Crimping device for refitting broken shovel heads
Torema Products, Davis, CA, USA
ID: FTC1
Relevant Skills: mechanical design, manufacturing, sustainability
The Problem
Most shovel manufacturing formerly done in the U.S. has been sent overseas mainly to China. The majority of the imports have wooden handles but a smaller portion are imported with fiberglass handles. Thailand, the Philippines, and other Asia countries are stripping out hard wood forest for the American markets and shovel handles are included in the mix of products. The trend now is the use of poor quality wood to provide competitive pricing. This results is broken, short-lived shovels that end up in the landfill.
Wood handled shovels have another innate defect. The tapered handles fit into the socket and are secured by a drilled hole traversing the handle where moisture is trapped in both the larger socket and the rivet hole leading to wood rot and premature breakage. The postmortems show that with the leveraging action of the shovel the breaks occur at the rivet hole as its weakest structural point. The question becomes what inexpensive, locally-available product will allow the refitting of a more durable handle adding to years of service, avoiding the cost of foreign imports, eliminating the use hard woods and the foundry pollution of steel smelting more shovel heads?
The Local Solution
There are four little known sources of shovel handles.
Source #1) As cable and dish T.V. has come to dominate the market , high quality galvanized pipe T.V. antennas are being removed and sent to the Asian scrap metal market. Basically the U.S. enters the inferior position in a colonial relationship with primarily China. We send them scrap metal in the form of T.V. antennas. They melt them down in polluting smelters (along with broken shovel heads from the same origin) and then they extrude pipe the same diameter of shovel handles and stamp out steel plate sheets to make shovel heads. Both these products end up exported to the U.S. To circumvent this wasteful paradigm we use the discarded items locally with only slight modifications before assembling into usable products.
Source #2) We import nearly all our electrical conduit used in wiring for commercial and residential applications. When buildings are demolished we strip out the electrical (EMT) conduit and add it to the Asian scrap metals markets. The one inch diameter EMT stock can be fitted to shovel heads. The smaller diameter EMT fits up to rake and hoe heads of which there is a large stock.
Source #3) China sends us many metal shade structures for camping, car ports, and green houses, etc. When the shade covers deteriorate owners ofter find there are no after-market replacement covers and the steel structures still in excellent condition are ending up in landfills. Most of the steel piping is the correct size for shovel handles and the smaller stock is the appropriate size for refitting to garden rakes and hoes.
Source #4) Many steel store display racks are discarded when the items they are displaying are discontinued or the racks show signs of wear or aging. The round stock of display racks (often unused and still in their original shipping boxes) are often the correct size for refitting to garden tool heads of various types including shovels.
Is there a supply of recycled tool heads?: Yes. Farms and garden projects have an abundant and growing supply of heads that would grow even larger if people saw that they are a valuable, recyclable item and not to be thrown in the trash. The scrap yards could be paid the labor cost of setting them aside and derive more profit supplying local tool makers than the low value from current scrap markets.
Back to the Problem and the challenge to the Mechanical Engineers
The round stock highlighted above for shovel handle application requires that the pipe handles be reduced in size on one end to fit into the narrowing socket of the shovel in preparation for securing the head with a rivet. Only 6-7 inches in length at one end needs this reduction. This is the biggest impediment in re-manufacturing broken shovels and must be overcome to increasing competitiveness with the imported sources.
The Device Needed
A crimping device that will indent the last 6-7" of the pipe down the center and then roll the sides to further reduce the diameter is needed. Two types of crimping devices would be most helpful. One hydraulic for commercial manufacturing applications and the other a leverage tool on the model of a construction site rebar cutter for home use and smaller scale tool repair workshops.
The Torema Concept (Totally Recycled Materials) should be kept in mind in the making of these devices. A survey of recycled materials would be an initial step to build components with commonly discarded materials that would allow duplication of the devices in other cities when interested parties are provided with clear instructions and blueprints. Durability and ease of repair are not precluded by the use of recycled materials and, often, the opposite is true.
Will re-manufactured tools supply the entire U.S. market? No, because the feed stock derives from post-consumer recycled content but this model is very advantageous for the already stated reasons to not be consider at a time of growing concerns of climate change. In essence, in economic terms, it is the "harvesting of the low hanging fruit." It can also stimulate questions regarding current U.S. manufacturing models of questionable efficacy.
The possibility of device commercialization: If employment promotion organizations find tool repair a possibility in their mission goals there exist the possibility of online ordering of either of the two devices. The other options is the sale of diagrams and instructions for the DIYers.
Current Market Downturn in the Recyclables Market: As China's economy has slowed prices in more traditional recyclables have plummeted. Cardboard, paper, plastic, tin cans have lower demand. The metals market with scrap steel, aluminum, copper, brass, etc. has followed. With a needed thorough review of our industrial practices it would seem advantageous to be insulated from foreign market swings and bring to the table all the advantages of taking back segments of our manufacturing capabilities we too often declare uneconomic to pursue.
The Problem in the Big Concept
We are downcycling locally available feed stock we already possess, abrogating our evolving philosophy to be less polluting, contributing to the trade imbalance, outsourcing jobs, unnecessarily using limited funds for job retraining programs, and contributing to local unemployment.