Nut Rollers

chris ivey · Post by **chris ivey** » 15 Feb 2016 7:37 am

when will you have a working model?

Justin Griffith · Post by **Justin Griffith** » 15 Feb 2016 3:57 pm

Chris Templeton wrote:When I spent time with Ned Steinberger, he often spoke of the knife edge roller nut. He has used that nut design with his tremolo and Transtrem systems.
I've always wanted to see a steel changer that uses the knife edge design.

Like a Blanton? I'll dig out a photo.

Justin Griffith · Post by **Justin Griffith** » 15 Feb 2016 4:04 pm

Justin Griffith · Post by **Justin Griffith** » 17 Feb 2016 5:56 am

Georg SÃ¸rtun wrote:I like the look of the Blanton with main fingers/bridge-rollers on knife-edge and what appears to be enforced sides. Is the rest of the changer (scissors) also based on knife-edge connections?

The changer finger has a rivet like most. I'll dig one out later and post a pic. Most of them were steel, but some were brass (and sound amazing)

If Jerry wasn't the first person to use an all pull finger, he was one of the very first. He's a genius for sure. Nice guy too!

Jim Pitman · Post by **Jim Pitman** » 19 Feb 2016 9:54 am

Geoerge S. thought I'd pass this on to you.
http://www.emachineshop.com/machine-shop/index.php
It's a machine shop that supplies a reduced Solid Works software package for free that is customized for their capabilities. I found it quite easy to learn. It provides realistic 3D modeling/rendering.
I like it because once you are finished drawing something you can get an instant quote with delivery, then fool around with qntys/materials/refinemenst to see how it affects the price.
For large quantities it may not be competitive with a traditional machine shop, but we hobbyists rarely need a large quantity of anything so you kinda pay through the nose anyway regardless who you have do it.

Bobby D. Jones · Post by **Bobby D. Jones** » 20 Feb 2016 2:05 pm

Georg you have great old and long proven engineering principal in this design. It has been used for centuries as a pivot point. It is the knife edge principle for mechanical weight scales. You turned 180 degrees. and now the knife edge is on the bottom. On scales the knife is on the top as the frictionless pivot for the beam. You will need some way to keep the top piece captured in place. If you broke a string on stage would the pivot piece on top go flying for location UNKNOWN. I am just suggesting, Secure it to save hunting for it. Good Luck in this adventure.

Stephen Williams · Post by **Stephen Williams** » 20 Feb 2016 2:08 pm

3D printing? Now you can print in steel it should be possible to make cheaply. i have not found anywhere yet. has anyone?

Will Cowell · Post by **Will Cowell** » 21 Feb 2016 2:58 am

Georg, I'm puzzled about how the "lower" finger will stay in place. As drawn, the raise finger will exert a sideways force on its pivot point, which will pull the corresponding part of the lower finger (the knife-edge) to the right. How will you stop that happening, but still allow the lower finger to pivot to the right under the action of the lower pull-rods?