|How true is true?||Mootsie|
Jan 9, 2002 3:11 PM
|I recently took the plunge started truing my own wheels. My question is when do you stop? How true is true? I have slight variations in the rim, but nothing close to brake pad rub. Do I stop here or do I continue until ultimate perfection is achieved?|
|I think that's a sort of sliding scale kind of thing thing.||nee Spoke Wrench|
Jan 9, 2002 3:25 PM
|On a new wheel built with good quality new components, I generally quit when I get the wheel to within 1mm in both directions. I think that it's more important to have as equal spoke tension as possible than to have absolutely no wobbles in the rim.
If I'm working on someone's used wheel that has a Weinmann 519 rim and a "pos" hub, I can't always get there.
|That silly millimeter||Kerry Irons|
Jan 9, 2002 4:42 PM
|While many perfectionists would shoot for less than 1 mm of wobble or hop, it's a reasonable target. After all, that's only 1/25th of an inch. You can easily obtain this degree of true just working with the wheel in the frame, using the brake pads as truing guides. In my own experience, eliminating hop is more important than eliminating wobble, and I absolutely agree that the goal is uniform tension (to the extent possible).|
|re: How true is true?||grzy|
Jan 9, 2002 4:13 PM
|A rule of thumb would be to stop when you feel like you're chasing your tail. Once you realize that you don't seem to be getting anywhere it's time to stop. Just where exactly is this point - it all depends. It depends on the quality of the componenets of the wheel, how thrashed it is, how tight your truing setup is, how light your touch is, how much skill/expereince you have and how much patience you have. If at the end of the day you still have brake rub then there is a problem. Possibly the ultimate setup is to get a truing stand with dual dial indicators and the DT spoke tension gauge, but you're looking at close to $1,000 in tools - none of which assures that you are capable of doing a good job. I've seen masters do beautiful work on equipment that is cobbed together and I've seen crappy work come off of some nice equipment. It really comes down to the individual. Realize that it's much easier to get all new components nice and true than some POS. the big variable is time - how much do you have?|
|whilst on the topic...||happy happy|
Jan 10, 2002 12:38 AM
|am now building a home brew wheelset of very simple specs. 36 spokes with high flange hubs and no dishing (fixed/free wheelset). 14g and 3x. whithout splurging on a tension-meter thingamajig how can i tell what is too high or low a general tension. the trueing hopping part i have found pretty atainable but i dont have a wheelset that is similar to compare as my only other wheelset is a boutique low spoke machine tensioned variety.
im of good heft and my instincts tell me tighter but how tight is too tight and after aleiving tension is riding the only way to tell?
i know its hard without generalizing and every wheel is different but its my first and as my spec is pretty simple i wanted to do it myself as an introduction with help from zinn and sheldon.
|Good question!||nee Spoke Wrench|
Jan 10, 2002 6:48 AM
|Wheelsmith says that optimum tension and maximum tension are very close. Maximum tension is the most tension that does not cause the spoke bed to crack out. So I guess that you ride on the wheels for a while and if the spoke bed starts to crack the tension was too high, and if it doesn't crack the tension was too low.
Then there's this: Lots of good wheels have been built up using Revolution spokes and aluminum nipples. Long before you get enough tension to crack a decent quality rim, you are going to start rounding out nipples or just winding up the spokes. So on a combination like this, you just tension the wheel all you can.
More realistically, I'd "feel" every good wheelset I could get my hands on to get a subjective feel for the amount of tension they used. Then I'd try to mimic that.
On a wheel that has little if any dish, I wouldn't worry too much. On the wheels that I've worked with that broke repeated spokes due to inadequate tension, the non-drive side spokes felt seriously loose.
|The things that I shoot for...||Greg Taylor|
Jan 10, 2002 6:31 AM
|My priorities when I build a wheel are (in descending order)
(1) Even Tension
(2) Proper "dish" (is the thing generally centered properly)
(2) "Round-ness" or vertical true (no "hops" in the rim)
(3) Fine tuning lateral true (side to side)
I can usually get the thing within 1mm of being laterally true, but I won't sacrifice an even spoke tension to achieve it. Grzy's advice of stopping when you feel like you are chasing your tail is very, very wise....