Monday, October 31, 2016

The "Other" Legend of Sleepy Hollow

Since it's Halloween, I thought I'd change things up a bit and tell a story that many people may not know.

We all know the famous telling of the tale of a Headless Horseman that terrorizes the Dutch settlement of Tarry Town, NY in a small hidden glen called Sleepy Hollow.

The Headless Horseman, is believed to be the ghost of a Hessian trooper that had his head shot off by a cannonball during a battle of the American Revolutionary War. Story has it that he "rides forth to the scene of battle in nightly quest of his head". 

Please enjoy the story below and read on to find out the "Other" Legend of Sleepy Hollow.

The Legend of Sleepy Hollow tells the tale of Ichabod Crane, a skinny, superstitious, scaredy-cat of a man who is a schoolmaster from Connecticut.  He is in love with Katrina Van Tassel, the daughter of a local wealthy farmer.  Unfortunately he is not the only one who wants Katrina's hand in marriage.  A local "hero" as some called him named Abraham "Brom Bones" Van Brunt also had his eyes on Katrina.  For whomever was to marry her, was also set to one day inherit the farmer's wealth.   

One night, Ichabod decided to attend a harvest party at the Van Tassels' home. He eats, he drinks, plays games and listens to ghost stories just like the rest of the guests, but really only has one thing on his mind and that is to propose to Katrina at the end of the night.  For one reason or another, his efforts failed and was left to go home from the feast alone and defeated.

As he traveled his sad and lonely route through the woods between Van Tassel's farm and the Sleepy Hollow settlement, he passed many of the so called haunted spots the town folk had spoken about in there stories. Spot after spot, he grows more and more frightened of the sights and sounds and just after riding under a devilishly shaped lightning charred tree supposedly haunted by the spirit of a British Spy,  Ichabod is met by a tall, dark cloaked figure on a horse.  Horribly shaken by the size and eeriness of this sight, he is more frightened to see that this ghostly figure did not have a head on his shoulders, but it sat just under his ghostly arm along side his saddle. 

In a frightful race to the bridge next to the Old Dutch Burying Ground, where the Headless Horseman is said to "vanish, according to rule, in a flash of fire and brimstone" after crossing it, Ichabod rides like the wind, pushing his sluggish plow horse down the Hollow and over the bridge. As Ichabod looks back, he is met with the horror of the ghostly figure crossing over the bridge.  The horseman stops, rears his horse, and throws his severed head into Ichabod's frightened face.

As the towns people awakened the next morning, Ichabod was no where to be found as if he just completely vanished from existence. The only evidence that he was ever there was his horse found wandering, a tattered hat, a broken saddle and the puzzling remains of a shattered pumpkin.

With never hearing from Ichabod again, Katrina took the hand of Brom and was married shortly thereafter.   Many say that Brom was behind the whole thing and that he himself was the Headless Horseman as he always has a look of uneasiness as the story of Ichabod is being told.

Many people have different opinions of the story and interpret it in their own way, but usually come to the same conclusion that the ghostly Headless Horseman was really Brom in disguise. Still no one knows where Ichabod Crane has gone and as the story goes on generation after generation the old Dutch story tellers continue to believe and preach that Ichabod was "spirited away by supernatural means," and this leaves us with the legend about his disappearance and sightings of his lost and lonely spirit.

You may think that this is the only ghostly story to come out of Sleepy Hollow, but in fact you are wrong.  There is but another one and I am here to tell you, The "Other" Legend of Sleepy Hollow.  It only seems fitting that is a story about a "bronze" statue.  Who knew bronze could be so scary?!

The Bronze Lady

Halloween night 1916, on the heels of a dare a little girl wanders into the Sleepy Hollow Cemetery. She walks slowly and cautiously around and in between the mausoleums and headstones and then out of no where, she is stopped in her tracks by a sorrowful sound.  As she listens more closely, it is the sound of a woman crying.   

Pushing her fears aside, she follows the sound and is led to a larger than life statue of a seated woman.  The crying has stopped, but she notices something strange about the woman's face.  She climbs up in to the lap of the statue, caresses its face and finds tears falling from the eyes. 

Over the years, some just hear the crying, others just see the tears as the statue sits across from the tomb of the Civil War general Samuel M. Thomas.  Some believe she cries because of a tragedy in her life.  Perhaps, the death of General Thomas. The statue was in fact ordered by his widow shortly after his death in 1903.  The artist was Andrew O'Conner Jr. and he named it Grief.  It is said that she didn't really like the statue at first because she didn't think the woman was gay enough. 

I cannot find any stories or articles about any strange occurrences documented about this statue prior to 1916.  Is it possible that Mrs. Thomas passed in 1916 and maybe it is her spirit in the lady crying over her deceased husband? 

Some say the "tears" can be explained with a scientific theory that its just the statue interacting with the weather and the environment, but the question that always remains is, where is the crying coming from? and that is one question that has yet to be answered.

Tell me...are you brave enough to go visit this statue?

I hope you enjoyed my story telling Halloween edition of our Metalchic Blog.  I hope you have safe, fun filled, Happy Halloween!

Monday, October 24, 2016

Bearing Design Guide: Chapter Sixteen: Effect of the Casting Method on Bronze Alloys

          The casting method should not be ignored but given consideration of the type of service the bronze alloy will be subjected to.

           In particular, the type of load - whether steady and continuous, intermittent or with shock impact or pounding loads - the surface speeds to be encountered and other important features required to be met.

          The casting method has a definite impact on the bronze alloy such as the resulting grain size, density, hardness, mechanical and physical properties, soundness and structure.

          In general, the slower chilled or cooled casting will give rise to coarser and larger grain size. These have a profound effect on the surface qualities, coefficient of friction, wear rate or wear resistance and loads.

          The faster cooled or chilled castings result in greater density, hardness, finer grain size, improved soundness and structure.

           Referring to the illustrations on the following page, please note the finer grain sizes developed by each method of casting.

          Sand Casting: Since molten bronze is poured into a sand mold, the sand or silica having thermal insulating characteristics, will cause slow cooling or chilling of the casting in air. This slow cooling permits the grain size to grow larger, the density, the soundness and structure to be less than by other casting methods.

          Permanent Molded or Chill Casting: The thermal insulating sand is replaced by nickel steel or cast-iron dies. The metal mold quickly chills the casting and this faster solidification results in finer grain size, no interconnected porosity, finer surface finish and improved physical and mechanical properties.

          Centrifugal Casting: Molten metal is poured into a rotating steel or cast-iron die. The centrifugal force impacts the molten metal against the inside of the die, eliminating any porosity. the rotating or spinning die is then sprayed with water coolant to obtain a faster chill than the first two methods discussed the finer grain size further improves the physical and mechanical properties still further.

         Continuous Casting: The molten metal flows by gravity through a graphite die which is chilled
immediately by the cooling jacket surrounding the die. This faster cooling further reduces the grain size and results in still higher physical and mechanical strength.

          The average increase progressively in the tensile and yield strengths is about 5000 to 10,000 PSI and hardness is increased by 10 to 20 points of Brinell hardness.

          Remarks: To further enhances the physical and mechanical properties of the bronzes, extrusion and forging operations can reduce the grain size additionally. These are special processes and the four methods of casting described earlier in this chapter cannot achieve comparable mechanical and physical strength.

Casting Effect On Grain Size and Density

 you can see above, things may look the same on the outside, but they can be very different on the inside.  It is always important to really understand the final application your part will be used in so you know which casting method would be best for you.

          Well...that's it for today. I say goodbye for now. Until next time my metal loving friends...

Tuesday, October 18, 2016

Bearing Design Guide: Chapter Fifteen: Comparative Casting Methods

      When I first starting working here and learning the industry, whenever I would think about molds and castings I would automatically picture Play-Doh in my head.  I mean its a little messy, but seriously, who doesn't like playing with it?  I'm a grown woman and still can't keep my hands off it when my kids have it out.  You can basically manipulate that stuff into whatever shape or form you want and how cool is that?!   Here at Atlas, it just puts that end result on a bigger scale and there are so many more methods of casting your material to get to the desired finished product.

         I love learning about new things and teaching others too whenever I can.  About four years ago I had the opportunity to go to a local elementary school and help the 2nd grade class learn about mass, matter, solids and liquids and just how material can go from solids, to liquids, and right back to solids again.  So instead of Play-Doh...I had a better idea.

          When I was explaining to them that a customer can come to us and ask us to make something for them in the exact shape and size that they want, I decided to show them what I meant.  In order to give the kids a visualization, I decided to bring in some candy melts and candy molds.  As the candy melted in the pot the kids were amazed just how quickly the candy melted.  Once it was ready I showed them the candy mold and started to fill them with the melted chocolate just as if we were pouring molten metal into a mold.  And, just like that with in seconds it began to harden and take a solid form again in the exact shape of the candy mold.

          Needless to say they were pretty amazed and of course a little more excited about the candy treat they were about to have.

          There are various casting methods available for casting ferrous and non-ferrous metals. A brief
description of each follows with a listing of advantages and disadvantages as well as other pertinent data.

Sand Casting: Moist bonded sand or resin coated sand is packed around a wood or metal pattern of the item or items to be cast. The pattern is removed and the cavity or cavities are filled with the molten bronze.

          Following the air cooling of the mold, the casting or castings are removed to be cut or sheared off from the gate and runner as individual castings. Watch the video below.


          Advantages: Any metal can be cast -ferrous or non-ferrous- without limitations to size, weight or shape. It is one of the most versatile and low-cost methods available including tooling costs. This method is economical and suitable for low to unlimited quantities.

          Disadvantages: Close tolerances are difficult to achieve and some machining may always be necessary. Interconnected porosity is generally inherent to this process and a fairly rough surface finish averaging 1000 RMS is obtained. The typical tolerances range from plus-or-minus 1/32 to as much as plus-or-minus .090 and greater across parting lines.

     Permanent Mold Casting: The mold cavities are machined out of a nickel steel or cast-iron die blocks since they are designed for repetitive use. Generally, steel cores are used although sand cores of intricate design can be used. Because of the casting heat, the sand cores are expended while the steel cores can be expected to give reasonable life before they are replaced. The mold halves are clamped together and the molten bronze poured into the cavity by gravity without turbulence or under a low-vacuum pressure.

          The mold is opened within a few seconds following approximately a 50-degree drop from casting, temperature with aluminum bronze or manganese bronze alloys. The casting with gate and riser is ejected immediately.

          Advantages: Good dimensional accuracy is obtained, good grain size and structure results from the rapid chill. Casting tolerances possible range from plus-or-minus .010 to plus-or-minus .015 per side or surface and parting lines can beheld to about plus-or-minus .030.

Casting variations from casting are rarely existent except after tooling begins to show signs of wear.

          Disadvantages: This method is normally limited to non-ferrous alloys. Size, shape and intricacies also are somewhat limited, although many sections can be cast thinner than sand castings. To justify this method, a moderate volume of 1,000 through 50,000 pieces yearly would be necessary to offset expensive tooling costs. Each individual casting must have a gate and riser which reduces the effectiveness of the yield.

          Centrifugal Casting: In this process of casting, steel or cast-iron dies are used and the molten metal is poured into the rotating or spinning die. After pouring, a water spray is directed onto the rotating die, cooling it more rapidly.


           Advantages: Since the molten metal is forced by centrifugal action of the rotating die, the metal thus centrifuged is free of porosity, more dense with a structure designed to carry heavy loads with impacts. The alloy cast in this method can withstand substantial hydraulic pressures without leaking. This method is suitable for ferrous and non-ferrous alloys.

          Disadvantages: Although a controlled stock allowance is set by the die, a machining operation is generally required to remove the rough surface finish and excess stock.

         Continuous Cast Method: In this process, the die is made out of carbon graphite which is surrounded by a cooling jacket through which water flows to chill and solidify the cast tube, bar or shape. As it exits from the furnace proper by gravity, the casting solidifies. It is pulled out slowly by pull rolls or pinch rolls. This rapid cooling reduces the grain size and as the casting exits from the lower section of the holding furnace, a homogeneous micro-structure is obtained.

           Advantages: A minimum of stock allowance can be controlled to plus-or-minus . 015 reducing the amount of machining necessary as in other methods. Various shapes are cast reasonably to size without need for precision machining. The resulting structure is generally suitable for acceptance by radiographic tests and will withstand a substantial hydraulic pressure without leaking.

           Disadvantages: Initial high unit cost investment and space; graphite dies must be replaced after each run and each size requires a cooling jacket.

Die Casting: Molten metal is forced into closed steel dies at high velocities by application of pressure.


          Advantages: Excellent dimensional accuracy is obtained across parting lines plus-or-minus .005 and plus-or-minus .001 to plus-or-minus .003 across extremities and surface finishes 100 RMS or less.

          Disadvantages: This process requires high volumes of20,000 to a million pieces or more since the relative die cast is extensively high. It also is limited to non-ferrous metals and porosity may be encountered as a result of entrapped air in the die. Size is limited to 3 feet square and under 15.0 pounds.

           Investment Casting: Various ferrous and non-ferrous materials are used to make a wax or thermoplastic pattern which is expendable in the process. Hot wax or plastic is injected to make a pattern under pressure into the die and multiple patterns are mounted on a common sprull made of the same material. The assembly, called a tree, is dipped into a liquid surry followed by several immersions in dry fluidized bed of fine sand. Each dipping operation requires drying time. As many as five to eight clippings are required to build a shell around the tree. For wax removal, the tree is placed into a steam autoclave. Before pouring, the molds are kiln-dried and tongued from the furnace to the pouring box and poured while cherry red.

          Advantages: There is no parting line and no draft. The surface finishes are less than 125 RMS and shapes are cast which couldn't be produced by other methods. This process becomes most economical when two or three machining operations can be eliminated. The typical tolerances are usually plus-or-minus .005 and high volume is not a criterion. Tooling is less costly than pressure-die casting.

          Disadvantages: Although this method has the fewest design limitations of shapes, size or design, pound for pound the cost of this process is comparatively high.

          There are several other methods of casting which include shell molding as a modified sand casting which offers closer tolerances as plus-or-minus .007 to .015. The surface finish is much better than sand casting and there is better definition of details such as lettering, etc. The cost of pattern equipment is higher than for sand casting and the process necessitates higher quantities.

  Plaster molding and ceramic mold casting are similar to investment casting. But the molding material is more expensive and the processes have never been suitably automated to reduce the labor intensity of making the molds. The casting tolerances are reasonably close to investment casting.

          I have to tell you this was the best post I have done so far!  Watching all the videos was so much fun.  I hope you enjoyed learning about the different options of casting and watching how all of the processes are done.

Well...that's it for today.  I say goodbye for now.  Until next time my metal loving friends...

Next Up: Chapter 16:Effect of the Casting Method on Bronze Alloys

Monday, October 3, 2016

Bearing Design Guide: Chapters Thirteen and Fourteen

Bearing Design Guide: Chapters Thirteen and Fourteen

The next two chapters focus on lubrication and lubricants so I have paired them up for this weeks post.

Bearing Design Guide: Chapter Thirteen: Lubrication & Lubricants

          The importance of an oil depends mainly on its film forming ability which depends further on its viscosity.

         An oil of lowest viscosity is generally more suitable for an application since a higher viscosity oil will waste power to overcome the internal friction of the oil itself

          There are many ways to supply a lubricant to a bearing.  We will explore the different options below.


      Pressure lubrication is probably the most positive and efficient means to provide lubricant to a bearing.
In addition to offering a more copious supply of oil lubricant, up to an average pressure of 50 PSI, it coats the bearing, maintaining a more stable viscosity range and it assists in flushing out dirt and wear debris from the bearing surface.


  Oil bath lubrication is where the bearing is submerged in oil which makes it the next reliable method to the pressure-fed oil. The shaft speed should not be so great as to cause excessive churning of the oil.

          Splash-fed lubrication involves the oil being splattered onto the bearing surface by movement of other adjacent parts. The housing should be reasonably oil-tight to prevent excessive loss and leakage of the lubricant.



Oil ring lubrication involves a revolving or processing ring on a shaft in contact with the oil sump. When the shaft is at low speed, sufficient oil may not be brought to the bearing surface or if the shaft speed is too great, the oil will be centrifuged beyond where it is needed. It also may not keep pace with the oil required.

          For best results, it has been proposed that the peripheral speed should be in the range of 200 to 2000 feet per minute. The safe load based on full hydrodynamic lubrication mode should be reduced by one half of pressure lubricated bearings.

          Wick or waste-pack lubrication delivers oil to a bearing surface by capillary action of a wick or waste-pack as done in many old railroad axles using bobbitted bronze backed partial sleeve bearings.


          The safe load when compared with pressure-fed full hydrodynamic load should be reduced to 1/4 of the load.

         Grease-packed bearings: Grease is generally packed to surround the bearing and although is substantially less effective than oil, it is much more permanent but the bearing will generally operate in boundary conditions.

Bearing Design Guide: Chapter Fourteen: Lubricant Selection

           The selection of a lubricant is based on various factors such as the type of operation, whether full hydrodynamic, mixed film or boundary film conditions in addition to the surface speed and bearing load involved.
          Various lubricant articles suggest some recommended viscosities for specific services.
          As a rule of thumb, the following suggested viscosities should be considered on the basis of surface speed with a qualified load.

                                Speed(fpm)                 Viscosity(sus)                   SAE Oil
                                 30 or less                       1200-1800                           80
                                 70                                    800-1200                           70
                                 150                                  500-800                             60
                                 300                                  300-500                             50
                                 600                                  150-300                             40
                                 1200                                120-150                             30
                                 2400                                  90-120                             20
                                 5000                                  40-90                               10
                                 over 5000                            5-40                                 5

          As a general rule of thumb, heavier oils are recommended for high loads and lighter oils for high speeds.
          In order to obtain a quick conversion of viscosity (sus) to centistokes (cSt), multiply the (cSt) value by 5. The multiple will be the approximate (sus) value.

         To obtain the (cSt) value, divide the (sus) value by 5.

         These results are reported to be accurate within 7% in the range of75 to 7000 (sus) and 15 to 1500 (cSt).

          But also be cautioned that this assumption should not be used below 75 (sus) or 15 (cSt).

          For more explicit lubrication data, we suggest you refer to the CBBI manual or to the Machine Design article of March 10, 1966.

I hope this weeks post wasn't too DRY for you and this helped you learn about lubricating methods with ease.  Anyway, that's it for now.  Until next time my metal loving friends...

Next Up: Chapter 15: Comparative Casting Methods