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Dial indicators work, but when a customer requires documentation laser alignment is the way to go. The company I work for has a laser alignment tool for shaft alignment. Most of our trucks have Pulley Partners for Pulley and belt alignment. The laser shaft alignment tools are not cheap, I think around 5k for a cheap one and like 15k for the high end if not more. With a laser alignment you have a calibrated instrument to tell you you have it right. When we higher a vibe and alignment company they use a laser alignment, but also have dial indicators to check run out.

Originally Posted by double bogey

This, it really suprised me when a coworker showed this to me. Shook my confidence with the dials.

Why would it be an issue? Sag is nothing but a natural force that's going to be repeatable if the setup is the same. Simply set your indicator up on a piece of pipe or shaft over the same span as your work will be done, zero, roll 180°, read the sag, compensate at 12 o'clock before starting your vertical parallel reading and read 6 o'clock directly. Longer the span, worse the sag. If you test the runouts on all parts and they're within tolerance, then the only part of the process that sag is an issue for is the vertical parallel. Sag is the reason that I use face and rim instead of reverse indicator. Easier for me to deal with in that manner.

Originally Posted by double bogey

This, it really suprised me when a coworker showed this to me. Shook my confidence with the dials.

well my friend, the laser is also prone to sag and one of the first steps for indicator or laser alignment is to compensate for sag, around -2 mils, I blame gravity for it.

Originally Posted by Tommy knocker

You really can't go wrong with the thumb up, left eye closed method.

Yup

Originally Posted by Tech Rob

If you zero it at the top, I think it'll read sightly negative on the bottom of the shaft due to sag.

This, it really suprised me when a coworker showed this to me. Shook my confidence with the dials.

Originally Posted by double bogey

Just for grins, take a shaft and fix your indicator to it. Zero the indicator and then turn the shaft over and see what it reads.

If you zero it at the top, I think it'll read sightly negative on the bottom of the shaft due to sag.

Pictures and/or videos would be nice.

Just for grins, take a shaft and fix your indicator to it. Zero the indicator and then turn the shaft over and see what it reads.

I use a good ol stick rule on belt drive units.. I teach the newbies the 4 point rule on straight edges and use dial for the big boys... Everyone is correct when they say it is a dying art. I only do about twice a decade, which makes for a poor showing on my part.

You really can't go wrong with the thumb up, left eye closed method.

Originally Posted by double bogey

The outfit I used to work for needed documentation on a couple of jobs so we bought a laser alignment setup. You could learn to use it in about half an hour. I brought a class in on a Saturday and trained them how to use dials (we had a pump on a base). Once they got a handle on that we broke out the laser. All picked it right up. After that our young guys who went to the class could run rings around the guys who didn't want to learn the laser. It also provided printable documentation of the alignment.

all the laser systems are based on reverse dial alignment, I've never use the laser but I see guys using it and its pretty simple, straight forward system, the computer tells you what size shim and where to put it, the only reason I still use indicators is money, the laser cost 10 times or more the price of the dial indicator setup, I also think that by dummy down our trade we are shooting ourselves on the foot.

The outfit I used to work for needed documentation on a couple of jobs so we bought a laser alignment setup. You could learn to use it in about half an hour. I brought a class in on a Saturday and trained them how to use dials (we had a pump on a base). Once they got a handle on that we broke out the laser. All picked it right up. After that our young guys who went to the class could run rings around the guys who didn't want to learn the laser. It also provided printable documentation of the alignment.

Originally Posted by klove

I could say something really snide like, "I don't think we could cover it all in two days", but I won't (Hey - you opened the door)

You're probably right.

Originally Posted by klove

I could say something really snide like, "I don't think we could cover it all in two days", but I won't (Hey - you opened the door)

I just think that folks rely too much on technology nowadays. Not that it's bad, but the "old" way of doing things had a chance to get old for only one reason - it worked and was used long enough to get old. I've dealt with large gear for a long time, and remember talking to some guys that were old when I was a kid that used Yankee calipers and feeler gauges to align stuff, and it ran just fine with no premature failures.

As far as my comment about alignment taking more than most folks are aware of to get it done correctly, if you're competent or better with dial indicators, ask 20 techs if they can do alignment work. They'll all say yes. Then ask them to explain what to do from start to finish and see how many know their butt from third base....

Old things may have got old because new technology was not born yet. I agree with you though and many of my co workers would too. That being said I do not have the new technology but I do have "yankee" calipers. They are really hard to find nowadays! I would love to score a garage sale starrett. I couldn't tell you how to line up though I'm bad at explaining but I could do it.

Originally Posted by Tech Rob

Maybe I can come work with you for a couple of days so I can see everything I am doing wrong?

I could say something really snide like, "I don't think we could cover it all in two days", but I won't (Hey - you opened the door)

I just think that folks rely too much on technology nowadays. Not that it's bad, but the "old" way of doing things had a chance to get old for only one reason - it worked and was used long enough to get old. I've dealt with large gear for a long time, and remember talking to some guys that were old when I was a kid that used Yankee calipers and feeler gauges to align stuff, and it ran just fine with no premature failures.

As far as my comment about alignment taking more than most folks are aware of to get it done correctly, if you're competent or better with dial indicators, ask 20 techs if they can do alignment work. They'll all say yes. Then ask them to explain what to do from start to finish and see how many know their butt from third base....

Originally Posted by klove

..........Only problem with using dials for alignment is that there's far too many techs nowadays, and far too few mechanics left.....

Yup, yup and more yup.

For shafts, a dial can give you a zero point, a circular run-out interpolation and a true RMS deflection value IF you know how to apply the formulas.

FWIW my guys use a calibrated Belt Hog with great results.

Originally Posted by klove

How can you say that laser trumps dial and that you need to be taught to use a dial, all in the same sentence? I beg to differ that anything is better than a properly used dial setup. Might be as good, but I doubt better. Been using dials for 30 some odd years now and never been let down yet. It just takes far more to do it correctly than most folks are aware of. Use a 6" straight edge and LED flashlight on soft couplings, string on belt drives.

Only problem with using dials for alignment is that there's far too many techs nowadays, and far too few mechanics left.....

Maybe I can come work with you for a couple of days so I can see everything I am doing wrong?

Originally Posted by fitzyfitta

My shop has been using a laser alignment tool for years on new pump's and replacements. Also has a laser tool for sheave alignment. I wish I was taught how to use a dial indicator but the electronic trumps it. I really would like to see an affordable laser tool for sheave/pulley alignment. You would think with the technology out there they would be sold at any hvac supply house. I've also used the laser pen before. It's a good, cheap alternative. FITZ

How can you say that laser trumps dial and that you need to be taught to use a dial, all in the same sentence? I beg to differ that anything is better than a properly used dial setup. Might be as good, but I doubt better. Been using dials for 30 some odd years now and never been let down yet. It just takes far more to do it correctly than most folks are aware of. Use a 6" straight edge and LED flashlight on soft couplings, string on belt drives.

Only problem with using dials for alignment is that there's far too many techs nowadays, and far too few mechanics left.....

Started reading about reverse alignment tonight.... I will have to pick it up again tomorrow. Not the most exciting read near bedtime.

My shop has been using a laser alignment tool for years on new pump's and replacements. Also has a laser tool for sheave alignment. I wish I was taught how to use a dial indicator but the electronic trumps it. I really would like to see an affordable laser tool for sheave/pulley alignment. You would think with the technology out there they would be sold at any hvac supply house. I've also used the laser pen before. It's a good, cheap alternative. FITZ