Wheelbuilding - Nipple length

[Joe]

I'm soon to be attempting to build my first set of wheels

I've calculated the spoke length required for the front wheel at 261.8mm or 262mm depending on the calculator. So I've ordered some 262mm DT Comp spokes, however I've just noticed that they come with 14mm nipples. Is this going to be a problem?
Wheelpro's calculator says to subtract 1mm from the calculated sizes for 14mm DT nipples. So I should really be on 261mm, which they don't make anyway...would you round up or down in this case?

Colour me confused

 

[Will1985]

I'm doing this at the moment to build my powertap wheel (except I can't decide between OP, DT RR1.1 or 1.2).

Have you used the DT Swiss calculator? I'm calculating with 12mm nipples and not sure of the difference either when rounding spoke lengths. We'll wait for someone with experience to come and say...!

 

[Joe]

I've had a go but it's giving me totally different numbers to the other calculators! I think it's the "number of intersections" field that's doing it

 

[jimboalee]

I use the formula in Jobst Brandt's book.
Never had a problem.

A word of warning - Although aluminium nipples sound and look attractive, don't use them. The alum fuzzes up and binds to the spoke, Then the spoke key rounds the faces.

Chrome plated brass. Yes.

Oil them well.

There is usually plenty of thread down a std nipple for a spoke to be 2mm shorter than the calculated length. They need to engage at least 5 turns.

A clever tool is an adapted screwdriver where the sides have been ground away to leave a central pip which is lifted by the spoke to disengage the driver blades. The pip should be 1.5mm long. This ensures the spokes are equidistant before the final tensioning - which should be 1/4 turn for every spoke on one side, then every spoke on the other.
The rim is moved sideways, and then moved back.

Bladed spokes - get a small piece of wood with a slot it it to hold the blades while you turn the nipple.


Get Jobst's book And round DOWN.

 

[jimboalee]

There's a link on the CTC website to spocalc.xls, which is on the Harris Cycle Surgery site.

Use this one. It agrees with my calculations from Jobst's book.

Use std brass nipples and you can't go wrong.


BTW, Jobst Brandt is a resident of Stanford, right by the University in California. He shops at Palo Alto Bicycles, as does Steve Jobs, Director of Apple Computers.
Most of the Western Wheelers club shop there as well, inc' me.

 

[e-rider]

most rims are designed to be used with 12mm spoke nipples (brass are best) for some reason CRC ship their spokes with 14mm mipples.

The dt swiss calculator defaults to 12mm nipples - most people tend to use the 'cross 3 times' building pattern.

If you use 14mm nipples you either need more thread cut into them or more commonly slightly shorter spokes, than if you use 12mm nipples.

In my experience, if you have pretty standard rims such as mavic then 12mm nipples are perfect - new fangled rims or DH might require longer nipples

 

[Joe]

Cheers all.
They were indeed from CRC, wish I'd thoroughly read the description first!

With the 14mm nipples I've effectively rounded up the spoke length which I gather is asking for trouble, so I've ordered a load of 12mm nipples instead. Bit annoying, but better safe than sorry for my first build I guess.

I used spocalc.xls, andRoger Musson's calculator which were within 0.2mm of each other. I will also be using his book for the build.

Will let you know how I get on!

 

[02GF74]

A word of warning - Although aluminium nipples sound and look attractive, don't use them. The alum fuzzes up and binds to the spoke, Then the spoke key rounds the faces.

hmmm, dunno about that. I have replaced 2 rims on both my front and rear wheels, mountain bike, due to worn rims using the original alloy nipples and stainless steel spokes. this is not recommended practise - shops would just cut the spokes since it is quicker - but I've not had a problem undoing them. During assembly I do put some grease on the nipples.

There may be one or two that have the flats starting to round off so I doubt I can continue doing this forever.

 

[fossyant]

Hmmm....maybe I should re-build some old wheels....got a set of perfect 7400 DA hubs on Wolber Profil 18 tub rims (don't race anymore), but these would build up into some very nice Open Pro CD's......or ask someone to do it.....properly......hmmmmmm....

OK how easy is it to build a good set of wheels ? I'm fine with trueing wheels, even helping folk out with seriously damaged ones just to keep them going... I think I'm pretty good at it...I keep my wheels within less than 1mm tollerance.....so could I do it from scratch ?

 

[e-rider]

Yes, easily. I've built about 10 wheels now and after the first 2 it's pretty straight forward. I have more confidence in my own wheels, rather than letting a mail order shop build them up. Even the mavic crossride wheelset I bought went straight into the wheel jig before use - and they are not cheapo wheels!

The big problem that everyone has is: what length spokes to use!!!

 

[Joe]

I'm sure you'll find it easier than me Fossyant!
The only time I've ever put a wheel out of true was when I got hit by a car, and I just twisted some nipples (oh er) until it stopped hitting the brakes
Got me a truing stand for xmas, and need some wheels for my tourer, so I'm gonna learn!

 

[Joe]

Ok, well I've laced up my front wheel (36 spokes, 3 cross).



Does it look right?

 

[e-rider]

hard to say without looking closely

 

[NickM]

Crikey, I can't see at that scale (eyesight not what it used to be...).

Did you get the valve hole between two groups of four spokes, so that it's easy to get the pump head in? Failing to do that is a common error...

Assuming that you did... if it's

1) round and
2) laterally true and
3) the rim is central and
4) all the spokes are within a semitone of each other and
5) similar in pitch (when "pinged") to a trusted wheel...

...congratulations! you are a wheelbuilder

PS if you haven't tensioned it yet, make sure that 1, 2 and 4 are the case before applying significant spoke tension.

 

[cchapman]

I agree, getting the right spoke length is the hardest part. The way this is done is
a) go to shop with hub and rim to buy spokes.
shopkeeper uses computer to calculate spokes.
c) take them home and proceed to build wheel
d) find out that spokes are either too long or too short
e) return to shop with evidence to get spokes of correct length.

The next thing to remember is to use 'dri-lube' on the spokes threads.

Then remember to retension after about a week.

An 'American screwdriver' which is a ratchet type that you operate by pushing down like a bike pump would be great!

In spite of what Jobst says I think tying and soldering the spokes gives a better wheel, it certainly gives extra points in the style stakes!