Dear all
I have now reached the point in the model where I need to make the torsos (of the life-size models) strong enough. After considering many options and ideas, I have come up with a three method system, greatly inspired and influenced by the comments people kindly posted on this thread (many thanks!).
First up I have decided to to strengthen the whole of the torso by triple layering it (in a similar way as the other parts of the model).
When I considered the effect of adding arms to the torso I think what will happen will be the arms will want to move down (in the direction of the yellow arrows in the photo below) which will in turn want to push the sides of the torso in (as shown by the red arrows) and also the front and back of the torso out (as shown in the second photo)
I do not think the triple layered wall of the torso will be strong enough to stop this so intend to add vertical and horizontal struts (like a bird cage or like on the inside of the statue of liberty). These struts will be multiple layers of paper glued to the inside of the torso (as done similar on the knees and thighs)
There is also the addition "action" of the life support pack on the torso. I think this will also pull and push on the torso as indicated by the red arrows on the photo below
I have not yet decided how to attach the life support pack to the torso (but have a couple of ideas). However all things considered the third level of strengthening is adding removable "bars" of multilayered card (so acting like bracing) at the points where the torso is being squeezed (so the bards would be in compression). If figure if you can stop all the points where the torso is being squeezed then it follows that the torso will not be able to bow out either (since if one bit bows out another bit must bow in).
The reason for going for stopping the "squeeze" point is two fold. First is laminated card is very strong at taking compression. Second is I need to have "access" in side the torso to assemble and disassemble the model, so cannot have any of the bracing permanently fixed to the torso. Thus the bars will not be able to be in tension (so cannot directly stop bowing out).
And if all that doesn't work...
Anyway, the first thing to do is to triple layer the torso. That is an awful lot of gluing. I have decided that I could not face doing a second torso after completing one, so I have split the layering into three stages. I will do each stage for both torsos before moving onto the next stage.
Stage one is to do the neck and shoulders
Stage two is to do the waist and sides
And stage three is to do the front and back
After this is done the whole process has to be repeated!.
I think this is going to be a bit of a make or break moment for the model. It really does need to be strong enough without being too heavy or to fragile. Well I have a plan and there is only one way to find out if it is going to work, though this is going to take quite a while to do, so a while before I know if the plan is any good.
So it is time to start "The Big Glue".
Regards and take care
Kevin