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evilsockmonkeyzed

1:48 Scale Prussian A6-V Build

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Working on the fore and aft sections of the upper section- super structure for lack of a better description.

 

The curve behind he main turrets is compound.  The lower section is essentially vertical, while the upper section is vertical tapering to both sides.  For that reason, I have to clad the sections separately.

 

Below is the lower section clad in 1/32 inch birch plywood.  

 

SSCladding01_zps9a8a6872.jpg

 

 

Before being incorporated into the overall project, all components must pass an exhaustive inspection by the ESMZ quality control inspector...

 

ESMZQualityControl_zps52d8bdeb.jpg

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The lower curve of the barbettes proved difficult to clad with even 1/64 inch ply, so I opted for a two-part epoxy similar to "green stuff".  Apoxie Sculpt is significantly less expensive than green stuff and cures hard enough to sand or tool.  

 

 

 

Cladandfirstsanding_zpsb2205bd6.jpg

 

 

Above has had the material applied and sanded to a smooth finish.

 

I have discovered that these materials can look and even feel smooth, but when paint is applied low spots become immediately apparent.  So, rather than just assuming that it will look good when complete, I test the finish by painting the surface in a contrasting color...

 

Testpaint_zps0d74b625.jpg

 

 

... and then sanding again with fine sand paper....

 

 

Cladandsecondsanding_zpsa3d8b0ff.jpg

 

 

 

The areas that retain the color are low spots and require additional material to be applied and sanded again.

 

By the way, only one of my four barbettes passed the paint test on the first attempt.  

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We also have a dog, three chihuahuas, another tabby cat, a conure and two free-range teen-agers.

Other than Rosie, only one of the chihuahuas take any interest at all in modeling. Lilly can be depended on to destroy any foam pieces that Rosie rejects and relocates to the factory floor.

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Been fiddling with getting 3D printer calibrated.  There is definitely a time price to pay with a low price point unit.  No names until I determine whether the unit is fiddle-ie or the user is incompetent....

 

Have been fine tuning the cladding on the lower section of the barbettes, but really no worthwhile visuals to post.  Plan to finish the bottom cladding this weekend and begin the sections around the barbettes.

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Finally have the 3DP near dialed-in.  Most definitely has significant limitations.  It's definition is not sharp enough for full DW scale prints, but definitely sufficient for structural elements in in DL scale.  Finishing will be needed- i.e. sanding and perhaps acetone washes in some cases, but overall I am pleased.

 

Below is a provisional render of A6-V main turret.  Much tweaking will be required, but this is where I will start.

 

mainturret01_zps7b9274c2.jpg

 

A print of one segment of a main gun next to DW A6-V for scale.

 

MainGunsegmentprelim_zpsc5da3125.jpg

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thats a lot of finishing to be done there , had worried about the cheaper printers not quite living up to their promises ( but was secretely wishing they would ) i wonder how the balance works out between time taken to cad/ 3d print / finish works out against latheing and casting ? having said that the ability to create complex curves / joins would still make the printer a useful tool . just glad i can use your money /time /frustration/mental breakdowns to investigate a new tecnique . keep up the good work emzd

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thats a lot of finishing to be done there , had worried about the cheaper printers not quite living up to their promises ( but was secretely wishing they would ) i wonder how the balance works out between time taken to cad/ 3d print / finish works out against latheing and casting ? having said that the ability to create complex curves / joins would still make the printer a useful tool . just glad i can use your money /time /frustration/mental breakdowns to investigate a new tecnique . keep up the good work emzd

 

More precise stepper motors might improve quality a bit, but the real limiting factor seems to be nozzle size.  This unit comes with a .35 mm nozzle and extrudes a nominal .42 mm bead.  I really don't know enough about the limitations of extrusion systems to be sure, but I doubt that they can be pushed too much more.

 

Looking more closely at the scale pattern on my larger minis, I suspect that the masters are cut with a CNC machine rather than printed.

 

A mini lathe would be the better choice for this specific part, but the printer handles jobs that would require mill instead.  Price-wise, I believe that this unit and a wheel buffer will come in at a lower price point than a decent mill.

 

Just for grins, I plan to at least proto type the stack and turrets with multi-piece prints.  Having already laid them out in TurboCad, it is just a matter of slicing them into manageable units.

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The fascination of watching the print head move back and forth s gradually fading.  Able to spend a little time painting (DW RE towers and bunker complex) and some work on the build.

 

In some ways flat surfaces are harder to model than complex curves.  One of the bottom undercuts was quite a bit out of true, so some adjustments were needed.

 

Below is simple wood filler added to the transition between an under cut and the main bottom of the vehicle.  Wood filler is an excellent material for this application because it cures quite quickly and is designed to sand easily.  I have used a number of varieties, but have settled on Elmer's brand because of its low price and easy availability.  I have yet to detect any serious degradation of the foam in using it.

 

As a bonus, I have included a WIP model of the business end of the main gun barrel.  Yes, Myth much finishing work will be needed, but it's just so damn fun I can't go back!

 

BottomAdjustments_zps3b304ad5.jpg

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Here in the land of the freaks, being "in a gopher" (hovering or otherwise) evokes a very different image than that which I suppose you intended.

 

ah another one of those little cultural differences hey ? a bit like Americans using the term "fanny pack" oh how us Ausrtralians laugh and laugh.

But to qualify i meant no disrespect to any gopher living or deceassead nor those involved in any gopher related idustries nor individuals who may identify with gophers on a spiritual or emotional level .

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Bottom cladding all applied. Minor touch up needed to re-glue a corner that lifted during gluing.

Main turret progress:

My 3D printer has a nominal bed size of six by six inches, but I am finding that 3x3 or 4x4 is the practical limit.

Printing the entire turret as a single unit would have been pushing even the nominal size, so I have been experimenting with breaking larger objects into components.

The first photo is of the front of the turret assembly with the unit pulled apart to show detail. I incorporated holes for alignment pins into each section and then insert .125 inch styrene to line up the sub assemblies. Eventually they will be held in place with permanent glue, but for fitting and testing, I used simpl rubber cement.

FrontPartswithpins_zps21d35f34.jpg

With the assemblies pushed together and viewed from the rear, you can see the recess for a .375 rare earth magnet on the far vertical assembly. This will match-up with a similar recess in the gun pintle keeping the barrel aligned and allowing it to elevate and depress freely. The semi circle at the bottom is the reverse of the same kind of recess in the base of the turret to allow the unit to rotate. Finally, on the back of the two vertical assemblies, you will see the guide holes for pins to align the front with the back assembly.

RearViewFrontAssembly_zps35295d51.jpg

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