1/16 Pz2 F - WIP

[ziddan]

So ive derailed myself from the Opel Maultier project.

Figured i wanted a tank, might be shooting myself in the foot with a small one but we shall see, i hadnt realized that 1/16 is a far more common scale for this stuff so decided to fit this design to that instead of 1/10 as i did with the Kubelwagen and Maultier (might rework those to 1/16 later on).

Initially i bought the Pz2F files available over on Cults3d and while the finished example looks excellent i wasnt in love with how the files are laid out, some of the mechanics (like exposed springs made from safety pins on the bottom, swing arms on large threaded screws, etc) and instead decided to go my own way.

Im not sure where i found the files i started from, i went on a binge downloading every Pz2F i could find and then going through the files to see what looked like the best starting point for a printable version.

The one i settled on came in a bunch of .obj files, they look like they were initially exported from War Thunder but someone had started reworking them to make them printable, did a great job mostly but the way i got the files they were somewhat messed up, lots of separate surfaces and overlapped vertices.

I started with sorting them out into which parts they should be and then joining them together.

What ive initially done has been to add in some random surface details and then started rework the suspension, the files had the start of provision for an internal coil spring for each of the swing arm, part of the design is good but the part transferring the motion from the external swing arm to the internal coil spring cant be assembled as it was.

It also had the dummy leaf springs moving with the swing arms so ive separated those, made the leaf springs static, added extra bracing to eliminate possible sideways wobble of the swing arm that would come from using only one point of contact for the pivot axle.

Right now im doing a test print of the isolated reworked design for the swing arm mechanic, i think it should work but i will be able to assemble it in about half an hour.

[jarndice]

When you do your research on the PZ2 you will discover that what would appear to be every other month the Suspension was removed and replaced with a different system,(An exaggeration) but it did have at least 4 different suspension redesigns
It really was a most unsatisfactory base for a tank and the suspension experiment would continue with the PZ3 and when you remember the PZ4 prototype initially had Torsion bar suspension and only through matters of cost did it end up with 1/4 elliptic spring suspension.
I shall watch your build with great interest.

[ziddan]

Yeah im aware that there were a number of variants, as with a lot of ww2 german engineering

Got the test bits printed and put together.

Seems that having the 3mm screw for the pivot axis in a brass bushing cut from some 3ishmm inner diameter tube gives good stability, even with just the one contact point, the sleeve is about 6.5mm long and just having to fit one for each swing arm is nice.



When i get around to the road wheel ill be putting similar brass bushings in them, gives a good bearing surface with quite little slop, was initially thinking id do bearings but the ID 3mm ones i have are actually a sloppier fit on the m3 bolts, this wont be a high speed application so i thing the bushing will be fine for a loong time (possibly longer than bearings getting wet and dirty) and if replacement becomes necessary its easy.

This current design allows for an upwards deflection of about 8mm of the wheels, thats about 13cm in scale.

Anyone know if thats reasonable or way small?

[CODY614]

If may ask, What kind of filament are you using?

[ziddan]

Sure, its PLA sold at a chain of hardware/home improvement/mail order stores called Clas Ohlson under their own brand name, they are here in Sweden but also Norway, Finland and there might still be one or two stores in the UK and Germany.

No idea what the PLA they are buying in bulk and rebranding actually is but ive had very good results with it on my several years old Chinese noname DIY kit printer.

I printed these parts quite quickly at .32mm layer height but i will be slowing it down and decreasing layer heights for parts that have visible planes or inclines along the Z axis.

For the actual top of the hull, crew compartment and turret i may even try using my mars 2 mono as it does very good prints, i picked up a bottle of tough resin a a month or two back and ive yet to open it, should come in handy for at least the tracks, the PLA tracks on my 1/10 Opel Maultier were a pain, the even smaller ones to go one this might be an actual nightmare so doing them in resin makes sense, less cleanup and better quality.

[ziddan]

Been working on more bits, just finished up the motor mounts, axles for the drive sprockets, pinion gear for te output axie from the yellow tt gearbox, spur for the drive sprocket axle.

There is some provision for sliding the motors back and forth to adjust gear mesh as well as some possible changes in gearing to adjust the speed and torque, other than two (easily removable) countersunk screw holes on the bottom of the hull there wont be anything that might affect mounting different motors/gearboxes.
These gearboxes were cheap and readily available so im initially going with them but i think those geared N*0 motors might be a better option later on as they have metal gears.
As opposed to the non driven wheels im using bearings, instead of bushings, for the drive axles.



Im going to start printing a side and the bottom of the lower hull today, its probably going to take a while so ill have enough time to work on how the front lifting hooks go as well as the muffler and box on the back attach.

This is what it looks like at the moment:




I figure i should make provisions for adding a smoker in by having a hole through the rear of the hull and into the exhaust pipe.

Is there a standard for the output hose on smokers?

Would a hole of a slightly smaller diameter than the hose, so it press fits, be alright?
Which sizes are common?

[Raminator]

Really neat CAD work ziddan, you're off to a fantastic start! I really like your approach to the suspension units, able to look the part while still being functional and sturdy.

From memory, the stock Heng Long smoke units use 6 mm ID tubing. You'd be able to have it press fit into a hole or over a barb easily enough; it doesn't need to any withstand pressure.

[ziddan]

Thank you, no CAD here unfortunately, have tried to learn it twice but cant get on with the constraints and all the order of operations, im doing this by stupid brute forcing and eyeballing 3d models in Blender

Very useful information thank you, I think ill make a through hole for the exhaust pipe and an internal hose mount that can be changeable without needing to affect the hull at all.

With a bit of luck i might have a smoker to take a look at tomorrow, there are local auctions ending in five hours today, up are a Heng Long gray Tiger, a Taigen yellow/brown camo and zimmerit Tiger and a Torro gray Tiger.

Im given to understand those are all relatively interchangeable and i think these are pretty old, 27mhz all of them so they might not have smokers but im gonna hope for the Taigen or Torro as those have IR, preferably the Torro because its gray.


Currently im printing off the motor mount to see if the motors fit in it.

[ziddan]

No luck with those auctions for me, would have picked a Tiger 1 up if i could get it for cheap but as it was old versions in unknown condition (boxes looked alright tho) i didnt stay with them as the bids started going over 80 bucks for something i was only mildly interested in.

Anyways, modeling goes on and the lower glacis is currently printing. i think ill be able to assemble the lower hull, minus the treads today.

Its starting to look like a model(kit)



I also had a rummage and found the turnigy 9x with djt module and D4R-II rx i havnt been using for years.
Gonna move the module to my flysky th9x as it has been modded with self centering for the throttle stick and had er9x installed, just need to clip the blocking bit so the module will fit.

This in preparation for open panzer later on, not sure which way ill do that yet. protoboard like Serge looks doable, gotta to figure out exactly whats needed.

[ziddan]

Most of the bottom of the hull is together.