Road Bike, Cycling Forums banner

1 - 7 of 7 Posts

·
Squirrel Hunter
Joined
·
3,806 Posts
Discussion Starter #1
Weight

Ramjm_2000 said:
I'm fairly certian I've read several folks building v's with alloy nips. Has anyone had any problems with this set-up? seizing, etc...
I am far from being an expert on wheel builds but isn't the reasoning behind using alloy instead of brass the weight savings? Seems kind of pointless to save a little weight on nipples when building up a pair of Deep V's which are on the heavy side to start with. We run a pair of Deep Vs on our tandem and they have been great wheels.
 

·
Defender of Freedom...
Joined
·
611 Posts
I'm fairly certian I've read several folks building v's with alloy nips. Has anyone had any problems with this set-up? seizing, etc...
 

·
Registered
Joined
·
21,504 Posts
Separate choices

As Keeping up with Junior said, shaving a few grams when using a 500+ gram rim seems kind of pointless. That said, I'm not aware that the choice of alloy nipples (or not) is really tied to the choice of rims. The advantage of alloy nipples is to save a bit of weight (ca. 20 gm for a 28 spoke wheel). The disadvantages are having the nipples seize, crack, and corrode over time and round easily when building or truing a high spoke tension (low spoke count) wheel.
 

·
Defender of Freedom...
Joined
·
611 Posts
Thanks all...

while I appreciate your comments on weight, I really just want to know if folks have done this with success. I'm not leaning one way or the other just looking for real world feedback.
 

·
Juanmoretime
Joined
·
2,201 Posts
It's done very regularly.

Ramjm_2000 said:
while I appreciate your comments on weight, I really just want to know if folks have done this with success. I'm not leaning one way or the other just looking for real world feedback.
AC CR420's have them as well as my deep rim carbon wheelset, Rolf uses them on the Vigors and many other factory and custom bulilders.
 

·
Registered
Joined
·
1,859 Posts
Use of aluminum nipples

Ramjm_2000 said:
I'm fairly certian I've read several folks building v's with alloy nips. Has anyone had any problems with this set-up? seizing, etc...
Is this done regulary? Yes.

Do people have more problems? Sometimes.

Aluminum is lighter than brass (the other common nipple material), but it has a few properties that make it less ideal as a nipple material:

1 - Aluminum is weaker than brass. This makes it more likely to round off the nipple or pop the head off.

2 - Aluminum is more prone to corrosion than brass. This makes it more likely to sieze onto the spoke or rim, or simply just corrode and fall apart.

3 - Aluminum has a higher coeff. of friction than brass. This means it can require more torque to turn the nipple - especially after lubrication has washed out in use.

4 - Aluminum is more prone to galling than brass. Galling is a kind of "friction welding" between two parts that are pressed together under high pressure. Aluminum nipples are more likely to gall on non-eyeleted rims, so some type of lubricant or anti-sieze is more important with aluminum nipples.

5 - Aluminum is more notch sensitive than brass. This means that if there is a sharp lip on the edge of the rim's spoke hole, it is more like to score the underside of the nipple head, which can create a stress riser which can eventually result in the head of the nipple popping off.

What this means is that aluminum nipples are not as long lasting, and more care must be taken when building and maintaining the wheels. In particular:

1 - Spokes should be sized to go to the top of the nipple head, so there is full thread contact, and so that the end of the spoke helps to re-inforce the nipple head.

2 - Nipples should be well lubricated, both on the threads, and under head where it rests on the rim hole (brass nipples should be lubricated as well of course, but it is more important for alum. nipples).

3 - a 3-cornered spoke wrench should be used, which grips 3 corners of the nipple flats instead of just two, making it less likely for the nipple flats to be stripped.

4 - Eyeletted rims are preferred for aluminum nipples, to decrease rim/nipple friction, eliminate galling, and because the curved surfaces of the eyelet better support the head and reduce the chances of scoring the head.

If a non-eyeletted rim is used, the spoke nipple seat in the rim should be de-burred, and very well lubricated. Nipple seats can be deburred with a 90 deg. counter sink, or a "cheap and dirty" method is to use a phillips head screwdriver in place of the countersink.

Keep in mind that the weight difference with aluminum nipples is fairly small - any type of nipple doesn't weigh much to begin with. Brass nipples weigh about 1 gram each, and aluminum nipples weigh about 1/3 gram each, so for a 32 spoke wheel, the total weigth savings would only be about 20 grams.

The other advantage (depending on who you ask) of aluminum nipples is that they are available in a wider variety of colors. So if you really want a wheel with alternating red, green and purple nipples, you'll have to go aluminum.
 

·
Registered
Joined
·
3,254 Posts
To answer the specific question about Deep Vs /Alloy

Yes, I have a set 28hole/DA hubs laced using Alloy Nipples. They are training wheels on my TT Bike, which I ride about twice a week. No problems in 3 years of regular use. Hope this helps.
 
1 - 7 of 7 Posts
Top