Originally posted by Russ
Hi. I have an observation about what part of the driver is load bearing when putting weight down through the handle and using the lever arm to turn the barrel. The barrel has maybe 0.5mm to 1mm of vertical play, even when putting a lot of weight through the handle, which leads me to think that the grub screw is taking the load against the bottom of the groove in the chuck shaft, rather than the brass bushing taking the load.
Cheers
Russ
Originally posted by Russ
I have just subjected the driver to a heavy load test by cutting a hole into wood with a 25mm flat wood bit. I took the grub screw out to inspect it and found a tiny shiny flat spot where it had contacted the bottom edge of the groove in the chuck shaft, suggesting it is taking the pressure from the handle.
Originally posted by D Evans
Russ,
I like the follow-up details. I’ll probably never have a reason for that sort of test but a video to see what you did would help me. My usage will be for home repairs and opening beer… [My wife is why I live, beer is what it enjoy when she’s had enough of my shit.]
Originally posted by Russ
D, hi, I’m not set up for videos and editing unfortunately, otherwise I’d love to make one.
My Sunday project (which coincidentally annoyed my missus, and I can’t drink beer due to a medical condition), was to use a couple of files and a lot of patience to extend the groove in the chuck shaft (oh how I long for a workshop with a lathe), which seems to have done the trick.
Hey Russ,
I commend your patience! You are correct, the brass bush is designed to engage with the handle and it should not be seating on the dog point grub screw like you mentioned. The Driver will have likely functioned OK, but if you’re putting some serious force through it, you did the right thing by adjusting that groove position!
Cheers,
Peg
Originally posted by Russ
Peg, excellent, thanks for confirming that I did the right thing. Much appreciated. 
Originally posted by Mark Young
Peg, can we get a wee video showing the mod needed? Cheers.
Originally posted by Russ
Hi Peg, last update on this. So with the bent arm clicked in place, there was still a lot of play between the chuck and the barrel, which I wasn’t very happy with. I decided to remove the dog point on the grub screw, and the now wider end of the grub screw took up some slack in the groove. Now there is an acceptable and minimal amount of play between the chuck and the barrel. Boy that grub screw was difficult to get through with my rotary tool and carbide disc…
Russ
Originally posted by Mark Young
Peg, if not a video, perhaps a few photos to show what is required? Cheers. Mark
Originally posted by Russ
For my final test I disengaged the grub screw from the chuck shaft. I repeated the previous test of cutting into wood applying pressure to the handle. This time the handle fully engaged with the brass bushing and was smooth. I maintained the pressure while ratcheting and the barrel caught the chuck as expected. So on subsequent ratchets I released some pressure from the handle, then reapplied pressure as I drove into the wood. This sequence works perfectly.
In conclusion I am thinking the groove in the chuck shaft could do with being cut a tad lower than its current position.