RB301 Spring Not Disengaging.

[Wozza]

Hi,

My RB301 doesn't seem to want to disengage its spring. I have just installed a Michell Tecnoweight and the instructions state to disengage the spring by dialling in to 3.5 on the VTF, but nothing happens.

I had to set up the Tecnoweight by setting the VTF to 0.

I have a P5 in the house and that clearly disengages when set to 3.5. You can also hear the spring being disengaged on the RB700 too.

Is this common with RB301's?

Cheers.

[JaS]

I'm not sure what you mean by disengage the spring? Tracking force is adjusted by means of a coiled spring which applies an upwards force. Setting the dial to maximum will reduce this force, but nothing in the mechanism is disengaged

Regards,
JaS

[Wozza]

Hi.

Maybe disabling is a better word. This clearly happens on the RB700 I have. But doesn't work on my RB301.

[JaS]

I'm not sure then? It's not easy to tell if the spring is unwound to a point where it's having absolutely zero effect on the balance of the arm without physically taking the cover off and having a look at it. It shouldn't make any difference to the working of the Tecnoweight, but if you are trying to reduce ringing of the spring then IME simply unwinding it to max makes no audible difference anyway. YMMV

Regards,
JaS

[Wozza]

If the spring won't disengage I think I'm going to try setting 1g on the VTF dial and the rest counterweight or all VTF.

I will have a play tomorrow.

Thanks.

[Wozza]

Hi.

Ok after reading the internet a little I think I understand it more.

VTF set at 0 = Maximum spring force
VTF set at 3.5 = no spring force.

So I don't really understand why the Tecnoweight manual says set at 3.5 and then balance your cart. For me that is impossible.

I'm using the heaviest weight, which is suitable for 6 - 13 grams. My cart is only 8g, yet I can't balance and I'm no where near balancing the cart. I have even shifted the tecnoweight back 8mm on the slide bush like it says in the manual (for carts heavier than 13g!) and I still can't balance.

If I set the VTF dial to 3.5 and leave the weight 8mm back I can get my cart to weigh VTF 1.75g, but the technoweight is far back on the slide bush and the slide bush is really way back on the stub. This seems to contradict the whole point of the TW i.e. close to the pivot bearings.

So I'm at a loss as the best way to set it up now.

Also, my RB700 I have (not set up) behaves the same as my RB301. I have put some little weight on the head and it exhibits the same behaviour.

So it looks like my RB301 is acting normally and 3.5 on the dial is disabling the spring.

Scratch head time

[Wozza]

The only other thing I can think of is maybe my cart is too far forward in the head shell? Visually it does look quite forward.

I used the Vinyl Engine Bearwald Rega two point protractor and it hits the two dots perfectly. It have been tracking the inner grooves lovely right up till the label.

Maybe I could try the Stevenson or go for the Bearwald again but push the cart slightly back a bit?

[JaS]

I'm guessing that Michell say to set VTF to 3.5g as this makes the arm static balanced when using their weight. I used the Tecnoweight this way on an RB300 and an RB250 with a 6.5g cartridge and didn't have any issues FWIW I was using Baerwald alignment which does push the cartridge 2.3mm further forward than Rega alignment.

Regards,
JaS

[Wozza]

This Tecnoweight is a waste of time.

I've pushed my cart right back in the headshell and it still won't balance and if I do try it get my tracking force its miles away from the pivot.

"The TecnoWeight will handle a wide range of cartridges, with weights from 3g to over 13g"

This is wrong surely.

I would have been better off getting the Rega Tungsten heavyweight rather than this garbage.

£80 down the drain.

[Werner]

Interesting.

The TecnoWeight has been on the market for over 8 years. Thousands are in use.

And now you discover it can't balance a 6g cartridge.

[nabil]

Interesting.
The TecnoWeight has been on the market for over 8 years. Thousands are in use.
And now you discover it can't balance a 6g cartridge.

I agree with Werner; there must be something else going on. If this were a universal problem with the TecnoWeight then we, the Rega community, would know about it. That it is happening on both of your Rega arms-RB700 and RB301-my guess is that you received a damaged product. I hope that you get this sorted out.

[tomytoons]

I use the Techno weight on an RB 700 and it works fine.
Forget about balancing the arm. I NEVER balance it. It is set all the way to 3.5 or past on the dial.
I go from there and set the "vtf" vertical tracking force to my needed 1.8 grams using a digital scale moving the weight carefully. I was using the smaller weight because my SAE1000e cartridge is 4.8 grams total weight.
Just forget about the balancing and set the correct VTF with an external scale. You should be fine.

I am also using the smaller/lighter GT Counterweight the same way with the digital scale.

Back when I first tried the disengage I thought it was not working. The spring dial gives an upward motion on the tone arm. It is a bit confusing.

[Wozza]

Hi.

Thanks for all your replies.

Looks like my best bet is to speak to Michell.

The reason why I bought the Tecnoweight is because even though I find my P3 has plenty of bass energy, its lacking in bass finesse and resolution. I was hoping the TW was sharpen this up a bit. Using it with the dial set to '0' had no effect on this problem. So, if I can't use the TW as intended (no spring) I'm rather stuck.

Surreptitiously it has made me set up a P5 again I bought a few months ago. Initially I didn't like it but I have just tried it with a tighter fitting O ring counterweight and bizarrely the sound is more to my liking!! So I think I will sell my P3 and keep the P5.

So it looks like I will be using an RB700 from now on. Thing is I don't want to crack the stub off this RB700 only to find I'm in the same situation again.

I use the Techno weight on an RB 700 and it works fine.
Forget about balancing the arm. I NEVER balance it. It is set all the way to 3.5 or past on the dial.
I go from there and set the "vtf" vertical tracking force to my needed 1.8 grams using a digital scale moving the weight carefully. I was using the smaller weight because my SAE1000e cartridge is 4.8 grams total weight.
Just forget about the balancing and set the correct VTF with an external scale. You should be fine.

Can you tell me how close the weight is too the tube??

Thanks

[tomytoons]

I was using the smaller weight for my 4.8 gram cartridge.
It was about 3/8" or 9mm from the main arm tube or pivot housing.