New Maplenoll Ariadne owner needing advice

yeah, Probably will need a hangover remedy! You might be right about the freeplay but the design i am looking at has the ability to lock the lift against the rack and support system. That is the beauty of this effort, it can be changed back if it does not work!

http://home-and-garden.webshots.com/photo/1223976996043163733nokXJH

I'm quite a bit late in this thread, but I've been watching
it for a few months now. I have some stuff which might be of interest.

Here is a Sig Ariadne that I did some revision on. Extra holes in the air bearing and some cleanup of the casting helped. A rework of the air distribution and inline regulator and filters as well as a gauge and an air switch.

Yes, I feel the original air bearing linear arm is a relatively poor design and I needed a piece in the air bearing whcih I could not reproduce. So out went the air
linear arm and in went a unipivot (I'm sure a few purists will be gesticuluating and sobbing, but it really made it
a better table). I may consider going to a modern air bearing arm at some point, but I'm currently happy with the results.

The pics are a few years old, many changes in TT stand etc. have been made. The dehydrator and air regulators and dryers have been retained, but I decided to run the
air from a standing compressor in my garage. Probably the best decision I've made yet with this table. Also now changed is the foot arrangement which now have large knurled spiked pods but retain the original threads into the table, and the left side leveling knob.

With the addition of addional air holes in the platter air bearing, it is easily floated with about 4 psi and not too much air volume. I machined up some extra center pins for the air bearing out of Delrin- if the table isn't exactly level the original will wear out suprisingly quickly.

By the way, replacement Hurst motors are available from Hurst online for about $50.

RFG

Gf gumby:

Good to have you on board. Admired your work from afar.

Do you have any pic's of your work on the lower plate of the air bearing ? Please be a tad more detailed re: "clean up of the casting helped ". Thanks

My bearing castings were a little rough. Corroded too. I was hesitant to
clean up much of the "rough cast" in the middles of the top
and bottom halves of the air bearing, as I read a looong time ago (Lumley?) that that very roughness helped by making the air more turbulent. As that memory is vague at best (I wasn't even doing analog at the time) I opted to not mess with that rough cast, thinking I could always clean it up more later. Turns out it works pretty well.

However, the wide surfaces that make contact when there is no air pressure can be cleaned up with good results. I used jewelers rouge on the flat surfaces and spun the top plate relative to the bottom plate to effectively polish those surfaces. Grit from fine sandpaper would work as well, but it's important to not sand them, you need to use the powder/grit/rouge between the plates to insure they stay consistently flush relative to each other. That seemed to allow it to float with less pressure, however it requires the table to be level
to do so efficiently and effectively. It will obviously still run at higher pressure as before, but it's not as critical to have the higher pressure to float the platter.

I also drilled and tapped two more holes in the base at 120 degrees apart the same distance as the original air inlet from the center to spread out the incoming air more evenly. That requires a little more drilling/relieving from the underside of the chassis to run the split hoses to from underneath. Make sure to re-level the bearing relative to the table upon re-assembly. Check to make sure the rubber washers between the bottom plate and the table are in good condition while you're putting it back together- you'll need them supple to take up the difference when you level the bottom bearing plate. Although a bit rough and crude, the original design wasn't too bad, but can be improved upon in these ways.

If this is "clear as mud" you can email me outside the forum.
I haven't contributed much during this thread as it has been concentrating mostly on fighting the original air arm
which I don't use for some of those same reasons. I do think the 'nolls are a neat platform that can be used as a
quite capable table, for pennies on the dollar compared to cost no object tables.

RFG

Once i moved up to a high pressure for the arm (45psig), I have not had any problem with the airbearing spindle. I have looked at your pics before and wondered why you replaced the air bearing arm. Thanks for the info. I do feel the arm is a weak link but i like the linear aspects of this arm and love the way it tracks. I have looked at ways to improve the vta adjustment and stiffness of the arm hence the tweak I am looking at. I agree the platform is excellent though a little crude compared to the beautiful tables being produced presently. But the sound stage IMO can not be found in any table in the price range you can get a used maplenoll (assuming you can find one).