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I designed this model from scratch using Fusion360 the software allowed me to test all the moving parts for correct functionality before printing.
The Digger's arm and bucket can rotate 360 degrees the arm or boom moves up and down with the left lever while the bucket moves in and out with the right lever.
The mechanical movement is achieved through some basic linkages and pivot points.
The entire model is made on a 3D printer and requires no additional hardware to assemble.
To assemble you will require the following:
Some bulldog clips or clothes pegs to use as clamps
Some sand paper
Some needle nose pliers
Step 1: Print All the Components to Make the Toy
Using your chosen 3D printing software open each STL file. The Components are all orientated for best printing. Only the bucket requires supports to print.
I made this toy using a PrintrBot simple metal with a 0.4mm nozzle sliced in Simplify3D using 0.1mm resolution, 50% infill.
Once you have all your parts printed and cleaned up to your liking assembly is fairly straight forward.
Tip: the supportmaterial in the bucket can be removed by snapping it out with some needle nose pliers, and the parts smoothed with some sandpaper.
The parts should just press fit together but a small amount of super glue is recommended to give the model some strength.
Step 2: Assemble the Base
Then take the ring and press it on to the top of the base.
if needed a drop of glue between the parts can be used to ensure they stay together.
Step 3: Arrange the Pegs for Assembly
3x 12mm male and female.
4x 8mm male and female.
1x 8mm male
1x 11mm large male (no hole down the middle)
If using super glue having a number of bulldog clips at the ready will help clamp parts to gather while the glue sets.
Step 4: Assemble the Bucket and Forward Boom
Step 5: Boom Arm
Step 6: Short Linkage
Step 7: Long Linkage
Step 8: Bucket Control
Step 9: Attach Boom and Bucket to Main Pivot
This will be a very tight fit.