Cracked Flange Repair?

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Bridgeman
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by Bridgeman

As you can see in the photos, I have a cracked hub flange. Question is, anyone repair a crack like this?

I'd like to keep these Reynolds MV32 Tubulars as backup wheels. I have 2 ideas for repair that would provide a fairly high degree of structural integrity. It won't be pretty though.

Image
Image

by Weenie


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Calnago
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by Calnago

Looks like toast to me, but I'm curious about your ideas to fix it?
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TwiggyTN
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by TwiggyTN

Uh, no. Sorry, that's dunzo.

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Bridgeman
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by Bridgeman

As is, you guys are right, but I just put new bearings in these hubs! On a more serious note, maybe just for the challenge.

How about drilling a new spoke hole to the left of the original and adding a slightly longer spoke? There is clean real estate there.

Afterwards I would carry on with fortifying the cracked section, which will curtail its propagation.

Marin
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by Marin

New hub, new spokes. There's no economic way to repair this.

Butcher
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by Butcher

If it can be repaired, the time and effort needed would far outweigh the the cost of another hub [used or new].

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F45
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by F45

If you were handy with a tig welder, you could do it, but paying a skilled welder is going to be expensive.

I've wondered why builders put the trailing drive side spokes on the inside of the flange. The bracing angle is less so they require more tension than the other side, then they get stressed more under load.

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Calnago
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by Calnago

F45 wrote:I

I've wondered why builders put the trailing drive side spokes on the inside of the flange. The bracing angle is less so they require more tension than the other side, then they get stressed more under load.

Mostly to lessen the chance of the spokes, where they cross, from interfering with the rear derailleur when it's on the largest cog. In this instance, under load, the pulling spoke will tend to force the spoke it crosses inward rather than outward. It's more of a factor if you're using thicker round spokes than a lot of today's bladed spokes. Also, if you think about it, at the final spoke crossing point the bracing angle is actually greater from that point to the rim for the spoke on the outside, regardless of which side of the flange it started from, however minor that difference may be.
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Cleaner
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by Cleaner

Contact DT Swiss and ask them if they can help you out. I have had good support from them on three hub failures. One was a MTB hub replaced with a cracked flange.

Bridgeman
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by Bridgeman

The wheels were built in late 2007, so the rims are pretty much gone. The cheapest thing to do would be to buy a better used set on ebay for a backup wheelset. I was hoping to eek out this winter season with these, until I track down a replacement set.

I'll contact DT Swiss and see what they say. If it doesn't work out with them then I'll work on this until I locate the new set. First I'll try moving the new spoke hole and replace the existing spoke with a longer one. Next I'll drill and tap for at least one 00-90 screw, and close the crack. Won't cost much at all. I'll post when I'm done.

Thanks for your thoughts!

Svetty
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by Svetty

From the first picture it looks as if the crack extends into the neighbouring spoke hole so moving the one spoke as you suggest isn't likely to work I'm afraid. :-(

Bridgeman
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by Bridgeman

Yes, the cracks seems to have propagated into the next hole, at least on one side.

I have a solution that will contain this crack and keep the existing spoke holes as usable, with not much effort.

Geoff
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by Geoff

Hmmm. That looks familiar. Unfortunately. That hub is garbage.

9tarmac
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by 9tarmac

Invest your repair money into a new set. Sad decision but been down this road recently myself.

Bridgeman
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by Bridgeman

Yes, ebay is my friend. I'll locate a good second wheelset.

This is just a little challenge project. No money involved.

Pics when completed.

by Weenie


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