Watching TV during the Covid-19 lockdowns I had been seeing the commercial for the DR stump grinder quite frequently. Looking at the product carefully I came to the conclusion, "I can build that." So, when my grandparents had a bunch of trees taken out and needed the stumps removed it was the perfect opportunity to start this project.
While doing further research on the DR website I made a critical error and read bites per second as bites per minute. This lead to a chain of mathematical calculations resulting in this first layout of parts.
During a conversation I went back to the website to check the number and discovered my error regarding the time unit. As it turns out the entire pulley and chain section became unnecessary, greatly reducing weight and length as shown below.
The result is a direct drive from the motor to the cutting head, utilizing a slack-side tension method for clutching. Similar to how riding lawn mower decks are engaged and disengaged. The gray pulley is on an arm actuated by a cable running up to the handlebars.
Cutting head is the Leonardi M1 Blueshark made for the Dosko 200. I purchased mine from CEI Supply, at the time it was on clearance, it does not appear to be available from there anymore.
All of the fabrication work completed and ready for testing.
Testing successful! (Stump was the remains from a white pine.)
Moved into finishing with sandblasting, priming and painting.
Final assembly.
Overall it has performed admirably, removing 40+ stumps at this point, ranging from a few inches to a foot. Total out of pocket was about $650. C-channel for frame came from a scrap truck flatbed, handles and axle portion of frame are from an old 2 wheel tractor, engine came from the shed, and the guard was made from scrap PC service panels. Project consumed the month of June.
Worthy of note: The engine sat in the shed for 25 years, and started on the 3rd pull. Dumb luck I suppose as after that it has been intermittently problematic. During extended use, the engine will periodically lose power and die. Still diagnosing that issue. Head gasket was leaking, replaced that and cleaned the carbon off the head. Rebuilt the carburetor as it was filling with gas and then leaking from around the air cleaner bolt.
