To help with those who are playing with such ideas as some shown the stand discussions here is some design calculations. (I'm sure we can get some checking of my math too...)

This goes with this image

Basic premise is as follows. Each force applied to the pole can be broken down into components that act parallel to the ground (perpendicular to the pole) and parallel to the pole.

Now the calculations!!!

We start with the weight/tension on the hammock line (Hammock Line Tension). The vertical component of this (HLV) has to be half the weight of the person (plus the hammock) otherwise they fall. Lets make that half weight, W. The angle from horizontal of the suspension line is going to be A.

HLV = W

HLH = (HLV/sin A)*cos A = (W/sin A)*cos A = W/tan A

Ok now we want to know the guy line forces, for this we have to assume there is a pre-tension on the top line of TL.

GLH = HLH + TL = (W/tan A) + TL

This has to be true other wise the pole is falling one way or the other. Also you'll note that when the weight is zero then, GLH = TL (that is TL is just the pre-tension in the top line before anyone gets in the hammock, and that we want this to be as small as possible to reduce our stresses on the system.)

The tension on an imaginary (single) guy line coudl eb written as GLT. This GLT is found from the value of GLH.

GLT = GLH/cos B = ((W/tan A) + TL)/cos B

from this we get the vertical portion.

GLV = GLT *sin B =(((W/tan A) + TL)/cos B)*sin B

= ((W/tan A) + TL)*tan B

The compression force on your pole is

Compression force = GLV + HLV

= W + (((W/tan A) + TL)*tan B)

Moving on to tension in the guy lines as shown in the top view. Here we have the half angle between the guy lines shown as C (in the plane of the lines). And we have the tension they have to exert together as GLH... individually that component is going to be called HGLT.

HGLT = GLH/2 = ((W/tan A) + TL)/2

The tension in each guy line is:

TGuyline=(HGLT/cos B)/cos C = ((W/tan A) + TL))/cos B /cos C.

I'll follow-up with a second post where I do an example with numbers.

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