Spoke tension meter question

[Indurain]

I am checking the spoke tension on a pair of wheels I have with a Park spoke tension meter. I noticed that on the rear wheel (driver side) that there are different tensions for the spokes that cross underneath vs the ones that cross over the top of another spoke (2 cross pattern). Is this normal? Or should I be retensioning the spokes so they are exactly the same regardless of the cross over position?

 

[180mmCrank]

I would drop RDV4ROUBAIX a PM and ask him directly ... he builds wheels for a living.

I wouldn't mess with spoke tension unless you know what you are doing.

 

[RDV4ROUBAIX]

To save a little space in my PM box I'll just answer it here.

When you're close to final tension the difference in deflection readings on your gauge between crossed spokes usually reads at about .10–.15mm, find a happy midpoint like .5

If building an aluminum rimmed wheel you'll usually get varying kgf numbers with the two spokes next to the seam of the rim, just get it as close as possible to the rest while keeping everything nice and true. Remember, as you start to build tension attend to whatever is worse. You can have even tension, but need some vert or horizontal truing and visa-versa, the trick is to make those finite adjustments towards final tension to even all that out.

 

[on3m@n@rmy]

To save a little space in my PM box I'll just answer it here.

When you're close to final tension the difference in deflection readings on your gauge between crossed spokes usually reads at about .10–.15mm, find a happy midpoint like .5

If building an aluminum rimmed wheel you'll usually get varying kgf numbers with the two spokes next to the seam of the rim, just get it as close as possible to the rest while keeping everything nice and true. Remember, as you start to build tension attend to whatever is worse. You can have even tension, but need some vert or horizontal truing and visa-versa, the trick is to make those finite adjustments towards final tension to even all that out.

Not sure I understand... for a happy medium of 0.5 in your deflection example (.1-.15) does that mean you'd be looking for something around 0.125 (or halfway between)?

Just curious about why expect varying kgf numbers around the seam.

To even things all out (horiz and vert truing) I've noticed that to work a slight ovalized wheel (that has even tension on spokes) into a round wheel I'd sometimes have to put more or less tension on the spokes, instead of even tension. So I guess that is normal??? I thought I might be doing something wrong but as long as I had a round and true wheel I didn't worry about it.

thanks for the advice.

 

[RDV4ROUBAIX]

Not sure I understand... for a happy medium of 0.5 in your deflection example (.1-.15) does that mean you'd be looking for something around 0.125 (or halfway between)?

Correction, .05mm deflection. Haven't used my tensiometer in a while for spoke to spoke readings, had to actually look at my kgf chart for this, I usually go by tone, F#, DING! Keeping in mind that on most tensiometers 1mm represents .01mm in deflection which is why all come with a chart for kgf conversion.

Just curious about why expect varying kgf numbers around the seam.

It usually reads higher because most alloy rims also are held together with a sleeve at the joint which makes that area a little harder than the rest of the rim.

To even things all out (horiz and vert truing) I've noticed that to work a slight ovalized wheel (that has even tension on spokes) into a round wheel I'd sometimes have to put more or less tension on the spokes, instead of even tension. So I guess that is normal??? I thought I might be doing something wrong but as long as I had a round and true wheel I didn't worry about it.

thanks for the advice.

Your main goal is obviously a true wheel, but to stay true you need even tension. When you're working on an egg or ovalized wheel you first need to make a critical decision whether it's fixable or trueable, sometimes you just need to rebuild. I think with the OP we're talking about a new build, but I'll continue. To work an oval back to round you need to over tighten the high points and loosen the low points. Once the rim is visually round again bring back to tension while keeping it round. Cannot compromise tension for trueness. Uneven tension makes for a weak wheel.