Building high-end 'tables cheap at Home Despot II

Oregon & Jean: thanks both. I will try both ideas and let you know. The power of this thread is so formidable that when I was fooling around yesterday (with my wife's help listening) she was the one that said "you should post the problem on your favorite thread."

Ladies and gentlemen, for my wife to reach this opinion, well let's just say we've penetrated well down into the masses!

Thanks Jean, I'll tell you where to send the royalties :)

Mike

Hi All,

First, let me offer apologies for “My System” which resembles the untidiness of a flophouse. Instead of coherent exposition, there resides jumbled teasers. Someday soon, I must pursue some tutorial help in getting it order. Anyway, Chuck got hold of me and now has the MuMetal/Lenco application recipe and I believe he’s going to pursue the fix – a fix that will utterly banish motor generated EMF hum.

Work continues on my automated record-cleaning machine. Already there have been departures from Jimmy Neutron’s machine. The plastic gear drive interface between the ice cream maker motor and the cleaning platter had too much slop in my design which translated into wobble. This called for the introduction of a 12” “Lazy Susan” bearing assembly for the platter to ride on. With 80 balls this is quite the rumbler! A neoprene-lined chamber within “plinth” will house the 3 hp DustDevil vac motor and have a fabricated mini-furnace filter to keep cleaning fluid off the motor (fused – just in case).

Looking forward to visiting Ottawa in ten days or so to hook up with Grant for a CD release (mastered by our very own - gjwAudio1 – aka Grant) party featuring Terry Gillespie and The Granary Blues Band. Weather permitting, my wife and I hope to pay a visit to one of Jean’s old Archeo haunts, Bon Echo Park.

And maybe, just maybe… another Lenco.

Hey Mike,

You’ll have to split those royalties with Mr. Red Green.

- Mario

Who dat?

Mario, I was thinking, now that I am getting close to a two or three armed monster, you covered the platter with the mu-metal. Did you try to cover the motor first - i.e., attach shielding to the bottom of the Lenco's top plate over the motor's coils? Visualizing it, it doesnt seem impractical(?)

Mike - who has a cousin named Blue; fortunately, last name not Greene :0)

Mike, as I imagine an electro-magnetic field to work, the waves are not absorbed but are deflected by mumetal. If I am right, then the waves would flow out and emerge around the edges of the motor - still interacting with the cartridge as it plays the record. When the shielding is done for the platter, this flow around the barrier would also happen, but shielding the platter would disperse the field to the outside of the record and the interference would occur outside the playing surface of the record.

I had also thought of shielding the bottom of the platter rather than the top - this way you won't have to be so particular at adhering it. But I'll have to wait until I see the material in the flesh. Mario, is there any reason for doing the top versus the bottom?

Of course, I may be full of hot air here and this is a guess based on my extensive ignorance of electro-magnetic fields.