Knee Joint for weight-bearing leg

Help & Support Robot Parts
1

I’m trying to work on a larger project, am on a budget, and as such, I do not have a welder.

I’m looking for a way to make a leg frame with threadall and/or PVC, but am stuck on knee construction.
Every search comes up either for human knee robotics, or weaker leg joints, such as spiders under a food in size.

My issue I’m running into, is while I’m using a linear actuator to contract/expand the leg, I can’t find a way to fabricate a joint that can sustain, for safety’s sake, 200-300 lbs. In reality, it will be up to this weight at most distributed across 4 legs, but I prefer if possible to err on the sake of caution. I’m open to other ways of going this than initially intended, but feel a bit limited due to not having money for a machinist.

Any ideas or suggestions would be appreciated, as I’ve spend a few hours at Home Depot and Lowe’s trying to find a way. Thanks!

2

a leg joint? use a hinge.

3

Could you refer me to a hinge I could connect, that could sustain 200-300lbs, as I was asking? Thanks

4

You can use a mounting bracket as a hinge (choose the appropriate model of course):
robotshop.com/en/firgelli-au … racke.html

5

Thanks, but do you have an idea for how connect it to threadall and keep it stable with 200lbs on it, or can you recommend another cheap but sturdy material to put this on that doesn’t require welding?

6

Go to the hardware store, find a door hinge. You might have to cut it down. You can use brass nuts to attach.