Hi Chris/all,
I've hit a weight limit with Axis 3 (it is skipping steps).
I'm looking at ways to reduce the total load by changing out tools but tomorrow I'm going to check if I can swap out the J3 Nema 17 motor with a J2 Nema 23 motor for some extra oompf.
I've done some quick measurements and at first glance it seems like a nema 23 might fit the frame but wanted to run it by you before I dig into too much.
Does this seem like a reasonable idea? And do you know if there is clearance for the Nema 23 motor?
PS: As an update I have finished installing the AR2 upside down (inverted). It has been hanging for a few days now and is doing great. I had to flip some of the motor directions as you mentioned but it went off pretty damn smooth all things considered. Will post some more information later.
P.S.S: I've also run it at a higher amperage which I will experiment with further tomorrow. It gets a bit more power but have you experimented with increasing the amp's over the specified?
I suppose the only concern I would have with using a nema 23 motor for J3 would be having to come up with a new motor mount to fit the nema23 drive to the robot arm. I think it should fit. the other thing is finding a sprocket with the larger 12mm bore. theres room under the cover for a larger sprocket you would just have to recalculate your total steps traveled. You can turn up the amperage to get more power just keep an eye on your motor temp. They shouldn't get hot enough that its too hot to touch.
Awesome, thanks Chris for the feedback.
I've ordered the sprocket & motor and will let you know how it goes. As it is inverted I'm not too concerned about adding the extra weight to axis 2 but will let you know how it all goes regardless.
I've also increased the amps to J3 and it is managing fine. I've got a few meters of cable which, with the help of an online calculator, adds ~5% of power loss.
Hi Paul,
Did you manage to eventually upgrade the motor on J3? If so, what kind of payload can you lift after the upgrade.
Thanks!
A longer nema 17 with a ratio 1:100 would be a easier solution and would not require modifications and add extra weight to the arm. Since the J3 dont need to more fast I think it would be ideal. Nema 23 might be better if have have concern about the speed too.
I need to hang the robot upside down as well and will use replace the j3 motor with the j2 motor. I will make a new mounting bracket similar to this to fit the j2 motor:
Chris has informed me I would need to modify the pulley for the larger motor shaft. How is your robot doing?
