Question pgsaw lever mounting

I know there has been discussion on this topic before, but I am still confused on what the right way is to mount the lever on the through shaft pgsaw motors.

Currently I am using a M12 bolt through the shaft of the pgsaw motor. I put a nut and washer on each end of the shaft and got it as tight as I could. It worked for a good 10 minutes then came loose and the lever slipped.

In this post from the FAQ @Nick Moxley explains how he agreed the nut pinch isn't enough to keep it from slipping. Instead he used grub screws and a cotter pin on the tightening nut.

I found the picture from his sim in which he is talking about:

And another this one with the cotter pin in the nut he is talking about:



I see the grub screw going through the shaft and the cotter pin going through the nut but I have a couple questions.

1. How do you drill the hole in the bolt for the grub screw to go into? Pretty sure a drill press will just slip right off the side of the bolt, or jump into the threads. And if there is any play in the grub screw or pin the lever will see this play as well.

2. What in the world is going on with that cotter pin in the nut?

Thanks!

Hello !
I use the same engines.
Had the same problems.
This only holds true if you drill a hole through the threaded rod. And an M4 screw through.
Through the levers I've cut a thread and welded the nuts.
Now it's great!

Threaded rod with hole

So I went ahead and drilled a hole as you all recommended. I was originally using a M4 bolt but it actually sheared off. So I went ahead and purchased 1/8 in pins and so far these are working great.

@bixler13 How tight are your pins in the existing holes of the motor gearbox? I have a very similar setup and there's currently a lot of backlash when changing directions because the 1/8 pin is not completely snug in the holes in the motor mount.

I got them as tight as I could , just as i was when i wasn't running the pins yet. That and I am keeping negative pressure on the levers by using bungee cords which has nearly eliminated all of the backlash at the cost of slightly higher running temps on the motors and sabertooth. Still under 50C which is good by me.

Ok, I fixed my backlash completely tonight. After taking it all apart and testing with the M4 bolt, the hole in the sleeve coming off the motor's gearbox was too large (from the factory). The M4 bolt had quite a bit of wiggle room. I drilled the shaft to have an identical sized hole so it also had the same wiggle room. It's slight but its definitely causing my issues.

I finally fixed it by picking up some 10-32 bolts and enlarging the hole in the gear box sleeve and shaft to 3/16 which is ever so slightly smaller than the through hole required for a 10-32 bolt. You can't push it through by hand but it will thread through easily if put in with a drill. There's almost zero backlash now. Only what's in the gearbox itself.

Note: It's important to run the bit through the whole assembly (sleeve and shaft) again when the shaft is inserted to make sure you have a good 3/16 clearance all the way through, accounting for any slight misalignment between the sleeve and shaft holes. I didn't do this on the first one and sheared the head off one of the bolts before it reached full depth. It's completely through the whole assembly so it will be fine the way it was but it's going to be a nightmare if I ever need to get it out. I ran the drill through the second assembly once in place to clean up the hole and didn't have that issue. Went in nice and smooth.

wouldn't a better option be to drill the hole 0.5mm smaller than the screw to go in it then tap a thread in it the same size and thread pitch of the bolt then assembly should be much easier and avoid sheering the bolt as it goes in. just a thought guys