Lathe Chuck Injury Due to Faulty Lathe Operation

One of the more interesting cases that we have been assigned had to do with a personal injury suffered as a result of an airborne chuck.  The injury occurred after an individual purchased a chuck and spindle adapter for use with a Shop Smith lathe that was manufactured back in the late 40s or early 50s (see photos below).

 

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Chuck and pin wrench used to tighten chuck onto spindle adapter

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Antique Shop Smith Lathe

After attaching the spindle and mounting the chuck, the owner started the lathe and tested the operation.  Everything went well until the machine was turned off.  As soon as it was, the spindle shaft stopped but the chuck kept spinning and spun itself off the adapter.  The chuck went airborne, bounced off parts of the lathe and hit the owner’s hand causing severe injury.  The investigation came about as a result of the owner’s allegation of a defective product, ie, the chuck was defectively designed and had no means of stopping if it separated from the spindle adapter.  The chuck is designed to be tightened against the spindle adapter using special wrenches.  According to the owner, he claimed that he “tightened the chuck as tight as he could” before starting the lathe.  During the examination of the lathe, the lathe was started and run without the chuck attached.  When the lathe was turned off, it immediately became clear that there was something wrong when the spindle shaft did NOT coast to a stop.  It was also clear that the abrupt stop provided the torque necessary to cause the chuck to spin off the spindle adapter.  In addition, it was also noted that if the chuck was to stay attached to the spindle adapter, the torque applied during tightening had to be greater than the torque causing separation.  After working the math, it was determined that the owner could not have tightened the chuck was much as he claimed.  As a result, it was further determined that the owner unfortunately caused his own injury by ignoring the problem of abrupt stopping of the spindle shaft.  The lawsuit was subsequently dismissed.

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Power Steering Recall

Roughly two years ago, Chrysler recalled approximately 442 Dodge Ram pick up trucks for a problem with the electric power steering (EPS) module.  The recall applied specifically to 2015 -2016 Ram 1500 trucks manufactured between January 22, 2015 and September 13, 2015.  The problem had to do with short circuiting of the EPS circuit board that would cause the loss of power steering and increase the risk of a crash.  Since that recall was put in effect, reports have been received that indicate that the short circuit is not enough to cause the 100 amp fuse, that is supposed to protect the module, to open.  As a result, the short circuits are causing wiring to overheat and ignite resulting in vehicular fires.  It should be noted that overheating of the wiring has not been addressed and is not part of the original recall.  The original recall is identified as NHTSA campaign # 16V16700 and Chrysler recall # S19.  A copy of the recall is attached below.  The second page shows a wiring diagram and the connection between the EPS module and battery through the 100 amp fuse that is in question.  Also shown is the connection between the battery and the power center.  If a fire occurs, the origin appears to be in the area of the battery and power center, both of which are located on the driver’s side of the engine compartment above the left front wheel well.  Complaints regarding vehicular fires related to this recall should be reported to NHTSA through their website at www.nhtsa.gov.

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Long Hydraulic Hoses Cause Trencher Fire

Heavy equipment used on construction sites are subject to all kinds of conditions.  Those conditions include, bad weather, rocky terrain, and remote locations.  All of these factors can play a part in determining whether a vehicle will ignite and burn.  We were recently asked to examine a trenching machine that was destroyed by fire.  The machine that was examined is shown below.

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One of the most common causes of heavy equipment fires is hydraulic fluid leaks.  It is well known that hydraulic fluid is flammable and will ignite with the correct mixture of air and an ignition source.  Such sources can include engines and transmissions as well as electrical devices.  Although these are some of the more common factors, sometimes unusual circumstances can also lead to a piece of equipment being destroyed.  In the case of the fire damaged trencher, one of the findings included hydraulic hoses being long enough to reach the ground.  As a result, while the trencher was in operation, dirt was actually burying the hoses.  At the same time, the movement of the machine, as the trench was dug, was pulling the hoses through the dirt and causing the hoses to tear.  Hydraulic fluid leakage was not only inevitable but, so was the possibility of fire.  When hydraulic hoses have to be replaced, the lengths of the hoses are a maintenance issue.  It is extremely important that hoses of correct length are installed,  If the hose is short and fits tight between connections, the stress imposed by forcing the hose to stretch coupled with the stress of pressurization, can cause premature failure.  Likewise, a hose that is longer than necessary will move around and possibly make contact with solid objects that can wear or cut the hose jacket, weakening the wall.  As in this case, the dirt and rocks contributed to the weakening of the hoses found beneath the conveyor section, on the ground, and the subsequent release of hydraulic fluid that ultimately ignited and destroyed the trencher.  The hoses that were found are also shown below.

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GM Recalls for Loss of Power Steering

General Motors (GM) has announced that it is recalling 1.2 million pick up trucks and SUVs due to a temporary loss of power steering.  The recall applies to 2015 Chevrolet, GMC and Cadillac vehicles.  When the power steering disappears, the vehicle can become difficult to control increasing the risk of a crash.  GM has received 30 reports of crashes and two injuries.  GM will update the power steering module software free of charge for owners of the recalled vehicles.  For additional information, owners can contact GM by calling 1-866-522-9559.

 

Fire Hazard Prompts Ford to Recall 2 Million F-150s

The National Highway Safety Administration, NHTSA, has announced that Ford has recalled approximately 2 million F-150 pick up trucks.  The recall applies to 2015 -2018 F-150 regular and super crew cab pick up trucks.  The seatbelt pretensioner can generate sparks when activated during a sudden stop.  The sparks can ignite flammable material located inside the “B” pillar post including carpeting and insulation.  Ford has also identified the manufacturers of the seatbelts.  Joyson supplied the seatbelts for the 2015 to 2017 models while ZF supplied the belts for the 2018 year models.  Approximately 1.62 million vehicles were sold in the United States, 340,000 vehicles were sold in Canada and 37,000 were sold in Mexico.  The recall is expected to begin on September 24, 2018 with Ford notifying owners.  The Ford recall identification number for this recall is 18S27.  NHTSA’s campaign number is 18V568000.  For additional information, consumers can contact Ford by calling 1-866-436-7332 or visiting Ford’s website at www.ford.com.

 

 

 

Gas Logs and Soot Damage

This is a subject that I have blogged about in the past.  Gas log sets are very popular with homeowners and tend to create or add to a warm atmosphere when used.  However, soot damage is continuing to occur because manufacturers continue to build log sets that burn natural gas or propane incompletely.  That is, unburned carbon is escaping in the combustion gases and settling on walls, ceilings, furniture, clothing and anything else that happens to present a cool surface.  The science of combustion of gaseous fuels is well known and by no means new technology.  It has long been recognized that a blue flame is indicative of the closest to complete combustion that can be achieved.  The secret is mixing enough air with the fuel to obtain the correct mixture.  When the correct mixture is obtained, a blue flame results.  In contrast, flames with yellow tips or long yellow flames are indicators of incomplete combustion.  These are the flames that produce unburned carbon that ultimately settles on various surfaces as soot.  There is nothing that a homeowner can do to change the burning characteristics of a log set as the appearance is an inherent design.  If the log set is installed in a ventless fireplace, 100% of the products of combustion will enter the living space.  As a result, all of the soot produced will also enter whatever space the set faces.  If the set is installed in a fireplace with a chimney, then it is possible to control the ventilation of the gases by opening the chimney damper and allowing the gases to escape.  Instead of entering the home, soot usually travels up the chimney and settles on the walls and damper instead of the interior.

If you are unlucky enough to have soot damage, I recommend doing the following: first, take plenty of pictures of the places where soot has been deposited.  It is possible that you might be called upon to prove that soot damaged specific belongings.  Second, notify your insurance carrier.  Homeowners policies usually give policyholders a toll-free telephone number to call in the event that a claim has to be filed.  If you can’t find the number, call your insurance agent.  Your agent also has access to the insurance carrier and can report the claim or tell you what to do.  Third, start making a list of the damaged items.  The adjuster that will be assigned to your case will need to have an itemized list of damages so that they can begin to prepare estimates for those things that can be repaired or will have to be replaced.  Fourth, be prepared to have the gas logs set become the center of controversy.  Your carrier will most likely want to have the set examined by an engineer in order to establish a product defect.  The manufacturer also has the right to examine the set.  In doing so, both sides will have questions and will want access to your home and specifically, the area where the set was located.  Both sides will need documentation in the form of the owner’s manual, purchase invoice, and the metal identification plate that comes with the log set and is NOT supposed to be removed.  Fifth, the log set will become evidence and must be preserved as such.  The engineer hired by your carrier will want to take possession of the log set and place it in storage in anticipation of further examination or for use in court, if the need arises.  Sixth, cases can take months if not years to settle.  So, don’t expect to get the log set back anytime soon after it is taken.  Seventh, if you replace the set with another gas log set, remember that the possibility of soot damage returns again.  The only way to minimize the possibility of soot damage is to limit usage times to short periods or stop using the set altogether.

 

Contents of Aerosol Cans can be Flammable!

During a recent vehicle fire investigation, it was discovered that the owner had been carrying at least eight aerosol cans of different products during the hottest month of the year so far.  The fire resulted in the destruction of a Toyota Highlander that was only months old.  This is a perfect example that illustrates the fact that people will forget that the contents are flammable and that the potential for explosion and fire is very real.  In this particular case, some of the contents of these cans were identified as Raid Multi 7 Insect Spray, Bayer Advanced Home Insect Spray and Aqua Net Hair Spray.  The cans that were recovered are shown in the photograph below.  It was also determined that at least one of the cans exploded prior to the fire.  It is imperative to remember that when products in aerosol cans are purchased, they should be stored in a cool and dry place, not left in a hot vehicle.  Not all aerosol cans contain flammable ingredients but, if you are not going to read the label, then treat them as flammable and store them accordingly.

 

 

 

 

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