Looking at the photos of yours, it looks as though the screw heads holding the sheave together are on the outside face. You had enough clearance on the backside for the nylock nuts? I wonder if a wider sheave could be sourced from somewhere.
I believe I already removed that screw - it was pointed at the end, right between the ropes’ entry/exit point. Spinning the sheave around, I see a small allen head set screw which looks to go to the center/shaft of sheave.
Yes, just barely enough room. Of course, if yours is closer to the housing, you could put the screws in from the back and have the nuts on the outside. You could even use countersunk flathead screws on the backside.
Rats. Not sure what to recommend. It looks like the set screw is all that holds the shiv on the flats of the shaft on the r550. I suppose you could still make it mid-line attachable and just use a smaller climbing line like rock climbers and cavers use. Another possibility would be to maybe cut it in half and then face off a bit more of the cut surfaces, so that you can use a fatter shim, say about 1/4 inch thick, enough to tap a new set screw hole in the shim. An interesting problem!
Sounds doable, although it might be tricky welding down inside the V of the shiv. Probably should get a pro to do the welding.
Hey, you might not have to split the shiv! I have a second unit I never split the shiv on and I just tried it on my regular 13mm line. It worked! The rope sits higher on the outside of the groove but with tension held on the output side on the tail of the rope, it climbed right up. If you had rope slightly smaller than the full 13mm, it would certainly work OK. I may have gone to all that trouble of separating the shiv into halves for nothing! All you may really have to do, if you want it mid-line attachable, is to mill or cut away those parts of the housing I showed in red that hold the rope captive.
I was thinking that might work too. I’ve got the midline attachable worked out but I need to figure out a fairlead to mind the rope. My hopes of using my old Tanaka gas drill for power is a no go - it doesn’t have reverse or a clutch. When I stop throttling, I just start going down. Still a work in progress here. Ideally, I’d like it to run on Vortex and keep my RR above for easy switch out. Your widening of the sheave still seems ideal. When you ascend on 12mm line on your unmodified sheave, are you seeing any rope damage from the increased friction?
No, I don't see any effects at all from quite a bit of use now. It seems a LOT easier on the rope than your average toothed ascender. Nice job on the mid-line attach mod, Fish.
I removed the brake from both my units and have used them that way from the beginning. Doesn't seem to have made any difference. I think the brakes are just dead weight for our use as ascenders. Probably only kick in when descending fast, which we are not likely to ever use them for anymore. I have quite a few trials on these things now and I LOVE them! Just got down from a 60 foot repeated ascent (four times) with one of mine about an hour ago and still had most of the battery juice left.
It should work fine with that rope, without splitting the shiv to widen it. Just keep some tension with your left hand on the tail of the rope coming off the device, once it is mid-line attachable, or else hang a weight on the tail at the ground. That will keep the rope seated in the shiv and not slipping as you ascend. Once it is mid-line attachable, be sure and run a hitch or a multiscender riding above the RollGliss and tethered past it to your bridge.
