Nova 1624 Spindle Movement

[Larry Packwood]

I have a Nova 1624 8 speed lathe and was getting some vibration that I did not have before so I got out my dial indicator to check for play in the spindle. Maybe 1/2 of a thousandth side to side but 14 thousandths end to end. I can actually hear a clunk when this happens. I have to pull/push hard on either the headstock (with chuck attached) or handwheel end to get this play, but obviously there is much more force going on when turning a 6"+ bowl. I can also see the spindle moving relative to the inner race of the bearing on the business end of the headstock. I have been back and forth with technical support at Teknatool but they resist letting you talk to an actual technician and you have to present the problem to a customer service person with no technical expertise who then relays it to a tech, who answers the first person who then gives you the answer. I also took videos of my testing procedures. The final answer was that everything was within specs. It seems to me that .014 is way too much play in a spindle, but I wonder if there are any 1624/44 owners out there willing to check this out on their lathes for the movement and particularly for the movement of the spindle relative to the inner bearing race. Thanks, Larry

 

[Dennis J Gooding]

I doubt that the end play in itself would cause any significant vibration. Did you check the side-to-side play at both extremes of the end play? If it remains small at both ends, I would check other causes such as a worn belt.

 

[Larry Packwood]

Dennis, thanks for replying. I had not thought about that but I will check it out. I have a spare belt and am still running the original. My thought was that if it is spinning and somewhere in the middle of the .014 run out and then I start cutting, when I hit a harder spot in the grain or a small knot, it might force the spindle to "bottom out" and bounce back, starting a cycle of repeated vibration. Not sure if I am making myself clear here but I will attempt to change the belt today and post a follow up.

 

[Mark Jundanian]

@Larry Packwood, I have a 1624 lathe. I don't completely understand your original post, but when I jiggle the spindle/hand wheel I can't feel or hear any play in the spindle, either laterally or in the rotation axle.

 

[Larry Packwood]

I'm talking about pulling on the spindle (you will need a chuck or something to pull on, or you can pull and push on the hand wheel) along the axis of the spindle directly towards the tail stock, then pushing in the opposite. Pushing and pulling 90 degrees to the axis of the spindle would show runout, of which I do not have much if any.

 

[Mark Jundanian]

Nope, yanked it in all directions and no movement I can see, feel, or hear.

 

[Larry Packwood]

Thanks. I was pretty sure that there should not be that much play. Also, in reading the directions for changing the spindle, I learned that the bearing has to be pulled off of the tailstock end of the spindle and I have free movement between the spindle and the inner race. I assume that bearings as well as the spindle will have to be replaced.

 

[Larry Packwood]

Problem solved, at least for now. I was attempting to remove the spindle pulley which Teknatool describes as "difficult to remove" when i had an epiphany. I put a straight edge across the tailstock side bearing and it was slightly proud of the casting. I gently tapped with a punch around the perimeter of the outer race and seated it properly and voila, no play! Not sure if it will stay seated since the bearing is supposed to be pressed onto the spindle and it is not. that indicates to me that either the spindle or the bearing (or both) have some wear. Nonetheless, there is little to no side to side play right now. Thanks for all of the input and happy turning! Larry