Hi All,
I've been studying the plans of the build sequence for the 20mm gun and mount before starting assembly (like all good modelers should ), and I'm thinking some bits are missing.
I suppose (in usage) the gunner could push with his feet to traverse the gun - although I don't think this would be very 'German' - but what about elevation? There's no handwheel or similar, although on the Archive 1944-5 Panzer Wrecks site:
http://www.network54.com/Forum/571595/thread/1184233877/last-1184233877/SdKfz+251-17+Schwebelafette+-+Some+unpublish
there seems to be some sort of motor cycle handlebar arrangement connected to the mount but not replicated in the kit.
If anyone knows of anything I could scratch to mimic these mechanisms I would be very grateful.
TIA
Tom

Tom;

Hi! Hey! I detect another Scwebelaffete "fan"!

You raise a couple of good questions... I think the best place to get answers for the "how was the mount "powered" part would come from that "Lehrfilm" or training film cited in the pics- When I look at the various pics, specially those showing ripped-open -251 where the base of the mount is exposed, and that lead pic showing the fellow hunched down behind the mount, I start to think that those 2 prominent and rather substantial-looking handles on the lower rear OUTSIDE quadrants play a big role... the pedestal of the mount does not show any obvious gearing nor drive mechanism fitted, yet, if there were such thing, say connected to a traverse wheel in the mount, one should see something? Likewise, no evident foot-pedals whereby the gunner might activate such with his feet... I think the mount was traversed with the help of the guy behind and outside the shield.

Would this be effective? Given as this thing was really a ground-fire weapon and probably put together to provide rather close-in fire, a coordinated gunner and assistant could probably traverse this mount sufficiently "tightly" to achieve a general suppressing fire. NOT sniper-grade marksmenship, but "filed fire". The gunner would muscle the mount the small detail increments he desired.

Comment on what looks like weird center-of-gravity... The weapon itself is of course on a cantilevered spring-buffered mount, and I'd bet it was pretty well spring-balanced, at that. So I am guessing its elevation was actually probably pretty easy for a gunner with or using a stout handle-grip instead of an elevation wheel and gear, but... Likewise, the gun-shield, which is conspicuously "complete" around behind the gunner, probably well-balanced the mount and acted as a counter-weight to the protruding gun-barrel and mechanism. From this, this looks to me like it would be relatively easy to hand-traverse - with that outside guy adding some rapid movement muscle as needed (one person can actually effectively swivel a rather large mass / weight around a pivot, if it is balanced... consider if you have ever pushed a car or a floating boat by hand... but mass = momentum and inertia, so overcoming these and keeping control of things would benefit from the outside guy with more leverage!).

Bear in mind also that other, more-massive turrets worked on hand-wheels - the 2cm hanglafette on the sdkfz 222 comes to mind. Point being all of these were actually pretty well balanced and just took a little muscle to move around both quickly and precisely.

Other bits? That travel lock detail... makes some sense, specially if this "turret" really is freely-pivoting and elevating on springs... having it locked down while bouncing along by a simple pin-and-socket device would be ideal! And having that pin controlled by the gunner from within the turret would be the only way I'd want to go...

The odd "bucket" detail still leaves me wondering. As a shell deflector, it seems to make less than good sense, as the hot brassies still go bouncing around the crew compartment, and if the gun were aimed off to the ca 9 - 11 quad, I suspect those would have deflected right onto the driver... But I seriously don't know! I would have thought that the Germans would have attached some sort of catcher-bag there, but...

I must have missed the "bike handle" bit - but from above and my conviction that this thing was entirely man-powered, such a grip would provide a guy a modicum of leverage to move a balanced pivoting mass...

The pics do provide a wealth of detail and I am way glad you posted this thread, as the 251/17 and the 234/ with this mount are in my stack! IF you can see it in the pics, I suppose you should consider fitting a bit in. I know I will!

Cheers!

Bob

Bob,
Glad you found the link useful!
The bike handle thing (if not motor bike, think old fashioned crane operating lever) is visible on pictures 6 (big close up!), 14 and 17 of the link I supplied.
It protrudes forward of the pedestal, under the height of the shield. Maybe a break system operated by the gunner.
It could be the trigger to dis-engage the travel lock (traverse or, the mentioned elevation) lock.
Pic 17 shows the handle/pedestal area.
And, yes, I like vehicles that are adapted especially open topped vehicles.(and strangely enough others used for reccy)
TTFN
Tom

I always presumed that this mounting was 360 degree traverse.
I have my kit assembled up to the hull 'knuckle' and dry fitting the 2cm mount (assembled with actual gun omitted) the seats for gunner and loader hit the ammo storage on either side.
Have I done something wrong; is the kit wrong (somehow) or is this as it should be?



Tom

Tom;

Hi!

Ah.... Errrrr.... Hmmmmm. Well, I don't know!

But here's a guess: Perhaps the gun was really set up to fire within a modest frontal arc - It was very most likely designed to be a ground-fire weapon system (by late war, a single-barrel 2cm gun mount was really of little use against the overwhelming air-power of the Allies, and a Jabo was unlikely to be much deterred by such a modest weapon. On the other hand, such a gun was pretty useful for ground support fire - just as pictured on the Dragon box!). And the generality of the few pics available of these shows these things to be pointing more or less forward, both in use and after being demolished.

The sad but possible alternative is, of course, that the kit has one of those design flaws where the interior or other bits are wrongly-placed and wrongly obstruct the expected movement. Much as you report. I rather (admittedly wishfully so and without real evidence) favor the first spin above - that this system was built limited in traverse.

Cheers!

Bob

It might just be a perspective thing, but looking at a couple of pics on the link I posted. The seats look to be much closer to the pedestal than the kit replicates.
The photo of the modified 234/3 gunner's seat looks like it's nearly touching the pedestal, and 2 photos below that (the side-less 251 photo) the loader's seat looks about half the distance away than the model's seat.
Also, does the pedestal look a lot shorter in this image than the kit part?

Anyway, it's a little too late to change anything serious now so I'll just live with it.
TTFN
Tom

I'm now at the point where the vehicle is virtually complete,base coat painted and ready for camo etc. - except for the gun shield.

If part MB2 (the shield) is naturally aligned with part K37 (surfaces to be CA'ed touching along their relevant contact areas) there is no way for the gunner to get his head anywhere near the sights, in fact, if he's sitting on his seat he'll be looking at the rear face of the shield. Part K37 is fitted as per the instructions.
Anyone know of any 'tweaks' I can employ?

TTFN

Tom