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Damping silicone for Morch UP4

John Lamb

pfm Member
Hello all and yet another query, does anyone know the correct viscosity of the silicone for a Morch UP4 tonearm I'm assuming that it is a standard throughout the range.

I have just purchased a used UP4 but need the damping fluid.

Thanks to you all
 
I need some too for the exact same arm. I had 0.4 and it takes 0.6 or suchlike.

I presumed they were all the same viscosity. I coukd see large 50ml pots on eBay for £25 or small syringes for £10. I haven't gotten round to buying any yet and will watch with interest. It sounds great with 0.4. Perhaps another 0.2 will make it more refined. Time will tell. A truly terrific arm imo. Wipes the floor with Rega / Jelco. Let's hope Mr Moerch doesn't retire .
 
It's trying to ascertain the viscosity I don't want to put the wrong stuff in :(

And yeah I now have 2 redundant tonearms hehheh
 
I use Audio Origami silicon damping fluid in my Hadcock 242 silver. Give J7 at AO a call he will know if applicable
 
Is this for the actual pivot?

If so, is it not a true unipivot, if so viscosity should count for nothing as it will move neither far nor fast enough for viscous drag to have any effect. Very different to a Hadcock where the pin slides over 4 ball bearings as it moves. The Morch is basically a pin-point contact, if you are referring to the actual pivot.
 
Is this for the actual pivot?

If so, viscosity should count for nothing as it will move neither far nor fast enough for viscous drag to have any effect. Very different to a Hadcock where the pin slides over 4 ball bearings as it moves. The Morch is basically a pin-point contact, if you are referring to the actual pivot.

I thought it was for the damping well...
 
Hello all and yet another query, does anyone know the correct viscosity of the silicone for a Morch UP4 tonearm I'm assuming that it is a standard throughout the range.

I have just purchased a used UP4 but need the damping fluid.

Thanks to you all
I'll let you know when my supplier lets me know.
 
Very different to a Hadcock where the pin slides over 4 ball bearings as it moves. The Morch is basically a pin-point contact, if you are referring to the actual pivot.

I'm not sure if you're suggesting the damping fluid acts at the pin/bearing point for the Hadcock. If you are, it doesn't. The drag is at an extension of the arm that is immersed in fluid in a cup below the arm.
 
Hello all and yet another query, does anyone know the correct viscosity of the silicone for a Morch UP4 tonearm I'm assuming that it is a standard throughout the range.

I have just purchased a used UP4 but need the damping fluid.

Thanks to you all
John, my supplier has said he will send me some. PM me your address and I'll send it on when it arrives (from Sweden!).
 
I'm not sure if you're suggesting the damping fluid acts at the pin/bearing point for the Hadcock. If you are, it doesn't. The drag is at an extension of the arm that is immersed in fluid in a cup below the arm.

I was pointing out that the Morch pivot is a genuine unipivot in that the arm sits on the tip of a pin. Hadcock pseudo-unipivot arms do not - the tip of a rounded pin sits in the gap between four ball bearings and hence the pin rides on the surface of all four.

I was curious again, because the Morch appears pretty much as an ARO, no obvious dashpot.
 
I was pointing out that the Morch pivot is a genuine unipivot in that the arm sits on the tip of a pin. Hadcock pseudo-unipivot arms do not - the tip of a rounded pin sits in the gap between four ball bearings and hence the pin rides on the surface of all four.

I was curious again, because the Morch appears pretty much as an ARO, no obvious dashpot.

On the Hadcock 242 there is a ridge at the top of the central pivot pin that the 4 balls are separated by, George worked out that 4 balls sounded better than 3 unusually however I would argue that one hole between balls with one pivot constitutes a unipivot semantics aside it works.
.
 
On the Hadcock 242 there is a ridge at the top of the central pivot pin that the 4 balls are separated by,

Not on the pins of the 228 and 242 here, even under magnification. The four balls aren't separated here either - they are essentially an exact fit in the (reamed) hole, so they touch. Both arms here are about 4-5 years old. Some very careful calculations involved to get just enough free movement to permit playing a record.

The pivot is a bit like a square-based pyramid of 4 balls at the bottom, with one in the middle, albeit the one in the middle, the pin, is pyramidal rather than round in the case of the tonearm.
The whole thing is hard-chrome plated so is VERY unlikely to wear unless seriously abused and neither here shows any sign of damage.

The design is not a unipivot because there are four sliding bearing surfaces/points. You could quite justifiably argue that it is a no-pivot at all, because there isn't one. The bearing principle is far more like an inverted version of the ball carrying the wand, floating in a liquid.
 
This thread has morched into how many balls on the head of a pin. Pity the OP.

The op has received opinions, though rather few factual answers to his question, and the offer of some free oil from what reads to be an authoritative source - a reasonable outcome I'd say.

I am still curious as to what the oil does in/on the Morch though, whether my reading of the instructions was correct.
 
I read somewhere on a Danish forum that a viscosity of 100.000 cst for a Moerch tonearm is about right. Start there and listen. Or ... better yet, listen first to what the UP4 sounds undampened, then add the silicone oil and listen again.
 
I use 250000 on mine, I struggled to find any but eventually went to a model shop that used it to damp the brakes I believe on radio controlled cars. Had the benefit of being cheap.
 
I use 250000 on mine, I struggled to find any but eventually went to a model shop that used it to damp the brakes I believe on radio controlled cars. Had the benefit of being cheap.
I bought a bottle of RC suspension silicone for my Jelco damping well, back along. Unsure what grade/viscosity it was.
 


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