, where the glue joint is most important, deeper back there is better.

Obviously, if you believe deeper is better, then it's better to put it where needed, at the back. If you do it at the front, where not needed and the pressure is in the other direction, against the block, where you would unnecessarily weaken the block by cutting more deeply into it.

So logically, deeper at the back where needed, shallower in the front to maintain the integrity of the block, angle determined by the initial visual setting of the neck on the raw body.

I was also taught to make the neck 136.5mm long. This results in the neck stopping exactly at the inside of the purfling line, and if you subtract 2.5mm for the overhang, it put's it right at Davide's 4mm deep into the block/ribs at the front.

It's really quite elegant, and when I checked, the Sacconi? cello neck specs rendered exactly the same result--the amount of the plate overhang deeper in the back than the front--so I think it was definitely intentional.

There were a several other things I learned in restoration that were supposedly direct from the Sacconi influence in the Wurlitzer shop via one of the founders of Bein & Fushi who had worked there, and as I began to figure them out, they made the same kind of elegant sense.

Now that is what a Maestronet post should look like. I use an 87° heel angle, and it works exactly as you describe. Thanks Michael! 

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42 minutes ago, catnip said:

Setting the neck to the standard projection varies directly with the angle of the root heel.  So what is the ideal root angle?  It depends on what your preference for a mortise is.  If you want your mortise to be parallel with the ribs ( an even mortise) then set the root angle to 83 degrees. That means there will be no difference in depth of the mortise from top to bottom.  At 85 degrees there will be approx  1 mm difference ; at 87 degrees there will be about 2.5 mm difference.  But the average depth of the mortise depends on the length from the nut to the heel... this varies from 136 mm to 137 mm.

Personally I use a 2 mm difference.  The depth of the mortise at the top is not a strength factor since that area is in compression.

 

(thanks to Michael D for posting this years ago)

This is not always the case as rib structures on older violins can vary from top to back.  We calculate the heel angle directly from the measurements of the instrument being worked on, and as I mentioned earlier, I prefer the look of the overstand when it is coming from a parallel mortise/ parallel to the ribs,  but that is just preference.

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1 hour ago, Michael Darnton said:

Obviously, if you believe deeper is better, then it's better to put it where needed, at the back. If you do it at the front, where not needed and the pressure is in the other direction, against the block, where you would unnecessarily weaken the block by cutting more deeply into it.

Seems to me if sospiri uses his 90 degrees or you use Saconni's 87 degrees you guys will be going in deeper into the neck block.  I don't see this as being less evasive than using an 83 degree. 

I took into consideration you may not of remembered the correct angle from long ago.

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1 hour ago, catnip said:

  If you want your mortise to be parallel with the ribs ( an even mortise) then set the root angle to 83 degrees. That means there will be no difference in depth of the mortise from top to bottom. 

Every one of my neck setting episodes [14]? have used the 83 degree heel angle and I've always had to make the lower part of the mortice/pocket deeper as compared to the upper section. 

I should mention that I don't conform to prescribed fingerboard for violin specs when doing this though.

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50 minutes ago, uncle duke said:

Every one of my neck setting episodes [14]? have used the 83 degree heel angle and I've always had to make the lower part of the mortice/pocket deeper as compared to the upper section. 

I should mention that I don't conform to prescribed fingerboard for violin specs when doing this though.

We put necks in violins at 6 mm and cellos at ten with even depth.  But, I am curious why do you not conform to prescribed fingerboard specs?  Just curious.

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I go deeper at the button end of the mortise, the notion being that this gives the bottom of the heel more purchase on the stronger part of the back, inside the purfling.

Of course, if this portion inside the purfling breaks out with the neck, it is much more difficult to repair than just a broken out button. :blink:

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7 hours ago, sospiri said:

I'm assuming it must 

You seem to hang on to many baseless assumptions as if they were sacred.

You might consider cultivating more room between thinking 'maybe?', and turning that into 'this MUST be'.

 

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7 hours ago, sospiri said:

Right. So arm waving hubris is ok as long as it's directed at genuinely stupid people like me?

No, I'm not sure if you are stupid, but you sure are rude, seem to lack social skills, have an air superiority while at the same time seem to be woefully ignorant about what you are talking about. Have come to ask questions, yet seem to be the one who wants to give the answers, have told some of the most respected builders alive, who nicely took their time to try to help you, "they don't get it" when they most certainly do. 

So I don't call what I am doing "arm waving hubris". I call what I'm doing telling you directly, me to you, that I think you are,  rude, ignorant, stubborn and come across like a fool and have demonstrated behavior that will most likely not serve you well as far as people who "understand" trying to help you out in the future. 

Your statement also demonstrates a lack of understanding in that you are the instigator here, you are the one that is the problem, not me. I'm just taking the time to point it out.

You seem woefully unaware that punishment comes with bad behavior, your statement makes it sound as if I'm attacking some poor innocent guy who just wanted to get some help, and me with my superior self is just coming in here and throwing hubris around for no reason other than just to put stupid little you down. Poor you, right? 

The funny thing is you probably think your behavior is "ok"? I really think you need to go to your naughty spot and think about the way you've behaved here. For a clue,  the big "D" on your cap does not stand for "Dunce"

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46 minutes ago, Jerry Pasewicz said:

We put necks in violins at 6 mm and cellos at ten with even depth.  But, I am curious why do you not conform to prescribed fingerboard specs?  Just curious.

At the time I used Goldblatt's violin specs when it was time to make fingerboards.  The suggestion was 5.5 mm so I made the first 7 or 8 fingerboards using 5.5 mm throughout along with the relief and everything else that goes along with fingerboards for new work.  Thought that was good enough.

Sometime afterwards.....................I finally learned how to read the Heron-Allen book,  paid attention to the words and applied the readings to wood.  Quite a bit of difference between Goldblatt's specs and Chanot's recommendation.   I've done 4 or 5 with the Heron-Allen heights and I prefer those rather than the higher heights, which will be adjusted eventually to the lower specs as per Chanot..  

I guess one could say I still do conform to prescribed violin fingerboard specs -they are just different specs than what I started with previously.  

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29 minutes ago, David Burgess said:

I go deeper at the button end of the mortise, the notion being that this gives the bottom of the heel more purchase on the stronger part of the back, inside the purfling.

Of course, if this portion inside the purfling breaks out with the neck, it is much more difficult to repair than just a broken out button. :blink:

I am assuming either way you do not have many necks popping out......just a wild guess.

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3 hours ago, uncle duke said:

At the time I used Goldblatt's violin specs when it was time to make fingerboards.  The suggestion was 5.5 mm so I made the first 7 or 8 fingerboards using 5.5 mm throughout along with the relief and everything else that goes along with fingerboards for new work.  Thought that was good enough.

Sometime afterwards.....................I finally learned how to read the Heron-Allen book,  paid attention to the words and applied the readings to wood.  Quite a bit of difference between Goldblatt's specs and Chanot's recommendation.   I've done 4 or 5 with the Heron-Allen heights and I prefer those rather than the higher heights, which will be adjusted eventually to the lower specs as per Chanot..  

I guess one could say I still do conform to prescribed violin fingerboard specs -they are just different specs than what I started with previously.  

I don’t remember those measurements in there, I haven’t looked at the book for 3 and a half decades, but I will have a peek.  I must say, however, I recall Heron-Allen always reading to me as if he was an annoying guy that kept coming around to violin shops,  and the violin makers would just tell him stuff to screw with him and see if he would buy it.........I recall it being more entertaining when I kept that in mind..

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3 hours ago, Jerry Pasewicz said:

I am assuming either way you do not have many necks popping out......just a wild guess.

Never seen one of David's necks come loose on their own...

 

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Just now, Jeffrey Holmes said:

Never seen one of David's necks come loose on their own...

 

He must be using some tricky, new fangled technique.......

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BTW: I removed a couple of posts that attempted to bring the old dovetail discussion debate back... sorry... that discussion was getting old before.  

While I am easily able to find the heel of the neck referred to as having a slight dovetail in writings found elsewhere by a good number of luthiers (some who post here), wikipedia, and other instrument related sources (including my old school notebook), I honestly don't care what you all choose to call the neck joint (mortise, dovetail, dovetailed mortise, etc.).  Ignore the dovetail reference it or write it off as fake news if you wish, but please just try to do it right. OK? 

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3 hours ago, Jeffrey Holmes said:

BTW: I removed a couple of posts that attempted to bring the old dovetail discussion debate back... sorry... that discussion was getting old before.  

While I am easily able to find the heel of the neck referred to as having a slight dovetail in writings found elsewhere by a good number of luthiers (some who post here), wikipedia, and other instrument related sources (including my old school notebook), I honestly don't care what you all choose to call the neck joint (mortise, dovetail, dovetailed mortise, etc.).  Ignore the dovetail reference or write it off as fake news if you wish, but please just try to do it right. OK? 

Dang it, Jeffrey, using some sort of "correct" terminology is essential to making the neck stick to the body, isn't it? ;)

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3 hours ago, David Burgess said:

Dang it, Jeffrey, using some sort of "correct" terminology is essential to making the neck stick to the body, isn't it? ;)

That's why I call mine the "Norton Bald Eagle Tallywacker"  you don't know the origin of the name, who came up with it{maybe Norton?}, if it's even the right name for it, but boy you never forget when your doing it.

Also, as you know we don't like to "talk about certain stuff" you know, give out too much information, this just adds one more layer of secrecy. I was thinking we could come up with some Latin like language to obfuscate things even more. You know, something like "Nortunius Baldus Eaglonous Tallywakus" That way no one will ever be able to figure any of this crap out. That way we can keep.... "the secret"  :rolleyes:

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20 hours ago, David Burgess said:

Dang it, Jeffrey, using some sort of "correct" terminology is essential to making the neck stick to the body, isn't it? ;)

:) 

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17 hours ago, jezzupe said:

 That way no one will ever be able to figure any of this crap out. That way we can keep.... "the secret"  :rolleyes:

People can't resist saying everything they know.  That's why the internet has so many 10 page threads on how to change a light bulb.  If they don't say it, they don't know it.  Same reason interrogations last all day.  Gonna eventually say it if he knows it, or explode.

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