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Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 12:44 pm
by 43rdRecceReg
Before, and whilst, fitting the other side to the hull floor you need to bond the first of the rear plates in place. In this instance, it's the one I fitted the towbar to. It has mortise and tenon joints, and would be very awkward to fit later, if the sides were fitted without it... :think:
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Then, I fitted the second (uppermost) rear panel. This is a straight fit, without mortise and tenons, but needs to be held steady while curing with cramps. I also added angled styrene bracing to limit future movement.
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After that, I bonded the lower section of the front three plates in place. I wondered what the holes (one indicated by a red arrow) were for in it, as there's no mention of them in the instructional pdf., nor a picture :problem:
Eventually, I chose to fit the plate this way round because the holes are likely to be needed to adjust the Henntec unit. :)
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When fitting the front panel (2nd in the tree plate setup), I clamped and wedged some bits of styrene (of the correct gap dimensions) between the two plates to keep them from flexing out of line, as the panel was pressed home.
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The inevitable gaps have since been filled in internally, and externally, with Milliput (extra fine). On the external joints, I also simulated stretches of spot welding- though these are not likely to be visible when the tanks upright. Still, it seemed worthwhile. :)
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The back section (especially the towbar) will need a wash and brush up, and general tidying, before it encounters primer.
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Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 1:09 pm
by 43rdRecceReg
Back to the suspension. This is where there's not a lot to go on online. Anyway, this is how I tackled it. The wee brass spring retaining bolts (2.5mm hex heads, 12mm shaft length) were screwed in gently to the undersized holes I'd drilled through the plate sandwich. Using a 2.5mm bolt driver, I carefully used the bolts to cut their own thread. Then unscrewed them slightly to receive the loop/hook of the spring.
Then the arms were slipped into place, and the brass pivots I'd made pushed into place. A final light tap was needed to drift them through the inner panel, and the reinforcing strip that's bonded to it. It's an intentionally tight fit, and that was the result I was aiming for. It fits like a cotter pin. The outer stub of the pivot pin will be secured in place by some Plasto. The idea is that if the springs are not up to the job (and they are an unknown quantity), it won't be too much of a pain removing the suspension arms. :| The springs allow the arms to swing almost horizontal, but any more than that might tip their elasticity range beyond recovery.
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The arm now moves freely, as its captive bushing swivels around the brass rod/axle. I'm being very careful in my choice of terminology, lest any unintentional double entendre opportunities emerge. :lolno:
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The gaps around the brass rod end will be filled with Plasto or Milliput, after the arms are centred perfectly.

I can't do all the arms right now (one is incomplete), and so my next task is to fit the Henntec tensioner unit. One reason not to fit the Glacis plate at this stage (as I discovered with the Cromwell build >:< )
is that it makes fitting the Henntec bits exceedingly difficult. But... it does put a lot of cash in the swearbox... :haha:

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 3:38 pm
by 43rdRecceReg
I had wondered whether it was feasible to put some telescopic dampers/shock absorbers into the plate sandwich, instead of a simple pin and tension spring arrangement.
The Christie suspension in the Comet and Cromwell actually has a telescopic damper configuration between the two plates. In fact, I think the Taigen T34 (also a form of Christie suspension) has that sort of suspension setup. I thought, perhaps, of using the dampers/coiled springs seen on the Pz 111 as an option- or even a set of dampers from the T34.
Taigen Pz 111 suspension dampers
Taigen Pz 111 suspension dampers
Panzer 111 suspension struts.jpeg (58.6 KiB) Viewed 2447 times
Still, the spring and pin setup has the virtue of being very simple, but right now, I don't know how robust it is likely to be with the springs I bought. In fact, although the Cromwell has the springs supplied by CL, it has had little more than a bench run so far, and so I'm not aware of how well the suspension will hold up with those springs.
The T34 suspension can be adapted to mate with the Comet (Ludwig) upper hull. A notable example of that is to be found here (a build by Michael C., using a T34 lower hull and suspension):
viewtopic.php?f=33&t=19362&p=175144&hil ... +c#p175144
Comet by Michael C.
Comet by Michael C.
Michael's Comet.jpg (78.85 KiB) Viewed 2447 times
I believe the finishing touches to this build were applied, with great finesse, by Dean (dgsselkirk). :thumbup:
The original build thread can be found here:
viewtopic.php?f=33&t=17863&p=156432&hil ... +c#p156432

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 3:48 pm
by 43rdRecceReg
The Comet hulk in the background shows diagonal brackets where the suspension units used to sit. (Click to enlarge- not all pics come from Imgur)
Comet back to basics
Comet back to basics

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 4:00 pm
by 43rdRecceReg
Stop press! Just had a massive stroke of luck (as opposed to massive stroke :lolno: )- a package has just arrived from Germany bearing some long-awaited goodies, as well as some parts that were overlooked (but badly needed).
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...and some specials:
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I really like the of the driving headlamps and protective bars (they're from the Crusader listings; but were essentially the same as the ones used on the Comet and Cromwell)
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The headlamp glasses have some extra fine detail, and really recall those old Lucas lamps seen on the 1960s Mini Coopers I used to drive (as well as the more venerable cars with starting handles, runner boards and orange arms for winkers, my Dad used to drive us around in... :D ).

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 4:11 pm
by Ad Lav
The sprockets are really smart, had them on the centurion! Make sure you line both sides up perfectly :)

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 4:12 pm
by tomhugill
Hey Roy,

Amazing work so far! Regarding the suspension, mines stock and has survived some
Heavy usage without issue.

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 7:43 pm
by 43rdRecceReg
tomhugill wrote:Hey Roy,

Amazing work so far! Regarding the suspension, mines stock and has survived some
Heavy usage without issue.
Thanks, Tom, and that's also reassuring. However, I'm not convinced that the springs I bought are as robust as the ones Christian supplied for my Cromwell. While the length is comparable, and the stretch sufficient,
the wire thickness of the ones I bought is probably .3 to .4 mm. But Christian's ones were likely to be .5mm gauge. We'll see. :|
I was surprised to find how hard it is to find the ones he sells. :problem:

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 7:48 pm
by 43rdRecceReg
Ad Lav wrote:The sprockets are really smart, had them on the centurion! Make sure you line both sides up perfectly :)
Thanks, Adam. Yes, I know about the alignment issue (he writes... ruefully). I had to undo one entire side (40 odd bolts or so) of a Cromwell sprocket to realign the two sides. >:< I assumed the sprocket gear wheels would align on any of the tapped holes- but apparently not. :eh:

Re: Comet A34- Ludwig kit

Posted: Mon May 27, 2019 8:26 pm
by Model Builder 4
Very nice Roy, it looks like it's coming along a treat, parts of the build can be very fiddly but the finished result is worth it in the end :thumbup:

Cheers, Lee.