Cutting thread on spokes
 

I want to relace my front wheel radially, but I'm a cheapskate who does not want to buy 36 new spokes. I'd rather cut the existing spokes shorter and cut new thread on them. Time-consuming perhaps, but that's what hobbies are for.

Can I use a normal thread cutter, or are spoke threads rolled?

why do you want radial? whenever I see a radial wheel, I think: "that wheel is radially laced." its not a good thought.

Normally they are rolled on a threading machine. Phil Wood makes one for 3 kilobucks. Hozan has a light duty one for $100. I've used neither.

I personaly rather build a wheel with the manufactures own threads since rolled is stronger than cut ones. That being said my 4cross hardtail has a funny spoke size that DT alpines didnt come in. I cut them with a quality pair of cutters, then using a fine grit grinding wheel made the sure the end of the cut was square and free of any burs. I use a Hozan cuter at work when I have too. Make sure you have it set to propery cut the thread for the right guage (14 - 2mm 15 - 1.8mm) and use lots of lube. Setting the lenth of the cut can be a pain I use chainring spacers on the outter side of my cutter so it only threads about 9mm of each spoke before it bottoms out. Spokes break 3 ways, Head popping, nipple breaking or the spoke failing at the last thread from it not being into the threads of the nipple. If you have butted spokes your idea is useless since youll be cutting the spoke down into where it becomes narrower.

Measure twice and be prepaired to re thread a few of them. Good luck!

Let me counter with a Q: Why not?

Is your hub capable of handling the stress of radially lacing... I have seen several hubs designated as being able to withstand radial lacing with cracked flanges. Do you like having a wheel that flexes like crazy into a hard corner? If the answer to those two is "yes", proceed.

Radial lacing is actually stiffer vertically and axially. It just isn't as rigid torsionally to resist drivetrain torque. Check out Damon Rinard's wheel-deflection test and you'll see that the radial wheels are amongst the stiffest ones. In fact, the stiffest wheel in the entire test is a radially laced one (#92). Interesting to see that building radial with the spokes on the outside of the flange gives a 12% stiffer wheel than with the spokes on the inside (#94 and #95).

So, reading the last 2 replies together, the only objection is hub flange strength.

Flange strength is an issue. I have read that some manufacturers do not warrantee a hub that has been laced radially. Maybe that was for older hubs, maybe it carries through to today. Maybe best to send the manufacturer an inquiry first.

Nonetheless, spokes typically have rolled threads. I don't know if it makes a difference, but I would expect that if unless a cutting die makes good smooth cuts, you risk setting up a stress concentration that could lead to early fatigue. Spoke threads are common fatigue spots anyway (though not as common as elbows). However, if it does turn out to be a problem, you could always elect to buy new spokes later.

Another consideration is the existing spokes. If they are butted, you might end up cuting into the tapered region. This would not work. If they are straight gauge, then no problem there.

Personally, a package of 50 quality spokes from aebike.com (wheelsmith or DT) aren't that expensive - especially straight gauge. If I'm going to spend the time and effort to do the job, I want to be sure it will last.

Here, add another two (but if you think of the strength/failure/likely crash risks listed above you shouldn't really need any more):

• radial wheels are not comfortable to ride, they are very "vertically" (axially?) stiff, and offer far less ride comfort to a crossed wheel. It is quite easily discernable when you ride one. A comfy bike will be more enjoyable, and get ridden more often - which IMHO is a good thing.
• reusing spokes is a bad idea, as they have been stressed already in differing directions. They will fail faster, perhaps at an inappropriate time. Spokes are cheap - buy some new ones, build wheels and be happy.

Notably, Shimano will not warranty hubs laced radially.

Notably, Shimano will not warranty hubs laced radially.

Spokes are only stressed in tension... It's the hub-flange that gets pulled in different directions and if you radially lace a hub with little meat on the outside ring beyond the spoke-holes, the previous gouges from 3x or 4x lacing will be a stress-riser that will initiate a crack and split the flange off. Best to do radial lacing on a fresh hub only. I try to use hubs with at least 4mm of material on the outer edge beyond the holes.

If you really wanted to roll new threads, get the Hozan tool. It comes with an adustable rolling die that can roll 12ga down to 16ga. A lot of the RC helicopter/plane crowd use that tool to make their own control lines for servos. Cut a spoke to correct length, thread at both ends, then bend into the correct shape and install.

Tip for using the Hozan tool:

1. calculate exact spoke-lengths needed first.
2. cut spoke to length
3. grind tip flat, bevel 90-degree corner at tip
4. tool works best if several original threads remain to guide the roller
5. push roller down onto spoke at the same time as spinning handle

This last step is especially important if you don't have any old threads to start the roller. If have a bare end, and you don't push the roller down to onto the spoke, sometimes the tool just spins at the tip and rolls just 2-3 concentric circles on the end of the spoke, rather than a spiral thread pattern. That's where the bevel at the end helps as well, it lets the roller move down the spoke easier without having to make full-depth threads.

Another tip is to set the roller too loose for a spoke larger than you're actually rolling on the initial calibration of the tool. Then inspect the depth of the threads. Then tighten the roller a little more and roll again. At some point in the adjustment, the fresh rolled threads will be at the same depth as the original. Pull out a Sharpie marker and draw a line across the adusting nut and roller so that you can keep that position for that size spoke. This initial adjustment is important to make sure the roller lasts. If you set it too tight initially and force it onto a spoke that's too large for the setting, it will destroy the roller on the very first spoke you try to cut...

I've got the Hozan, and it does a decent job. You can't thread a spoke with a die, they have to be rolled. The threading process removes material when the threads are cut. If you know the exact length of spokes you need, let me know and I'll see if I can get you a deal on them.

There is no more crash risk associated with breaking out a flange hole and a simple spoke failure. Unless the wheel goes so far out of true that is locks up against the fork (highly unlikely - especially with a 36 spoke wheel), you would still have control of the bike.

I doubt that the wheel lacing has any significant effect on the harshness of the ride. I have a bike with a radially spoked front wheel and I've ridden it thousands of miles without comfort issues.

There is no basis for a claim that reused spokes will be stressed differently than new ones. Spokes are tensioned at the endpoints and all stress is along the line between those points. Although a cross laced wheel does put a slight bend in the spokes where they cross, spokes never break in the middle unless defective or damaged, so this would certainly not be a factor. Certainly, going to a radially laced wheel would remove this trivial bend anyway which could only increase the service life of the spoke.

But you would probably have to walk the bike home, and then replace the hub, which is pretty expensive compared to the minimal advantages radial lacing can offer.

I have a cheapish one. I think that it's a Hozan but I'm not sure. It sits firmly esconced at the top of my list of tools that I would never buy again. You can buy a lot of spokes for what one costs and it simply isn't up to the task of making threads on stainless steel spokes.

IMHO: Radial wheels are about style without any serious benefit, and substantial risks to your hub. This makes them silly. Plus, I don't think that they look very good.

Now radial TWIST on the other hand... they look awesome enough to justify any weaknesses in the build.

Really, after 15 years as a mechanic, I find it hard to believe that posters think that:

1. re-rolling threads on used spokes is a good idea
2. radial spokes don't offer a harsher ride

I can understand that radial spokes might look cool to some (beauty is in the eye of the beholder) and may be lighter - but they are harsher - ride one.

Anyway, radially spoke yourselves senseless - but just buy some new spokes (or if you can't get the right length - roll threads on new spokes).

Use old spokes again, and you will not be happy when a rebuild comes around far quicker than you'd like. Rebuilds are expensive - and you'll be buying new spokes then.

Rant over ....

Ooops, ride one AND COMPARE.

How are the original threads created?

I have both types of laced wheels - one 3x, one radial (Shimano R500). They have the same tyres and are pumped the same pressure. I can't discern ANY difference in harshness. I think this whole harshness issue (frames included) is in some part myth, your 15 years notwithstanding. There is good solid reasoning behind this opinion. No offense meant. :)

I would not hesitate to re-roll threads on my spokes, the ones I mean are in fact brand new since I replaced the front wheel just this past weekend.

BUT since I don't have access to a thread roller, the whole question is moot. The wheel will remain 3x or I will buy a packet of spokes if I can convince myself the hub is good enough for the job.

Thanks very much for all the info. :beer:

Don't do it! I've seen an accident on the velodrome caused by a flange cracking on a radially built front wheel. Cracked pelvis, much dental work, collarbone tendons snapped, wrist broken, knee wrecked. Radial may be pretty but the risk isn't worth it. I build wheels professionally and would only now consider radial on rear non-drive side if client insists and the hub is trustworthy. Never use old spokes. They have been loaded and unloaded thousands of times in their lives and if they are not built tight enough will eventually fail, especially if they are not a tight fit in the flange hole.

One correction: the Hozan tool DOES NOT CUT threads, it ROLLS them. Cutting involves the removal of material. Do you have any shavings after threading with the Hozan? No. (but if you do, then something is critically wrong with your threader/technique.)
The only thing you could fault the Hozan with is lower-quality rolling heads, which will wear out faster than the $3K Phil tool, but it is adequate for occasional use if used carefully.

Look for a bike shop that has a Phil Wood spoke roller/cutter.

When you find some bike shops that have one, whittle your list down to shops that also have a sizercycle (or some type of geometry adjustable sizing contraption). If you find a shop that has both, you've found a great LBS. Give 'em your business for life.

Avoid all the off-the-shelf bike shops that don't have such a sizing device. They have team meetings about how best to say "that bike looks like a good fit" to any bike in inventory, and they also train on how to sell what's in stock rather than what the customer wants.

A shop that has a Phil Wood spoke roller is the real deal. You should be able to get your spokes shortened for radial use for a nominal fee.