Mk IV male sponsons

[Kevin Hunter]

Is anyone please able to assist? What fixings are used to fasten the sponson roof EK0403 and mid-plate EK0404 to the sponson frame EK0401?
Other parts seem to be a mix of M3x6 button heads and rivets but I can't see any notes in the build manual for these heavy structural parts.
Thanks
Kevin

[Walter Mackinnon]

Hi Kevin,
You need 4x12 cap head, refer to page 23 at the top. I hope this solves the problem for you.

Regards Walter.

[Kevin Hunter]

Ah, yes. That's the problem with only looking at the male sponsons pages 24/25 and not checking other sections
Thanks Walter, great help.
Kevin

[Kevin Hunter]

Fellow Mk IV builders..... sorry to ask for help again. Did anyone else find the 6pdr drums to be a very tight fit in the sponsons? I had to work both drums between the sponson tops and the sub floors - one needed quite a lot of effort so it just doesn't feel right.
The bushes on which the drums sit are proud of the floor but I imagine that's correct. They are flush on the underside so I'm happy they are in correctly.
I know the sponson tops have different part numbers, but are they actually handed and, before I strip them down,do they give more clearance one way around or another?
Thanks
Kevin

[Daniel Scholefield]

The Sponsons should go in without any effort, I didn't have to do any modification or grinding on mine, all my fit issues were with the female set which is why I went with the male ones. I don't think the tops are handed but it's been a while so I might be wrong. Looking at the manual the bush should go inside the 6 pounder drum, not underneath so I am not sure what you mean by it not sitting flush, could that be the issue?

[Kevin Hunter]

Thanks Daniel, but I wonder if we're talking about the same parts?
I don't see how the bush I referred to could go inside the drum, as the hole in the drum is too small and is also threaded to take the pivot bolt. I accept that the drawings are misleading as the bush appears to be inside the 6 pdr drum.

My problem shown below

As it stands there is no way either drum will rotate unless a couple of mm are skimmed from the drum top (allowing for paint also)

Kevin

[Daniel Scholefield]

Kevin, you are right, I shouldn't go off my notoriuosly unreliable memory! I was curious how it fits so I removed the sponson drum so I could see how proud the bush should be for it to clear. The drum came out with no restistance and I had never had to grind anything down, that being said it could be that there is too much 'meat' on the bushes you have. Here is a look at how mine looks:-

[Kevin Hunter]

Once again, thanks Daniel. Your photos are really helpful. The bush in my sponsons certainly protrudes no more than yours ( and as mentioned before is flush beneath the "mid floor" so I'm happy they are in right).

I'm going to try swapping the roof plates - it's possible they are the wrong way around. Watch this space
Kevin

[Kevin Hunter]

Ok, have now established that the male sponson roofs are definitely "handed". As the photo shows, the holes on the 3 outside faces are offcentre such that depending on which way up it goes there is more or less space for the 6pdr drum.

Having swapped my roofs I now have clearance for the drum to rotate freely. However the roof now sits proud of the sponson sides ( see pic) by almost 5mm. I also have a spurious single hole at the right hand end and no idea why.

Previously my roofs were flush with the sponson sides but of course I couldn't fit the drums properly.

Which way round is right?

Thanks
Kevin

[Daniel Scholefield]

Ok, well the bad news is that I think the proper way to fit the roof is with the holes at the upper edge, otherwise the roof will not sit flush and the sponson will not fit to the hull. I think the two vertical holes are meant to line up with the top two holes in the side plate (I tried to verify that on mine but it appears I just glued rivets in them so it is inconclusive).

This of course leaves you with your original problem which is a mystery - if the 'floor' section is bolted in correctly and the bush is no higher than mine why is there not enough clearance? I don't recall anyone else having this issue so I don't think it's a dimension issue with the kit (like the track tensioner trays).

Maybe one of the more accomplished engineers can shed some light, I am just a first time bodger after all

[Steve Stuart]

One of my Sponson's guns was a very tight fit so I shaved a little off the top of the brass bush in the Lathe so that it then fitted in snug, but not tight. I did this to both. So I hope this helps you to follow my solution, it works for me!
Regards Steve