Spoke lengths for a 3 cross Blunt 35

Discussion in 'Antique Bicycles Pre-1933' started by Bozman, Jun 12, 2018.

  1. #1 Posted Jun 12, 2018

    Wore out three sets of tires already!

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    Building out some Blunt 35 700c rims to get some wooden rim bikes back on the road. The original metal clad wooden rims have a 3 cross pattern. I've built out Blunt 35s before with cross 4 patterns with 295 mm spokes but I'd like to keep the look as close to the original with a 3 cross. I'll be using either Morrow or New Departure rear hubs and New Departure front hubs.

    My question is how long should the cross 3 spokes should be for Blunt 35 700c rims.

    Thanks in advance

    Boz

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  2. #2 Posted Jun 13, 2018

    Wore out three sets of tires already!

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    Hey Boz, there are those spoke length calculators that scare all but the PhDs in Mathematics. I live in dreaded fear of the hypotenuse. Here's the easy way that I use. Cross 4 is the easiest because the spokes leave the hub at right angles to the hub so the lacing set up is minimal. Each spoke is reaching from the rim to the axle, but with a little angled length as it follows that hypoteneuse. Anyway, lace up 2 spokes that are longer than you need. These are the parallel ones that surround the hole for the valve stem. Screw on the nipples so that you've just hidden the threads. Now install the 2 on the other side of the rim and screw on the nipples the same depth. You can hang the hub on a nail on the wall (for visualization). Gravity will seat the lower spokes while the uppers will protrude through the top. One simply measure the amount of excess spoke and divides by 2. That number is how much to subtract from your overly long set-up spokes.
     
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  3. #3 Posted Jun 13, 2018

    Cruisin' on my Bluebird

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