Turntable Slipping clutch

[atavid]

Yes this is that old bug bear with the Ariston.Works great when its left alone, but as soon as you fiddle it gets cantankerous.It wont work any other way with the standard AC low torque motor.I suggest you make up the two washers (lots of filing) ,find a small light conical spring and reassemble the clutch correctly with all the "d" washers in place and using a new washer made up from some stiff felt.Take everything back to standard,get rid of the tape,powder up the belt and run the TT every day for a couple of hours giving it the required push to get it going.Eventually when the assembly settles in, it will start to turn the platter by itself.Its happened to me time and time again.I just never wanted to admit that this is just the way the damm mechanism is. Just make sure your belt is not too stretched either,that wont help the speed if its not right.Here is a scan from my manual showing my clutch assembly,that may be of some help to you hopefully.Whoops,no sorry,could never figure out how to post images on this forum. Go here to see the diagram in my post.Its titled 'bearing maintenance'about half way down the page.
http://www.diyaudio.com/forums/showthre ... genumber=9[/img]

[marcoselvaggio]

Thank you so much for that. That clutch mechanism is such an odd piece of engineering. I gather the motor spindle is supposed to spin freely inside the pulley wheel untill the friction and the very gentle rotary force of the felt washer causes the two peices of brass to "grip".

When I bought the turntable it really perplexed me because the only part fo the assembly left was the pulley and the felt washer andit took me a while to get it to work at all - perhaps that's why I only had to pay five dollars for it.

I will give it a go. Thanks Again.

[atavid]

Jeez $5 you got ripped off there.....only kidding.What an absolute bargain really.Its got to be worth 50 times that just in spare parts.
Youre right about how the clutch is supposed to work,and does most of the time.Dont get lulled in to thinking that it will work if you glue the pulley to the spindle...it wont...ive tried it.... twice!The motor is very low torque and doesnt have the grunt to start the platter when it is directly coupled to the platter.As you say it needs to slip and apply turning force gradually.Get us some pics.Good luck

[marcoselvaggio]

[atavid]

Thats a fine looking RD11 youve got there.It would be a shame not to bring it back to, or exceed its former glory and sonic performance.

[marcoselvaggio]

I agree. It actually sounds quite good to me as it is (once I get it up to speed!). I didn't used to think that I was particularly discerning when it comes to sound quality, but this turntable is a dramatic improvement over my previous Dual turn table.

I must admit that I really have not much idea about the Ariston's upside potential or what changes would give the best return. I have noticed the springs are a bit soft - such that getting it reliably level is a bit of a problem - perhaps they have just become compacted with age and I should replace them.

Also I put a fairly basic cartridge on it (as someone has already observed in the Gallery!) when I first got it as I did not really know much about these turntables. Do you think ugrading that would give me a good result, and what do you think would be a good match for the AT 1007 arm?

[atavid]

My experience with the TT is that it can easily do better with better cartridges.Im using an expensive MC cart.Im not familiar with your arm though so others here may be better placed to comment on its capabilities.Dont rush into changing the springs in the hope it will make the table easier to get level.I tried some Linn black springs and their rubbers, and didnt find any improvement in setting up ability really.The sad fact is the table is a pig to set up and thats all there is to it.
Be prepared to put in a lot of time fiddling and getting nowhere,but when you do get it right,boy its a big difference,stunning in fact.I found it best to make up some blocks that raise the table enough so that i could access the springs and nuts easily.I would use these blocks in situ so that all i had to do was pull them out and gently drop the table back onto its support without having to move or shake it too much, such is the damn sensitivity of the setup.The original springs in my opinion work better on the Ariston than the stiffer Linn springs,but its not expensive to buy a set and try them.The problem with the Ariston is getting both the bounce 'pistonic like' while at the same time also getting the armboard level,centered in the cutout, and making sure the spring top rubbers dont rub on the hanger bolts.No mean feat.Same problem as its Linn counterpart.Now i dont know if the RD11 has the small indented washers fitted under the springs and above the spring nut that the RD11S has that help to "cant" the spring assembly slightly over on its side to help 'centering' and 'leveling',but if you do, dont dispose of them.I tried not using them but in the end had to concede that Ariston knew what they were doing, and that they helped.As for modifying your baby here is a link to a post i started a year or two ago.A lot of reading but lots of good info.
http://www.diyaudio.com/forums/showthre ... genumber=1

[satanfriendly]

and what do you think would be a good match for the AT 1007 arm?

If it's anything similar to the the AT1005 (which no doubt it won't be far off knowing AT) an OC9 will work wonders. If working further down the price league I can imagine a Shure M97XE will do justice.

I'm quite a fan of AT arms having had a 1005 until recently.

I must say marcoselvaggio, that is one gorgeous looking deck you have there. Gives me something to work for with my RD110 project.

Talking about 'improvements' as anyone ever changed the sub chassis for a different material? I am contemplating changing for a lightweight more rigid structure, aerolam (shows my other TT is a PT) or a CF/balsa sandwich. Looking inside I think there is room to play with alternative materials and for improvements to be made.

[marcoselvaggio]

Thanks guys for your suggestions - I will give it a go and report back.

Initially I will upgrade the cart, fix the clutch and concentrate on getting it set up just right.

I might well stop there - something appeals to me about leaving it pretty much in the form it was when it was made.... or the urge to tinker may be too great.

[bonzini]

Good people, sorry to come in late, hope it's better than never.

Marco, that's a beauty. Mine looks similar except currently sporting G707. Had a Black Widow for awhile back in the late 70s. There was a tonearm for which the right cartridge was never designed...

Anyway. One experiment I tried was to fill the subchassis (from the bottom) with melted parafin (the jelly-canning kind). This changed the overall bounce and maybe sucked up a bit of the vibration, I don't know. For awhile, about the last five years, I was kind of happy with the bounce. Then the belt broke, so I bought a new belt from Turntable Basics. My impression of this new belt is that it is a bit too small / tight / impedes the bounce overmuch. Nice belt, though, otherwise

Another thing with mine - the steel top plate is not exactly flat. This may affect the verticality of the spring posts, which may affect the bounce.

I have read - somewhere - that if you use a screwdriver to turn the spring posts on the chassis, you can modify the bounce. Perhaps! that would imply that they are not exactly straight...

Some years ago I took the foam crud out from around the spring posts. Did that help? Don't know.

You can make a new armboard (not as pretty, but that funky Scots pressboard is, well, funky) from MDF. An interesting experiment. My Grace was originally jacked up a bit on its pillar so I could use a thicker piece of MDF - 1/2" if memory serves worked OK. Better? I dunno.

Your clutch issue - haven't had that problem myself. However, mine is worse, I think - my motor shaft is slightly eccentric at the pressure pad end and the motor produces a bit of 300rpm noise above and beyond the 60hz noise.

I may one day replace my old Grace with a Rega. Cartridges these days seem to like being held firmly - who doesn't - more than back in the old V15-III days, though as I recall my 'table had a Supex 900 when it was in the store window. That must not have been a match made in heaven - vestigal tonearm and completely non-compliant cartridge. After my V15, I had an FR1-3F for several years. That was not a good match either. Latterly it has had a Linn Adikt which still throws the Grace around too much for my liking.

Good luck. A beautiful rig, that's for sure.