Side bending

[murray kuun]

It has been many years since I made a violin. I switched to, and still make, guitars (for a living) but I felt like making a violin based on a new design (designed around ellipses).  I got some really nice AAA wood from Switzerland but I'm having severe bending/breaking problems - far worse that when I started 20 years ago.  Of the 4 strips I originally bought, only 1 remains unbroken.  What could I be doing wrong?

[David Burgess]

I don't know much about guitars, but haven't noticed any with the highly-flamed rib structure which is more typical of violins. In a nutshell, highly flamed wood incorporates variations in fiber direction, which are not present in absence of the flames. The bending techniques between the two are quite different, with bending of the straight-fibered  wood requiring hardly any skill.

Shame on you for letting contemporary guitar making corrupt you, and diminish the skills you once had.

[Dave Slight]

Before bending, are you wetting the wood? What thickness are the ribs?

[uncle duke]

1 hour ago, murray kuun said:

Of the 4 strips I originally bought, only 1 remains unbroken.  What could I be doing wrong?

Everyone's favorite fiddle making book mentions to glue material to the outside bends of rib stock to be bent.  Then scrap off the material after cooling or before gluing - strips of old bed sheet would work though linen is the term used in the book. 

[Michael_Molnar]

Don’t soak the flamed ribs. 

[nathan slobodkin]

How thick are you making your ribs? What kind of bending iron? Many years since I broke a rib but would guess ribs are too thick, not hot enough or your bending strap isn't tight enough to the rib.

[chiaroscuro_violins]

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[GerardM]

15 hours ago, uncle duke said:

Everyone's favorite fiddle making book mentions to glue material to the outside bends of rib stock to be bent.  Then scrap off the material after cooling or before gluing - strips of old bed sheet would work though linen is the term used in the book. 

What is everyone’s favourite fiddle making book.

[Jim Bress]

2 hours ago, GerardM said:

What is everyone’s favourite fiddle making book.

I started with the Johnson and Courtnall book. The books methods very closely matches my summer workshop instructors methods as they both went to the Newark School. That book also has a lot of my notes and references.

https://www.amazon.com/Violin-Making-Johnson-Courtnall-Hardcover/dp/B00ZM2HK9K

I also now use Brian Derber's book as a supplement, which is much more detailed and has better pictures. I find both useful, but if I could only have only one to learn from I would choose the book by Brian Derber.

https://newworldschool.cc/the-manual-of-violin-making-book/

[Deo Lawson]

I just bent some highly figured maple ribs for a guitar. After soaking 1 hour totally submerged in water they bent problem-free. I don't see anything wrong with soaking...

[chiaroscuro_violins]

/

[GerardM]

5 hours ago, Jim Bress said:

I started with the Johnson and Courtnall book. The books methods very closely matches my summer workshop instructors methods as they both went to the Newark School. That book also has a lot of my notes and references.

https://www.amazon.com/Violin-Making-Johnson-Courtnall-Hardcover/dp/B00ZM2HK9K

I also now use Brian Derber's book as a supplement, which is much more detailed and has better pictures. I find both useful, but if I could only have only one to learn from I would choose the book by Brian Derber.

https://newworldschool.cc/the-manual-of-violin-making-book/

Thank you Jim I have just ordered the Brian Derber book. I already  have the Johnson and Courtnall book. So I would imagine between the two of these books I will have every piece of information I need to construct a violin. Thank you again for the reply to my question take care G

[Nestor Vassiliou]

On 6/24/2021 at 5:33 PM, murray kuun said:

It has been many years since I made a violin. I switched to, and still make, guitars (for a living) but I felt like making a violin based on a new design (designed around ellipses).  I got some really nice AAA wood from Switzerland but I'm having severe bending/breaking problems - far worse that when I started 20 years ago.  Of the 4 strips I originally bought, only 1 remains unbroken.  What could I be doing wrong?

Many things could cause the ribs to break. For one low temperature. Opinions vary on what the ideal temperature is, for what its worth i bend mine at around 175 degrees celcius which is a bit on the high side. The most important thing  though is that you use a bending strap and almost your whole body weight to bend the ribs. If there are gaps between the strap and the rib, or the rib and the iron, it will almost certainly break. You should clamp down the bending iron very tightly on the workbench so you can put your whole body weight on the strap without risking flying across the whole workshop (though i suppose that would make a good youtube video ). Also a little moisture helps. I dont believe you should soak the ribs, because based on my experience it makes the rib a bit more brittle. You will get better results if you soak a cloth instead and then lightly moisten the surface of the rib with that cloth. And the most important advice I can give is to take your time. You will definetely break a few ribs in the beginning even if you do what I mentioned above. Its part of the learning process and what makes violin making so fun. Good luck 

[J.DiLisio]

There's a video floating around of Burgess bending ribs using much more force than you would think necessary.  
Clamp that iron down and give it a try.  I can attest to having much less cracking using this method.  

[Bodacious Cowboy]

21 hours ago, chiaroscuro_violins said:

When I've attempted soaking, it's always made the flames ruffled to the point where it's way more work to smooth the curves than to just bend without soaking.  

Not sure what you mean by "ruffled" but I like to see/feel some ripple or undulation in the rib flames. To me, it's something to aim for, not to avoid.. 

[David Burgess]

12 hours ago, J.DiLisio said:

There's a video floating around of Burgess bending ribs using much more force than you would think necessary.  
Clamp that iron down and give it a try.  I can attest to having much less cracking using this method.  

https://maestronet.com/forum/index.php?/topic/345821-for-those-who-have-had-difficulty-bending-ribs/

[chiaroscuro_violins]

/

[Don Noon]

Skip to 14:50 in this video: https://video.wcmu.org/video/season-11-episode-4-kwt1rd/

[Urban Luthier]

Nice video. Love the sound of sharp tools. Wonderful texture on the back of David’s violin.

[murray kuun]

On 6/26/2021 at 12:21 AM, Il Virtuoso said:

Many things could cause the ribs to break. For one low temperature. Opinions vary on what the ideal temperature is, for what its worth i bend mine at around 175 degrees celcius which is a bit on the high side. The most important thing  though is that you use a bending strap and almost your whole body weight to bend the ribs. If there are gaps between the strap and the rib, or the rib and the iron, it will almost certainly break. You should clamp down the bending iron very tightly on the workbench so you can put your whole body weight on the strap without risking flying across the whole workshop (though i suppose that would make a good youtube video ). Also a little moisture helps. I dont believe you should soak the ribs, because based on my experience it makes the rib a bit more brittle. You will get better results if you soak a cloth instead and then lightly moisten the surface of the rib with that cloth. And the most important advice I can give is to take your time. You will definetely break a few ribs in the beginning even if you do what I mentioned above. Its part of the learning process and what makes violin making so fun. Good luck 

Thanks, I had made about 25 violins back then and never had this problem.  Since this post I moved from my proper bending iron to a smaller diameter steel pipe heated with a heat gun and seemed to get better results.  I do use a strap and apply water with a cloth.  I'm now watching the video as recommended by another respondent ....

[murray kuun]

On 6/26/2021 at 4:31 PM, Don Noon said:

Skip to 14:50 in this video: https://video.wcmu.org/video/season-11-episode-4-kwt1rd/

Thanks

[Deo Lawson]

On 6/26/2021 at 7:41 AM, Bodacious Cowboy said:

Not sure what you mean by "ruffled" but I like to see/feel some ripple or undulation in the rib flames. To me, it's something to aim for, not to avoid.. 

I believe he means when the wood alternatingly swells with the flames; so the light parts are higher than the dark parts and the wood has a bumpy texture.

This does happen when I soak but it's so minor that it disappears when you do the final sanding.

[David Burgess]

Sanding?

[CaseyLouque]

Well I guess I am not alone with the learning curve on bending flamed maple...

Just bought 4 sets of sides for practice.
 

I believe that my issue was my bending iron was not hot enough only 150 c.

If i have more issues with the bending ill see if i can post a video testing the iron heat and what i am doing.

@David BurgessThanks for the video!

I will not be as shy in putting more weight/pressure on the strap this time. Hopefully I don't end up on the floor.  

though my wife might get a good laugh if that happens

[HoGo]

I just can't see any bending problems with violin ribs that are 1mm thick. I bend mandolin curly maple ribs at 2mm+ thickness and some of the bends are just as severe as violin c bouts. Takes helluva patience to bend smoothly.

One problem may be with maple that has "runout". Runout combined with heavy curl will make some parts really splitty. I would recomment using sanding belt as backing strap for those and bend slow and almost dry, it keeps the outer parts of end with less tension than using steel strap.