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The following comes to us from Mr. Pink, one of Salt Lake City's finest welders and alchemists. 
I've compiled some specs comparing general mountain axes, forging, and casting. I've also included some metallurgical and philosophical anecdotes
I compared the Air Tech family, Pamir, BD Raven and Raven Pro. Measuring the tip of the axe averaging dimensions 1/2" from end to the end of each tool, here is what I found.
I'll use the abbreviation AT for tools with the Air Tech head.
AT .125" thick by .475" h at tip
Pamir .150 x .450
Raven .250 x .550
Raven Pro .200 x .410
ATR is 50% thinner than Raven at tip
ATR is 38% thinner than Raven Pro at tip
Pamir is 40% thinner than Raven at tip
Pamir is 25% thinner than Raven Pro at tip
Air Tech Evolution is T rated. Air Tech Racing is B rated
Pamir is B rated
BD Raven and Raven Pro are B rated
As far as the name goes The Raven Pro should be called the Raven light. When I want to think Pro I go to the Chevrolet website and look at the 3500 HD. Thats Pro. Its not going to break. Its going to get the job done. When I'm chiseling out kumiko mortises I use a tool that is light and delicate. I must use this tool thoughtfully. When its time to chop I reach for the Atsu Nomi. Forge welded japanese blue steel to 100+ year old iron the Atsu Nomi is for the professional. From perfectly flattened back to top of bevel these chisels are close to 1/2" thick. From this point the tool tapers at the appropriate angle to zero. The tool is then sharpened. Sharp means that when held up to a light you don't see a line at the edge of the blade. Hardened to 64+ Rockwell C, the tool will cut. The forging process ensures the edge will last. Other than not loaning them to anyone I don't give them much thought. I strike my chisels with japanese gennoh hammers. I have a variety of weights ranging from 2.65 oz to about 20 oz. The weight in these hammers come from iron. The striking surface is high quality white steel (shirogami hagane) forge laminated to the iron core. The combination of steel and iron results in a hammer with a dead blow quality. This assures maximum impact for the given hammer weight imparted to the handle of the chisel. They are a joy to use.
There is certainly aggreement that the evolution pick outperforms other technical picks. It does this because it is thinner. The forging process allows it to be made thinner. Hot forging permits the pick to me multidimensional, thus increasing stength, reducing weight and the amount of time spent doing other grinding and shaping processes. Grain structure in important to the overall strength and performance of the pick."Forging yields a grain structure oriented to the part shape, resulting in optimum strength, ductility and resistance to impact and fatigue"(1) Here is an analogy that everybody will relate to. The Louisville Slugger. Louisville Sluggers are made from Ash. Ash is selected for toughness, durability and resilience. Ash has a temper to it. This is the bounce you get when striking a hard surface. The temper is much like that of an anvil. Ash absorbs force, rebounds energy back to the ball and reduces vibration transmitted to the user. All of this comes from material selection and grain structure. The ash ball bat is a perfect example of grain oriented to part shape for maximum benefit.
Forging is stronger than casting. Forged parts are Material granular inconsistencies are worked and refined in the forging process. A casting has neither grain flow nor directional strength. Compare the forged Air Tech part to the cast Raven part. The Air Tech is thinner, stronger and harder. It is more resistant to impact force. The cast Raven part must be made larger to minimally pass strength standards. Larger means more cross sectional area at the tip. This means lower user performance. Larger cross sectional area means that more ice is displaced with each strike of the pick. In poor or bony situations this increases user risk. In heat treatment "Castings require close control of melting and cooling processes because alloy segregation may occur. This results in non-uniform heat treatment response that can affect straightness of finished parts. Forgings respond more predictably to heat treatment and offer better dimensional stability"(ibid) The cast Raven part is heat treated to 42 Rockwell c versus the ATR at 45 Rockwell c. At higher than 42 c the cast part becomes too brittle to achieve strength standards. The higher hardness of the forged part allow it to be made sharper and retain its sharpness longer than the cast part.
This hardness range is right about the desired level of hardnes for an anvil. An anvil needs to have a combination of harness and bounce. Cast anvils are available but they are not desirable. They come from China as a way of exporting
products to American landfills. The forged anvil is the superior product.
Medium density fiber board (MDF) is a wood product composed of wood fibers and chemical bonding materials. It is used extensively in furniture building. The end product has many characteristics of a cast part. It has very uniform grain structure but lacks directional strength, ductility and resilience. MDF makes a poor striking or wear surface. MDF is not resistant to moisture. You wouldn't want to make a baseball bat out of MDF board.
Like chisels, ice axes are cutting tools. Unlike chisels, personal safety can depend on the ice tools you choose.
The forged tool will perform better, be more dependable and longer lasting than the cast equivalent. Good performance means better safety.
Comparing forged parts to weldments and fabrications. "Welded fabrications are costly in high volume runs. Welded fabrications have high labor and inspection costs. Welded structures are not usually free of porosity. Any benefit gained from welding or fastening standard rolled products can be lost by poor welding or joining practice. The grain orientation achieved in forging makes stronger parts. A multiple component assembly cannot match the cost savings gained from a properly designed, one- piece forging. Such part consolidations can result in considerable cost savings.Selective heating and non-uniform cooling that occur in welding can yield such undesirable metallurgical properties as inconsistent grain structure. In use, a welded seam may act as a metallurgical notch that can lead to part failure. Forgings have no internal voids that cause unexpected failure under stress or impact. Weldments require costly inspection procedures especially for highlt stressed components. Forgings do not."(ibid) Weldments must undergo an additional stress relieving heat treatment process. Forgings do not.
Comparing forging to machined steel bar and plate. Steel sizes and shapes available are finite. At least finite until a mill produces a new shape. Products made from steel bar and plate are limited to the dimensions in which these materials are supplied. There is an art to assembling objects with standard shapes. Engineering and assembling a structure or object with one size mild steel angle is an example. At a previous job (with you know who) an engineer there (lets call him George) had experience fabricating mine and drilling equipment. I watched him build many usable devices made entirely from one size angle iron. Measure eleven times if you have to he'd say. George once asked me for all of the 1.5" angle that I had. He was ready to build. A day or so later he had created two one of a kind devices Rube Goldberg would have been proud of. One, a small mixing machine and the other a larger belt driven contraption used to agitate a liquid material prior to tranfer from one tank to another. One size steel angle material, worn out swamp cooler motors and pulleys from a basement of forgotten parts and possibly a dowel rod or long bolt for an axle. They were inspired creations. They were advanced to the point where any further would have been homogeneity. Everyone would have needed to have these devices. They could be mass produced quickly and profitably. The SoCal stucco subdivision sprawl. The green strip of grass in front of your home, Walmart.
The most evolved example of the weldment ice axe could be the Chouinard Piolet. Fiberglass handle, stamped parts welded together, tumbled, then bead blasted, then again tumbled. It was the last few steps that really made it look cool. But thats just it. It just looked cool. Personal opinion aside (because it was the one that started it for me) If I really used it and I mean used it I may have found its weaknesses. I would have cracked the fiberglass handle. I would have beaten it severely enough that a crack would form in the weldment. This in turn would permit water inside the material. In time corrosion would develop. Maybe then I would have broken it. I would have been on the hot forged program years ago.
I'll say with certainty that the forged tool ecclipsed the technology of the future weldment fabricated tool 300 years prior to the invention of the electric arc welder.
In terms of manufacturing having everything under one roof is a good thing. Internal quality control procedures are
adhered to. You know this because you're there. Tooling can be developed and maintained on the spot. System deficiencies are turned to efficiencies on the spot because you control it. Business challenges are more easily remedied in one factory. There are no variable currency values, tarriffs, import shipping costs, telephone charges, transcontinental air fares, or language difficulties. A Just in Time model for the delivery of raw materials can be expected. Delivery of finished goods can be on time because its your factory and you control it. Mike Makely (aka Mr. Pink)
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