Another pork chop story

[oso2you]

So I was having trouble with the speed dial on my 520 being hard to turn and hanging up slightly in several spots. I took out the speed mechanism and saw that the teeth on my pork chop (I always get hungry when I think about it) were goofed up. A lot of uneven wear and bent. I ordered a new porkchop part from SS and replaced the old one. Now the round gear that drives the porkchop teeth (not sure what it is called) will turn only two teeth and then will go no further. This gear seems to be in proper condition. Is this a defective part or am I not seeing something to remedy the problem?

[DLB]

So I was having trouble with the speed dial on my 520 being hard to turn and hanging up slightly in several spots. I took out the speed mechanism and saw that the teeth on my pork chop (I always get hungry when I think about it) were goofed up. A lot of uneven wear and bent. I ordered a new porkchop part from SS and replaced the old one. Now the round gear that drives the porkchop teeth (not sure what it is called) will turn only two teeth and then will go no further. This gear seems to be in proper condition. Is this a defective part or am I not seeing something to remedy the problem?

Worm gear, I think. I would focus first on the hinge portion of the assembly that the pork chops swings on. If you look at it as a hinge, then the hinge pin is a roll pin (aka spring tension pin). I've seen the holes on the speed control standoffs worn way oversize because the roll pin split had a cutting action, a roll pin not being an ideal hinge pin. Because of the oversize holes, the pork chop did not swing true. Similarly, the standoff(s) themselves are sometimes bent causing much the same result. The pork chop should be firmly held in place and should swing true, such that it rides centered or nearly so on the worm gear over its range. For any problem in this area, I recommend the Bill Mayo improvements. (Also works to avoid any problems in this area.)

The most obvious thing, I suppose, is make sure that you Control Sheave is lubricated and slides smoothly on the Idler Shaft.

BIll Mayo Headstock Improvement: Go the the Large Format Drawing... thread at or near the top of Maintenance and Repair and see the first post. (download/file.php?id=34357)

- David

[oso2you]

Thank you DLB. I'll check it out