Calling all Townshend Rock users!

[potatoha]

I've got a Townshend Elite Rock II TT and I've found the silicone damping fluid got really dirty with dust. I've noticed that it seems definitely thicker than what it used to be several years ago when I poured new fluid in.

I tried calling / emailing Max for several weeks to ask what CST silicone oil I could use but he's is not responding as usual.

Do any of you know what viscosity (CST) silicone oil I could use as replacement?

[Mr Kipling]

I've got a Townshend Elite Rock II TT and I've found the silicone damping fluid got really dirty with dust. I've noticed that it seems definitely thicker than what it used to be several years ago when I poured new fluid in.

I tried calling / emailing Max for several weeks to ask what CST silicone oil I could use but he's is not responding as usual.

Do any of you know what viscosity (CST) silicone oil I could use as replacement?

Not sure for certain, but I think Johnnie7 supplies it. He's a member here .

[Mr Kipling]

http://audioorigami.co.uk

Amazon have the "official" for £19.

Looking on the 'net 10,000 - 30,000 is used.

[potatoha]

Thanks Stephen. Audio Origami version is a bit cheaper. Is this of same spec as the original fluid?

http://www.analogueseduction.net/category-623/AOSIL.html

It says it can be used for SME arm damper units as well as for the Rock trough. I
read that SME recommends 30,000 cst silicone fluid for their arm, so does that mean I could use the same spec fluid for the Rock trough?

Original fluid seems just a tad too expensive, £16.98 for 10ml, considering you could buy 60ml silicone oil for £8 from most model / hobby shops.

[The Grand Wazoo]

Get some from a model car shop - it'll cost you about 20% of the hifi variety. And I mean 20%......not 20% less.
And you'll get enough to last you a lifetime.........or several lifetimes.

[potatoha]

Get some from a model car shop - it'll cost you about 20% of the hifi variety. And I mean 20%......not 20% less.
And you'll get enough to last you a lifetime.........or several lifetimes.

Yes, that's my thinking but which one (CST)?

[Mr Kipling]

I don't know to be honest. If I was buying it myself I'd get the 30,000.

[The Grand Wazoo]

I researched this subject a little when I was looking for suitable fluid for an Ultracraft arm. Actually, I think you could find that trying a range of different viscosities might give you some interesting results. You might even find that if you were fussy, different values might be needed for winter or summer!
I'm sure the 30k centistokes stuff will be fine!

[walpurgis]

I've used proprietory silicone fluids and also STP silicone oil additive (petrol engine) and it's so viscous, it works fine in my Mission arm. Just change the paddle accordingly. At about a fiver for a can at the boot sales you can't go wrong.

[potatoha]

Thanks for all your suggestions. I've just ordered some silicone oil from a local RC car shop and will let you know my findings.

[potatoha]

Right, I've sourced 10,000 and 50,000 CST silicone oil, £3.50 for 60ml bottle, from a local hobby store. Firstly, I made 30,000 CST oil by mixing them 50/50, so that I could have three different values of CST to experiment with.

Then I compared the Townshend original silicone oil, some left over stored in a bottle for several years, with 10,000 CST oil side-by-side by dipping in a cocktail stick to see how quickly the silicone drips from the end when removing it. It's not a very scientific nor accurate way of measuring viscosity, but it serves the purpose I suppose. Interestingly, the original fluid flows through a bit faster, being thinner/lighter, than 10,000 fluid, but only just. 30,000 and 50,000 CST oil are markedly thicker than the original fluid.

Anyhow, I filled the trough with three different CST values of silicone oil, one after another, and play tested with Hi-Fi News Test Record and some of my own reference recordings. Here are my findings.

A. 10,000 CST: Better sounding than the original overall. Tighter bass and less chatter.
B. 30,000 CST: Even more bass and cleaner sounding but less airy than A.
C. 50,000 CST: More bass but duller sounding overall than B.

I was really impressed with the 10,000 cst silicone as I do, very rarely, experience chatter / mistracking with the original fluid on some recordings such as Pollini's Hammerklavier on DG, but the chatter is completely gone even during the loudest passages where the original fluid had issues. As with the original fluid, it passes all the tests on Hi-Fi News Test Record with ease except for the torture track (Side 1, Band 9). Only the 50,000 CST oil just barely passes the torture track with much less distortion than 10,000 CST! I've also found that adjusting antiskate becomes almost irrelevant from 30,000 CST onward as the silicone takes care of that.

All the tests were carried out whilst the fluid leveled to about 2mm from the top of the trough and the paddle positioned about 3mm away from the bottom of the trough, i.e. the paddle is submerged around 5mm in the fluid.

I'm really glad that I've done this as I've hit the sweet spot for my setup, Excalibur + ATOC9/MLII, and I will try thinner fluid, say 5,000 CST, later on in the year to see how the temperature comes in to play. Hope you all Rock aficionados find this useful!

[Mr Kipling]

Thanks for sharing that John. I found it really interesting and will be of great help at some point in the future if I ever get my diy arm and trough to see the light of day.