Wheelbuilding - spo...
 

Wheelbuilding - spoke calcs and measuring tricks?

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I have a few hubs and rims to get built up, main thing causing delay is getting the spoke lengths. There's a few online calculators, no problem, juts need the dims of the hubs and rims.

  • Any tricks for measuring hub flange spacing? I have a vernier caliper and a pillar drill flat table (or simply the faces of a good vice) so I could get within a mm from that. Maybe worth drilling a 10mm+ hole in an alu block to get a good square face to measure to.
  • Rim measurements - flat area, tape measure and blocks, measured 3 or 4x across the ID then averaged - likely to be accurate enough?
  • Spoke calculators - any recommendations for one over another and why?

Thanks

 
Posted : 26/05/2024 11:52 am
 deft
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Spoke calculators – any recommendations for one over another and why?

The new version of the Roger Musson book gives you access to his spoke calculator. I haven't built a wheel for a while but I used to use the 'old' version and will probably upgrade when I next need it:

https://www.wheelpro.co.uk/support/spoke-length-calculators/

Rim measurements – flat area, tape measure and blocks, measured 3 or 4x across the ID then averaged – likely to be accurate enough?

I think making some ERD sticks is the way to go here, using the nipple/washer combo you'll build with:

 
Posted : 26/05/2024 1:16 pm
bax_burner, jameso, jameso and 1 people reacted
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Yes, Ryan's videos are very helpful and his explanation of erd very good. I've always made and used erd sticks from old spokes. Don't sweat it on the flange spacing as +/- 1mm here will make bugger all difference to your spoke length.

 
Posted : 26/05/2024 1:21 pm
binman, jameso, binman and 1 people reacted
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I've just used the calculators with all the hubs and rims listed. SJS we're useful as in the rim description they advised to use a slightly different ERD for the rim than manufacturer blurb said.

 
Posted : 26/05/2024 1:26 pm
jameso and jameso reacted
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ERD sticks.. that's helpful, cheers. I didn't see the flange spacing accuracy meaning a lot on the triangulation but wasn't sure if it did once you're into spokes in 2mm increments etc.

Spoke calcs generally have a lot of rims and hubs listed but I'm building with some sample hubs plus a Jones 135m front spaced hub, bit niche.

 
Posted : 26/05/2024 1:30 pm
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Watch out for the Sapim spoke calculator - you would think it would give sane numbers, but it's a few mm adrift.

 
Posted : 26/05/2024 3:11 pm
jameso and jameso reacted
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I've always used the Roger Musson calculator, home made ERD sticks and stood the hub on the kitchen counter and eyeballed against a steel rule.

Of all the hiccups I've ever had, spoke length has never been one of them.

Factory ERD should not be used, always measure your own. They don't know what nipple/washer combo you are using

 
Posted : 27/05/2024 8:05 am
 mert
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I've successfully built many wheels using a tape measure (1980's vintage BnQ), some ERD sticks (home made out of old spokes/nipples) and the DTSwiss calculator.

Never believe Ambrosios quoted ERDs.

To be fair, never trust anyones quoted ERDs... Ambrosio were so far out i was amazed i could even get the tubs on the rims (nearly 10mm out IIRC)

 
Posted : 27/05/2024 8:39 am

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