I adjusted the frame for the front vents and had it all printed, sanded and spray painted. Then I modelled two brackets for connecting it to the body frame. Once I received all the hardware I got it all fixed into place. The blue surrounding panel will be glued to the skins, then I can push the silver vents through from the inside. This way I can still take the skins off the frame if necessary.
After over 40 hours the core part of the center ankle has finished printing. After a bit of sanding with first 60 grit then 120 grit, I test fitted the ankle with the food drive and the foot shell. Only now (after the sanding, of course) I found out that the rounded curvy bit above the pivot point is too close to the foot shell. The pivot point of the ankle and the foot drive didn’t even lign up properly, let alone the ability of the ankle to pivot forward or backward. Also, the center part was too wide and only just wedged into the channel in the foot drive. If I tied the M12 bolt that holds ankle and foot drive together, the ankle didn’t move at all.
So much for tailoring the part to my needs… (see my last post). This morning I changed the 3D model and sent off another print that should be finished in about two days. I don’t think the slight change in design will be noticeable, especially with the center foot under neath the body and hardly on eye-height with anyone.
I continued with the scratch build of the ankle using styrene sheet material. But I had reservation about its rigidity when finished, especially the connection of ankle to body. So I went back to my Rhino 3D model and developed a more strengthened version of the core part of the ankle and started printing it over the weekend. This way I will have less filing and sanding to do and I can tailor the connections to my needs.
For the ankles of the center foot I went back to the styrene scratch build approach that I used on the main ankles and legs. With a few extra 3D printed bits that seemed to work well. As I decided to put the 2-3-2 conversion off for a later date, I will for now fix the center foot to the base plate of the frame. Have to develop a rather sturdy connection as the center foot seems to take most the the bumps in the ground (this according to many discussions in the club’s forum).