The biggest downside of the Harmonic Drive is that the hole through the center isn't that large. It's currently mounted in four 3D printed pieces to represent what the final mount will look like.

John Do you think it might be possible to place a draw bar and some sort of turned center with a larger diameter than the faceplates hole. Then use standoff to mount your work and run on in reverse.

Webb, It's good to see another successful Heavy 10 project - thanks for sharing the photos. Happy to help you with the drawing. I'm in the process of putting mine back together. I found it at an

Or you could use a locking setscrew. Of course the chuck would always have to stop at the same spot.

So far I haven't had to run my SB Heavy 10L in reverse so I've not run into the problem. But having said that I have this nice Harmonic Drive that will become the A axis on my CNC mill conversion.

I was looking at those pictures of the hook thinking, maybe no one will explain this... the hook mystery will haunt me forever. Now I can finally move on. Also, the chuck spun off my SB 9A last week

Interesting. My L1 does not require a hook. The nut is wide enough to push the chuck off without it. Al

Hi There, That all depends on the breath of experience one has in their lifetime. I had one come loose when I was a first year apprentice. I caught it before it could come off and cause damage but

Ah. So if you just loosened the nut you're still left with the chuck stuck onto the taper. If the hook is flipped up behind the nut then the nut can't move towards the headstock so it pushes the

The hook fills the space behind the take-up nut, so that it can be used to push the chuck off when loosening. allan -- "well, I stand up next to a mountain- and I chop it down with the edge of my

But what is the hook for? John

I've been machining since 1973, with some gaps. Like 35 years, gap. But I'm pretty sure ONE TIME having a chuck spin off would be quite enough. ;) I'm sort of planning, i.e., lightly thinking about,

I never had a chuck come loose if they are seated properly. You are just wasting your energy. Its your lathe and if you like to install a more sure to you Chuck fastening system go for it. You will

Hi There, Despite anecdotal tales to the contrary, threaded chucks do come loose. This is especially true if one has an instant reversing motor. To reiterate, for the third time, all my other

Interesting project. Wonder how you came up with the idea to convert to a L00 spindle. Al

Why would one waist all the this time to convert. I bean in machining over 50 years never had a chuck come of in reverse. Yes i machined in reverse many times never had a problem. The chuck was

Thanks for the link Steve. I've seen those drawings before. But I don't understand why the photos show that hook that pivots. If the L00 just has a nut that is turned onto the threaded part of the

Hi Dave, Here is the progress so far: Thanks Again for the help! Good Luck! -Blue Chips- Webb

Hi There, There have been several types of spindles developed to mount tooling (chucks and faceplates) onto them. The earliest was the threaded type. This type is straight forward but has the

Suggest you google ‘L00 lathe spindle nose’ and you will find chart with dimensions and a cross section. The chuck fits onto a male taper, is driven by a key, and there is a locking ring that gets