What a humbling experience! I've built 100's of wheels before but I've got to be doing something goofy and I can't figure out what it is.

Chris King Classic front hub, Mavic Open pro rim, 32 holes, cross 3. Depending on which spoke calculator I use I get answers from 295 to 277mm. I'm using 295mm spokes which I realize is on the short end of the range, but they look to be around 3 or 4mm short.

I'm tempted to just buy some 298mm spokes but I'm kind of reluctant to do that until I figure out what I'm doing wrong. Anybody have an idea?

Check the lacing one more time, are the 2nd 8 spokes on the right side of the first. Sometimes if you get it backwards, everything looks right (at least untill you realise that it doesn't really look right.. )and the third set of spokes gets short after 2 or 3 are in place.

Short flanges on the Hub- try crossx2--Start again on the calculations

Just guessing as I put my wheel builds out to someone who knows what they are doing

My wheel builder had a similar problem with my Tandem wheels. First set of Hope Bigun hubs to downhill rims laced by 3 were fine. Second set felt different and were only X2 lacing. The builder had made a mistake but did not spot it till the wheel was half built. It did make a difference on the ride but shortly after I changed the Forks and got a Thudbuster so did not feel the difference.

I recently came up similarly short on a wheel build (old Campagnolo Record high-flange hubs, 27"* 36-hole Nisi rims, 4X)-- most embarrassing for someone who has built dozens of wheels and who used to work at a bike shop.

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* My initial reaction was that I ordered spokes for 622mm / 700C rims instead of 27", but I rechecked my work several times. I'll probably cross-lace to a set of 700Cs, perhaps even the bike's original tubular rims, and move on. ...

Perhaps your wheel is too large and your spokes are just fine?

I actually considered that possibility. I cut two spokes to exactly 250mm, locktighted nipples onto them and inserted them into opposite spoke holes. Then I measured the distance between them to get the effective rim diameter. It turned out to be very close to what I expected it to be.

I checked all of the significant hub dimensions (except for spoke hole diameter) too.

Well, one could argue that the diameter of the rim's spoke hole circle is too large, compared to either a box rim or an old Araya.

Are the spokes too short at one end only or at both ends?

I'm thinking they're short on both ends. When I measure from the middle I get the exact same answer to each end - right down to the 10th or a millimeter.

Does anyone make a "spoke stretcher?" I think there is a market!

I've not seen a spoke stretcher, but if you use an unsanforized rim.........a few washings.........hot water............

Yep, they sell one at the auto parts store, right next to the blinker fluid.

You'd think by now an official spokes person would have chimed in.

You don't suppose that running my spokes through the dishwasher could have anything to do with it?

It just might be too cold. Wait till summer to finish the wheels..............

Woo hoo! I figured it out.

There were actually 2 separate problems. My spokes really were about 2mm short. Normally I would have been able to lace the wheel with spokes that short, but I also had the pattern, relative to the 2 flanges, off by one hole. Each problem kept me from being able to see the other.

The nice thing about a problem that stumps you is how good you feel when you finally figure it out. The more frustrating the problem, the better you feel after solving it. I'm feeling pretty good this afternoon.

I hope it's warm next weekend.

Maybe the spokes weren't too short, but the wheel was too long?