Hey all. Having a issue on the arm with Clawbot build Gen 2. I’ve had two robots do this so far. The first robot I switched out the top two “2x Wode, 2x2” connectors from the teacher kit I have. It fixed it. The second robot doesn’t seem to be fixing with the change in connectors. I also rotated the 4x4 plate 90 degrees to see if it was an issue with the holes. We have examined the build in detail and it all seems right.
The top 2 connectors keep popping off when the arm is fully lifted. You can slowly watch the connector pull loose as it raises up.
Any ideas?
Hey @Barry_Carter_II , an interesting concept is happening here. The weight (or force) of the claw assembly when raised is creating a moment that is too great for the 2x Wide, 2x2 Offset Corner Connector to hold, resulting in the failure you are observing (see first image below).
When redesigning to improve a build, it helps to study the purpose of the previous pieces. For instance, the 2x Wide, 2x2 Offset Corner Connector was used for two purposes;
- to secure the top arm of the 4-bar arm to the claw assembly
- to allow the top arm to rotate freely without interference
We’ve experienced this failure too before, here is just one simple redesign of the top corner connector. We added two 1x Pitch Standoffs as well as two 1x Wide, 1x1 Corner Connectors. I can provide a more exploded view if more assistance is needed in creating this. I’d love to see what you can come up with to prevent this failure! And remember, the Clawbot was not designed to be a perfect robot, it is only a starting point for you to make improvements on 
glad to see you’re finding improvable regions!
Matthew. Thanks. My student side come up with an alternate fix. It had to do with the arms themselves. I’ll post a pic tomorrow.
Another cause of the 2x Wide 2x2 Offset Corner Connector failing involves the 1x Pitch Standoff near the top of the arm; when the arm is extended to maximum height the standoff acts as a hard stop for the arm. This results in a levering action potentially causing the same failure you’re experiencing. Just another thing to keep an eye out for with redesign. I hope to see your fix soon!
