XE007

HI,
I awaing a Sturmey Archer AW (80's) with a 28h shell and would like to know if it is 2 cross or 3 cross compatible?

Thank you,
Xavier

Kovkov

if it helps, all my 36h aw wheels are 3 cross.

3alarmer 

.
....IIRC, the 28 hole versions of this were originally designed for smaller wheels. I have built at least one 26" rear wheel with a 36 hole version, using cross 3, and it works fine. Cross 2 would also work with that. But as your rim diameter shrinks, when you get down toward the more compact 20" rims, there are some limitations on cross patterns much above 2. The flanges on these steel hub shells are also narrower than a normal old school aluminum alloy hub. So it's (probably) helpful to compensate for that by using small washers on the inboard side of the J bend.

If you skip that, pay attention to your stress relieving . Which you should probably do anyway.

JohnDThompson 

I've always done AW hubs 3-cross, but that's with 36 or 40 hole 590mm rims. The 28 hole hubs were usually found on smaller wheels, like the Raleigh 20 folding bike with 451mm rims. The smaller rim radius might prevent using 3-cross spoking.

Dan Burkhart 

28 hole can usually go either 2 or 3 cross depending on a couple of conditions. If we are talking about a 700c or 27" rim with a box section, ie. not deep profile, 3 cross should be fine with an AW hub. I have actually built an AW into a 30mm profile 28 hole 700c rim with no issues.
For a smaller rim, such as 26 x 1 3/8 or smaller, I would do 2x.

XE007

Thanks. BMX rims are mostly 3 cross compliant and mandatory for the stuff they do and Alienation and other rim makers design them in 28h 3 cross for the front wheel.

Thanks and its good you said that. The wheel I will have built is 24 inches 507. I went with this wheel size when building designing my frame as I wanted something compact yet quick and BMX has a wide array of rims and tires at 406 and 507 so I went that route. My front wheel is 406 but more focused on the rear as it is my deal breaker for having a good build in place.

When I asked the rep about the rim and the hub, he said that as long as it is 14g or less.

Thanks for the help.

Bill Kapaun

Divide the number of spokes by 9.
That's the MAXIMUM number of crosses. INTEGER (N/9)
Larger diameter hubs & smaller rims may force you to use 1 cross less.
IF I were to build it, I'd do 2X and avoid any potential issues.

XE007

Having said that, I am comfortable going this route then as the 24" bmx rim I have is 3 cross mandatory by design.

XE007

So you can 2x a Sturmey Archer AW? Thanks never had one.

3alarmer 

...we're talking about two different things. 14G or less is what will fit into the drilled holes. I'm talking about how the J bend on spokes is a certain width to allow for the wider flanges on aluminum alloy hubs. So with a narrower flange (which is usually the case with a steel hub shell like SA, there's tendency of the spoke to hit the exit hole before the bend is finished. It can lead to more stress at that point, and failure at the heads from flex at an area that already has some built in stresses from the manufacturing process. The extra width provided by spoke washers might help with this, but it's not a huge deal if you do a good job of stress relieving the spokes on the finished wheel.

If you have a regular alloy hub, take a spoke and run it through a hole, then do that with your SA hub, just to see what I'm talking about. It will be obvious once you see it.