Borrowed from a camping site:
THE ANATOMY OF AN ANGLED / DOG-LEG PEG.
Hi all..
I thought it interesting to discuss what I know about the common-or-garden angled tent peg..
I posted this at the other camping place, and got some good feedback, I think it’s of value to share here at this campfire as well...
You be the judge & let me know....
At one stage in my not-too-illustrious career, I worked in the spring industry, and the company actually made tent pegs, so I kinda pinned me ears back, rolled up my sleeves, took out my notebook and learnt a wee bit
See, there is actually quite a lot going on behind this seemingly Incongruous piece of equipment that we all just hit into the ground without a second thought....
But without getting into the technicalities (which you can google if you want), just believe me with the following,
Just accept.......... Shock force is greater than a steady pulling force by something like a factor of 4 and waaaay more destructive...
From the sketch above, there are three main components to the peg... The leaver, the spring and the anchor.
THE SPRING
Why have a spring? Well the spring converts most of the damaging shock force, created by buffeting winds on the canvas, into a constant pulling force and reduces the effect of the force on the peg.
WHAT IS THIS EFFECT?
The result of shock force is that the peg compacts the ground in front of the wire, thereby increasing the hole, and the peg becomes loose and comes out of it's hole... OR... It simply yanks the peg out the ground. (When this happens, there may also be another factor, IE the length of the anchor portion is too short for the force).
So the spring is a very important mechanical component of an angled peg
Now it's quite possible that the spring can be stretched beyond it's limit of elasticity. When this happens the spring effect is of no value as it will just continue to stretch open and in-effect what you have is a solid peg...
But never fear, springs can be easily rehabilitated by pre-heating an oven to 240 deg, then putting the pegs into the oven for 1/2H then allowing them to cool off in the air...
Don't quench them. Also once the oven indicates 240, let it first go for a while... The historesis of an ovens thermostat is horrific and you need that to settle down first. The temperature is quite important in this process...
THE LEAVER
For a given wire diameter, the longer the leaver section, the softer the spring, So it stands to reason that a thicker wire, with a longer leaver will have the same effect as a thinner wire with a shorter leaver.. (Remeber this when purchasing a peg).
THE ANCHOR
First up, the shape of the peg has the outcome of transferring all the force to the point of the anchor point, which would be the deepest place in the ground... Quite nifty..
The length of the anchor portion is what matters... The longer it is the stronger the peg, but it won't help trying to hit a long thin peg in as it would just bend, so the longer it is the thicker the wire needs to be... So that's what determines the wire thickness... For all intense and purposes there are 2 factors related to the wire thickness... (1) The strength for hitting it into the ground and (2) the stiffness of the spring effect (thicker wire stiffer / thinner wire softer)
HITTING THE PEG INTO THE GROUND
This is KEY.....
Angled too much up and you lose the effect of the spring, progressively more and more until the leaver portion is at the same angle as the rope and you have a solid peg
Angled too much down and the front of the leaver comes into contact with the ground, forcing the spring portion open, which if exacerbated will actually pull the anchor portion out of the ground, and the peg is in-effective.... Play around with this ....
That's why, with the better quality pegs the hook of the peg is bent a bit upwards so that when the leaver portion is in contact with the ground it does not add to this effect.....
