Wheel Building Issue - advice please

Escher303

I'm building a wheel with the following components:

Novatec 771SB front hub 32H
Archetype Rim
DT Swiss Comp Spokes
2 cross

I have checked my measurements several times but each time I come to lace the final set of spokes on the left, disc side they seem to be too short. I have rotated the hub before completing the crossed spokes but with the larger flange on the disc side the final spokes seem to be at too much of an angle and come up short and don't reach the rim. I must have made a mistake in my calculations (but I can't work out what it is) or there's some technique required to be able to hold the hub in it's dished position so the spokes should be long enough. Stumped as to what the problem is.

Can someone check my calculations please and show me where I've gone wrong?

Hub flange sizes:-
L 58
R 45
Flange distance:-
L 20
R 35
ERD = 597

This results in spoke lengths for 2 cross:-
L 278
R 283.7

I've got spoke lengths of 278 and 284 to build with.

On the Novatec website the measurements correlate with mine, however 'offset' is also mentioned = 7,2mm and there is a field to enter this on the wheelpro spoke length calculator but I don't know what that is for. I could just try longer spokes but without learning what I'm doing wrong and understanding how to calculate the appropriate length I will probably make crap wheels.

Thanks for your help

keezx

Offset is for a rim with spokeholes off center.
If your rim is symmetric, fill in 0.

Escher303

Keezx wrote:

Offset is for a rim with spokeholes off center.
If your rim is symmetric, fill in 0.

Thank you. I did work out the spoke lengths without including the offset so they should be the right length. Still baffled then, anyone able to help?

ugo.santalucia

Couple of issues

1) The ERD of Archetype is 592... don't believe the press... it is 592 to 593 end of the story.

2) 32 x 2 cross for a disc build is really NOT a good idea. For disc wheels you want to maximise the entry angle, I tend to build even 28 H at 3 cross where possible and deffo you don't want a 32 built at 2 cross for disc brakes.

Think again...

The size you need for the Novatec and Archetype at 3 cross is 286 FL; 289 or 290 FR and 287 or 288 rear both sides

Escher303

Thanks Paolo

rrsodl

ugo.santalucia wrote:

Couple of issues

1) The ERD of Archetype is 592... don't believe the press... it is 592 to 593 end of the story.

2) 32 x 2 cross for a disc build is really NOT a good idea. For disc wheels you want to maximise the entry angle, I tend to build even 28 H at 3 cross where possible and deffo you don't want a 32 built at 2 cross for disc brakes.

Think again...

The size you need for the Novatec and Archetype at 3 cross is 286 FL; 289 or 290 FR and 287 or 288 rear both sides

I have a set of Archetype rims ready to be built and I have measured them twice and both times I got 1 x 594 and 1 x 595 - Measured twice because my records of others don't match these rims. In the pass I've had 592, 593 and even 591 but that was the first one.

cycleclinic

It's 593mm for the ERD. Been using that since I first started building with these rims and it always works. To get 594 or 595mm you must have measured wrong.