just thought I'd show off this bead roller I made in 2022 out of stuff I had in my junk bins. I used it to roll beads on aluminum tubing for an intercooler I was putting in my LJ78 landcruiser.
front view
isometric ish
top view
the body is made of aluminum and the wheels are made of steel. Both wheels have ball bearings - the big wheel has one pressed in, and the small wheel shaft has one on each end of the aluminum block. i dunno if bearings are necessary, I just had a bunch and figured why not.
I think the radii in the wheels were cut using form tools I ground out of HSS. at first I cut the groove in the big wheel to be the same size as the small one but it needs to be wider to accomodate the wall thickness of whatever pipe you're rolling.
the sliding elements are shoulder bolts, and the tensioning element is just a 1/4-20 bolt. I have a few boxes of shoulder bolts so I thought they'd be good as linear elements - in this application my design is not very stiff and you can see the two blocks getting bent out of parallel as you crank down on the 1/4-20 bolt. In practice it's good enough for my use, just a bit cheesy (I would not use this on stainless, but for thin alu it's OK). The crank handle also uses a shoulder bolt and the green bit is a cut down screwdriver handle (which I think is a nice touch).
the biggest flaw with this design is that it has to be held in a vise - but since it's pretty short you end up having to put it in a vise at like 45° to have access to both the crank and rollers. so if I were to do this again maybe I'd add a block sticking out the bottom for the vise to grab onto. and maybe I'd also put the rollers closer to the blocks to give the unit less overhang (for stiffness) - beads are rolled at the very end of the tube anyways so I dunno why I had them stuck out like that.
overall, it's served me and some friends pretty well.
I can't find any pictures of the tool in use but here's a picture of the intercooler for context. the beads don't need to be very big to be effective - maybe 1-2mm or so - and besides if the bead is too big the aluminum tube will start cracking.
cheers, and hope this is useful to someone.
front view
isometric ish
top view
the body is made of aluminum and the wheels are made of steel. Both wheels have ball bearings - the big wheel has one pressed in, and the small wheel shaft has one on each end of the aluminum block. i dunno if bearings are necessary, I just had a bunch and figured why not.
I think the radii in the wheels were cut using form tools I ground out of HSS. at first I cut the groove in the big wheel to be the same size as the small one but it needs to be wider to accomodate the wall thickness of whatever pipe you're rolling.
the sliding elements are shoulder bolts, and the tensioning element is just a 1/4-20 bolt. I have a few boxes of shoulder bolts so I thought they'd be good as linear elements - in this application my design is not very stiff and you can see the two blocks getting bent out of parallel as you crank down on the 1/4-20 bolt. In practice it's good enough for my use, just a bit cheesy (I would not use this on stainless, but for thin alu it's OK). The crank handle also uses a shoulder bolt and the green bit is a cut down screwdriver handle (which I think is a nice touch).
the biggest flaw with this design is that it has to be held in a vise - but since it's pretty short you end up having to put it in a vise at like 45° to have access to both the crank and rollers. so if I were to do this again maybe I'd add a block sticking out the bottom for the vise to grab onto. and maybe I'd also put the rollers closer to the blocks to give the unit less overhang (for stiffness) - beads are rolled at the very end of the tube anyways so I dunno why I had them stuck out like that.
overall, it's served me and some friends pretty well.
I can't find any pictures of the tool in use but here's a picture of the intercooler for context. the beads don't need to be very big to be effective - maybe 1-2mm or so - and besides if the bead is too big the aluminum tube will start cracking.
cheers, and hope this is useful to someone.