Here is the current table of kg-cm cantilever force for tower HS and HSFs mounted in a tower chassis. The weight can be the specification or measured (m*) including K8 mounting hardware. The center of gravity is determined by suspending the HS by a wire or string until the mounting base is perfectly vertical. Once the CG is found, the distance from the base to the CG in cm is measured. Usually a right-angle heat pipe simplifies this but in the case of the Thermaltake Big Typhoon CG determination may be more difficult.

A 4.56kg-cm rating is equivalent to hanging a 456g HS on a wall - or mobo in a tower case - with a 10cm (4") lever arm. Smaller numbers are better.

4.56kg-cm Thermaltake Sonic Tower 691g(m*) 6.6cm, no fan
3.99kg-cm Scythe Ninja = 665g 6cm, no fan
3.94kg-cm Thermalright HR-01 525g 7.5cm, no fan
3.18kg-cm Zalman CNSP 9500 530g 6cm, with fan
3.12kg-cm Scythe Shogun 691g(m*) 5.4cm, no fan
2.79kg-cm Arctic Cooling Freezer 64 472g(m*) 5.9cm, with fan
1.58kg-cm Scythe NCU-2000 478g(m*) 3.3cm, no fan

Could some of you other readers add to this table? I'm really interested in the numbers for the Big Typhoon, but not interested enough to buy one!

nice

This is very interesting.
thanks.

Here comes a monster (not a BigTyp, sorry)

5.97 kg cm Thermalright Ultra-120 733g(m*) 7.9cm, no fan

I cant say that I am very interested, except on the basis of accuracy. Did you use math to produce these numbers and if so how, or somehow find out the specifics for each heatsink.

If you look at the weight balance (on its side) of a Ninja, the bottom is a fair bit heavier than the top so the ballance point has shifted downards towards the attachment point, therefore the leverage is less. I am no math genius, I would just like to know how you did your sums.


Andy

You do the measuring as stated in the first post, then you find the moment M = m * B.

Since it's a mass we are measuring and not a force, it would be more correct to do m*B*g, and end up with something like:

M = (0.733 kg)(0.079 m)(9.809 m/s^2) = 0.568 Nm

but g is a constant, and it doesn't make any difference for our purposes.

Ahhh...... So you are doing the math with the centre of gravity included, I missed the "CG" part before, sorry.

Here is a thought for you, you include the K8 mounting bracket weight, but have you measured the 775 weight from the other side of the board where the actual pressure points are, and likewise have you measured the pressure points from the reverse side of the board for all sockets, and the surface area of the pressure on the PCB, and far more importantly the pressure to the plastic mounting points, taking ito accout the breaking points of the plastic.

However its not everything, just what pressure are the mounting clips/screws/etc are putting onto the mounting socket, that will make as much difference to the heatsink taking a plunge during transportation as the cantilever weight itself as the clips will be under pressure, and then add the cantilever force and then add a speed bump/pothole and watch 0.5 KG bounce around your case.

Come on guys a lot of work to do still


Andy

PS: Not taking the piss, its rather interesting really and I would like to know more on the subject.

I would have sworn I just heard somebody volunteer...