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BABBITING A HAMMER PART II
REPAIRING THE BEARING CAPS
In the first installment, I described how to pour babbit bushings in the main bearings intrinsic to the hammer, front and back. Those bottoms of the bearings, now babbited, need similar babbiting in the tops of the two bearings, in the cap pieces.
Both of the bearing caps that you removed, front and back, should have oil cups for lubrication. When running your hammer later, after you babbit the top halves of the two bearings, you should liberally lubricate your bearings by filling the two cap pieces with oil in the lubrication holes.
Similar to the bottom halves of the bearings, old remnants of old babbit should be removed from the area where the main shaft turns in the caps. Then, just as you did in the bottom halves of the bearing, take a small drill and drill two small ¼ inch holes into the semi-round area where you are about to pour the molten babbit, NO MORE THAN 3/8 Inch deep. These two tiny holes, when you pour molten babbit into the bushing area, will keep the cooled babbit from jostling or moving later. Then, using your trusty DAP window putty, deliberately fill the oil holes and oil cups with window putty, so that when you pour the babbit bushings, the molten babbit will not run out the oil holes and oil cups in the front and back bearing caps that you are repairing right now. Then, similarly to how you poured the bottom halves of the bushings in the bearing halves intrinsic to the hammer, hang these two caps upside down under the shaft from baling wire suspended from a wooden two by four frame, exactly positioned where the shaft turned when the hammer was running previously. The two caps should cradle, hanging upside down, the main shaft, both centered around the main shaft, neither too high or too low, but CENTERED. When you are happy about the positioning, dam up both ends of each cap, between the cap and the shaft, with DAP window putty.
The next step is to pour your bushings. When we did it, we made sure we heated up enough babbit in the ladle to pour the bushings in both caps in the same heat. As stated earlier, we used a coal forge to heat up the babbit in the ladle. When the babbit was molten, we poured it into the gaps in the caps hanging upside down between the shaft and the cap housing, pouring the molten babbit into both upside down caps carefully. As soon as the babbit cooled, we removed the damming material at the ends of both caps and the damming material which we had placed in the oil holes and cups.
As with the bottom halves of these bushings, we took a fine chisel and scored the new babbit with thin grooves to hold oil. Then we reassembled the hammer, reattaching the fly wheel at the end of the shaft, from which the tup is suspended. Then we replaced the bearing caps, newly babbited, and filled the oil cups with thirty weight motor oil. Voila, the hammer, newly babbited, ran as “good as new”. Over thirty years later, this hammer is still running strong, with no slop in the main bearings. I strongly advise folks, after they rebabbit their bearings, to use lubrication in these bearings on a regular basis. This will prolong the efficacy of your hammer. GOOD LUCK!
REPAIRING THE BEARING CAPS
In the first installment, I described how to pour babbit bushings in the main bearings intrinsic to the hammer, front and back. Those bottoms of the bearings, now babbited, need similar babbiting in the tops of the two bearings, in the cap pieces.
Both of the bearing caps that you removed, front and back, should have oil cups for lubrication. When running your hammer later, after you babbit the top halves of the two bearings, you should liberally lubricate your bearings by filling the two cap pieces with oil in the lubrication holes.
Similar to the bottom halves of the bearings, old remnants of old babbit should be removed from the area where the main shaft turns in the caps. Then, just as you did in the bottom halves of the bearing, take a small drill and drill two small ¼ inch holes into the semi-round area where you are about to pour the molten babbit, NO MORE THAN 3/8 Inch deep. These two tiny holes, when you pour molten babbit into the bushing area, will keep the cooled babbit from jostling or moving later. Then, using your trusty DAP window putty, deliberately fill the oil holes and oil cups with window putty, so that when you pour the babbit bushings, the molten babbit will not run out the oil holes and oil cups in the front and back bearing caps that you are repairing right now. Then, similarly to how you poured the bottom halves of the bushings in the bearing halves intrinsic to the hammer, hang these two caps upside down under the shaft from baling wire suspended from a wooden two by four frame, exactly positioned where the shaft turned when the hammer was running previously. The two caps should cradle, hanging upside down, the main shaft, both centered around the main shaft, neither too high or too low, but CENTERED. When you are happy about the positioning, dam up both ends of each cap, between the cap and the shaft, with DAP window putty.
The next step is to pour your bushings. When we did it, we made sure we heated up enough babbit in the ladle to pour the bushings in both caps in the same heat. As stated earlier, we used a coal forge to heat up the babbit in the ladle. When the babbit was molten, we poured it into the gaps in the caps hanging upside down between the shaft and the cap housing, pouring the molten babbit into both upside down caps carefully. As soon as the babbit cooled, we removed the damming material at the ends of both caps and the damming material which we had placed in the oil holes and cups.
As with the bottom halves of these bushings, we took a fine chisel and scored the new babbit with thin grooves to hold oil. Then we reassembled the hammer, reattaching the fly wheel at the end of the shaft, from which the tup is suspended. Then we replaced the bearing caps, newly babbited, and filled the oil cups with thirty weight motor oil. Voila, the hammer, newly babbited, ran as “good as new”. Over thirty years later, this hammer is still running strong, with no slop in the main bearings. I strongly advise folks, after they rebabbit their bearings, to use lubrication in these bearings on a regular basis. This will prolong the efficacy of your hammer. GOOD LUCK!
