Product DescriptionBrass oil cups available in 2-56 and 5-40 thread. The 2/56 size is 3/8" long and the 5-40 size is 15/32" long.
"Well oiled machine" is a phrase that steam engine owners need to live by. Although I have not placed the order yet, four of the 2-56 threaded oil cups will be added to my PMR live steam twin cylinder #7 engine. I have already tapped the holes on top of the main drive shaft and all is ready for installation.
Let me start by saying, I'm no machinist........Drilling the head caps of the #3 Mill engine using the 2-56 Oil Cup requires precision (ooops). I did these on the drill press and using a center punch (hand held / still need to get a vise).......needless to say, I drilled them off center screwing up the small risers. No fault of PM.....aging eyes. Recommended Fix: I used both a round & square needle file notching out the space. This recessed the Oil Cups in a "U" shaped cut retaining the original profile of the caps. I'm actually happy with how it finished up. the recess also allows for a lower mounting and reduced chance of shearing them off now?????