My Senior design project - a "Swamp Thing" tracked vehicle clone

[Garauld]

Springtime update! We didn't get much snow here this winter so I only drove Snowzer around a few times when there was sufficient snow on the ground needed to reduce lawn damage. Since I have to keep the wife happy I got to thinking how I could make the tracks less aggressive. The easiest way to do that would be to box out the grouser channels by welding a flat strip over them - all 126 of them. In the attached image, you can see both the original and modified grousers. I hope this works!

 

[ArlyA]

Springtime update! We didn't get much snow here this winter so I only drove Snowzer around a few times when there was sufficient snow on the ground needed to reduce lawn damage. Since I have to keep the wife happy I got to thinking how I could make the tracks less aggressive. The easiest way to do that would be to box out the grouser channels by welding a flat strip over them - all 126 of them. In the attached image, you can see both the original and modified grousers. I hope this works!

Could do them at a 45 for pretty much the same volume of work. Side hill slippage will suffer.

 

[Garauld]

Hi Arly, I'm not sure by what you mean by 45. Yes, I would assume it might slide a bit sideways which should not be an issue in my yard. The next owner can fix that.

 

[ArlyA]

Cut the lugs ends off at a 45%, then cap. (not good pic)

 

[Garauld]

The original grousers were plasma cut from 1" sq. tube x 14" long and 3" from each end were beveled (sloped) down by 1/4". To modify these I first cut the channel ends at 45° and then box the channel by placing a thin strip (1/8 x 7/8" x 14-3/4" long) on the open top and tig welding it down. I then grind a groove in the strip near each end to weaken it and hammer it down to the bottom corner. The remaining joints are then tig welded to seal it. I tried to mig it initially but even using .023 wire put down bigger weld beads than I wanted. I am using 1/16" ER70S-6 tig rod which works nicely and looks good.

 

[airbiscuit]

 

[Garauld]

I may try that!

 

[trackhead]

My grousers are 1.25” square tube and turn easy, side hill ok, but definitely don’t bite as well as a more traditional grouser.

 

[Garauld]

My grousers are 1.25” square tube...

Please post a photo or two of your grousers/tracks. TY.

 

[trackhead]

 

[Garauld]

Interesting design. What's your drive sprocket plan? Engine size?

 

[trackhead]

999cc four stroke Yamaha RX1, 140hp, 85ft/lbs torque. Very light motor.

Sprockets are currently metal but redesign this summer to pour polyurethane like Centerline Designs YouTuber Canadian snowcat builder just did. He’s got a great video on it.

 

[airbiscuit]

Not to hijack this thread, but it would be interesting to see pics of your build, specs, drive/steering mechanism, etc,

 

[Garauld]

Yes, I think Trackhead should open up a new thread with all the gory details of his build. Feedback from the community may save him some grief as like ArlyA did to my project.

 

[trackhead]

I plan to eventually, and I will add the tips here of your bilge pump brake coolers helped me immensely. Thanks

 

[Garauld]

June update - last week, I finished welding strips of steel onto each of the 126 track bars thus closing them off so as not to be so aggressive to my lawn. The ground is still pretty moist from all the spring rain we received so I plan to take it out when it finally firms up a bit to see how bad they terrorize my grass.

In process:

Finished:

 

[Garauld]

I finished relocating and piping up the hydraulic steering pumps from under the driver's seat to the left hand cargo storage box where I should have placed them originally. They will now be much more accessible especially to check the oil level and look for leaks.

Before:


Now:

 

[Garauld]

Happy Holidays everyone! I wanted to post a quick note on my recent tweaks to Snowzer as well as field testing experiences. We got some snow recently so I was able to do some laps around the yard. The welding up of the track grousers worked very well - actually too well and as Arly implied, it made traveling side slopes very dicey. I plan to make and attach some clips to the grousers that should reduce the skating effect. Snowzer does now however, turn on a dime with the new electro-hydraulic steering brake system. I kept getting a lot of clattering that sounded like parts of my tracks were hitting hard plastic. I tracked it down to a slight misalignment of the rear drive sprocket CL to the receiving wooden wheel CL The metal track guides were hitting the plastic thrust faces of the wooden track wheels thus making the racket. With that problem solved, I still seem to get an occasional loud bang which implies that the conveyor belting I used for the tracks is stretching too much under load and is just jumping the sprocket teeth. I am evaluating options to try and fix that too. Got any ideas other than replacing the belting? More to come!

 

[trackhead]

Yes, buy some two part polyurethane, draw up some sprockets on CAD, 3D print some moulds, and pour some nice new durable sprockets using the same polyurethane “real” snowcats use. You can improve/optimize your tooth height/angle of approach/departure.

I did that this summer with my snowcat and have had excellent results. Used the stuff below.

Tough-Cast 65D Casting Resin

Tough-Cast 65D is a two part semi-rigid casting resin that is virtually indestructible. It's designed to make durable prototypes, and reproductions.

specialtyresin.com

 

[ArlyA]

Happy Holidays everyone! I wanted to post a quick note on my recent tweaks to Snowzer as well as field testing experiences. We got some snow recently so I was able to do some laps around the yard. The welding up of the track grousers worked very well - actually too well and as Arly implied, it made traveling side slopes very dicey. I plan to make and attach some clips to the grousers that should reduce the skating effect. Snowzer does now however, turn on a dime with the new electro-hydraulic steering brake system. I kept getting a lot of clattering that sounded like parts of my tracks were hitting hard plastic. I tracked it down to a slight misalignment of the rear drive sprocket CL to the receiving wooden wheel CL The metal track guides were hitting the plastic thrust faces of the wooden track wheels thus making the racket. With that problem solved, I still seem to get an occasional loud bang which implies that the conveyor belting I used for the tracks is stretching too much under load and is just jumping the sprocket teeth. I am evaluating options to try and fix that too. Got any ideas other than replacing the belting? More to come!

If your tracks and jumping on the sprockets, you sure will feel a jolt. This action will tear things apart.