Umbrella ATC - Acorn Compatible

[suntravel]

Aluminium is ok also, only the max. distance to switch the sensor is shorter compared to steel.

Uwe

[RJS100]

Here is what the cam looks like at 160 degrees:

https://www.dropbox.com/scl/fi/z2sms3rm ... ix14b&dl=0

Best... Richard

[cncsnw]

That looks good.

Do you have any idea yet how the controller/driver/pulse generator you will have running the motor is going to perform starts and stops?

I.e. will there be a ramped deceleration when it is time to stop, or will it just cease sending pulses, and let the motor do what it will?

[RJS100]

Thanks Marc. You are one step ahead of me

I am using an SMC01 controller that allows you to set the deceleration from a scale of 1 to 100. I am using this same controller on another project and it was fairly easy to program.

Here is the manual: https://www.dropbox.com/scl/fi/8bqvjnsi ... wi043&dl=0

This guy has a few videos on programming options:

I bought two from Aliexpress for $6.30 each delivered or you can buy the same think from StepperOnline for twenty bucks + freight.

I will post the process as I move ahead.

Richard

[RJS100]

I received the linear rails today. All looks good. There are four plastic brackets of some sort that came with them. Any idea what they are used for? I didn't see anything similar in the Hiwin spec sheet.

https://www.dropbox.com/scl/fi/xwz4shuc ... hareb&dl=0

https://www.dropbox.com/scl/fi/jv6728hx ... n9nvh&dl=0

Richard

[centroid467]

Keeping the balls from coming out if you slide the blocks off the rail?

[RJS100]

Thanks. So as long as I don't take them off the rails, I won't need them. Kind of like ball nuts and ball screws.

Thanks a lot.

Richard

[RJS100]

Below is a link to a video from a guy who built this same tool changer. The video was created to show some tweaks he made to the design after 8 months of use. The Geneva cam is comprised of two components. The cam and the part it mates with, the "gear". At around two minutes into the video, he talks about the need for the cam to mesh tightly with the "gear" in order for the ATC to work consistently.

The original ATC design had gear and cam both machined from aluminum. He modified the design and made the cam out of plastic. He said this worked better since it eliminates aluminum rubbing on aluminum.

Do you think it would be a good idea to make the "gear" out of UHMW (Ultra High Molecular Weight Polyethylene)? UHMW is known to be highly abrasion resistant with a low coefficient of friction and is self-lubricating?

What do you think?

[suntravel]

I would use Black POM

https://www.sspseals.com/materials/blac ... ymethelene

Uwe

[tblough]

POM in the States is known by the trademark name Delrin, if that helps.