I think one of the mistakes made by myself here is showing the results of the model for situations that are a million miles away from a cast. I don't think so. I found it useful to look at it in that way. I don't think anyone was thinking that was a reflection of what was happening in a real cast, ...

James What I find interesting about this is that the peaks and troughs are out of phase with one another. This was shown in one of Merlin's earlier graphs too. I thought the two would be in phase and therefore if you plotted the average of the two sets of results you would get a straight line. It d...

One difficulty with the SHO, maybe the main one, is to understand that the energy stored in the spring is ... used in facilitating the deceleration of the rod ... Hi Merlin By this, do you mean that you have to use less force to stop the rod? If so, is this the same as the weight in Aitor's experim...

There looks to be a slingshot effect here too that as far as I know we don't use in fly casting (phew!) but I have thought probably is important in surf casting. Of course they use flexible rods there too although they rotate them through a much wider arc than the trebuchet. On Aitor s original exp...

I think the reason why I thought we would get the oscillating effect was that if the spring lengthened and then stayed fixed so that the brick on the spring always lagged behind the other brick, we will have lost something and I am not sure where that something will have gone. To keep everything in...

Aitor, your post 382, so you are saying that the weight will either increase or maintain its acceleration so the spring will lengthen until it reaches maximum acceleration and since it does not reduce acceleration, the length of the spring will never reduce so the weight on the spring will always l...

Hi Aitor, I do think it is relevant to casting which is why it interested me to think about it. I see you get constant force which I doubt you get in a cast, but your experiment takes that variable out which I think is useful :) I do think the spring will stretch and compress alternately as long as...

Well, I hesitate to do this, but I’ve been thinking about it on the train today and it is a Friday afternoon…. I don’t have the apparatus and I don’t have a physics or engineering background, so this is my guess as to what will happen with the weight, the brick and the spring: 1. The weight on the ...