Wheel building

[grayvw]

Does anyone have any guidelines on building a budget 20" alloy wheels? In particular, I'm wondering about:
1. where to buy alloy rims (presumably 36 hole), what brand, at reasonable cost?
2. my old Royce Union folder has a 90mm fork dropout spacing and a narrow opening for a 9mm axle. I've figured out that a BMX wheel with a SLOTTED 3/8" axle will fit here while prying the forks open slightly. Anyone know where I can buy one of these?
3. is it possible to buy these narrow front hubs (91mm) anywhere? Old English 3-speeds had this spacing as well, I believe.
3. I'm thinking of an internal gear hub, so does anyone have spoke length data for particular hubs, e.g. Sturmey-Archer AWC or Shimano Inter-3? I'd probably go with 36 hole, cross 3 lacing. I've been told 7.25" works well but haven't actually tried it.

Thanks for any information you can provide.

[Kenal0]

Check with Bike Friday as far as finding rims. I just got a set of built wheels from them for my Pocket Pilot.
Also here
http://gaerlan.com/bikeparts/parts/406wheel/wheelbmx.html

Kenal0

[Speedo]

Harris Cyclery http://sheldonbrown.com/harris/hub.html is a good source for information on rims, hubs, and wheelbuilding. They can provide you with the information you need to select spoke length given the particular hub and rim.

Speedo

[geo8rge]

Spoke length caluclators. They have no secret formula, it is 100% trig.
http://www.google.com/search?hl=en&q=spoke+calc&btnG=Google+Search

I (and others) found that the results were about 2mm more than necessary. You may have to grind off the excess depending on the rim you buy (some have recessed spoke holes).

I got all my stuff from lickbike.com, if you buy every thing from them they will set you up with the right spokes.

Harris Cyclery will build the wheel for you for an extra $40.

I trued it on the bike (no truing stand), but did buy a park tensionometer.

I mostly used sheldon brown instructions. read carefully and compare your wheel to others you have just to make sure.

[Sheldon Brown]

Spoke length caluclators. They have no secret formula, it is 100% trig.
http://www.google.com/search?hl=en&q=spoke+calc&btnG=Google+Search

I (and others) found that the results were about 2mm more than necessary.
That's because the trig doesn't calculate the stretching when tension is applied to the spoke.

Sheldon "http://sheldonbrown.com/spocalc" Brown
+--------------------------------------------------------+
| As far as the laws of mathematics refer to reality, |
| they are not certain; and as far as they are certain, |
| they do not refer to reality. --Albert Einstein |
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