# Help with runout on new lathe



## Burbs (Jul 11, 2016)

Finally took the plunge and bought a Delta 46-460 midi.

Anyway, got the lathe about 2 weeks ago and have been playing around doing spindle work between centers and was having a ball so bought a nova g3 chuck off of Amazon. Noticed while using it I had some wobble even when I had everything trued up, but it wasn't much and crank up the lathe another 100 rpm and it evened out. Did a couple candle holders and small bowls and worked good except for that annoying wobble. Turned a couple bigger (9 inch) platters and noticed the edges weren't quite the same on both sides, so with that and the wobble, I got out the dial indicator and checked the inside of the spindle and it is dead on at the end. Put both the Nova chuck and the faceplate that came with the lathe on and both have about .001" of runout. 
So 2 questions?

1. Is .001" enough to cause that slight wobble?

2. Is it worth trying to deal with Delta customer service to try to fix it?

I'm guessing the threads on the spindle are a bit off? Both the g3 and the faceplate thread all the way tight.


----------



## Nubsnstubs (Aug 30, 2013)

.001" is nothing to worry about. My thoughts are the wobble and uneven sides you are noticing on the platters is the wood moving. ................... Jerry (in Tucson)


----------



## Wildwood (Jul 22, 2012)

I agree with Jerry .001 not much to worry about. Not sure the lathe is the problem if you only see the wobble with wood mounted in the chuck mounted on the lathe. Would mount both chuck and faceplate on the lathe without wood to see if have the same wobble at certain speeds before blaming bad spindle threads.

You did the right thing adjusting speed to smooth out the wobble!

You don't say if your chuck came with threaded insert installed (direct threaded) or you installed the insert yourself.

My lathe shakes/wobbles when mount a heavy unbalanced wet blanks on the lathe whether turning between center, blank mount in my chuck or on a faceplate. Once get the blank round and balance lathe shaking/wobbling subsides. This can also happen with unbalanced dry or partially dry wood too! Some species of wood more of a problem turning due to drying as we turn it.


----------



## Burbs (Jul 11, 2016)

The wood moving I can definitely understand as being the issue with unevenness especially since the wood came out of the woodpile a couple weeks ago and is still not stable with my warm dry shop.

The uneven wobble with only the Nova chuck on is not something I should be concerned with? It happens from around 1200-1400 rpm or like 4 1/2-6 on the middle belt position for anyone familiar with the 46-460.


----------



## Burbs (Jul 11, 2016)

The nova chuck is not the one with the insert, which in hindsight was probably a mistake. Lathe has that slight wobble with only the chuck or faceplate on, no wood on them.


----------



## Lazyman (Aug 8, 2014)

If you pull or push from side to side can you feel any movement or play? .001" could just be imperfections in the surface finishes of the chuck and face plate. If it is really out, you should see the exact same negatve deflection (or half of of the total anyway) on the exact opposite side. Are you measuring on the sides or the faces? If you mark the spot on the spindle does the .001 show up on the exact same place between both chuck and FP?

I agree that .001 should not be enough to affect results (you are turning wood after all) but if you can feel movement in the spindle, it will just get worse. If there is no movement, I would not worry about it.


----------



## Burbs (Jul 11, 2016)

No play in the spindle that I can feel. I was measuring the runout from the side. Will have to do some more measurements tonight when I get home.


----------



## HokieKen (Apr 14, 2015)

It depends on the runout. If the runout is consistent down the full length of the chuck and reads .001 on your indicator, then it's .0005 off center. No worries there. However, if you measure more or less runout at the back of the chuck than at the front (assuming chuck is consistent diameter), then it's off-axis as well. No biggie at small diameters but, when you load up larger diameter blanks, the runout will be compounded due to the axial error.

If you only see the wobble at a certain speed range though, your setup is hitting a resonant frequency. Add some weight to your stand or put some rubber pads under the feet and see if that eliminates the issue or changes the speed range in which it occurs.

Just my thoughts. Hope it helps!


----------



## LeeMills (Nov 2, 2014)

At .001 I don't think it is anything to be concerned about. I assume most better chuck have similar standards and Nova's are <.004. It may be the chucking method(s) more than the chuck or faceplate.


----------



## kelvancra (May 4, 2010)

Then there is the obvious. If I put a spindle in with a round end, versus one with a square end, or if I am clamping down on soft wood, I can throw the right end off center. As such, I try to bring the tail in, when I can, if only for set up.

I'm a newbie, so I could be off base on this. Input?


----------



## HokieKen (Apr 14, 2015)

Always a good idea to use the tailstock whenever possible to help line things up or stabilize your blank Kelly.


----------



## wormil (Nov 19, 2011)

I don't think most people would consider .001" = "wobble", that's 1/4 the thickness of a piece of paper, so if that is all you are measuring it's probably the wood, especially since it's firewood. I measure runout by chucking a large forstner bit and putting the indicator on the shaft. The total runout will include the spindle, chuck, and drill bit shaft but it should be good enough for a wood lathe. I found a .005" difference between clean threads and dusty threads and total runout was about .019" with dusty threads, .0014" with cleaned threads. That was on my Comet II which had a lot of miles on it and needed new bearings. I haven't done the test with my Delta Midi. I wish I had repeated the test on my old Delta 46-111 after swapping bearings and before selling it. I'm not an expert, but here is how I did it:
http://thewoodknack.blogspot.com/2016/03/will-home-made-spindle-washers-cause.html

It threw me when I first started that I would turn something round, stop for a few minutes and when I started again it would be wobbling because the wood had moved. We tend to think of wood movement as something that happens seasonally but it happens quickly too, like when your kerf closes on a tablesaw because the wood is improperly dried.


----------



## LeeMills (Nov 2, 2014)

Another possibility may be the chucking method (forming the tenon or recess).
Anytime I turn between centers and then chuck up there is always runout, nothing to do with the machine just the way wood moves. Everyone I know assumes they will have to re-true after reversing.
If you add small improper mounts the problem can get large very quickly.
If you haven't studied them (or others) I suggest the three videos on chucks, tenons, and recesses by Stuart Batty.
There is 30+ on his list but the three are easy to find. Just a simple thing such as not have a completely flat area for the top of the jaws to seat against can cause major problems.
https://vimeo.com/woodturning/videos/sort:alphabetical/format:thumbnail


----------



## Burbs (Jul 11, 2016)

Thanks for all the great responses guys. I will get out the dial indicator and take some more readings because honestly I only attached the magnetic base and measured the side of the chuck and faceplate and the inside of the spindle. Have a lot more info now too that didn't show up on my google searches so thank you all again. I'll post again after doing some more measuring.


----------



## Nubsnstubs (Aug 30, 2013)

You said the problem is only when the chuck is mounted. Check the flat/shoulder on the spindle that the chuck bottoms out on if it's a direct threaded chuck. There could also be a small burr on the back of the chuck . ....... Jerry (in Tucson)


----------



## Burbs (Jul 11, 2016)

So a little bit of dust build up behind the chuck, cleaned it up and am measuring less than .001" of runout on the side of the chuck. Front of the chuck there is virtually none. Dial inductor doesn't really even move. Still have that annoying vibration in between 1200-1400 rpm but under that or over that it disappears. 
I'm probably going to have to go with the resonant frequency thing that HokieKen said. I built the stand "heavy" knowing I would probably need the weight and have my slow speed grinder built in under the bench with one of those fold down mixer racks for even more weight so guessing it's around 300-400 lbs with the lathe on. I'll maybe try some rubber underneath and tighten the bolts down and see if it goes away. 
Thanks again for all the help all. I learned a ton that I wouldn't have without this great community.


----------



## OSB (Dec 16, 2016)

The vibration is probably a balance issue.

A static balance isn't good enough and dynamic balancing is usually more than a tool maker would do unless it's a high rpm precision tool, a wood lathe probably doesn't qualify.

I tried making a rotary spark gap which was a pair of aluminum plates sandwiching a G10 disk. Everything was symmetric and machined with some care, I doubt any dimension was more than 0.002" off of the design. After that I took it to get balanced at 1,800 rpm. The machinist mounted it, spun it up to a couple hundred rpm and then told me nope.

It is not easy to get anything spinning smooth at high rpm, even when you try to make the CG concentric with the axis of rotation.


----------



## HokieKen (Apr 14, 2015)

Could be too that when the lathe operates in that speed range that it induces harmonic oscillation of the fold-down mixer rack. Next time you get the vibration, try clamping your grinder down tight to see if that changes anything.


----------

