One bit of the design of the Lee Pro1000 press that is both clever and a little cheap is the use of a length of ball chain to return the powder measure at the bottom of each stroke. The ball chain works very well in this role., but it is not particularly durable. Mine has broken enough times that it is now too short to use.
Some time ago, I predicted that the chain would eventually be too short and purchased some hardware to replace it with a length of 1/16" steel cable. Due to one of my other hobbies, I generally have a supply such cable laying around.
Last night, the chain broke and, as expected, it was too short to use again. Unexpectedly, however, I could not locate my stash of cable. I was able to work around it to good effect, though it was by using the ball chain again.
The Lee design uses a compression spring to give the return mechanism a positive return, yet some mechanical compliance. Personally, I think this spring is too strong and leads to the failure of the chain. I have contemplated replacing it with a lighter spring, but I think the use of an extension spring instead might prove better still.
My workaround was to mix the leftover ball chain with a new extension spring. The length of the assembly just extends the spring, but it appeared to always retract the powder measure as needed.
It still works basically the same way, but the new spring should put substantially less load on the chain. The spring is rated at just under one pound working load.
No comments:
Post a Comment