Not that it was really necessary, but I decided to work up a more legible feed dial for my lathe, and I thought I’d try making one that works without the knurled thumb screw that locks it in place. With the thumb screw, as you back the cross feed out it interferes with the compound.
Existing stock configuration:
So into the parts stash to see if I have anything useful to start with. I happened to have a 2-1/2” diameter graduated dial - bigger than what I was thinking, but should work. I have no idea what it’s from, but it also has a knurled ring on it, which will come in useful.
First issue is to lengthen the threaded rod to eliminate clearance issues. When doing that I think I should add a bushing to support the extended rod. Then, I needed to come up with some sort of friction resistance so that the dial will turn with the threaded rod / hand crank, but can be turned by hand to reset the zero. I also wanted the whole thing to be reversible to the stock configuration in case I didn’t like the end result.
After a few iterations, I came up with this. Note that instead of locking the larger flange to the main standoff piece I wound up press fitting them together:
To make the new, longer standoff that supports the threaded rod, I pressed two pieces together (.002” undersized) to attach the larger diameter flange to the main stand-off piece. Then I pressed in some oil lite bushings to support the threaded rod and the extension.
The extension itself is pretty standard fare. To lock it onto the existing shaft, I made up a dog nosed set screw that engages the key slot on the existing threaded rod in order to avoid messing up the threads. I also milled a key slot into the extension’s threads so that I can use the stock crank wheel. The 3/4” O.D. On the extension doubles as the new bushing support surface.
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Now for the friction drag on the graduated dial that will hold it in place as you turn the crank wheel, but allows you to rotate the dial by hand to reset to zero. A steel disc just fits the dial’s I.D. and is fit with an O-ring to provide the drag. The disc is locked to the threaded rod extension with a key (a short piece of round rod in this case). To make sure everything doesn’t lock up tight when the nuts and crank dial are tightened, I used a thrust bearing I happened to have, ensuring that the disc inside the dial will rotate smoothly against the face of the main standoff.
Here is the stock standoff and dial
Here is the new configuration
I was pretty surprised with how well it works (for now). We’ll see how it works out over time.
Existing stock configuration:
So into the parts stash to see if I have anything useful to start with. I happened to have a 2-1/2” diameter graduated dial - bigger than what I was thinking, but should work. I have no idea what it’s from, but it also has a knurled ring on it, which will come in useful.
First issue is to lengthen the threaded rod to eliminate clearance issues. When doing that I think I should add a bushing to support the extended rod. Then, I needed to come up with some sort of friction resistance so that the dial will turn with the threaded rod / hand crank, but can be turned by hand to reset the zero. I also wanted the whole thing to be reversible to the stock configuration in case I didn’t like the end result.
After a few iterations, I came up with this. Note that instead of locking the larger flange to the main standoff piece I wound up press fitting them together:
To make the new, longer standoff that supports the threaded rod, I pressed two pieces together (.002” undersized) to attach the larger diameter flange to the main stand-off piece. Then I pressed in some oil lite bushings to support the threaded rod and the extension.
The extension itself is pretty standard fare. To lock it onto the existing shaft, I made up a dog nosed set screw that engages the key slot on the existing threaded rod in order to avoid messing up the threads. I also milled a key slot into the extension’s threads so that I can use the stock crank wheel. The 3/4” O.D. On the extension doubles as the new bushing support surface.
]
Now for the friction drag on the graduated dial that will hold it in place as you turn the crank wheel, but allows you to rotate the dial by hand to reset to zero. A steel disc just fits the dial’s I.D. and is fit with an O-ring to provide the drag. The disc is locked to the threaded rod extension with a key (a short piece of round rod in this case). To make sure everything doesn’t lock up tight when the nuts and crank dial are tightened, I used a thrust bearing I happened to have, ensuring that the disc inside the dial will rotate smoothly against the face of the main standoff.
Here is the stock standoff and dial
Here is the new configuration
I was pretty surprised with how well it works (for now). We’ll see how it works out over time.
