09-27-2020, 11:30 AM | #1061 |
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So, off topic I guess, but talk to be about the hub stands. I assume those are the Paco Moto ones.
How in the heck do you do a four-wheel alignment with those? I spent an hour yesterday doing an alignment with my DumbStrings setup (pic below), which is a $20 DIY string alignment rig that has been my go-to for the last few years. Those plus a two-post lift make for very easy and accurate alignments. I read the Paco Moto .pdf file for the hub stands and there's a bunch of "that's not right" in there so I'm curious how you managed. |
09-27-2020, 04:09 PM | #1062 |
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So the answer is probably going to bother you a bit, but basically, the thrust angle wires need to be aligned identically side to side for a four wheel alignment. You are measuring total toe with the tape measures and reference “straight ahead” off of the guides / wires.
If there are things that are basically impossible with a wheel on, it’s killer. On top of that, because you have the always there guide plate reference, you can see how much of a change you are making as you turn the adjuster. The part that is a little weird is that unless your hubs are all at exactly the same plane, you won’t actually have a square reference. You also need to get your camber precisely aligned because that will influence the thrust angle measurement.
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09-27-2020, 04:41 PM | #1063 |
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Yeah, you hit on what I was getting at.
They seem like they could be convenient for some stuff. I keep contemplating buying a set but I always end up thinking I wouldn't use them for much so I never end up pulling the trigger. |
09-27-2020, 07:41 PM | #1064 | |
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Quote:
And you don't have to tediously find level and square with the strings.
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09-27-2020, 08:50 PM | #1065 | |
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Quote:
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09-27-2020, 09:46 PM | #1066 | |
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Quote:
...and then they get jostled and I have to start over. I mean, the strings are fine. But the stands let me do things I can't do (align the 993 / work loaded with the wheels off), and I find them a lot easier to use. Edit: Also, I'm getting old, and while my eyes are sharp, my contrast vision isn't what it was. It's a lot harder to see the fishing line these days, even if my technique with the strings is a lot better than it once was.
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09-28-2020, 06:51 AM | #1067 |
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Smart strings are way too fiddly, which is why I don't use them.
I totally get the convenience of hub stands, just not for accurate alignments |
09-28-2020, 08:19 AM | #1068 |
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Genuinely curious: Why do you think that this is less accurate?
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09-28-2020, 09:11 AM | #1069 |
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Mostly due to the tolerance stackup associated with the hub stands. You're not measuring toe directly at the wheel - you're taking measurements remotely, trusting that the hub stands are perfectly true and that there's no bowing or bending or camber built into the stands during their fabrication. You're also trusting that the gradations in the stands and the tape measure slots are in precisely the same location. The manufacturer can promise that they're true, but there's really no way for the end user to verify that.
Second, you're relying on the accuracy of two tape measures and that you can repeatedly take precise measurements. Even with toe plates I've found that I have to take two measurements and average them to get a quick toe check. With strings, they are guaranteed to be parallel because the slots for the strings are cut simultaneously. They are squared on the car by measuring directly to the car (wheel, hub, however you like to do it). As long as they are level and they stay square which is dead-nuts simple, you're guaranteed an accurate measurement as long as you use a proper scale or caliper to make the measurement. |
09-28-2020, 09:32 AM | #1070 |
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Based on looking at them it's also not clear to me how they take up any track width variation, or difference in hub location from one corner to the next. But I'm probably missing something there.
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