VICKERS MK6B's resto

[colin jones]

I am going to make the race in layer and weld them together as the profile is not something I can do in one piece but as I am able to cut all layers very accurate it will not be a problem as long as I manage the heat during the welding process. When I first saw the top of these tanks, I was amazed how thin the material was not knowing the profile of the turret ring and race as that is where it gets its strength from. The turret is almost as wide as the tank itself.
It really a very good design and a very interesting one to make as well. I had I price of $7k to make each race and a 2 month waiting time from China. Happy to make my own.

[Lynn Eades]

Mike, I have wondered what made it back across the channel as well, but it seems like nothing did.
About 63,500 vehicles were left behind, as I recall. I have no idea of what was sent.

[Mike Cecil]

Good point Lynn, but I was actually wondering about the human toll - sorry if I didn't make that clearer.

But talking of the cost in AFVs, the footage shows a Dragon (?) upside down in a bomb crater. That sudden flip & drop must have come as a shock to the crew.

Mike

[David Herbert]

Originally Posted by Lynn Eades

About 63,500 vehicles were left behind, as I recall. I have no idea of what was sent.

Lynn, Surely that is too high a number ! I have no evidence but I could just about go for 6,350 but even that sounds high when you consider that the BEF was before we were propperly geared up for WW2 and did not have the vast number of American and Canadian trucks that we used for the Normandy landings.

David

[David Herbert]

Originally Posted by colin jones

I am going to make the race in layer and weld them together as the profile is not something I can do in one piece but as I am able to cut all layers very accurate it will not be a problem as long as I manage the heat during the welding process.

Colin, I wonder if you could rely on the bolts that hold the ring to the hull and not actually weld the layers together at all. The turret is not very heavy and the balls are hardly going to prise the layers apart. I am thinking that building the ring in layers should work pretty well. The running surface will need to be relatively smooth and the ends of the segments be aligned but there are enough balls that the surface loading will not require hardening of the running surface (though it would be nice). Actually WW2 proper tank turret rings were soft enough that there were instructions to move the turrets from time to time to prevent indentations forming.

Great work as always.
David

[Lynn Eades]

David, the number of 63,500 is from memory. I will check my book when I get home. The book is called "The Sands of Dunkirk" and I am reasonably sure about the figure. Basically Britian had to start again.
Keep in mind that the Germans had been building up their war materials and that the rest of Europe was in turmoil. Hitler had taken control in Germany in 1933. GB was moving in the same direction production wise.

Mike, my mistake. Sorry.

I await Colin's answer to Douglas's question.

[colin jones]

Doug, I have very successfully used wood saw material for clips on a run of bren gun carrier drivers tool box clips I made a few years ago. I cut the blade on a Guillotine for the shape as they were rectangle pieces. I was able to drill holes in it to rivet it to the doors. I tried to find the thread I did a few years back but couldn't find it. I did use the oxy/act to get some sharp bends and that worked well but you have to bend it slow as not to snap it.
David, there is 220 3/4 ball bearings in each race so it should spin very easy and I don't think I will have a problem at all with wear. the profile also has a small groove in the bottom and top of the bed which I assume is for grease and foreign material to sit. I cant really bolt it all as there is not enough room as you will see when I get a bit further along. The heat wont be too much of an issue although I think it will be about 3-4 layers in total but once I grind them all it should look like a cast ring and this is also new ground for me as I've not done a ball race before. I will keep posting

[colin jones]

Doug, I just found the old thread of the clips I made from a wood saw.

[David Herbert]

Colin,
I had asumed that there were about 40 bolts 'sewing' the ring to the hull as with bigger tanks. That would have been plenty to hold the layers together. In WW2 it was usual for the bolts to be fitted from the top and have slotted, countersunk heads so that they didn't stick up above the ring, nuts on the bottom. Then they started screwing them in from below into tapped holes in the ring. I hope the turret is just free to traverse with just a brake /lock to stop it. If it had geared traverse that is a whole minefield in itself. I will be fascinated to see the detail of how you make the ring as it is quite a challenge to get it spot on.

It might help that in Valentine production they used a device that was suported on a bearing fixed to the tank floor and another above the hull roof but fixed to it. The device was free to rotate on a vertical axis between these bearings which could be adjusted so that the axis was exactly in the centre of the turret ring. There was an electric grinder mounted onto the rotating part that was used to true up the hole that the ring would bolt into. Vickers did have a vertical lathe that would turn a whole tank hull but possibly it was needed for other jobs. This concept might be usefull here ?

David

[colin jones]

Dave, there are not that many bolts holding it down, 16 is what I can find and only 3/8 or possibly 7/16. It does have a geared traverse and you are definitely right another minefield on its own. I have a few ideas for that but cross that bridge in a week or so.

[Douglas Greville]

Colin. Many thanks. Interesting info that will come in handy.
Regards
Doug

Originally Posted by colin jones

Doug, I just found the old thread of the clips I made from a wood saw.

[Jonathan Moore]

Colin,

Amazing work and a joy to follow.

Stunning, truly stunning.

Jonathan