New Rest Bar design for the Yamaha 456

ttf_Lawrie · Post by **ttf_Lawrie** » Sun Jun 25, 2017 10:53 pm

Some of you may recall my folding rest bar design for the Yam 456 to enable it to fit in the case.

In practice I'm not really that happy with it and have evolved another design. It is currently under trial with a buddy of mine and I hope to get some feedback at rehearsal tonight.

The design has a sliding restbar that locks into position so it won't rotate when in the playing position, BUT when slid back just 5mm it will move easily and allow you to rotate it 180 deg and slide a little further back so it will fit in the Yammie case.

The bar has a nut thread-locked to it and then a locknut is added for additional security. The clamp has a hex hole broached into it for the nut to fit into to prevent bar rotation. In addition, the forces applied to the bar when in use would naturally tighten the nut anyway.

At first I was concerned that I'd need to design some kind of anti-slide mechanism to prevent it accidentally moving backwards unexpectedly, but initial use has shown that this is not likely to happen.

Images here:
In the case - top view:

In the case - side view:

Playing position - top view:

Playing position - neck side 3/4 view:

Playing position - bell side 3/4 view:

In case - side view - half way through transition:

NOT in case - bell side 3/4 view - half way through transition:

ttf_Lawrie · Post by **ttf_Lawrie** » Mon Jun 26, 2017 5:40 am

Quote from: Lawrie on Jun 25, 2017, 10:53PM<snip>
It is currently under trial with a buddy of mine and I hope to get some feedback at rehearsal tonight.
<snip

Just back from rehearsal - my buddy is very pleased: Easy to put away and great support.

ttf_crazytrombonist505 · Mon Jun 26, 2017 1:17 pm

Very nice!

ttf_jpwell · Post by **ttf_jpwell** » Wed Jun 28, 2017 8:28 am

Is it bolt on or solder on

ttf_Lawrie · Post by **ttf_Lawrie** » Wed Jun 28, 2017 9:01 am

Quote from: jpwell on Yesterday at 08:28 AMIs it bolt on or solder on
Bolt on. The clamp is in 2 pieces and has 2 cap head screws that hold it together around the brace - a 2.5mm Allen key is supplied.

The clamp is made of brass and will not slip if fitted correctly. It is sized to be a very close fit to the brace and only needs to be tightened moderately. It's actually very hard to get wrong.

As you can see from the pics I use cork for the rest cushion - I actually recycle Champagne bottle style corks for this as those bottles are opened without a corkscrew - this maintains the corks integrity and I don't end up with extraneous holes from the corkscrew.

ttf_jpwell · Post by **ttf_jpwell** » Wed Jun 28, 2017 10:14 pm

don't see how it wouldnt just spin around

ttf_Lawrie · Post by **ttf_Lawrie** » Thu Jun 29, 2017 12:01 am

Quote from: jpwell on Yesterday at 10:14 PMdon't see how it wouldnt just spin around

That's what this bit is about:
Quote from: Lawrie on Jun 25, 2017, 10:53PMThe bar has a nut thread-locked to it and then a locknut is added for additional security. The clamp has a hex hole broached into it for the nut to fit into to prevent bar rotation. In addition, the forces applied to the bar when in use would naturally tighten the nut anyway.

ttf_Lawrie · Post by **ttf_Lawrie** » Thu Jun 29, 2017 12:01 am

Quote from: jpwell on Yesterday at 10:14 PMdon't see how it wouldnt just spin around

That's what this bit is about:
Quote from: Lawrie on Jun 25, 2017, 10:53PMThe bar has a nut thread-locked to it and then a locknut is added for additional security. The clamp has a hex hole broached into it for the nut to fit into to prevent bar rotation. In addition, the forces applied to the bar when in use would naturally tighten the nut anyway.