How to (not) fit the roof.

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Adrian Harris
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How to (not) fit the roof.

Post by Adrian Harris » Mon Jun 19, 2017 3:48 pm

From the pictures I have gathered, it seems there are a number of options of how to leave the roof plate (EK0127) remoavble.

Method 1: Attach the angles (EK0126) to the roof plate (EK0127), as Steve has done.
Method 2: Attach the angles to the hull side bars (EK0130), as Chris and Daniel have done.

Method 1 means the roof plate has more rigidity when off the tank, but is only supported at the ends when in place. Method 2 means the roof is fully supported when on the tank but quite flibby and at risk of bending, and hence losing its shape and possibly paint, when being removed and refitted.

My current plan is to use Method 1, but with the following changes:

1) Counter bore the holes in the side bars (EK0130), so that the nuts are flush with the inside face, and hence don't impinge on the angles when the roof is in place - I'm not using rivets.
2) Use some longer bolts in every third hole, so that the inside end of the bolt sticks proud of the side bars.
3) Cut the angles so that every third hole is a fan shape, such that when the roof is in place, the enlarged holes engage with the ends of the longer screws and provide some support to the roof when in place.

Does that sound plausible, or too wacky ? Is there something in the subsequent build or operation which is likely to scupper this plan ?

Adrian.
R.I.P Margaret I.L.Y

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Adrian Harris
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Re: How to (not) fit the roof.

Post by Adrian Harris » Mon Jun 19, 2017 4:37 pm

(Apologies to be thinking 'out loud')

Plan C:

Use Method 2 as above but fit two lengths of aluminium bar along the length of the underside of the roof, taking the lines of the outer rivets in the section with the rear house, then it is supported when on the tank and stiffened when detached.

I will need to drill out the angles though, so that the nuts on the underside of the roof don't impinge and keep it from sitting at the right height.

Adrian.
R.I.P Margaret I.L.Y

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Chris Hall
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Re: How to (not) fit the roof.

Post by Chris Hall » Mon Jun 19, 2017 7:39 pm

Adrian -

If you're worrying about the rigidity of the roof, you're certainly cracking on .... :)

I think you're over-complicating it, though. I'd certainly recommend following the instructions, and fit the EKO126 strips with long bolts through EKO130 and the inner frame. That way the roof is supported on all 4 sides. I certainly haven't noticed any 'flibbyness' - all the strips going across it, the EKO225 'rear house' and the EKO639 exhaust system help to keep it pretty rigid.

There is an issue, though, with keeping the roof down. I came up with a pragmatic solution (OK, I probably cheated :wink:) by gluing rivets into all the holes along the long sides of the roof and them grinding them flat underneath. So my roof just sits on the supports, rather than bolting through in any way. The roof is held down quite securely by the EKO647 brackets between the roof and the unditching rails - once in place (Steve holds them in with magnets, but I just rely on pressure) I've never had them shake loose, even going over that hill at Tankfest last year, and Denny's knife edge.

Taking the roof off is then a simple matter, to get to all the gubbins inside. The only thing you need to remember is that the exhaust pipe will need to be removeable / slideable, which is a bit more of an issue if you're fitting a smoker (I haven't).

Hope that makes sense ! Happy to give you a 'guided tour' at the weekend (when I've got another technical issue to discuss with you - he said, mysteriously).

All the best,

Chris
Mark IV's #50 (Liesel) and #30 (Flaming Fire II)
Morris Quad #34, limber and 25-pdr
M3 Lee on the way !

Steve Stuart
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Re: How to (not) fit the roof.

Post by Steve Stuart » Mon Jun 19, 2017 7:49 pm

Just for reference here are two pictures of my roof:
DSCN0211.JPG
The sides
DSCN0218.JPG
The Top
The Angle pieces give enough rigidity, but also provide flexibility so the Roof wedges in securely and hope fully gives a certain amount of stiffness to the structure.
We look forward to more progress reports!
Steve

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Chris Hall
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Re: How to (not) fit the roof.

Post by Chris Hall » Mon Jun 19, 2017 8:59 pm

So THAT's how you did it ! Looks good to me, but a bit above my pay grade ....
Mark IV's #50 (Liesel) and #30 (Flaming Fire II)
Morris Quad #34, limber and 25-pdr
M3 Lee on the way !

Oliver Brüninghaus
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Re: How to (not) fit the roof.

Post by Oliver Brüninghaus » Mon Jun 19, 2017 10:14 pm

Hi Adrian,

I was a little bit lazy, followed your method 2 and glued six rectangular rivets into the roof with approx. 2,5 mm dia.
These pins fit into suitable holes of EK0126
I though that the roof needs no structural reinforcement.
Roof1.jpg
pin
Roof4.jpg
pin fits
The exhaust pipe is held into a bracket covered unter EK0637
I positioned the smoker in the rear between the two drives and connected it directly to a new plumbing on the roof.
bracket.jpg
bracket for the exhaust pipe
Plumbing.jpg
shortcut for smoke




regards Oliver





Roof3.jpg
roof in total
Last edited by Oliver Brüninghaus on Thu Jun 22, 2017 9:43 am, edited 1 time in total.

Daniel Scholefield
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Re: How to (not) fit the roof.

Post by Daniel Scholefield » Mon Jun 19, 2017 10:26 pm

I can't add any engineering mojo here, I went with the instructions and can only comment that the roof is rigid enough with the cross strips and the exhaust housing providing support. As for securing the 'lid' I used magnets for hold. On top of that the magnetised supports for the rails serve to jam the roof in place.
Mark IV No. 35 aka. L9 Lightning III

sean kerambrun
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Re: How to (not) fit the roof.

Post by sean kerambrun » Tue Jun 20, 2017 1:07 am

Thanks for all the tips and tricks guys.. I hope to start building mine in the second half of this year.


Cheers

Sean

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