- Aug 18, 2009
- 154
- 1
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Synopsis:
Miller Manufacturing makes many different lines of poultry equipment under the "Little Giant" brand. A problem exists with the execution of their plastic hanging feeders' design. I present today an analysis of the problem and two different solutions.
The Design:
The specific products under consideration today are the plastic 11- and 22-pound hanging feeders. A 1/4-20-threaded rod passes through the center of the tube and the pan to hold the feeder together, secured on the bottom with a wing nut and on the top by a modified wing nut that includes a hanging loop. The top is trapped between the modified wing nut and a coil spring that permits adjustability of the gap between the pan surface and the bottom of the feed tube, allowing the feed level in the tray to be varied.
The Problem:
I returned home one evening to discover the pan laying in the litter and the contents of the feeder dumped on the floor. The bottommost wing nut and its associated hardware were not found. The assumption is either they were consumed by a chicken then excreted outside or they are still in the litter.
An Analysis:
Upon observing the chickens eating from the other feeder, I noted the chain the feeder hangs from developed some degree of windup as the chickens fed, resulting in it unwinding when no chickens were eating. I assumed that this rotary force was the cause of the feeder's spontaneous disassembly and went to work on forestalling or preventing a recurrence.
I acquired a flat washer with a nominally 1/4" I.D and a 1/4-20 lock nut. I then disassembled the remainder of the feeder, assembled the pan to the central rod with the lock nut, and drew it up tight until the crimped portion of the central rod was level with the top of the flat washer. (A properly sized washer would not have allowed the crimp to pass through its central hole; unfortunately, the washer I got did allow this.) The tube was then reassembled on the central rod and the feeder placed back in service.
Further Problems:
While refilling the feeder one morning I discovered the anti-scratch vanes were above the top of the pan. A moment's examination disclosed the top wing nut had backed off from where I had left it, allowing the spring to raise the tube. Further observation and analysis disclosed the presence of the chain windup already observed and the potential to repeat the previous spontaneous disassembly.
Potential solutions are to use a threadlocking compound to secure the top wing nut in the desired position or install a swivel in the chain to prevent its winding up. Unfortunately, some of these threadlocking compounds will degrade certain plastics and swivels add to the expense of hanging the feeders.
Ultimate Solution:
I allowed that feeder to run empty then replaced it with a Little Giant galvanized tube feeder with a 14" pan. The chain has wound up but the feeder has not come apart yet. Since its assembly forces are applied through the mechanism of sprung metal rather than threaded rods I do not anticipate it coming apart any time soon.
RSD
Miller Manufacturing makes many different lines of poultry equipment under the "Little Giant" brand. A problem exists with the execution of their plastic hanging feeders' design. I present today an analysis of the problem and two different solutions.
The Design:
The specific products under consideration today are the plastic 11- and 22-pound hanging feeders. A 1/4-20-threaded rod passes through the center of the tube and the pan to hold the feeder together, secured on the bottom with a wing nut and on the top by a modified wing nut that includes a hanging loop. The top is trapped between the modified wing nut and a coil spring that permits adjustability of the gap between the pan surface and the bottom of the feed tube, allowing the feed level in the tray to be varied.
The Problem:
I returned home one evening to discover the pan laying in the litter and the contents of the feeder dumped on the floor. The bottommost wing nut and its associated hardware were not found. The assumption is either they were consumed by a chicken then excreted outside or they are still in the litter.
An Analysis:
Upon observing the chickens eating from the other feeder, I noted the chain the feeder hangs from developed some degree of windup as the chickens fed, resulting in it unwinding when no chickens were eating. I assumed that this rotary force was the cause of the feeder's spontaneous disassembly and went to work on forestalling or preventing a recurrence.
I acquired a flat washer with a nominally 1/4" I.D and a 1/4-20 lock nut. I then disassembled the remainder of the feeder, assembled the pan to the central rod with the lock nut, and drew it up tight until the crimped portion of the central rod was level with the top of the flat washer. (A properly sized washer would not have allowed the crimp to pass through its central hole; unfortunately, the washer I got did allow this.) The tube was then reassembled on the central rod and the feeder placed back in service.
Further Problems:
While refilling the feeder one morning I discovered the anti-scratch vanes were above the top of the pan. A moment's examination disclosed the top wing nut had backed off from where I had left it, allowing the spring to raise the tube. Further observation and analysis disclosed the presence of the chain windup already observed and the potential to repeat the previous spontaneous disassembly.
Potential solutions are to use a threadlocking compound to secure the top wing nut in the desired position or install a swivel in the chain to prevent its winding up. Unfortunately, some of these threadlocking compounds will degrade certain plastics and swivels add to the expense of hanging the feeders.
Ultimate Solution:
I allowed that feeder to run empty then replaced it with a Little Giant galvanized tube feeder with a 14" pan. The chain has wound up but the feeder has not come apart yet. Since its assembly forces are applied through the mechanism of sprung metal rather than threaded rods I do not anticipate it coming apart any time soon.
RSD
