Current Topics

Are Shims Causing a Soft Foot Issue?

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By on May 15, 2018

One of the many things I love about my job is the numerous challenges we face during the field alignment portion of our Precision Shaft Alignment Training. Prior to the training, there were some repeatability issues when attempting to perform a precision alignment on this piece of equipment. One of the main causes of non-repeatability […]

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Should Soft Foot Be Corrected in Centrifugal Pumps?

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By on March 20, 2018

  In a previous blog I wrote in Jan of 2016 “Soft Foot Concerns in the Stationary Machine?” soft foot in the pump was causing repeatability issues during a precision shaft alignment. https://vibralign.com/other-topics/soft-foot-concerns-stationary-machine/ Soft foot can also distort the pump casing which can change clearances within the casing. This can shorten the life of the […]

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The Soft Foot Primer (Part 3) How to REALLY Minimize Soft Foot Every Time

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By on March 4, 2018

It is both possible, and desirable, to minimize the negative effects of soft foot.  While it may be difficult to completely get rid of soft foot, it can typically be reduced to a few mils, if the following techniques are used. PREPARATION AND CLEANLINESS CLEAN! If you remove the motor, wipe the feet clean, before […]

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The Soft Foot Primer (Part 2) Vibration and Alignment Problems Related to Soft Foot

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By on February 26, 2018

Most industrial maintenance mechanics who are involved with precision shaft alignment are familiar with the phenomenon of soft foot.  From an alignment standpoint, soft foot causes: Changes in alignment values, between when the hold down bolts are loose, and when they are tight. Non-repeatability in alignment measurements, especially if the bolts are not tightened in […]

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The Soft Foot Primer (Part 1) Are You Measuring Soft Foot, or Just Its Effect?

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By on February 19, 2018

Most laser alignment tools include a soft foot function. However, in truth these tools haven’t measured ACTUAL soft foot, instead they have measured the EFFECT of soft foot at the shaft or coupling as that is where the laser heads or sensors are mounted.  While the EFFECT of soft foot is important, correcting the ACTUAL […]

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Soft Foot! Or Are You Just Pulling My Leg?

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By on February 12, 2018

It’s no joke that many machines operate with high levels of vibration due to soft foot.  These same machines often have a decreased life span due to this condition. Soft foot is a condition that should be eliminated during the precision shaft alignment process, if you’re performing proper alignments at all.  This condition can manifest […]

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Soft Foot Concerns In The Stationary Machine?

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By on January 27, 2016

VibrAlign has numerous blogs on soft foot and the frustration that goes along with not eliminating it. Repeatability (or the lack of) can be a major issue. Vibration analysis will pick it up if it is severe enough. When performing a precision shaft alignment most, if not all, soft foot will be eliminated in our […]

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Clean, Clean, Clean! To Eliminate Soft Foot!

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By on May 7, 2015

There are many things that can affect the precision shaft alignment process, which needs to be checked and eliminated during the Pre-Alignment Steps, such as pipe strain, disintegrating bases, bearing or coupling wear, etc…. One of the main issues concerning shaft alignment of rotating equipment is the challenge of soft foot and its detrimental effect […]

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Soft Foot And The Dirt That Causes It

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By on January 15, 2015

While on the road for VibrAlign ReAligning America, we trainers encounter similar issues at every facility where we conduct our Shaft Alignment Best Practices Training. During our training classes we ask the students what are some of the “pains” that they have regarding the precision shaft alignments that they have attempted in the past. The […]

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Combination Soft Foot?

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By on February 6, 2014

Any aligner knows that not properly correcting soft foot during a precision shaft alignment leads to frustration and anguish, not to mention wasted time. Soft foot is such a problem there has been numerous articles on The Alignment Blog the past few years about the subject. The articles discuss the many causes of soft foot […]

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Soft Foot Caused by a C-face Motor

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By on February 12, 2013

Our service group received a call from a water treatment plant in the western US for assistance to align a gearbox with C-face motor to a rotary lobe pump. After numerous failed attempts and multiple hours of frustration they had determined the gearbox to be Bolt Bound.   We were asked to bring turned down bolts and […]

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Cutting Shims to Correct Soft Foot During A Shaft Alignment

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By on August 20, 2012

Here’s a thought-provoking question for you my fellow shaft aligners: is cutting shims to correct soft foot overkill? That concern was addressed last week during a shaft alignment training class where we aligned a nice little water pump. The motor had one of the stamped out bases that are always fun to work with. We […]

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The Return of Soft Foot

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By on May 19, 2012

Previous alignment blog postings have discussed the negative effects of soft foot on rotating machinery reliability and the importance of checking and correcting soft foot before proceeding with a shaft alignment. The question is: “does soft foot need to be checked during an alignment?” Possibly. During a recent GO Pro training class an alignment check […]

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Was Soft Foot the Problem?

By on August 26, 2011

We all know what soft foot is, correct? Soft foot is when we are sitting at dinner and the table rocks. Our solution: put a matchbook, folded piece of cardboard or sugar pack under the leg that needs to be raised even with the other three. Now let’s eat dinner without our drink spilling. In […]

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Soft Foot–What It Is and How to Minimize It

By on June 4, 2010

Soft foot is a common issue when aligning rotating equipment. It is a major cause of repeatability problems in shaft alignment measurements. In addition to alignment quality and repeatability problems, it can be a cause of machinery vibration, reduce life in electric motors, and cause internal clearance problems in gearboxes and pumps. But if the […]

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