4 reactions
ttI mExcavator with working treads and arm
I was inspired by road work around the corner from my house.
I started with the treads after researching how they worked. I cut grooves on a router table with a planing bit and then cut those strips into individual pieces for the tread plates. I created a simple jig to make the 200+ brackets needed for the pieces’ hinges and attached them to their backs one at a time. Mistake #1 :y first hinge design was slightly diagonal, which didn’t work as efficiently as I hoped, so I redid them in parallel lines which worked much better. I cut gears with grooves to catch each axle, built the undercarriage to support them, and fitted it with the upper and lower rollers for the treads to ride on.
Next I made the rear box (counterweight) and the rotating platform (the “house”). I shaped the cab on a bandsaw and scrollsaw. Mistake #2 carved the cab chair just a bit too large — it fits, but seems cramped. Anyway, I carved the tiny interior controls and outer fixtures from scraps, and attached the assembly to the house platform.
The thicker part of the arm (the “boom”) is two planks glued together after cutting the joint openings and side designs with a router and planer bit. The hydraulics are dowels mounted on hinges. The bucket was part of a log hollowed bandsaw-box style. Mistake #3 :he bucket is twisted a few degrees off-center for reasons I still don’t understand, which I didn’t catch until it was too late to fix but isn’t very noticeable. I built a base for the boom with another hinge and mounted the entire assembly to the house. Then I attached the undercarriage to the house with a 1” thick dowel so it would rotate freely.
I finished the project with a mineral oil bath and fine-sanded to 3000 grit. Mistake #4 :he center axle joint snapped off when it was weakened during the oil saturation. I should have seen it coming; the dowels securing it were too thin and short. I strengthened it with a bigger dowel through the center and it’s much stronger now.
I had planned to add hydraulic lines to the arm by steam-bending thin dowels. But they looked amateurish and drew too much attention, so I gave up on that idea.
The entire project, including mistakes, took about five weeks. The principal woods are maple, walnut, and cherry. About one-third of the finished product is scrap from other projects. It contains absolutely no metal, plastic, or stain. I’m very pleased with the way it turned out overall, although honestly the part I’m most proud of is the treads (also the most time-consuming). Very fun build.
#diy :
source
I was inspired by road work around the corner from my house.
I started with the treads after researching how they worked. I cut grooves on a router table with a planing bit and then cut those strips into individual pieces for the tread plates. I created a simple jig to make the 200+ brackets needed for the pieces’ hinges and attached them to their backs one at a time. Mistake #1 :y first hinge design was slightly diagonal, which didn’t work as efficiently as I hoped, so I redid them in parallel lines which worked much better. I cut gears with grooves to catch each axle, built the undercarriage to support them, and fitted it with the upper and lower rollers for the treads to ride on.
Next I made the rear box (counterweight) and the rotating platform (the “house”). I shaped the cab on a bandsaw and scrollsaw. Mistake #2 carved the cab chair just a bit too large — it fits, but seems cramped. Anyway, I carved the tiny interior controls and outer fixtures from scraps, and attached the assembly to the house platform.
The thicker part of the arm (the “boom”) is two planks glued together after cutting the joint openings and side designs with a router and planer bit. The hydraulics are dowels mounted on hinges. The bucket was part of a log hollowed bandsaw-box style. Mistake #3 :he bucket is twisted a few degrees off-center for reasons I still don’t understand, which I didn’t catch until it was too late to fix but isn’t very noticeable. I built a base for the boom with another hinge and mounted the entire assembly to the house. Then I attached the undercarriage to the house with a 1” thick dowel so it would rotate freely.
I finished the project with a mineral oil bath and fine-sanded to 3000 grit. Mistake #4 :he center axle joint snapped off when it was weakened during the oil saturation. I should have seen it coming; the dowels securing it were too thin and short. I strengthened it with a bigger dowel through the center and it’s much stronger now.
I had planned to add hydraulic lines to the arm by steam-bending thin dowels. But they looked amateurish and drew too much attention, so I gave up on that idea.
The entire project, including mistakes, took about five weeks. The principal woods are maple, walnut, and cherry. About one-third of the finished product is scrap from other projects. It contains absolutely no metal, plastic, or stain. I’m very pleased with the way it turned out overall, although honestly the part I’m most proud of is the treads (also the most time-consuming). Very fun build.
#diy :
source
| 14,000 mlx | |
| 21 | |
| 4 |