Category: Safety

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Automatic wheel balance

Balancing tires

I have dealt with many different ways to balance tires since I started mounting my own tires several years ago. I have had very good results using a simple bubble balancer and lead weights clamped to the rims.

I have considered purchasing a spin balance machine on several occasions but the cost of the machine has deterred me considering the small number of wheels I balance in a year. I can pay to have several tires balanced for the cost of a machine. Also, for most tires my bubble balancer provides acceptable results.

I have studied various methods of automatic wheel balancing for years as well. As the tire wears, the balance changes. And short of taking the tire off the Jeep and rebalancing it, there is nothing else that can be done using the clam on wheel weight method.

I have looked at the rings full of mercury that bolt on the back of the wheel. I have studied the sand and ceramic dust methods used on semi trailer tires. However the simplest method for me to implement would be to add a liquid to the tire.

Looking at the mathematical proof of the physics behind the sand method, I theorized that any fluid would do the same. The material tends to move to the light spot as centripetal force takes over automatically balancing the tire as it rotates.

This week I came across the idea test subject. In the past I was fighting other vibrations at the same time such as bad bearings or U joints. This time however, my truck was running smooth and I had a tire with a big chuck of rubber missing.

Running the tire with no weights produced a huge bounce that could be felt at speeds over 40mph. The Jeep was un drivable at over 60MPH.

The first test was to balance it with conventional lead weights in the bubble balancer. It took slightly over 280 grams of lead on the rim to balance the tire. It was difficult to get that much lead on the wheel and on the test run one of the weights came off. However it did produce a smooth ride.

The next test was to replace the lead with a liquid. I did not want to use water as in freezing conditions it would make a block of ice in the low part and create a huge imbalance. I chose instead a 50/50 mix of antifreeze and water.

I popped the bead on the tire and poured in 290 grams of the balancing liquid. I remounted the tier and took it for a test run.

The initial test run showed a nice smooth ride. I was not able to exceed 60MPH on the test run due to road and traffic conditions but the ride was noticeable smoother than with the lead weights.

I plan to further test the liquid wheel balancing method to see if it will automatically balance all wheels. The math shows that it will work with tires that have dynamic balance problems as well. I can’t deal with these on my bubble balancer so if the liquid method of automatic wheel balancing works, I will not ever have to buy a balancing machine.
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How to replace the AC compressor on a GMC 1500

How to replace the AC compressor on a GMC 1500, 2500 or 3500

Replacing the AC compressor on a GM 350 engine is not nearly as hard as it looks. The compressor is held to the engine by an aluminum cradle. The cradle does not have to be removed to replace the compressor. There are simply three bolts that hold the compressor to the cradle that have to be removed.

Note that this procedure only covers the physical swap of the compressor, not he associated tasks related to servicing the AC system after a compressor failure.

Begin by removing the freon from the system. If you want to have it reclaimed, take it to a shop that does this.

Remove the two electrical connections to the compressor.

Next remove the freon lines form the back of the compressor. The manifold is held in place by a single bolt. Mine was 15 MM.

Use a pry bar to move the belt tensioner and slide the belt off. I found the easiest pulley to get the belt off of was the smooth idler below the compressor.

With the freon lines out of the way, the bolts are much easier to access. There are nuts on the back and the bolt heads are held in place by a boss on the front. Mine were 9/16”.

With the nuts removed the bolts can be pushed out the front. However, it appears that they will not clear the clutch. However, there is a flat cut on each bolt. Rotate the flat to be next to the clutch and the bolts will slide out. A pry bar can be used to get just a little extra clearance if the bolt does not slide past easily.

On mine, one bolt also interfered with the fan shroud. I found that by removing the bolts that hold the shroud to the front header, the shroud could be moved enough to get the bolt out.

With the bolts all out, the compressor simply lifts out of the cradle.

With the compressor out, I had to swap a pressure switch that did not come with my replacement compressor. This switch is held in place with a snap ring.

Before attempting to slide the new compressor back into the cradle, take time to tap the bolt hole inserts all the way to the back of the cradle. This will make inserting the new compressor much easier. They will press back into the proper place when the nuts are tightened.

Slide the bolts back in by again aligning the flat spot on each bolt with the clutch and slide it in. Place the nuts on each bolt and tighten.

Reconnect the electrical connections to the compressor.

Secure the fan shroud.

Make sure the belt is routed correctly and use a pry bar to move the tensioner and slip the belt back in place.

Add the proper amount of oil and reattach the freon lines to the compressor.

You can now have the system serviced and the freon replaced.

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How to write safety procedures everyone will follow

Considering Personality Types in Safety Procedures

People are different. Every one looks at life though the lens of his own personality type. By addressing these different personality types, we can create procedures that every one will follow.

Carl Jung defines four different personality types: Feeling, Thinking, Sensation and Intuition. Most personality psychologist use four similar categories, but with different names.

Since Sensation personality types tend to be good at accounting, care taking, collecting data organizing and supervising, they tend to end up in supervisory positions. Since they themselves are good at following directions they often think others are as well. They often don’t understand people who don’t follow instructions. After all, Sensation people follow instructions simply because the instructions are there.

Sensation personality types will not normally question the procedure; they simply want it to be executed fairly and consistently. If you are inconsistent in your enforcement, sensation personality types will follow the procedure simply because it is the procedure. But, if you change the procedure, you better give them some time to prepare as they also like to plan ahead.

Feeling personality types are good at being cooperative, mentoring, teaching and training. So these are the ones you want to use to present the new procedures to the people. They will be more interested in how the procedure makes them feel than what it is accomplishing. Also, in presenting procedures to Feeling personality types, it is important to recognize them as people first and employees second. Adding some fluff to the procedure that recognizes their humanness will win over the feeling personality types while annoying the thinking personality types. So be careful to find a balance.

Thinking personality types will want to know why. They will also be the ones to suggest a better way. Be sure you listen to them. Even if you don’t implement their suggestions, be sure you listen to them if you want them to follow your procedure. Make sure the procedure explains why the procedure is important to the process and how you came up with it. These explanations are very important to Thinking personality types.

Intuition personality types are the ones who pride themselves in not following the rules and can be the biggest challenge to generating procedures that every one will follow. Intuition personality types tend to be risk takers and impulsive. However they also make great leaders so if you get the Intuition personality types to buy in to a procedure they will bring the others along with them. To make the procedures palatable to the Intuition personality types, be sure to add some room for creative expression where possible. Understand their need for variety. Allow some options for them to choose from. In training for a new procedure be sure to include real world examples. Use funny stories if possible to get and hold their attention.

I often see procedures fail because the writer assumes that all people think like they do. And many managers think that “Because I said so” is good enough motivation to get people to follow a procedure. If you want employees to follow procedure when no one is looking, you need to consider the personality types of the employees.

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Workpalce saftey tips number two

See the original article here: Work place Safety Tips

2. Use guards and engineering solutions wherever possible instead of relying on PPE – personal protective equipment. PPE is hard to police and uncomfortable to wear. Find a way to prevent the exposure in the first place. Your workers will be much more productive if they are comfortable.

PPe should be used as a last resort for keeping workers safe on a regular basis. Far too often I see PPE used as the primary mechanism for avoiding hazards.

Most machines and operations can be designed with enough guards and safer material flow paths to eliminate hazards for workers without resorting to PPE. Personally I hate working in safety glasses and gloves all day. I would much prefer to work in an environment where I feel safe to be there with out a lot of PPE involved.

At one converting plant I worked with, we designed and installed Plexiglas shields over the folder gluers to eliminate the need for safety glasses when working around the machine. The guards eliminated the hazard of flying cartons while still allowing the operators to see the adjust the process.

Productivity went up and waste went down as operators felt safer interacting with the machine.

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