More scratchbuilding fun. Naturally, if the front of the turret is uparmoured with Chobham, then so would the gun shield be. I figured this would be a fairly simple wedge shape, as there is no room for a more internal shield like on the M1. Working out the shape of the side panels proved quite tricky, though, and the hole through the front was only slightly simpler.
Here are the basic parts:
First was the round bit, which will go around the plastic tube I already have sticking out the front of the turret. My father made this for me on his lathe, from some scrap plastic (a bobbin of some kind, I think) that was about the right size of 11 mm diameter. Unfortunately it seems to be polyethylene, which is hard to glue, but I’ve got a pen that will probably allow superglue to stick to it.
After that I built the sides with a bottom plate that you can see on the left in the photo, which was fairly straightforward once I had one side plate the right size and shape. I made the second one by tracing the first on plastic card and cutting it out, which left it a little oversize. I then clamped them both into my modeller’s vice and filed the second part down to match the first.
The angled front plates need a hole trough them for the round part, and this could be quite tricky to get right, because this will be part of an ellipse, not a relatively easy to draw/cut circle. What I ended up doing was draw a front view in Adobe Illustrator: just two rectangles and a circle. I then subtracted the circle from the rectangles, leaving a perfectly circular hole. Then all I had to do was stretch each of the rectangles to the actual height of the plate (real height rather than height in the front view), which also stretched the circle to the right shape and size. Printed them out, cut them from the paper and pasted that to the plastic card to get what you see in the photo.
With the holes cut out, the plates then looked like this:
They still need their edges bevelled so the tube will fit, but I’ll only do that when the glue has set on the pieces now I glued them into the mantlet:
As you can see in the back view, I also added reinforcements from 2 mm square rod, to make sure the pieces stay where they are and won’t come loose when I begin filing out the hole.