Is this wheel tensioned good?
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So, I other words, you want the tension variation to be within 5%?
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Yep, if possible.
What spokes are you using? I'm not familiar with any that read that low on a park tension meter and convert to ~120 kfg.
I am using cx-ray spokes
Well I am not sure where to start, but I will use tension meter to get all spokes the same tension (13.5 for high tension side, 7 for low tension side), then I will see how the wheel spins and try to true it from there. Not sure if thats the correct way but I will try it
Well I am not sure where to start, but I will use tension meter to get all spokes the same tension (13.5 for high tension side, 7 for low tension side), then I will see how the wheel spins and try to true it from there. Not sure if thats the correct way but I will try it
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1.5mm spoke i
You need to be careful, just evening out the tensions blindly will lead to a wonky wheel.
You need to be careful, just evening out the tensions blindly will lead to a wonky wheel.
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Did a long write-up, but in summary... check where the biggest "jump/drop" in tensions are... depending on the rim's build quality from the factory, you often may find this at/across the joint (obviously not for carbon rims, but for aluminum/steel)... the better the rim quality up front (you didn't mention model) the less likely a problem, but it CAN happen...
If the rim wasn't welded/pinned "square" properly, you'll never get even tension in that area, you just have to do best-effort. (For instance, the joint "angle" at attachment, may have been slightly less round/more round on each side, so the total joint will never be perfectly aligned with the intended diameter, and/or it could be shifted slightly left/right at that joint, again, same problem, the rim edges will never be quite true going into/out of that area without abnormal spoke tensions.)
Only way to test this is to de-spoke the rim and lay flat on a surface like glass, and look for a distinct bump/dip around the weld for side-true, and a rolling jig that can hold the wheel stably vertically while a height-gauge compares the opposite side (looking for anywhere it has a distinct dip/bump, of course it the joint is bad enough, it might be visible even just sitting vertically).
IF the entire rim has a "wave" to it, or is slightly oval, that doesn't matter as spoke tension will easily true that up, it's only the very short-range changes (couple of spoke holes distance out of alignment compared to the neighboring areas) that are going to be challenging for tensioning to fix evenly, those should only exist around the joint, or something bad has happened to the wheel (can sometimes be "hand-pressed with experience" back into shape in non-joint areas, but at the joint, is not easily fixable once it leaves the factory without risking breaking the joint).
If the rim wasn't welded/pinned "square" properly, you'll never get even tension in that area, you just have to do best-effort. (For instance, the joint "angle" at attachment, may have been slightly less round/more round on each side, so the total joint will never be perfectly aligned with the intended diameter, and/or it could be shifted slightly left/right at that joint, again, same problem, the rim edges will never be quite true going into/out of that area without abnormal spoke tensions.)
Only way to test this is to de-spoke the rim and lay flat on a surface like glass, and look for a distinct bump/dip around the weld for side-true, and a rolling jig that can hold the wheel stably vertically while a height-gauge compares the opposite side (looking for anywhere it has a distinct dip/bump, of course it the joint is bad enough, it might be visible even just sitting vertically).
IF the entire rim has a "wave" to it, or is slightly oval, that doesn't matter as spoke tension will easily true that up, it's only the very short-range changes (couple of spoke holes distance out of alignment compared to the neighboring areas) that are going to be challenging for tensioning to fix evenly, those should only exist around the joint, or something bad has happened to the wheel (can sometimes be "hand-pressed with experience" back into shape in non-joint areas, but at the joint, is not easily fixable once it leaves the factory without risking breaking the joint).
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Is there good method to relieve stress during the build process?
If not done during the wheel process, can it be done after the fact. Ie, ride for a few miles and re-tension?
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It would help if we know what rim and hub combo you are using. I am guessing a carbon rim given 24 spokes, but am surprised the low side tension is so low, you don' usually see them that low any more.
My two cents. Don't worry about perfect true. Get your tension as even as possible while maintaining a reasonable true. I personally don't worry about 1-2 mm of runout in either direction, we don't ride rim brakes anymore where getting that last bit of trueness affects the ability to adjust the brakes for best performance. Also, in my experience, carbon rims tend to hold their shape. If they laid up perfectly true, they will easily build perfectly true. If they are slightly out, it take a lot of uneven tension to get them to true.
I would back your tensions off to about 1/2 where you are now, get them even, then check true and tweak that slightly. Then bring up to tension, first 1/2 a turn at a time, then a 1/4 turn at the end while stress relieving. Also, don't be surprised if you need a bit of wicking Loctite (220) for the low side nipples to keep them from backing out while riding.
My two cents. Don't worry about perfect true. Get your tension as even as possible while maintaining a reasonable true. I personally don't worry about 1-2 mm of runout in either direction, we don't ride rim brakes anymore where getting that last bit of trueness affects the ability to adjust the brakes for best performance. Also, in my experience, carbon rims tend to hold their shape. If they laid up perfectly true, they will easily build perfectly true. If they are slightly out, it take a lot of uneven tension to get them to true.
I would back your tensions off to about 1/2 where you are now, get them even, then check true and tweak that slightly. Then bring up to tension, first 1/2 a turn at a time, then a 1/4 turn at the end while stress relieving. Also, don't be surprised if you need a bit of wicking Loctite (220) for the low side nipples to keep them from backing out while riding.
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"Stress relieving to relax these high stress points is accomplished by over-stressing them in order to erase their memory. It is not done to bed the spokes into the hub, as is often stated. Bedding-in occurs sufficiently from tension. However, stretching spoke pairs with a strong grasp at mid-span, can momentarily increased tension by 50% to 100%. Because spokes are usually tensioned no higher than 1/3 their yield stress, this operation has no effect on the spoke as a whole, affecting only the small high stress zones where spokes are near yield. By stretching them, these zones relax below yield by as much as the overload.
Stress relieving with a light grasp of spoke pairs is worthless, as is bouncing the wheel or bending it in a partially opened drawer. Pressing axially on the hub, while supporting the rim, requires a force larger than is manually possible but is effective for spoking machines (except the left side rear spokes that would collapse the rim). Another not recommend method, is laying the wheel on the floor and walking on it with tennis shoes, carefully stepping on each pair of crossed spokes. The method works but bends the rim and is difficult to control.
It is STRESS RELIEVING! Even though people insist on calling it pre-stressing or seating-in. The wheel is already prestressed when tensioned.
Jobst Brandt"
It is done by simply putting on gloves and grabbing each parallel set of spokes and giving them a hard squeeze. Just work your way around the wheel doing them as you go. Take all of 30 seconds.
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FWIW I use a wood dowel and twist each pair of spokes together with steady force then release. Then I recheck true and see where I'm at. It has worked well for me thus far - my builds have stayed true and tight.
Ok the truth is I am using chinese hubs (ztto R2 road hubs) and chinese carbon rims (25mm width 50mm deep 24 hole), also using chinese CN-MAC 424 Aero Spokes (same specs as cx-ray), I didn't want to mention that because I think true wheel builders hate to hear it lol but since its my first wheel build I decided to go cheap.
I am using a bladed spoke holder as I turn the nipples, i am pretty sure there is little to no wind up and there is no stress to relieve but I still am doing the methods I find online to relieve the stress but after I do it I notice no difference in how the wheel spins.
I am noticing its the spokes near the valve hole that seem to need more tightening on one side, I will just assume since these are cheaper price rims they do not have the top quality and I guess I need to add a tad bit more tension in that area.
I just finished up building the wheel again and it turns out better this time, I probably did not need to do all this work I should have just loosened the spokes that were too tight and went from there but honestly I still need more practice building wheels since this is honestly my first one and I am happy with the results to be honest, here is the new tension graph
![Product Slope Rectangle Font Parallel]()
I am using a bladed spoke holder as I turn the nipples, i am pretty sure there is little to no wind up and there is no stress to relieve but I still am doing the methods I find online to relieve the stress but after I do it I notice no difference in how the wheel spins.
I am noticing its the spokes near the valve hole that seem to need more tightening on one side, I will just assume since these are cheaper price rims they do not have the top quality and I guess I need to add a tad bit more tension in that area.
I just finished up building the wheel again and it turns out better this time, I probably did not need to do all this work I should have just loosened the spokes that were too tight and went from there but honestly I still need more practice building wheels since this is honestly my first one and I am happy with the results to be honest, here is the new tension graph
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Looks better. What are you trying to correct for on spoke 2? It looks like you are trying to pull it into true, but how close? Whether using the cheapest or most expensive components, the building technique is the same, it just may be you need to allow a bit more runout to get more even tensions.
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This is one of the best posts I have ever read on this progressive socialist website.
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Just trying to be a good commie.
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