Dude, if these are relatively new cues like you say, you can buy a cue shaft hanger (Straightener) on Amazon that'll keep the shafts straight and straighten mild taper roll that you describe in a short amount of time.I checked mine last night and the shaft is a little off. also checked the girlfriend's cue. I know it was straight when she bought it about 6 months back, but not now, and she's been storing it right.
mine is a little off from about 4" from the tip to about a foot from the tip I'd say about .020, but the tip section is relatively straight to the rest of the cue. Hers wanders off about the same amount but the tip is off the axis of the cue by about .020 or so. I didn't measure it.. I thought hers was worse. How much this affects our game? difficult to tell.
I keep thinking of taking a straight 3" tube and cutting away about an inch along the length so it has an opening , then threading various holes so I can tighten up plastic screws against the shaft in strategic locations and leave them sit with a bit of pressure to help correcting things. I imagine they can be pushed back to closer to straight but if they can stay like that, not sure. I don't know if we both need new shafts or cues, they both have nice precision couplings but they are different from one another.
I'm sure somebody on here knows the actual name of these. It eludes me at present.
I use them to hang several of my cues in the display cabinet, rather than just standing them up put together. I think I paid 15 bucks for 6 of these.
They're 6 - 8 inches long, have a slice running down the length w a loop on top for hanging them from a nail or screw or whatever.
Approx 1/2" thick, Picture a round rubber piece 6" long w a cut down the side that you slip down over your cue tip and hang the rubber deally vertically from the ceiling. No slip rubber holds the cue in place and heavy duty enuf to hand for long periods of time, if necessary.
I've got an old Mali Shaft in one that you could shoot around corners with. It's coming along nicely, but it's been hanging since Xmas!! Lol.
I've heard if the shaft is too old, it'll go back to crooked once this thing is removed. Hope not. Lol.