A view on alignment of the shopsmith.

[DLB]

If you see this as an issue is there any reason you can not just "invert it" again. Can the allen wrench be inserted upward from the under side?

Yes, the setscrew can thread in either way. Access from the bottom is somewhat limited, a ratchet driven key works well. Ideally someone whose machine does not lock as well will try this and report back, or report that theirs is already this way to rule it out.

Are these differences significant factors?

The only one I have access to is the same as in your pictures, and it locks up fine. I like the bushing though, gives the action a bit of precision and I would expect it to lock as well with less force. For those whose way tube assembly isn't locking well, I feel certain that the screw is moving around in the Headrest hole because it is such a loose fit. The bushing eliminates most of that play between the locking screw and Headrest casting. Clearly this is not the cause of the problem, but earlier in the thread RFGuy asked about differences of previous versions. Functionally, the bushing significantly changes the behavior. But we know the machine should lock either way.

- David

[dusty]

If you see this as an issue is there any reason you can not just "invert it" again. Can the allen wrench be inserted upward from the under side?

Yes, the setscrew can thread in either way. Access from the bottom is somewhat limited, a ratchet driven key works well. Ideally someone whose machine does not lock as well will try this and report back, or report that theirs is already this way to rule it out.

Are these differences significant factors?

The only one I have access to is the same as in your pictures, and it locks up fine. I like the bushing though, gives the action a bit of precision and I would expect it to lock as well with less force. For those whose way tube assembly isn't locking well, I feel certain that the screw is moving around in the Headrest hole because it is such a loose fit. The bushing eliminates most of that play between the locking screw and Headrest casting. Clearly this is not the cause of the problem, but earlier in the thread RFGuy asked about differences of previous versions. Functionally, the bushing significantly changes the behavior. But we know the machine should lock either way.

- David

What is the OD of the bushing? The spring (where it acts as a bushing) measures .5495" and there is virtually no slop between the spring and the screw.

[RFGuy]

Can someone post a pic of what the tie bar clamp looks like with the bushing, etc.? I am just trying to visualize what might be different between these. I know David mentioned possibly the head of the screw being larger on some of them, but other than that it sounds like a bushing is likely the main difference. I don't have excessive play on mine, but there is some play when fully locked. If there are iterations of the Mark V that are more secure for the tie bar I would just like to understand the differences.

[DLB]

F

Can someone post a pic of what the tie bar clamp looks like with the bushing, etc.? I am just trying to visualize what might be different between these. I know David mentioned possibly the head of the screw being larger on some of them, but other than that it sounds like a bushing is likely the main difference. I don't have excessive play on mine, but there is some play when fully locked. If there are iterations of the Mark V that are more secure for the tie bar I would just like to understand the differences.

First image shows the two types we've discussed together. Second image is the Greenie Headrest Lock disassembled. The bushing has a 3/8" I.D. and 5/8" O.D. and is 1-1/2" long, and appears to me that it is made of two sleeves pressed together.

Headrest Lock.JPG (313.42 KiB) Viewed 994 times

Greenie Lock.JPG (237.68 KiB) Viewed 994 times

- David

[RFGuy]

Thanks David. I didn't even know the tie bar clamp had a spring inside it. Mine has never been taken apart. Can you do me a favor and measure the OD of the bushing? I am contemplating adding it to mine. As I said, I think I see about +/- 1/8" of play on the waytubes with it locked. I don't use the aux table on the left side so I didn't see any issues with alignment that I know of. However, sometimes I find it hard to start the connector tubes into the table rails between the main table and the aux table on the right side. I am wondering if this small amount of play of the waytubes is causing this issue sometimes. Might be interesting for me to try it with a bushing to see if it helps.

[DLB]

The OD measures 5/8". The roundness isn't as perfect as one might expect. There is a visible seam, but no gap. As I said it appears to be two pieces pressed together, the seam in the inner is rotated ~180 degrees from the outer. More complex, for whatever reason, than a simple 3/8 X 5/8 X 1-1/2" bushing. But it was the 50's, maybe they made them themselves?

- David