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| Messages 1 - 17 of total 17 in this topic |
Farley
Mountain climber
Portland, Oregon
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Topic Author's Original Post - Feb 6, 2016 - 02:58pm PT
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For those interested in such things, here is a photo of an ORIGINAL blueprint, dated March 14, 1965, for a Long Thick Lost Arrow (early production model, drop forged). Blueprint drawn by Tom Frost and manufactured by Chouinard Mfg. Co. of Burbank, CA, the address being YC's parent's house. An American classic!! Courtesy of TF.
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Fritz
Trad climber
Choss Creek, ID
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Farley: Thanks. I'm always interested in history. Is there a series of blueprints for other Chouinard pitons in your archieve?
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Farley
Mountain climber
Portland, Oregon
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Topic Author's Reply - Feb 6, 2016 - 03:48pm PT
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Yes, a variety of blueprints (most actually bluelines, but all original)drafted masterfully by Tom Frost from 1965 to 1975.
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Fritz
Trad climber
Choss Creek, ID
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Fritz shuffles his feet, looks off into the far distance, and after a pause, shyly asks:
Farley: If it's not too much trouble, could you post more?
Thanks
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WBraun
climber
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You can see Tom Frost's excellent workmanship put into these drawings and their end result as a workable good tool.
The Lost Arrows were such nice pitons compared to what everyone else was making at the time and still to this day ....
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Mark Force
Trad climber
Ashland, Oregon
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Love that stuff. Please share more!
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Evel
Trad climber
Nedsterdam CO
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More Please!
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mastadon
Trad climber
crack addict
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You can tell that vintage by the narrow neck at the eye. Later versions had a wider reinforced area above the eye to withstand side to side hammering during removal. I found a short version of that early model below the North American Wall. Pretty cool stuff.
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SteveW
Trad climber
The state of confusion
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Neat!
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Scrubber
climber
Straight outta Squampton
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That is awesome. I would love to see more too. I love that unusual sort of climbing ephemera. If you have too many, I'd be happy to protect and store it for you in a frame on my wall.
K
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Sula
Trad climber
Pennsylvania
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So what's the next step? How did GPIW go about forging steel into a piton that closely matched this?
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SGropp
Mountain climber
Eastsound, Wa
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If I was going to make a bunch of lost arrow style pitons in various lengths and thicknesses , I would have a set of drop forging dies made to form that one exact shape.
The pitons would be forged to the fully developed form in one or two hits between matching top and bottom dies on a large drop hammer . The two halves of the die would forge the shoulder, the striking anvil, punch and chamfer the eye , stamp the logo and form the body of the blade, all in one operation.
The hammer would be fed a precisely sized white hot billet of allloy steel and the rough forging passed to a trimming die to in a second hammer to remove any excess ''flash'' material.
This basic long thick arrow form could then be forged out to a variety of longer or wider or narrower blade profiles in a second forging operation on a open die hammer by a skilled operator very quickly. Short blade pitons would have the ends cut and profiled in a nipper press. If this was set up right , this whole process could be done in a single heat.
The pitons could be left as forged or heat treated by quenching at the end of the forging heat or in a separate heat treatment in a batch furnace as required.
They would then be cycled through a tumbler to clean up any burrs , and then oiled and packed for shipping.
This would be an economical way to produce a lot of high quality pitons in various sizes without having to have a separate very expensive set of dies made for each size of piton.
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Sula
Trad climber
Pennsylvania
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Thanks SGropp - very interesting.
How do you make drop-forging dies? Is that a job for a milling machine?
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kenny morrell
Trad climber
danville,ca
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very cool, thanks for sharing. I would love to see the other prints that you have.
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Farley
Mountain climber
Portland, Oregon
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Topic Author's Reply - Feb 7, 2016 - 08:39am PT
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Glad folks are interested in these, a testament to the brilliance of Frost (a Stanford-trained engineer) and Chouinard. More images to come including the first stoppers and hexes produced by Choinard Mfg. Co., early piolets, Crack'n'ups, Warthogs, etc.
As a start, here are pics of a bluelines for a very early (first?) production thin Bugaboo from 1965, and early production angles.
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SGropp
Mountain climber
Eastsound, Wa
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The impressions in the dies are cut with various tools such as milling machines , EDM machines , grinders , chisels and files by a specialized tool and die maker. The two halves of the dies form a cavity in the shape of the finished part. They are then fitted into a large drop hammer with precise guides so that when the top and bottom dies are brought together there is perfect registration.
The upper die is keyed into the heavy ram of the hammer which is raised and then dropped or driven down at great force by a steam or air driven piston.
It's important to realize that at no time in the drop forging process is the metal in a liquid state, but in a hot soft solid condition and the whole process is one of plastic deformation and rearrangement of a given volume of material by force and pressure. This gives the strongest part with the least volume of material.
There's a great youtube video called ''Barry Can't 'arf Weld'' that shows the whole drop forging process, although on a much larger scale, but the general process is the same.
https://www.youtube.com/watch?v=sEoZqj53QyM
Drop forging one basic shape of piton would give consistent results to the most difficult to forge aspects; the anvil, eye and shoulder. These could then be easily reforged on much smaller and less expensive open die power hammers to whatever sizes the market demanded.
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| Messages 1 - 17 of total 17 in this topic |
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