I tried a slight ramp, but boy would not walk. If ramp is too steep, boy falls on his face.
Checked magazine article, said to round bottoms of his feet, so I did. This made it worse.
Went back to article, found that head is not centered on the body, like I did it. The 3/8" dowel hole in the head is supposed to be 13/16" back from the front.........or 1-1/8" from the back of the head, so need to fix that.
Pattern does not say where feet go onto the legs. I tried 1/4" from the back, may need to experiment with this.
Magazine also had picture of rounding the bottom of his shoes..........and I rounded in wrong direction !! Need to fix.
I found a video of a similar robot walking down the ramp. You can use this link to watch this video.
Through internet searches, I found this detail on how to make the shoes.
According to the video above of the similar robot walking, he must sway side to side in addition to rocking forwards and backwards.........so this means the shoes should be curved in both directions!!
2.75 by 2.75 inches is bigger than the magazine plan calls for the shoes, but I can try it, I could also narrow the shoes also while keeping the 7 inch radius curvature intact.
The lathe method will give close to perfect results. Trying on 2 directions on the belt sander may not be close enough, I could try scroll sawing in the 2 curves one at a time also, not sure how well this works.
I went ahead and started with a 2.75 by 2.75 inch oak piece, 5/8" thick. I used 2-sided carpet tape to hold on the lathe small faceplate, which worked ok.
I made a paper pattern in sketchup with a 7 inch radius, to judge the curvature.
I used the carbide round edged tool to carefully turn the piece until it fit the pattern.
I then sawed down the shoes to the size called for on the plans, removing equal material from the sides to preserve the curvature. I then band sawed in half and screwed them to the legs, centering the legs on the shoes.
Some success..............he will walk down the ramp without his heavy head. Does not work yet with his head on.
I'm disappointed in the magazine plan, because I expected the trial and error work would already be done, and if one built to the plan, it would work!!
Looks like I am going to have to figure out the key variables myself.