Ultegra hub re-lace / wheel build opinions

[bencemlyn]

Hi All

I have an Ultegra 6700 front hub (with the larger forged flanges, hence is authorised for radial spoking). However this has been 3X laced before (with corresponding notches round spoke holes), and I built this into a radial wheel. The spoke tension was quite low, but it has left small new notches on the spoke holes orientated at 90 degrees to the notches from the original lacing. So... I took the radial wheel apart because I heard that the original lacing notches can act as stress risers to break the hub flange (I rebuilt the radial wheel with a new hub). I want to use the hub again for a 3X front, but am not sure. Opinions (from liberal to conservative):

1) the hub would almost certainly have been fine radially spoked anyway
2) 3X lacing tends to stress the flanges less, so even with the notches from radial spoking, a 3X should be fine
3) however it is laced, the flanges have been compromised, so the safest thing to do is bin it.

Please let me know your opions - its a very nice hub, and personally I think it is probably fine 3X, but I am listening. Thanks!

[Brucey]

I'd suggest that you build it again x3 and not spray it in water that is contaminated with winter road salt.

Apologies if this is obvious, but it is best to do your research about re-using hubs before you build them up a second time.

cheers

[bencemlyn]

Thanks Brucey - seems sensible!

[Samuel D]

I suspect it will be fine as a cross-three build. However, I’ve never been certain how to ensure the spokes sit in the flange indents that the first cross-three build produced. Guesswork has eventually worked for me but there must be a neat counting method to getting this right the first time. Jobst Brandt’s book does not appear to mention a technique.

[Brucey]

if you fit two trailing spokes into the hub, in the indents, you can quickly see if the hub was built previously with a RH or LH staggered rim, if the wheel was built with symmetric or asymmetric spoking etc. Then it is just a question of choosing the right rim and lacing it up in the right order.

If the wheel is to be built asymmetric, always fit all the inside spokes first.

If the wheel is to be built symmetric, there are various other ways the wheel can be laced up, but all take a little longer than an asymmetric build.

If you don't want to re-use the previous spoking pattern in the hub you can give every spoke a 'new seat' for the elbow if you want; spoke washers can both cover up the previous elbow seats as well as improve the loading on the flange so that they are unlikely to cause trouble anyway. Obviously you can't cover up radial spoking marks this way, because they are all on one side of the flange.

An advantage of using spoke washers is that you create a crevice in the hub flange that can be filled with (melted) waxoyl, and the waxoyl will usually persist for several years before it needs to be renewed. Since corrosion around the spoke holes almsot invariably plays a big part in flange failures, this does a very great deal to give the wheel a longer life than it would have otherwise.

cheers

[bencemlyn]

Thanks All

What is will do is align a few of the new spokes with the old 3X notches, and that should hopefully lace to my open pro at the right drillings. If not, I will look at spoke washers.

I tend to avoid taking any of my nice bikes out in the winter salt by the way, but that's interesting advice about the Waxolyl.

Ben