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I recently purchased a Park Tool TS-2.2 truing stand, however I feel that the calibration is off. I have a wheel that was recently trued at my LBS and there is a significant gap between the rim and the caliper on the right side.

Assuming a trued wheel is on the stand, shouldn't BOTH calipers be set so that they meet the rim at the same time? I assume the point to having calipers on both sides is so that you can true both sides of the rim at the same time, right? Is it most likely the calipers are off or the arms that hold the wheel off?

Has anyone came up with a cheaper way to calibrate these things? I think it is ridiculous how much Park Tool wants for their centering tool... enter image description here

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  • First, verify that your wheel is properly "dished" with a straight-edge and ruler. Then, calibrate the stand if needed. Jan 6, 2017 at 20:11
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    (I'll note that many stands are not self-centering -- you have two different bolts to tighten against the left and right sides of the axle, and centering will be determined by which bolt you tighten the most. Your picture does not show the axle clamping bolts.) Jan 6, 2017 at 20:19
  • This stand isn't self-centering? Jan 6, 2017 at 20:21
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    And stupid question: If you remove the wheel and flip it right-for-left, is the gap still on the right side? Jan 6, 2017 at 20:25
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    Just an FYI, even park says that you shouldn't trust their truing stands for verifying wheel dish. They try to get it pretty good, but still insist you should use a dish stick to verify centering. Jan 7, 2017 at 22:03

3 Answers 3

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The 2.2 is not for directly measuring dish, a shop will use a proper dish measuring tool(for time and repeatability) and there are techniques for the home gamer that lacks a dish tool that involve flipping the wheel over in the stand and noting the difference. The caliper is for measuring lateral warp or wobble and radial eccentricity(wheel hop) Only one side of the caliper is needed at any one time, the reason the 2.2 has two sides is that it is sometimes more convenient to adjust to the left and other times to the right especially if you want to improve a slight dish issue while straightening a wobble. Also some folks like to work from the high spot side and others prefer the low spot side. In the high production shop I worked (I'd do about 40 rims per shift, and there were 4 wheel stations) we often bungeed, or jammed with a small wrench/stick, one side of the caliper wide open to make inserting the wheels faster.

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    But when one is truing a wheel it's convenient to have gauges on both sides which adjust in synchrony, so that one can adjust first one side, then the other, and easily judge progress. Jan 11, 2017 at 22:25
  • The rim width is fixed, adjusting the spokes of one side will move both faces of the rim equally. In other words, moving the rim 1mm toward the left caliper is the same as moving the rim 1mm away from the right caliper. The side to choose is often only a matter of random chance, although in a few cases a rim may have a lump on one side(often at the joint in new rims, or in old rims a kink or dent from damage) that is not a effected by truing with spoke tension and you would want the caliper on the opposite side to avoid excess contact between the caliper and the lump.
    – Max Power
    Jul 13, 2018 at 1:29
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The Park centering tool is just a symmetric piece of metal that fits into the truing stand. If you have a true wheel you can use that just as well. If you are concerned about the dish of the wheel, flip the wheel to make sure it doesn't matter which way you put it into the stand.

The centering can be adjusted with the caliper arm lock nuts (according to Park this should only be done if you're moving by 3 mm or less). These are the silver colored nuts at the base of the caliper arm visible in your photo. To adjust them loosen one side and then tighten the opposing side by an equal amount. Do this in half or quarter turns.

See the instructions at Park Tool's website for pictures and more information: http://www.parktool.com/blog/repair-help/ts-2-2-and-ts-2-centering

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I have the Park TS2.2 for home use and out of the three total of these jigs I have used, two consistently need recalibration for every wheel-given the Park calibration tool does not correspond to my axle widths (never mind rim ones) and any movement of the calipers seems to throw centering out,requiring constant movement of the sliding calipers to compensate-I now have an engineering company making me a calibration tool to my axle/rim specifications- the Park dishing tool is again very annoying to use having a poor quality dropping slider which is difficult to use and constantly drifts-therefore I prefer to achieve dish in the jig and verify only with the dishing tool.

Following on from this..the new tool is a replica of the Park tool but with 145mm axle and 35mm rim widths...have now found that the screw-thread in the caliper adjusting knob is loose thereby enabling excessive play and destabilising the calipers once trued...so now have an engineering company rectifying this issue.

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  • Can you please add a photo of your calibration tool?
    – Criggie
    Oct 2, 2017 at 19:25

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