4Point-9 mount
A Recent Flurry ...
This is a show and tell post, along with a bit of a micro-rant.
We've had a recent flurry of custom installations, with many involving free-standing arm pillars.
We're not fans of the current crop of free-standing pillars' weaknesses.
Our key objection is to the possibility of movement - progressive "creeping" of the pillar.
When these mounts are thrust on us, we do what we can to ensure/improve the integrity of the mount - specifically, maintaining a stable pivot to spindle distance.
Bear in mind that movements as small as .25mm matter, and minimizing creep as well as addressing uncertainty is the goal.
Uncertainty
How frequently should you check it to ensure that the pod didn't "creep"? You're always wondering.
The best you can do with this architecture is to implement a Band-Aid: minimize creep and periodically verify.
Minimize
When possible, we'll machine a groove in the base of the pillar and install an o-ring to minimize slip. Higher mass pillars help.
Verify
The only way to address uncertainty is to periodically check. For this, a Feickert protractor is a quick 'n easy tool.
Kuzma 4Point-9 / TT Weights Pillar
Supatrac Blackbird Pillar
This pillar implements a Supatrac Blackbird Farpoint to a Garrard 401 - an existing design with a custom plinth having cutouts for free-standing pillars.
We implemented an o-ring on the base of the pillar, which combined with the brass pillar's mass (about 15 pounds), minimizes creep.
As with the above two mounts, we advised the customer to periodically check the pivot to spindle distance with the supplied tool.
A Better Mousetrap
Free-standing pillars have one key advantage if the above weakness can be addressed: setting up turntables with multiple tonearms is dramatically simplified by allowing you to temporarily move the left-rear tonearm to the traditional, right-rear location.
This provides much better access for working with your protractor and a USB microscope - the latter being nearly impossible to position for the left-rear mount.
We've developed a straight-forward solution to "pillar creep", and our Mk III chassis designs will implement this solution. The first chassis to employ this will be our soon to released Savoie turntable.
Stay tuned ...
