WPM


Albert's PistenBully 100 Park (1:12)

Last change: Mar. 7th, 2019

As a little brother for my PB400 ParkPro 4F I'm now building the newly introduced PB100 Park. The challenge is that body, chassis and auxilliaries are practically all completely new designs. And furthermore the smallness of the snow cat brings additional challenges in utilizing the limited space.

The original is also a completely new design and features all the high-tech parts of it's larger brothers, like the 4F exhaust gas aftertreatment and the new operating concept in the cockpit.

The company Kässbohrer kindly gave me access 3D data as an excellent base for creating a true scale model. By the way I have a license agreement with Kässbohrer since 2007.

Brief overview of the planned implementation:
- Chassis + tracks with modified Pistenking parts
- Body as 3D printed parts
- Snow blade: bent metal sheet parts
- Tiller: will be a challenge
- Hydraulics for all functions


PB100 Park (original) at the Kässbohrer location in Grand Junction, Colorado

First drafts of the chassis with the JC model for motivation

The first step is always to design the chassis as a base for the snow cat. Here I'm relying as much as possible on parts by Pistenking. Not only because it makes it easier, but also as they actually correspond to the original. For example the track tensioning mechanism by Pistenking is the same as at the original.

 

 

But I cannot use the flex shaft drive because the bending radiues would be much to tight.

Instead, I'm making a gear set with bevel gears and spur gears, on the left you can see this in the CAD model. The gear box housing will be printed and supported by laser cut metal parts.

 


Here I positioned the hydraulics components (green blocks) in the chassis for checking if they really fit. At the front is the pump, in the middle a 6-valve block (which I have available since the conversion of my PB400 ParkPro), and at the back a single valve.

End of September 2018 I could inspect a PB100 Park at the Kässbohrer office for the Rocky Mountains. I made almost 400 detail photos. A big thank you to the great folks there, who put the PB100 in the center of the lot for me.


PB100 Park (original)


Checking out the PB100 Park :-)

Meanwhile I'm working on the body parts in CAD. I can't show any screenshots though because I have signed a non disclosure agreement with Kässbohrer.

The first parts arrived: printed parts for the sprocket gear box (front black), the sprockets, the master form the wheels, the frame for the backpack, one air intake and small parts. I have the impression that the surface quality of the nylon lasersintered parts by Shapeways is now even better than before.

The first 3D-printed parts have arrived!


Air intakes printed with different materials

For testing purposes I ordered the left air intake out of two different materials to decide which one is better suited for the remaining body parts.
Left in gray is a new methode where the nylon powder is bonded wiht resin. Left in white is the well known laser sinter printing wiht nylon powder.

I cannot determine any real stability differences, but the classic and cheaper methode gives more definition and sharper edges.

 


Next delivery arrived: laser cut parts for the chassis and platform, gears, hydraulic pump

In October and November I was busy on creating the parts for the driver cabin in CAD. Unfortunately I cannot show screenshots due to my rather strict confidentiality agreement with Kaessbohrer. Obviously my CAD models look almost exactly the same as the 3D-data which I got. I don't want to take any legal risks.

I designed the interior of the driver cabin based on my photos and measurements. Below is an impression how detailled these will be. The black parts will be precision printed.


CAD model of the cabin ceiling


Photo of the original cabin ceiling

I could finish the chassis over the Christmas Holidays 2018/19. Wheel arms, suspension and track tensioner are standard parts by Pistenking of which some needed to be modified. The metal sheet parts were glued together in the proven way with UHU plus endfest 300 in the oven. Attention: the generally available version has a new formula and is by far inferior to the old version, which is now only available for commercial purposes. Make sure to use the old version.


The side sheets are exactly like the original.


Side sheets at the original.


Chassis under construction


Secondary gear drive


Suspension and track tensioner

The tracks consist of Pistenking parts which again had to be modified. The cleats were delivered raw. On my Stepcraft CNC mill exact holes could be drilled very efficiently. The wheel guidance parts needed to be cut on a capping saw to fit the narrow wheels. The wheels are casted parts of PU resin which I finished on the lathe.

To assemble the track I made a device out of wood with the exact cleat distances. This allows working very accurately and fast. In addition I treated myself with a Proxxon Micro Screwdriver, a highly recommended tool especially when one has to turn in 368 screws.


CNC drilling of the cleats


Cutting the wheel guidance parts on the capping saw


Ready for assembling the tracks


Track assembling


Finished track


Tracks at the original


Maiden drive on Jan. 9th, 2019 at 4 pm.

I even found a few snow patches in my backyard for the maiden drive to make this event appropriate for a snow cat. Everything worked well right on and the little snow cat moves as planned.

 


Printed parts for the driver cabin

The printed parts for the driver cabin arrived on Mar. 6th, 2019. For higher strength I had the cockpit base and side frames printed in sintered nylon. All other parts are printed in high resolution because the details are much better represented. Also I'll save quite an amount on sanding work. But they're considerable more expensive than the nylon parts. But it is really impressive how even smallest details can be seen.
I had the side air intakes also printed again because I did change the rear side to match the latest version.

   

Back to Overview of Models