Jason Cloutier wrote:
>
> Has anyone actually disassembled a Hi-E hub? I have one that
> needs service. I have heard that these hubs need to be
> disassembled to change the bearings. I think the deal is
> that the flanges are press fit onto the center tube and this
> all needs to come apart and the bearings pushed out of the
> flanges from the outside.
Yes I have pulled them apart and the news is not good - it can't be done with normal bikeshop tools as far as I know. [Hang on, I just thought of a way, see last 3 paragraphs*] The force required to pull it apart was not huge, the trouble lies in getting in a position to apply the pulling force.
I used a Bridgeport vertical mill as an arbor press. (An arbor press is a much simpler tool but I didn't have one). I clamped one flange in a vise on the ways, using jaws specially-made with curvature to match the flange. To pull on the other flange, I brazed four spokes to a piece of 5/8" tubing, threaded ends facing down. I put the tube in a collet in the mill's spindle, and put nipples on the spokes after passing them through 4 holes in the flange.
If you have a mill or press that can clamp a 5/8" tube, I still have the 4-spokes tool I made and I could lend it to you. You'd have to come up with a way to clamp the other flange.
*It occurs to me just now that custom jaws could be made for a standard bench vise, so as to pull on the flanges. Then you could just open the vise to disassemble the hub. This is do-able with normal tools (vise, hacksaw, drill, hammer), but probably too much work to save one hub. Read on if interested.
Most bench vise jaws are detachable, held on with two screws. I envision replacement jaws made from bent steel flat stock, with a slot cut into the middle big enough to let the center barrel of the hub in. The flat stock would need to be wide enough to be still strong after having this big slot cut into it - 2-1/2" maybe?
You'd need some blacksmithing skills to put four 90╟ bends in the steel strap, like this: _\u250c\u2510_ (hope my ascii art came through). The two underscore characters are where you would drill the holes for attaching to the vise. The upper cross-bar is where you would slot to let the hub barrel in. You'd need a vise that opens wide enough to fit the length of the axle between the jaws, and then can open still wider, enough to pull the hub parts free. The vise needs to have jaw-attaching holes far enough apart to fit this custom jaw contraption between them - width of the jaw contraption has to clear the hub flange, obviously wider for hi-flange hubs. The bends in the steel strap can be made somewhat more than 90╟ if needed, to get the jaw-attaching screw holes closer together, within limits. Final design of the jaws is left as an exercise for the reader.
Mark Bulgier
Seattle WA USA