Still working on the Female sponsons - every time I look at my picture collection, I find more things to do !
The WW1 tanks were too wide to be transported on the existing railway network. With Marks I to III this meant that the sponsons needed to be unbolted, transported separately, and then refitted at the destination. An awful job by all accounts, especially given that the sponsons gave the whole tank some structural rigidity so, when they were taken off, the bolt holes went out of alignment .....
For the Mark IV, a system was invented whereby the sponsons could be partially unbolted, and then swung inboard on pivots. This apparently made the job easier, although still a royal pain. I haven't yet studied how this affects the Male sponsons, but I have worked it out for the Females.
Essentially, the Female sponsons were unbolted down the centre line, and then swung in from the centre. This meant that the sponsons were made in two sections, with a plate down the centre line riveted on one side, and bolted on the other. This can be seen on the survivors (Ashford, Lincoln, and Bovington's Mark V**). So there's my pattern - now to recreate it.
My caveat is, though, that this is purely for show ! I'm representing the outside only - the idea of actually making this work is way above my competence (
although not, I suspect, some of the obvious Armortek stars, who I'm simply in awe of. You know who you are).
All that is required is a 1 inch wide strip of metal (I've used aluminium), slightly shorter than the depth of the sponson (to allow for the swing in). On one side this can use the existing 7 holes, so you just need to drill through and rivet.
But the other side only has 5 holes - the top, bottom and centre holes are OK, but you'll need to drill two extra holes equidistant between the centre and the edge. These 5 holes then require hex heads (M3 x 6mm) NOT rivets. The result is:
(original Armortek sponson at top, then my amendments, including the revised periscope and pistol port layout mentioned before)
You'll note that this now makes the sponsons handed. I've checked through all my picture stocks, and believe that the edge with the 7 rivets is always towards the front of the tank, suggesting that the rear section was swung in first. I've only found 3 exceptions to this rule, all of which I think are explainable:
1. Lotte the Beutepanzer (ex-F30 Flaming Fire). The left-hand sponson has the rivets to the rear, differently to the right-hand sponson. There are clear signs of damage around the sponson, with several patches welded on around it. I suspect that the Germans simply sourced a sponson from another captured tank, either not realising that they were handed or not having the stock to care !
2. Presentation tank to Hitchen. This, unusually for a post-War presentation, was clearly a 'fighting' tank, as it has the unditching rails and the mid-1918 red / white stripes. Again, I suspect it was damaged in combat and any old sponson was put on as it was never to be used in service again.
3. The Cologne Mark V Hermaphrodites. There's a story to be told about these ... one day. I've no idea why L Battalion did it, but I guess they just swapped the sponsons round because they could. There's no consistency between which side was Male and which Female.
I think I've done the history side to death, and probably bored you all rigid in the process ! You'll be relieved to hear that I can only think of one more stage with these sponsons before they get painted, and that concerns the top and bottom plates, which need angled straps for the folding mechanism, and a row of rivets around the outside of the top plate. This picture of L52
Lyric is the best I can find ....
All the best,
Chris