Armour Dreams

[Jonathan Moore]

The original unit rotates the turret 4 degrees for every turn of the handle, so that's 90 turns to rotate the turret through 360 degrees, which I find quite hard to believe. I would have thought that there was a fine and course setting but I can't find any evidence of this, however I have read that the gearbox could be disengaged from the turret ring so that the turret could be rotated manually by hand. The original turret ring gearing would have been quite a precise component but of course mine has been fabricated, so I am trying to compensate for this by allowing the gear that meshes with the turret ring gear to have a certain amount of horizontal float. To this end, the internal gears are housed in a frame that rotates around the small forward gear shaft bearings, at the opposite end of the frame will be a spring, that puts pressure onto the frame, thus forcing the final gear and the turret ring gear together, I hope.

It's early days but I think that it will work.



Jon

[Jonathan Moore]

Evening All,

Things are progressing steadily in the right direction but not as quickly as I would desire. I attached the light and the power plug in the turret, a small job but another one off of the list and I have been making the components for the turret rotation gearbox.

[Jonathan Moore]

The gear box now has it's attachment brackets welded on.
I assembled the gearbox tonight, just to see how it all fitted, it's surprising how many parts there are and this isn't all of them.
It all appears to fit ok, now I just have to machine all the key ways and make the rotation wheel, if only it were that simple.



Jon

[Jonathan Moore]

Evening All,

At last I have finished the turret rotation gearbox, almost. It turned out to be quite complex but that was entirely due to me being too fussy.

I think the turret gearbox had*three settings, fine, course and hand, by which I mean that you can rotate it by pulling it around, all three would be too*complex for my little brain, so I decided just to incorporate two, hand and fine.**when the lever is in the vertical position the gearbox is in hand and when the lever is push forward or backwards the gearbox is in fine.

** *

**

[Jonathan Moore]

While*I was in the process*of deciding how to manufacture the rest of the components*it occurred to me that when one is concentrating on a target or having coffee, having to hold*the lever down until the gearbox internals*meshed, would be slightly inconvenient.*Therefore I*designed the gearbox internals*in such a way that once the lever is pushed forwards or backwards it locks in place,*leaving the operators hands free. *Inside the gearbox there is a keyed dog*that moves vertically on the main shaft, when*the lever is in the vertical position the*keyed*dog is in it's upper position and the turret can be rotated by hand but when the* lever is pushed forward/backwards the dog is lowered,*the keys can mesh with slots in*the large toothed gear and the turret is therefore connected to the hand wheel thus*being in fine mode.* Obviously trying to get everything*in exactly the right position for the keys and slots to mesh every time would be impossible, so to over come this*I decided to spring*load*the plate containing the keyed dog. If the lever is pushed forward or backward it*locks in position, the plate containing the keyed dog is lowered and being spring loaded, if the keys and slots do not line up,*the springs compress.*When the hand wheel is rotated and the *keys and slots line up, the pressure of the springs*force*the keys into the slots and from then on the turret is*rotated using the*hand wheel.

As clear as mud*but trying to work out how to word it was more difficult than actually making the damn thing, me thinks



Jon

[Jonathan Moore]

Evening All,

Continuing with turret gearbox, the next item that I needed to make was the handwheel. Not quite as simple as around disc as it contains a remote trigger for the MG34. It would have been a casting but as I don't have that option, I fabricated it.
It started life as a flat piece of 10mm thick steel plate which I cut, turned and then added the relevant bosses.

[Jonathan Moore]

A quick grind with a burr and a shot blast made it look something like the original.
Then the wall of the bosses needed to be machine away so that the two are connected as when it is finished a pivoted arm fits in the channel and a slot for a drive key needed machining into the opposite side of the center boss .
The handle obviously contains the trigger mechanism, I made the outer housing from separate bits of 3mm plate welded together and then I ground the outer profile to shape.