[Ventura Roubaix]

Ok , I'm working on building a rear wheel, Its a H Plus Son Archtype, with a Dt Swiss 350 road hub. The erd as I measured it using Roger Musson method in his e-book is 592. I have used 4 different spoke calculator's.
1. Prowheelbuilder.com, nds=288.6, ds=287.2
2. Dt Swiss, nds=288.6, ds=287.2
3. WheelPro(Musson site), nds= 288.4, ds=287
4. Bikeschool.com, nds=288.6, ds=287.2

My main question is about rounding the ds number, according to Musson you round up or down up to 1mm to the nearest number, there seems to be a consensus among the calculators, so the ds number is 287, do I need to round down to 286 or round up to 288?

 

[Ventura Roubaix]

Thanks, dcgriz. I also was wondering if it was unusual for the spoke length for both sides to be the same length considering dish of the wheel. I was going to round down on the nds to 288.

 

[Ventura Roubaix]

After triple checking my rim erd, using Roger Musson and Mike T 1st method on his site, I have change it from 592 to 593. So now my spoke length's are, nds=289.1, ds=287.7. The question now is do I round the nds up to 290 or down to 288?, I will round the ds up to 288

 

[Ventura Roubaix]

Always use the rule-of-thumb for spoke number rounding - "up or down a maximum of +/- 1mm from the calculated length to the available spoke length" (some suppliers only stock odd number lengths and some only stock even number lengths).

The only time I would break this rule is if I was using thin center Laser or Revs - If the calculation was (let's say) 289.1 or 289.2 I'd go down to 288 and not up to 290 if just even lengths were for sale.

But that's me. OOMV.

But if November Dave posts and he contradicts me, go with his opinion as he builds more wheels in a morning than I do in a year.

Thanks Mike T's, I have found a online site(Wheels Manufacturing) that sells in odd and even sizes, So i will go nds=289.1 rounded to 289, ds=287.7 rounded to 288, does this look good to you.