[MOC] RC Snow Groomer

[kubic]

 

This project started about one year ago, when I saw this machine in real life. Previously I wasn't impressed at all, but seeing it ignited a spark. I abandoned it because of the lack of snow that particular winter to return to it later. It is inspired by PistenBully groomers, but it is not a scale model. Here is the final outcome :)

 

 

As you can see, it uses Sariel's custom tracks. I'm happy to publish the (probably) first model using them (apart from his models, of course). It was however not the best use for them. They are really bad in snow. While they are OK in fresh snow, they can't propel the model on the ski slope - I was only able to drive downwards. There was also one thing I didn't consider - since the drive wheels are located so low, snow would quickly get there and melt, which caused the loss of traction. Oh well. Ready-made tracks would perform much better, but it was an interesting experiment. It's also unstopable on carpet - the model was succesfully tested by a 7-year-old :) It was designed to be failproof and it does its job very well. Other functions work without any problems. The middle wheels have simple pendular suspension.

 

 

On the rear it features two easily interchangeable tillers. The one above is very detailed and its sides can swivel down. I don't know all the technical terms. It works fine, I like that I can control both sides with a single gear. The moving parts stay in place because of worm gears and friction pins. It doesn't have a razor, but it is also an optional equipment on real machines. The second tiller was designed to be light and simple, just in case the lifting mechanism doesn't function properly. I was actually surprised by how much a single small linear actuator can lift. It required a bit of experimenting with angles, but at the end it would easily lift the heavy attachment or press it down, because the whole thing was suspended on two shock absorbers. Everything can be seen in the video.

 

I'm very happy with the front shovel. It's very sturdy, angled enough to actually flip through the snow, just like in real groomers. It is lifted by an L-Motor with two small actuators. It has the power to lift the entire model. The blade can also be rotated with the use of a worm gear. It's similar to Designer Han's Leitwolf, but functions better. I installed two shocks, which effectively reduce the backlash, but still allow for some movement and act as suspension. At first I wanted to use pneumatics, but they would look messy and not be able to keep the angle. The guide wheels on both sides help a lot when driving through carpet. The sides don't move to be more sturdy, so I added some fake cylinders. They took me well over an hour of experimenting :D

 

 

Cab can be tilted and doors open. The interior is modest, but it doesn't lack anything essential. Under the cab there's a battery box for the lighting - I use LifeLites LEDs. I absolutely love them, because they have 25 pre-programmed sequentions - here we two blinking orange lights on the roof. The building of the cabin was a challenge even of itself, because the width had to be even. In the base two XL-Motors (geared 3:5) need to sit side-by-side , so I had to use bricks and plates to create very strong sides. You can't really do it with a single layer of connectors, and at 13 studs it was way too wide. At the however the use of classic bricks turned out to be a good thing.

It was also my first model to use the 8878 rechargeable BB. One interesting small thing is, the on/off switch is controlled by a hidden lever with a rubber connector, which makes it comfortable to control.

 

Overall I'm happy with the model. Performance on snow could have been better, but it is a beast when on carpet. Functions have more than enough power and the looks are also fine. I managed to hide all the electric components in the base. Some previous Technic groomers had more functions, but usually at the cost of a huge battery box behind cab or some motors inside tracks. I managed to keep my model clean and sturdy.

 

A lot more pictures on my bricksafe: http://bricksafe.com/pages/kubic5/snowgroomer

 

Here is the video:

 

Thanks for reading!

[Leonardo da Bricki]

Looks pretty good. The functions are nice, you implemented them well in this scale.

[jorgeopesi]

I love it and those tracks too, nice use of the springs.

[BusterHaus]

Very well executed! The mixture of RC and manual functions makes it feel like an official set.  By the way, you can avoid snow sticking to your model by cooling it below the freezing point before putting it on snow.  Use your freezer or simply put it outside (not on snow). I suggest removing the battery box during the cooling and attaching it when you are ready to drive the model. 

[kubic]

Thank you for all the replies!

11 hours ago, BusterHaus said:

By the way, you can avoid snow sticking to your model by cooling it below the freezing point before putting it on snow.  Use your freezer or simply put it outside (not on snow). I suggest removing the battery box during the cooling and attaching it when you are ready to drive the model. 

Sounds interesting, I might try that out next time. Thanks!

[Kristof]

Wonderful! PistenBully is this kind of dream model for me, I can't really say why. Perhaps it's a reminiscence from my early childhood when I adored these machines working on steep hils. Anyway, I simply have much more appreciation for a snow groomer than for a car, no matter how cool is it :D

Your model is excellent. Not overly complicated but functional enough. I really like the treads, although I wonder how good grip would they have on a slope. Have you tested some performance? It seems to run wonderfully on flat ground though.

[Oliver 79]

Very nice. I like the shocks on the attachments and the overall look is well thought out and clean. Well done!  

My only criticism is the hubs on the wheels/tracks. It might just be the dark red. I'm not overly keen on the dish usage. Otherwise, a big well done!