Is it best to remove the whole tonearm when changing cartridges?

[hal55]

I have a vintage Decca London International tonearm and a new cartridge, probably a Denon 110, is scheduled to go in next month. I'm not ham fisted, but I'm not skilled in the art of switching cartridges over either. The Ortofon Omega in the arm is the first one I've ever installed and the arm hadn't been fitted at that time. I'm concerned about damaging the unipivot bearing having heard about arms that have had terminal damage from cartridge swaps.
Am I worrying about nothing? Taking the arm out would be a pain (I'll have to plug the holes in order to refix the screws) but if thats the safest I'll do it that way.

Hal55

[YNWaN]

The answer is that it all depends:

It depends on how much torque you intend to use to fit the new cartridge. I suspect the answer to this is 'not very much', unless you are intending to use stainless steel nuts and screws. I don't think the headshell of the arm would allow you to use a lot of torque.

A lot of the bearing damage stories are really about ham fisted dealers and owners and are often more about the oil in the ball-race bearings drying out than the bearings actually being damaged.

[Jagged24]

I have swapped carts for several years on several different arms (none a unipivot, mind) without removing the arm, and have not encountered a problem so far.

I agree with YnWaN that using only gentle torque on the headshell screws is vital. To this, let me add that it would be advisable to isolate the bearing as much as possible from torque applied at the headshell, by steadying the tonearm whilst turning the headshell screws.

[YNWaN]

I use a unipivot myself, but in that case the arm wand can easily be removed and this makes changing the cartridge very easy.

To be clear, I would personally choose to use stainless steel mounting hardware and tighten the cartridge up very tight. However, this is only appropriate if a/the body of the cartridge will allow it and, b/ the headshell will allow it. Finally, c/ one isn't terminally ham fisted - which means that at least 50% of all dealers should not even think about it (and the remaining 50% should think twice).

[hal55]

Seems like I'll have a gentle try with the arm in place, and if that isn't working I'll remove it.
Sounds like a plan,

Hal55

[DSJR]

If it's a Linn arm, especially a now old one, I'd suggest removing the arm and cradling the bearing end in your lap while tightening the cartridge bolts with long-nosed pliers and NEW Allen key, levering with the short end, NOT the long one as I used to, sometimes breaking cantilevers in the process as my thumb was too close

Rega RB300 types are MUCH more solidly put together (for good or for bad) and pretty well immune to excessive torque at the headshell end, the 250 series less so since loc-tite is a feature of locking up the brass (rather than hand toleranced stainless steel) bearing parts.

Since many cartridges still use plastic bodies, you won't need to tighten everything up until it all but breaks, so take care - finger tight plus a little more is usually enough unless it's a metal bodied Linn MC cartridge of old and even then, wooden tonearm mounting plates could get stressed if too much force is used fitting a pickup with arm in situ. Just use some careful common sense, especially if the arm and cartridge are classic used items with no spares backup, such as Ittoks etc.....

[YNWaN]

Yep, if the cartridge or headshell is made from wood or plastic you must not use a lot of force to tighten the cartridge.

The only negative I would say regarding the Rega headshell is that, because it is cast, it's quite a bit softer than one milled from billet

[stewartwen]

The International was fitted with a removable headshell. All you have to do is to hold the arm pivot firmly then tug the headshell and it will come off!
S