Spoke and nipple length advice please

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niggle
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Joined: 11 Mar 2009, 10:29pm
Location: Cornwall, near England

Spoke and nipple length advice please

Postby niggle » 25 Jan 2015, 11:59am

Hi there experienced wheel building types, I am about to embark on my first attempt. It will be a 26" disc rim being reused on a Shimano DH-3D32 6 bolt disc compatible dynamo hub. 36 spoke, 3 cross.

I have all the necessary information having measured the ERD two different ways at several points on the rim, which all measured exactly the same, and the hub specs from the Shimano Techdoc website:

Rim ERD:

Rim OD & nipple depth method:

rim od 571mm
depth to nipple head 13mm
ERD = 571-2(13) = 545mm

spoke method:

distance between nipples 517mm
nipple length 14mm
ERD= 517+2(14) = 545mm

Hub:

Flange distance = 51.1mm
Offset = 4mm
PCD = 74mm

Flange distance L = 25.55-4 = 21.55mm

Flange distance R = 25.55+4 = 29.55mm

DT SWISS SPOKE CALC:

Left 255.70
Right 256.50

14mm nipples: L = 254mm, R = 255mm
12mm nipples: L= 256mm, R = 257mm

SPOCALC:

L = 255.7MM, R = 256.5

As you can see the DT calculator gives option of specifying different nipple lengths then gives different recommendations based on them.

The original wheel was built with 14mm nipples. I am ignorant as to why one should pick 14,12 or even 16mm. If I went with 14mm the DT suggested lengths are not available from Rose Bikes, only 253mm, 255mm, 256, 258mm.

In my ignorance I feel I should go with 14mm nipples, 255mm left and 256mm right spokes, but I have no experience so advice from those who do would be appreciated to minimise the risk of buying a bunch of spokes at the wrong length and incurring expense replacing them.

I am intending to use DT Swiss Champion 2.0mm plain gauge spokes, unless there is good reason to splash out on DB spokes on a commuting and utility bike?

Two_Trooper
Posts: 13
Joined: 25 Jan 2015, 12:15pm

Re: Spoke and nipple length advice please

Postby Two_Trooper » 25 Jan 2015, 12:26pm

Hiya

Have you tried this sites spoke calculator http://www.prowheelbuilder.com/spokelengthcalculator/

Two_Trooper

JonMcD
Posts: 151
Joined: 28 Nov 2007, 8:29pm

Re: Spoke and nipple length advice please

Postby JonMcD » 25 Jan 2015, 1:00pm

Longer nipple are used on deep rims where a shorter nipple would not protrude from the rim enough to get a nipple wrench on. Presumably the thread in the nipple is longer as well which would explain why a shorter is spoke recommended. I've only built with 12mm nipples and using a nipple driver. If you build with longer nipples/shorter spokes then it seems you would ideally use a different nipple driver with a longer central "spike" so that the blade still releases at the optimum point.

fastpedaller
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Joined: 10 Jul 2014, 1:12pm
Location: Norfolk

Re: Spoke and nipple length advice please

Postby fastpedaller » 25 Jan 2015, 1:18pm

I would go with a box of 100 all the same 256mm and they will come out a better price. the 1mm is really not an issue. I prefer double butted, and use Sapim or DT - other builders will undoubtedly have their own preference, and IME there's not much to choose between them. The most important thing is how you build it/stress relieve it. Quite often my choice of spoke brand comes down to availability at that time.

andrewjoseph
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Joined: 17 Nov 2009, 10:48am
Location: near Afan

Re: Spoke and nipple length advice please

Postby andrewjoseph » 25 Jan 2015, 1:39pm

The guides for my disk wheels suggested 4 different spoke lengths for l&r, f&r, some of which are not made by anybody. All were within 2 mm so I used long nipples and all same length spokes from the middle of the range given, and that were easily available.

Not had a problem in 5 years and several fully loaded tours.
--
Burls Ti Tourer for tarmac
Saracen aluminium full suss for trails.

niggle
Posts: 3237
Joined: 11 Mar 2009, 10:29pm
Location: Cornwall, near England

Re: Spoke and nipple length advice please

Postby niggle » 25 Jan 2015, 3:13pm

Two_Trooper wrote:Hiya

Have you tried this sites spoke calculator http://www.prowheelbuilder.com/spokelengthcalculator/

Two_Trooper

Nearly threw me as it uses 'nipple seat diameter'. If I subtract 2x nipple head depth of 2mm from the ERD used by the other calculators of 545mm, I get 541mm for that figure, then it gives me spoke lengths L = 254.9, R = 255.7 That is pretty close to the others but not quite the same :?

niggle
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Joined: 11 Mar 2009, 10:29pm
Location: Cornwall, near England

Re: Spoke and nipple length advice please

Postby niggle » 25 Jan 2015, 3:44pm

fastpedaller wrote:I would go with a box of 100 all the same 256mm and they will come out a better price. the 1mm is really not an issue. I prefer double butted, and use Sapim or DT - other builders will undoubtedly have their own preference, and IME there's not much to choose between them. The most important thing is how you build it/stress relieve it. Quite often my choice of spoke brand comes down to availability at that time.

Rose Bike's prices are each 20p (=£7.20 for 36) for DT Swiss Champion PG or 31p each 20p (=£11.16 for 36) for Competition DB. Nipples are extra: 40 for £1.61. I cannot find boxes of 100 spokes for less than £14 for 255mm, no nipples (also DT Champion). I am ordering the hub and other bits from Rose Bikes at the same time so no extra postage charges.

fastpedaller
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Joined: 10 Jul 2014, 1:12pm
Location: Norfolk

Re: Spoke and nipple length advice please

Postby fastpedaller » 25 Jan 2015, 4:59pm

niggle wrote:
fastpedaller wrote:I would go with a box of 100 all the same 256mm and they will come out a better price. the 1mm is really not an issue. I prefer double butted, and use Sapim or DT - other builders will undoubtedly have their own preference, and IME there's not much to choose between them. The most important thing is how you build it/stress relieve it. Quite often my choice of spoke brand comes down to availability at that time.

Rose Bike's prices are each 20p (=£7.20 for 36) for DT Swiss Champion PG or 31p each 20p (=£11.16 for 36) for Competition DB. Nipples are extra: 40 for £1.61. I cannot find boxes of 100 spokes for less than £14 for 255mm, no nipples (also DT Champion). I am ordering the hub and other bits from Rose Bikes at the same time so no extra postage charges.

Last time I bought mine from Singletrack bikes - by far the cheapest a few months ago.

niggle
Posts: 3237
Joined: 11 Mar 2009, 10:29pm
Location: Cornwall, near England

Re: Spoke and nipple length advice please

Postby niggle » 25 Jan 2015, 5:59pm

fastpedaller wrote:
niggle wrote:
fastpedaller wrote:I would go with a box of 100 all the same 256mm and they will come out a better price. the 1mm is really not an issue. I prefer double butted, and use Sapim or DT - other builders will undoubtedly have their own preference, and IME there's not much to choose between them. The most important thing is how you build it/stress relieve it. Quite often my choice of spoke brand comes down to availability at that time.

Rose Bike's prices are each 20p (=£7.20 for 36) for DT Swiss Champion PG or 31p each 20p (=£11.16 for 36) for Competition DB. Nipples are extra: 40 for £1.61. I cannot find boxes of 100 spokes for less than £14 for 255mm, no nipples (also DT Champion). I am ordering the hub and other bits from Rose Bikes at the same time so no extra postage charges.

Last time I bought mine from Singletrack bikes - by far the cheapest a few months ago.

Well currently I can buy Sapim Leader spokes x 100 for £26.99 from Singletrack bikes, which is 27p per spoke and leaves me with 64 redundant spokes, having spent ~£20 more than just buying the correct number from Rose Bikes at 20p per spoke...

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Spoke and nipple length advice please

Postby Brucey » 25 Jan 2015, 7:26pm

I'd use 14mm nipples and full-length DB spokes if it were me. Longer nipples are sometimes easier to build with (they don't disappear inside single eyelet rims so easily) and often appear to give more freedom w.r.t. exact spoke length. Sometimes long nipples are easier to work with on the outside too; not every spoke key will drive nipples that don't poke through the rim far.

Given this is a utility wheel I'd use full length spokes because this lessens the chances of nipple failure. Nipples that bear the tension load alone can fail when they are sprayed with salty water; full length spokes don't leave the nipples to do all the work.

The rim you have may crack or get stuffed into a pothole at some point in the future. If you can replace with a similar ERD then fine, but if not then it may be worth bearing in mind alternate rims and what spoke length they need. This could push you +/- 1mm perhaps.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

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hondated
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Location: Eastbourne

Re: Spoke and nipple length advice please

Postby hondated » 25 Jan 2015, 7:38pm

I have just replaced a spoke in my touring wheel with one I had in my garage which is of a lighter gauge can you tell me whether this will do the job at least for a while or should I replace it with a thicker one. Thanks.

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531colin
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Location: North Yorkshire

Re: Spoke and nipple length advice please

Postby 531colin » 25 Jan 2015, 9:32pm

hondated wrote:I have just replaced a spoke in my touring wheel with one I had in my garage which is of a lighter gauge can you tell me whether this will do the job at least for a while or should I replace it with a thicker one. Thanks.


It'll be fine. It'll be even better if you stress-relieve the wheel, that's much more important than spoke thickness, brand, and a host of other stuff folk worry about.
(but its something you can't see, you see.... :wink: )

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531colin
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Re: Spoke and nipple length advice please

Postby 531colin » 25 Jan 2015, 9:35pm

Didn't we have a thread recently about DT nipples and whether the thread was longer in the longer nipples?

fastpedaller
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Joined: 10 Jul 2014, 1:12pm
Location: Norfolk

Re: Spoke and nipple length advice please

Postby fastpedaller » 25 Jan 2015, 9:38pm

niggle wrote:Well currently I can buy Sapim Leader spokes x 100 for £26.99 from Singletrack bikes, which is 27p per spoke and leaves me with 64 redundant spokes, having spent ~£20 more than just buying the correct number from Rose Bikes at 20p per spoke...


Ah yes.... For some weird and inexplicable reason I thought you were building 2 wheels. It must be my brain out of action due to it being Sunday. Ignore my advice :oops:

niggle
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Joined: 11 Mar 2009, 10:29pm
Location: Cornwall, near England

Re: Spoke and nipple length advice please

Postby niggle » 25 Jan 2015, 10:44pm

Brucey wrote:I'd use 14mm nipples and full-length DB spokes if it were me. Longer nipples are sometimes easier to build with (they don't disappear inside single eyelet rims so easily) and often appear to give more freedom w.r.t. exact spoke length. Sometimes long nipples are easier to work with on the outside too; not every spoke key will drive nipples that don't poke through the rim far.

Given this is a utility wheel I'd use full length spokes because this lessens the chances of nipple failure. Nipples that bear the tension load alone can fail when they are sprayed with salty water; full length spokes don't leave the nipples to do all the work.

The rim you have may crack or get stuffed into a pothole at some point in the future. If you can replace with a similar ERD then fine, but if not then it may be worth bearing in mind alternate rims and what spoke length they need. This could push you +/- 1mm perhaps.

cheers

I have three of these rims in all (or Rigida Taurus is 543 ERD, i.e. about -1mm on spoke length I suppose).