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Would you ride a wheel that…(9 posts)

Would you ride a wheel that…TFerguson
Sep 2, 2003 11:58 AM
skips every third spoke hole in the hub? In other words, there are only 2/3 as many holes in the rim as in the hub. The rim holes are evenly spaced so the spokes will be pulling at a somewhat different tangent than normal. It will be used on the front of my track bike.

Thanks,
TF
Sure,TJeanloz
Sep 2, 2003 2:59 PM
Skipping holes at the hub is something I wouldn't be afraid of doing, unless I were really heavy (>220lbs).

Skipping holes at the rim is a different story altogether, though I have seen it done.
re: Would you ride a wheel that…bimini
Sep 3, 2003 6:08 AM
You will find that you will need slightly different spoke lengths depending on how the holes line up and the different tangents. Not sure if you will need 2 or 3 different lengths on the front. The tensions will need to be slightly different on each length.

Should work fine but it will be a tough build to fiqure out.
Sure, if the spokes were a proper gauge.jw25
Sep 5, 2003 9:27 AM
I'm guessing you're doing a 24 hole rim with a 36 hole hub. There shouldn't be any problems, but the spoke size should be something realistic. Considering it's for track use, you could do 14/17's with alloy nips, but for the road, I'd want something a little heavier.
It also depends on the rim. If it's a deeper-section, the rim itself is stiffer and stronger, and can distribute spoke tension more evenly than a skinny box-section rim. For example, I have a set of Cosmic Pros, 16 hole front and rear, that I respoked with 14/15g Sapims. Since they have 38mm deep rims, I feel fine riding them on bad roads, and in point of fact, they've taken a beating without going out of true.
Daimon Rinard did, but only for rearsoff roadie
Sep 5, 2003 2:04 PM
http://www.sheldonbrown.com/rinard/36-24.htm

I gather he's a pretty good wheelbuilder, and I use his spocalc spreadsheet for almost all my wheel build calculations.

In your case, I see a potential problem I. I'm pretty sure it is impossible to lace both sides of the wheel ideintically. That means diffrent spoke lenghts and lacing patterns on the two sides- which could look goofy for a front wheel, and may cause uneven spoke tensions and affect wheel durability.

What happens is that that one side MUST have 4 radial spokes (obviously all the same lenght) and 8 non-radial (also all the same lenght, 4 leading, 4 trailing) spokes. The other side can have NO true radial spokes, but all the spokes can be the same length (6 leading, 6 trailing).

For apearances sake on a front wheel, probably the best you could do is lace them all as direct as possible which would LOOK radial, and ACT radial, but wouldn't quite be true radial lacing- most of the spokes (8 on one side, all 12 on the other) would "lead" or "trail" very slightly, say by 2 or 3 degrees. You could probably get away with all 24 being CUT to the same lenght, but the threadied portions would vary a little bit, as might the final tensions.

If you want 1x or more interlacing, its gonna look really funky- one side will be crowfoot, the other will be conventional cross lacing. You would also hve 3 diffrent spoke lenghts on one wheel, which could be a headache when building.

Please don't ask me to prove this is fact, its just what I've deduced laying out various odd lacing combos using a CAD program...

I think this is why Rinard uses the method to build REAR wheels. He puts the side that MYUST have radil spokes on the left. His design ends up looking like they a normal "half radial" wheel, as shown in the link above.
It’s a 16h rim and 24h hub…TFerguson
Sep 5, 2003 7:06 PM
and my current plan is to do the pseudo-radial lacing. The way I'm visualizing it, doing a use 2/skip 1 on both sides, I would have 8 spokes one length (4 per side) and 8 spokes another. I would definitely have more trailing force on one side and leading force on the other, which I think is what Rinard refers to as hub torque. Since I have no breaking or accelerating forces on a front track wheel, I do not see this as a problem (agree?). FYI – the rim is a 40mm aero 3x wall aluminum with about 1 cm by 1cm rectangular nipple washers that go against the middle wall. The hub is a NOS American Classic track hub with very thick flanges.

off roadie - I have to admit that, without visualization, I cannot follow your "requires two lacing patterns" argument above. I wish I had taken a copy of a drawing program with me when I was laid off. The engineers used Autosketch (AutoCADs little brother) and I really miss it.

Thanks for all your inputs,
TF
It’s a 16h rim and 24h hub…off roadie
Sep 5, 2003 8:35 PM
With the 36 hole hub and 24 hole rim, it boils down to the fact that you can only line up the hub and rim in such a way that one set of holes (rim and spoke both, taken as a collection) has 4 fold symetry, while the set for the other side has 6 fold symetry. Rinards pictures fail to convey this because they don't show the whole lacing, but its pretty clear when you go to do a lacing diagram of such a machup.

The setup you propose has a similar issue, but there is still no need for any net hub torque. I've attached a drawing showing how- blue represents one side of the wheel (hub holes, spokes, rim holes drilled towards that side) and violet represents the other side.

There would be 4 radial spokes, 2 leading spokes, and 2 trailing spokes on one side. As they are all "near radial", lengths would be very close. This side would be somewhat odd in that it only has ONE line of sysmetry- in my drawing, its the vertical line. Still, the torque balances out, just as it does on the left or right side of any normal wheel. It shouldn't cause any trouble, its just somewhat unusual looking, because it does NOT use a basic "fill 2, skip one" hub pattern.
The other side would have 4 leeading and 4 trailing spokes, and has 2 lines of symetry. It DOES use a "fill two, skip one" pattern.

BTW, the program I use is "Rhinocerous 3d." I've never used it for what I bought it for, but its still a lot of fun. Kind of pricey for a mathmatical doodling pad, though...
why not use a 32 hole hub?off roadie
Sep 5, 2003 8:51 PM
BTW, you can get a somewhat more regualr lacing from a 32 hole hub. One side would be laced with 8 radial spokes in a "fill one, skip one" pattern, and the other would be laced with alternating leading and trailing spokes in a "fill two, skip two" pattern. I think the appearance of the first side is clear form the decription, and the apearance of the second side is much like the blue side in my post above, except there is TWO emepty holes between each spoke pair, rahter than one.

This has would make all the spokes on each side of the wheel the same length, which seems like a good thing.
Had the hub 1st, then got a good deal on the rim. (nm)TFerguson
Sep 6, 2003 5:12 AM