2023 new build Jagdpanther part 8

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Hello All. So, here we are in Normandy, June 6th and it's the 79th anniversary of D-Day or, as they call it in France, Jour-J.

Progress on the JP has been a bit sporadic over the past few months but now there is news to impart so here goes.

As described in Part 7 of this log, I'd acquired the gun elevation mechanism from Armortek and decided to use a heavy duty servo for slewing the barrel through its modest 22 degree arc of swivel. Looking through e-Bay, Amazon and various online model shops, I eventually chose a 35kg force, metal geared and aluminium bodied digital servo from Amazon France for the princely sum of 9 Euros. Prices from other suppliers for exactly the same model ranged from 3 to 5 times more! At the same time, I ordered a DC to DC converter to step down the drive battery voltage to 6 volts to feed the receiver and Tamiya DMD sound unit. This was only 8 Euros from Amazon so I was a more than happy bunny.

The delivery arrived on time 3 days later and after some design thought, a mounting bracket was cut from 50x50 x 3 mm thick steel angle. The servo mounting holes were drilled and tapped M2.5, the servo fitted using its vibration absorbing rubber grommets and steel inserts then the whole shebang bolted onto the gun lower pivot block using the Armortek holes provided for their own geared motor system. The factory brass pivot spindle was fitted to the slewing bracket, a pushrod made from M4 studding, a Rose joint and clevis end, the aluminium servo arm drilled and tapped from M3 to M4, the arm position selected then secured to the splined output with screw and pinch bolt.

The original plan was to use the transmitter left hand stick sideways movement to control the slew but, as this stick was spring loaded, it would mean having to maintain finger pressure to slew the barrel to any required position. The trim switch on this stick did not quite provide enough movement to be an effective way of moving the gun – even with travel rates, direction and sub trim adjustments set in that channel's program menu. Therefore, I opted to use the rotary trim knob (channel eight) on top of the transmitter – normally used for helicopter operation. Travel and percentage rates were programmed into that channel's menu so that twisting the knob provided left and right slew but limited so that the Saukopf wouldn't clonk against the mantlet casting. And it worked fine along with the Armortek geared motor elevation system.

The bare metal servo slew bracket was then removed, fettled, sand blasted, primed and painted then fitted for good. So before I took the gun unit off its wooden setting up jig to fit to the hull for the last time, I decided to get in some more driving time to check things over as any tweaks would be a damn sight easier without the hulking great gun in the way. Whizzing around the lounge and through the patio doors was fine but when it reached our loose gravel drive performance tailed off and turns became difficult – not helped by loose pebbles trying to block the tracks and wheels (scale size would equate to between 4 and 7 inches diameter!). And turning ability on the grass was abysmal – it just kept running out of power.

With a freshly charged battery, it was still the same. And the solution? Up the power to 24 volts from the current 12. Which was an obvious move as I'd just discovered that my e-bike/scooter motors were in fact 24 volt units. In the house on our polished tile floors, 12 volts were more than enough but the added resistance of exterior surfaces proved just too much except in straight line running.

A quick trip to our local garden machinery centre resulted in the purchase of an identical size 18 Amp hour gel battery for roughly the same price as the first one I'd sourced online from Germany. This solved the problem and it now tackles all terrains with ease – but it doesn't like loose gravel so I'm staying off these types of surface. Especially as one stone got wedged, broke two track links and bent their pins. Ho hum, one lives and learns...

The second battery is located just behind the speed controllers in the fighting compartment and the small DC converter wired into 24 volts (it can handle up to 40) then via the switch panel to the DMD controller.

You'll see from the photos the main battery master switch, a toggle switch for the converter and a standard receiver switch mounted just below and accessed from the rear loading hatch.

So now it's just a tidy up and looming of the inner wiring, re-fitment of the gun and mechanism, paint touch up, final detailing and weathering.

More to follow including (hopefully!) some Youtube video.

As always, just click on to the pics to view full size.

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First of the promised photos

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The promised photos...

[Marco Peter]

I have seen your work of love in the flesh: really, really nice job!

[graham pipe]

Hey, thanks Marco for the kind words. Was great to meet you and Riny when you recently visited Normandy. Such a shame wife and I couldn't make it to Militracks this year - looked like an amazing show with lovely weather. Next year for definite!!

Keep on tanking!

G