Unbuckling a belt with telekinesis

[Crystalline_Entity]

I'm trying to work out what level of telekinesis you'd need to unbuckle an opponent's belt (containing a scabbard and large knife, say a total weight of 1.5 lbs). If it's important, this is for Sorcery, but I think the question is a generic one.

Originally Posted by Basic p.92

You can move any object you have strength enough to lift, at a Move equal to your TK level, modified as usual for encumbrance level

Using Telekinesis 1, I've got a basic lift of 0.2 lbs, the belt and dagger come at extra-heavy encumbrance (up to 2 lbs), which modifies move by a factor of 0.2... but Move cannot be less than 1 (as per B17), so there's no penalty to it, so I can move up to 2 lbs at 1yd/second; that doesn't really help with actually unbuckling the belt though.

So I then thought I'd need the lifting rules on B353, which say a two-handed lift can lift 8xBL but takes four seconds, which is just enough to lift 1.5 lbs with Telekinesis 1. Ideally this would take less time so the opponent doesn't have chance to work out what's happening, so I guess I'd need a higher level of Telekinesis to do it in one or two seconds. This is just the time to lift it, rather than actually unbuckle the belt which would take two or three more seconds.

I'm slightly confused which rules apply in this situation. If someone could explain what level of telekinesis I need to manipulate (rather than carry, or lift, or throw) a given weight without a time penalty, that'd be great! Thanks!

[weby]

There is no official rule on that, but with a normal style belt you need a bit of force pulling out at the end of the belt while you use slip it out. But the force normally needed is really low. On a older belts before buckles people usually just tied the belt with a knot, most knots do not require much to pull open, but some people do really tight knots...

So in reality it depends on the GM view, for the buckle type belt ST 1 should be enough in almost all cases, so I as GM would likely roll 1d-5(min 1) as the required ST(or maybe for big complex buckles 1d-4).

For the knots I would require on average bit more, but still most are easy so rolling 1d-4(min 1) for required ST would seem reasonable(or maybe 1d-3 for strong dumb people doing the knot).

But that is because I want to have variable challenges. In reality ST 1 should in any case be enough for most cases.

[Sam Baughn]

This seems like it could be tested in a fairly simple experiment. You basically need to know what force is needed to overcome the friction of a belt in a buckle. So just hang a belt off a tree branch, beam or a friend's arm. Then buckle it without the pin going through a hole, attach some kind of bag or something and load the bag with weight until it pulls the belt through.

[johndallman]

There's also the question of how much tension the belt is under from the wearer's body. For fat people, this can be significant, if I'm at all representative.

[edk926]

This kind of leads to all sorts of questions about using Telekinesis for things other than simply lifting up objects lying around.

Like for example, what level would be required to turn a knob or handle and open a typical wooden door?

[weby]

Originally Posted by edk926

Like for example, what level would be required to turn a knob or handle and open a typical wooden door?

There is a huge variation depending on how stuck the door is.

Given that some doors require effort from adults the upper end of the requirement is pretty high.

[Crystalline_Entity]

It's almost like I need telekinesis to exert a certain amount of force, though it's stated in terms of weight (mass) and a velocity in Basic. I'd be tempted to just assume that you can exert (Basic Lift) force in Earth gravity.

I like the idea of actually doing an experiment to see how much force is required! I might try later, though johndallman raises a good point about it depending on how much tension it's under.

I wonder if you could work out a minimum ST by seeing if a common animal could do it (if they had fine manipulators), e.g. could a cat with ST 4 open a door handle?

[evileeyore]

Originally Posted by Crystalline_Entity

I wonder if you could work out a minimum ST by seeing if a common animal could do it (if they had fine manipulators), e.g. could a cat with ST 4 open a door handle?

Had a cat that could open this type of door handle (the dogs could as well, which is eventually why it got changed).

Though the cat used his entire body weight, so not sure 'cat ST' was particularly relevant.

[smurf]

There's no hard and fast rules because you simply cannot write the rules for everything.

Judging by my children's development.

ST1 - can push a button
ST2 - can flick a switch
ST3 - activate a 'hand size' lever
ST4 - turn a tap on and off
ST5 - undo a belt system.

Of course this is completely arbitrary but it is just thinking of the force required to operate any of these things.

[acrosome]

Originally Posted by Sam Baughn

This seems like it could be tested in a fairly simple experiment. You basically need to know what force is needed to overcome the friction of a belt in a buckle. So just hang a belt off a tree branch, beam or a friend's arm. Then buckle it without the pin going through a hole, attach some kind of bag or something and load the bag with weight until it pulls the belt through.

How much weight is hanging from the belt would obviously affect this as well. Weight would result in more tension on the belt, which would need to be overcome. I might just hand wave it as "however much weight is hanging from the belt, minimum ST1".

If you assume that whatever is hanging on the belt is not accelerating (which is very reasonable) then tension simplifies to:

T = mg

where m is mass in kg and g is 9.8m/s/s. So 5kg is about 49N. I don't know what ST that equates to. And I don't know how having the belt horizontal might affect this. Physics 101 was a LONG time ago, and I'm too lazy to look it up. Someone here will spit it right out, though.