I'm trying to work out what sort of replacement springs a person would need to buy. I'm not sure shortening the spring is the best solution, but it is a solution, if done right. I found a
thread about springs used in guns, and the discussion highlights how complicated the math is.
Apparently, cutting coils off of a spring technically makes the spring stronger, because the strength of the spring is relative to its own length. If it takes
x amount of force to compress a spring to its
solid height, after reducing the
free length of the spring, it will take
more force to compress it to its solid height, because you have less leverage, and you have to compress it further to reach its solid height. I tried to follow the math, but it was difficult.
As best I understand it, if you compress a 10" spring by 4" (10"-4" = 6") you're compressing it by 40%. If you reduce the free length of the spring by 2" (10"-2"= 8") and then compress your cut down spring by 4" (8"-4"), you're compressing it by 50%. In both cases, you're compressing it over the same distance (4"), but the amount of compression involved increases (from 40% to 50%) as you shorten the spring.
However, that's considering the free length vs the
working length. In the toy, the springs aren't at their free length by default, they are at their
installed length, which makes things different - by reducing the number of coils in the spring, while keeping the installed length constant, you are (just as intuition would dictate) reducing the spring's 'strength', and therefore reducing the pressure on the joint when the toy is at rest.
Let's say the installed length is 1.0", and the teeth on the ratchet are 0.1" deep. If the spring's free length is 1.5", the installed length of 1.0" has the spring at 33% compression, and the working length, the length of the spring when the teeth are 'on edge', has the spring at 40% compression. The joint, of course, is under more strain when the teeth are on edge - that's what pushes them into place, and provides resistance to the joint's rotation.
Now, cut the spring down a bit to 1.25". Keeping everything else the same, the spring is now only compressed by 20% when the teeth are together, and 28% when on edge. The joint is under much less strain in both positions, and depending on how heavy Trypticon's upper-body is, he may face-plant. Obviously, if you mess up and cut the free length down to less than the installed length, he will almost definitely be permanently screwed up.
But here's the really weird part that confuses the heck out of me. Leaving the installed length and the working length the same means that, turning the ratchet requires a 0.1" compression from 1.0" to 0.9". Now, for the 1.5" spring, that 0.1" change is a 6.67% change in compression, but for the 1.25" spring, that's an 8% change in compression as the ratchet's teeth move across each other. So, if you cut the spring down, the static compression of spring is decreased, but the
change in compression when the joint turns is increased.
I'm a psychologist, not an engineer, so I have no idea what the implications of that are for the torque placed on those plastic tabs when the leg is turned. I assume that it wouldn't be a problem, but I'm not 100% confident. The other problem is that the spring has 'closed coils' at each end, and cutting a closed coil off one end of the spring may not have the outcome that would be expected; for one thing the cut end of the spring may drag across the plastic like a needle on a record player.
If, hypothetically, anyone decides to replace their springs, rather than shorten them, here are the things I think you need to keep in mind:
Dimensions that must be the same as the vanilla springs used in Trypticon: Interior Diameter - Must be bigger than whatever slips through it.
Outside Diameter - Must be smaller than whatever the spring fits in.
Installed Length - Must be less than the Free Length of the replacement spring.
Working Length - Must be more than the Solid Height of the replacement spring.
Changing these dimensions may screw up the functionality of the toy, or the springs may simply not fit inside the joint.
Dimensions that can be shortened to reduce spring strength:Free Length - Length of the spring outside of the mechanism, with no pressure on it.
Solid Height - Length of the spring outside of the mechanism, when pressed as far as it can go.
Shortening the spring will make it weaker, but if you shorten it past its Installed Length the toy will become floppy. If you shorten it past its Working Length, the spring will no longer function at all.
Variables requiring completely new springs:Wire Material - I think softer metals should be weaker.
Wire Diameter - Thinner wire will be weaker.
I don't know how a thinner/softer spring will hold up over time - if the toy is stored/displayed with the springs compressed to their working length, the springs may need to be replaced again in the future.
. I also don't wish to have to open things up and fart around with parts, too much money is involved for me to have to do that. There may be those who may enjoy this or don't mind but not me.
can help rectify things it pains me to say that I will not be getting Trypticon...'nuff said! 
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