Viich

Hi,

I got my hands on an apparently old SA 3 speed hub with drum brake, and a hankerin' for building a wheel from scratch. I've got a cheap aluminum rim, looking at buying some aliexpress spokes.

Now, I've tested and the hub works, so does the brake. There are a few things I'm looking for opinions on:

1. The hub was painted black. I'm considering trying to remove the paint from between the flanges to try to find the model number markings.
2. Is it worth pulling it apart to lube and check before I build the wheel, or would it be just as easy assembled?
3. Lacing pattern - any reason not to do 3 cross
4. Spoke calculator length - where I'm using a single wall rim, I think I want to get as close to the calculated length as I can without going over?
5. The spoke holes on the rim alternate left and right by 3mm (ie. each one is 7mm from edge of rim flat to centre of hole on one side, and 10mm on the other). If assume I use the closer holes to each flange, I reduce the two flange to centre measurements in the UBI spoke calculator, to get 0.1 and 0.2mm shorter spokes, so virtually no difference.
6. Should I get butted spokes or straight?

Any comments on this or anything else are welcome, thanks!

TenGrainBread 

Butted spokes are in 99% of cases better. Lighter and a little more flexible than straight gauge, meaning less prone to breaking due to stress.

dedhed

CAn't help on wheelbuilding but here are some good links for the hub.

https://bikesmithdesign.com/SA/SA-tips.pdf

https://hadland.wordpress.com/2012/0...y-archer-hubs/


Sturmey Archer Service Manuals ? Vancruisers.ca

clubman 

Converting this Raleigh-Sturmey spoke length chart works if your wheel size is listed. I usually go with a mm shorter but if you do go longer, it doesn't take long to dremel or even handfile excesss length. It's recommended to use spoke washers at the flange due to the changes in modern spoke profiles. Rim washers as well with a single wall, no eyelets. I like inexpensive spokes for IGH wheels so straight gauge?.
Sure, clean the paint off while you can.

noglider 

Don't pull apart the hub unless you know it needs it.

bulgie 

The drum brake side has a very large flange, right? So you probably want 2-cross there. More than that and the nipples will be entering the rim at an extreme angle that stresses the threads with a bending load. Same thing with Dynohubs, which used the same shell.

The steel flanges are very thin and most spokes will benefit from tiny washers placed under the spoke heads, effectively making the flange thicker, so the bend isn't hanging out in space. You want the spoke bend to hug the flange. Mark Stonich's advice: "For DT spokes I use 2 washers under the heads of inside spokes (head on the outside) and one for outside spokes. For Wheelsmith I use 3 and 2." I have only used one washer, but I'll try his advice next time, he's The Man. I bought my bag of tiny brass washers so long ago I don't remember where, but someone here will be able to tell you a source for them.

I recommend tightening the cones temporarily to eliminate all play at the rim while truing. Then after truing you can loosen the cones a tad.

Normal cone adjustment on old SA hubs is to adjust the right side first, with the left side loose. Tighten it all the way until it starts to bind, then loosen a 1/4 turn plus any fraction of a turn needed to get the special bent washer over it, that keys the cone to the flats on the axle. This leaves the driver (the thing with the sprocket on it) noticeably loose. Then go to the left side and adjust the bearing play to just a tiny amount, ensuring no pre-load on the bearings or internals.

-Mark Bulgier, Seattle

clubman 

Good to see you on the forum. I've always appreciated the work you put into your catalogue archives and I've spent many happy hours there.

bulgie 

Nice of you to say, thanks, but I don't really do any work on it to speak of. I've got to be one of the laziest "webmasters" ever. Almost all the scanning was done by others – I just throw the files up on the web where you can grab them.

Since others did the hard work, I do feel some obligation to try to keep the site available. I take backups every now and then, and the box it is hosted on has redundant server-grade hard drives. It's all pretty old, and ignored for months at a time though, and I won't live forever, so grab any stuff you'd be sad to see go away.

I promise not to shut the site down on a whim though -- I do consider it a duty of sorts, giving back a little to the community that's done so much for me.

-Mark Bulgier, Seattle

Viich

Actually, the magnet test is showing not-ferrous, and the two flanges are the same size - I think this is 70mm drum, not 90mm. I haven't stripped the paint off the housing yet, but I think I should just to confirm which hub I have so I don't get the wrong shifter.

ThermionicScott 

#2 brass washers are what you want. https://www.amazon.com/Washer-0-0890.../dp/B000FMWWLS

repechage

Yes, thanks for the effort.
Thinking of the late wooljersey image site...

Viich

I think I've just realized that no matter that it was labeled vintage on ebay, I think I may have an XRD3, not a british build. I've posted in the wrong forum!

The profile matches, and I couldn't find another 3 speed 70mm drum brake hub with aluminum shell and equal flanges. Just somebody did a bad black paint job on the whole hub, and someone sold it as vintage......

Dan Burkhart 

Yeah, if the flanges are equal size on a drum brake hub, I'm pretty sure you have a current production unit.If so, any markings on the hub will be printed on, not etched, so removing the paint may also remove the markings.