Rotary live center pin spacing

Has anyone else found that, at times, when they put their stock into their rotary, the live center does not fit with the stock’s length?

My rotary is aligned with my 60" X-axis. Per the assembly instructions, the linear rails are 1" from the tailstock end of the rotary frame.

When I loaded a 24-1/4" long stock into the chuck, the live center could not extend far enough to engage the tail of the stock.

When I moved the live center closer by one pin hole, the live center could not be retracted back enough to get the stock in place. Nor was it possible to move the live center back a pin hole, insert the stock, then “push” the live center forward into the stock until the closer pin hole clicked into place. There is no leverage to do that because the live center, being unlocked, simply slides back to the farther pin holes and you’re back to condition 1. There seems to be a design gap in the spacing of the linear rail pin holes.

This is solvable, just a bit more work for the user. I had to drill a V divot into the tail stock to allow more room for the live center to be moved into place after I had inserted the stock into the chuck.

Wood was easy to resolve. Aluminum would have been a bigger pain to drill the divot. If anyone else has had this issue come up, hopefully Avid will update their pin spacing design for future purchasers.

Matt

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I’m distracted by the glued up plywood, the incised line and number- what’s it going to be?

Hi Christopher,
It turned into this: Sculptural plywood vases
-Matt

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File this as a ‘hack’ rather than a solution to your problem: Use more than one live center. It will almost certainly have a different length, so the gap will no longer exist. It’s a 2MT taper.
Actually, the whole tailstock is a bit of a disappointment compared to the rest of the overall rotary kit (which I think is great). I’ll likely use my Robust live center (shown below). The handwheel has to go too.

I reported this well over a year ago
I then did the “hack” and just used 2 different live centers.
I was then having problems with inconstant parts. I did find out that with the center extend it just was not stable.
So I bought a 2nd center. Now I never extend the center that is holding the part I am running and use the 2nd center to just push the front center into the part.
I have found That I now get constancy in the parts off of the rotary.

Yikes! That’s scary.
So if I’m understanding this correctly the problem you found was the combination of the live center and extended quill barrel gave you unacceptable deviation. Is that right?
Do both of your tailstocks behave in the same unacceptable way? It makes me wonder if the point of the extended live center is off axis. Or is there flex?

I never noticed that before. I just went and measured mine and the usable stroke of the tail stock is only 2", but the stop spacing is 2.38". That is definitely a design error. The spacing needs to be less than the travel to guarantee it will always reach.

Let me add this question to the mix:
Has anyone tried - and been successful - with re-greasing the rolling bearings underneath the live center plate? I tried with a normal grease gun (essentially identical to the one Avid supplied) but the grease gun’s tip just cannot quite get underneath the plate to push in the rolling bearing’s grease button. Things seem to be just a hair too tight. Perhaps I’m not on the right angle, but I tried multiple angles with the grease gun. Perhaps it’s because I cannot position myself underneath the rotary table as I have a sawdust basin in place. I have to attack the grease bearings from above the table. Anyone else have this problem or have people simply not greased their bearings ever again?
Matt

I know that this is an older thread, but you can get a longer tip for the grease gun. I just got one from Amazon that is 1.5 inches long, and replaced the .5 inch long tip that comes with the grease gun with it. It works like a charm.