out of round

[markgum]

I know this has been discussed before, but let me share my recent findings and why I'm confused.
Turning between centers.
pen is out of round
looked at the points on the 60 degree centers made sure they lined up
noticed the bushings were not 'flat' against the pen ends. I was sanding them on my disk sander as it was a 'kit' pen and I was nervous that a pen mill would 'rip' out the designs.
I tried again, new kit, and took my time making sure the bushings were seated good against the pen blank. still out of round. so I sanded it down to be flush with the bushings. was better but was still out of round.
Today, I took a 2x2 turned it round between centers. Turned a tenon on it, and mounted it in the nova chuck, put the drill chuck in the tail stock and drilled. Tried to open the hole a bit more with the bowl gouge and the wood snapped. It was thinner on one side.
Something is out of kilter on the lathe, I think. Any ideas?
I have cleaned out the tapers.
next, I'm just going to put a 2x2 in the chuck and drill it. No turning it round.
It is a Jet 10x14 lathe.
thanks for any pointers.

 

[louie68]

I am having the same problem with my Jet 1014 vs. When I turn using centers my pen turns are out of round also. If you figure it out please let me know.
Thanks, Louie56

 

[ed4copies]

Mark said:
Today, I took a 2x2 turned it round between centers. Turned a tenon on it, and mounted it in the nova chuck, put the drill chuck in the tail stock and drilled.

OK, when you mounted it in the chuck, how did you make certain it was perpendicular to the headstock?

Seated to a "flat" above the tenon?
Other method?


Also, how did you assure yourself you were "aiming" the drill at the center of the moving blank? How long was the drill bit?

All this will help in establishing where the problem is,
thanks!!

 

[spnemo]

Have you checked to see if the ways are warped or twisted?

 

[aggromere]

If your tailstock & Headstock line up exactly and you have Johnny CNC's steel TBC bushings the only thing I can think of is you have some kind of crud on the MT2 of the centers or in the holes they go in and it is giving you a false line up between points. If you are not using Johnny's bushings, then it may well be a bushing problem.

Also, when you line up the centers the tailstock is very close to the headstock. You could have something on the lathe ways where it actually sits when you are turning.

Those are just guesses on my part. For what it's worth, somedays things work fine for me and others not so fine.

I have no idea about your expanded a hole with in a small piece of wood with a gouge. Drilling is a whole nother issue from TBC in my opinion. Lots of things can happen to screw up drilling a blank, I know because I have done it badly in the past. Now I just drill using a collet chuck after rounding the blank, center drill and drill one or two smaller, but increasing in size holes before I drill the final pen size hole I want. Not sure which of those steps makes it better, but haven't had any issues with drilling since I started doing that.

 

[jttheclockman]

Did you do the point to point check and turn the lathe on at a slow rate of speed. You need to start there. If they are dead on then you need to go to the bushingings. If you are sanding on a disc sander you need to have that tube 90 degree to the sander on all axis. You did so many different things you need to slow down and take them one at a time and investiagate your each step.

 

[DozerMite]

I have a Jet 1014 and mine used to do the same thing.

The head and tailstocks line up perfect when pushed together, but as you move the tailstock down the ways, check if there is any movement between the ways. If so, this can change the alignment between the head and tailstocks. It can get cocked between the ways or it could be to one side or the other and cause misalignment.
This causes issues when drilling also.

I found out which side I needed to place the tailstock to keep it lined up. Now I don't have any more problems.

 

[Woodlvr]

I have the same issues but am not sure how to check the alignment after the heads are farther apart. Last year I put a new set of bearings in to stop a ticking noise but it came back. I am reluctant to drill on the lathe because of this issue.

 

[markgum]

yes, I need to slow down and evaluate everything.
I did turn the headstock by hand with the center's installed and it remained spot on for point to point.
I may not have had the 2x2 perpendicular, (looked good, but...) The drill bit was a forstner bit and I only drilled about 2 inches deep. As far as aiming. I didn't; I turned the lathe on, and eased the tail stock up to the wood and started cranking it in.
I have cleaned the taper 3 times.
I will put a level on the ways tomorrow, and I will take my time tomorrow and figure this out.
Thanks everyone for the input. Interesting that Louie56 and DozerMite said they have similar problems with their 1014.

 

[jskeen]

You gotta keep in mind, just because the tips of the centers touch perfectly when the tailstock is pushed all the way up, don't mean that the center of the MT bores are actually aligned at that position, just that the tips end up in the same spot. It certainly doesn't say anything about the alignment when the tailstock is somewhere further down the ways. I don't really know how one would go about checking that alignment, personally. I have heard that somebody out there makes an alignment gauge for lathes, that is basically a double ended morse taper. But I've never seen one, and i'm not sure how it would work anyway.

But... In the last hour, between starting this reply and now, while lying in the dark trying to get my 3 year old daughter to sleep, I thought of something that might work. However to avoid hijacking this thread, I think I'll post it separately.

 

[ctubbs]

Would using a bore sighting laser work to check alignment? A machine shop could fit it into an MT. Just a thought.
Charles

 

[jttheclockman]

One thing that has to be remembered here a wood lathe is not by far a precision tool. I suppose you could take a long straight rod and using a collet chuck you can extend the rod to the far reaches of the tailstock and if you have a center point on this rod you can line that up with the point on the tailstock and keep moving it in as you allow the rod to go into the headstock.

 

[jskeen]

One thing that has to be remembered here a wood lathe is not by far a precision tool. I suppose you could take a long straight rod and using a collet chuck you can extend the rod to the far reaches of the tailstock and if you have a center point on this rod you can line that up with the point on the tailstock and keep moving it in as you allow the rod to go into the headstock.

That's sorta what I posted just now, but that is really showing you the alignment of the spindle threads with the tailstock bore, not necessarily the mt bore in the headstock's alignment to the tailstock bore. Of course, it's the same piece of steel, so it might make absolutely no difference, but then again, it might.

 

[jttheclockman]

http://www.packardwoodworks.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=lathes-acc-mrstool

You have to remember there are so many parts that can be off on a lathe. If the male and female parts of the tapers themselves aren't cleaned. There is play in the tailstock every time you go to lock it down after you slid it to its place. These double tapers are somewhat good but again not the cure all. Even using a laser won't get you there all the time because of the slop in the parts. Want percision get a metal lathe.

The thing is if you are seeing those kind of results that drastically then there is something very wrong. Start with different bushings.

By the way don't run the lathe with this installed. Just thought I should throw that out there. Never know.

 

[markgum]

I've thought about obtaining one of these but might be able to cobble one together a little less expensive.

http://cgi.ebay.com/Lathe-Spindle-R...785?pt=LH_DefaultDomain_0&hash=item2eb1d54d39

 

[jp_white]

Temp work a round?

This may not help but...... I use homemade corian bushings on my shopsmith and have found that somehow the blank is perfectly round on my tailstock side. I simply make sure that my finishing work is done with each side towards the tailstock. Seems to work for me until I can figure out something better.

 

[Russianwolf]

take a piece of wood and drill a hole through the center and mount a laser pointer in it. Fix this to either the Headstock or tailstock (using the threads on the spindle or making it a morse taper, or collet chuck). Done right, it will always point to the center of the other item.

No worries about sagging bars, or how long your bed is.

 

[markgum]

found out the front way is about 1/16" inch lower than the rear. Tried to adjust the legs on the stand and SNAP. Broke one of the adjustable feet. yeah potty mouth words came out. Now, it dances across the garage with no wood on it at all.

 

[KenV]

If you are working between centers -- it matters not a whit if the headstock and tailstock line up as long as what is in the middle is RIGID. How did things get turned before we had fancy cast iron gear -- the old treadle lathes.

If what is between centers flexes, it cannot be circular on the axis --

So look for alignment that is changing and flexing/moving. The ends of the blanks are the obvious place to start -- crud in the tubes might be a close second.

 

[jttheclockman]

One of the first rules of setting a lathe up is that it must be level and this could cause out of round problems.

Ken

Normally that is true when turning a spindle, but in this case it is a pen tube which has fixed ends and they must be true when inserted in bushings. If they are not and spun on an axis that is not true they will be out of round in conjunction with the tube which is round. That is my story and I am sticking with it.

 

[mtgrizzly52]

Here's a silly question, and I'm sure you've done all of this, but have you followed the instructions in Johnnycnc's video about checking runout? The link is: http://www.youtube.com/watch?v=16xBV3PggQI

I thought I was having a similar problem, but it turned out I had a burr in my headstock which was goofing things up....burr gone, round pen blanks....until the next problem crops up.

Rick (mtgrizzly52)

 

[Nate Davey]

One other thing to consider is whether you lathe is level, left to right and front to back, if it isn't it could be slightly twisted and this will through off the alignment

 

[louie68]

1014 Jet not round

Hello Mark curious what did you find out about not rounded on Jet 1014 lathe Im having same problem when i don't use mandrel **** only when turning on centers im having the problem, also my tail travels after i lock it up, if you fine answers please get back to me, much appreciated, thks, LOuie56

yes, I need to slow down and evaluate everything.
I did turn the headstock by hand with the center's installed and it remained spot on for point to point.
I may not have had the 2x2 perpendicular, (looked good, but...) The drill bit was a forstner bit and I only drilled about 2 inches deep. As far as aiming. I didn't; I turned the lathe on, and eased the tail stock up to the wood and started cranking it in.
I have cleaned the taper 3 times.
I will put a level on the ways tomorrow, and I will take my time tomorrow and figure this out.
Thanks everyone for the input. Interesting that Louie56 and DozerMite said they have similar problems with their 1014.

 

[jttheclockman]

Hello Mark curious what did you find out about not rounded on Jet 1014 lathe Im having same problem when i don't use mandrel **** only when turning on centers im having the problem, also my tail travels after i lock it up, if you fine answers please get back to me, much appreciated, thks, LOuie56

yes, I need to slow down and evaluate everything.
I did turn the headstock by hand with the center's installed and it remained spot on for point to point.
I may not have had the 2x2 perpendicular, (looked good, but...) The drill bit was a forstner bit and I only drilled about 2 inches deep. As far as aiming. I didn't; I turned the lathe on, and eased the tail stock up to the wood and started cranking it in.
I have cleaned the taper 3 times.
I will put a level on the ways tomorrow, and I will take my time tomorrow and figure this out.
Thanks everyone for the input. Interesting that Louie56 and DozerMite said they have similar problems with their 1014.

Louie

I am sure you probably read through some of the suggestions within this post so I won't hit those again. But the locking nut for the tailstock has always been a problem on the jets. There was someone here that made a replacement here for them and I can not remember who it was. You may want to put those words in the search box and see what comes up. I am sure they will point you in the right direction. Good luck.


PS I just did a quick search and long and behold I asked this question some time back. There are some good answers in there. http://www.penturners.org/forum/showthread.php?t=37644&highlight=tailstock+slippage

 

[titan2]

Hello Mark curious what did you find out about not rounded on Jet 1014 lathe Im having same problem when i don't use mandrel **** only when turning on centers im having the problem, also my tail travels after i lock it up, if you fine answers please get back to me, much appreciated, thks, LOuie56

yes, I need to slow down and evaluate everything.
I did turn the headstock by hand with the center's installed and it remained spot on for point to point.
I may not have had the 2x2 perpendicular, (looked good, but...) The drill bit was a forstner bit and I only drilled about 2 inches deep. As far as aiming. I didn't; I turned the lathe on, and eased the tail stock up to the wood and started cranking it in.
I have cleaned the taper 3 times.
I will put a level on the ways tomorrow, and I will take my time tomorrow and figure this out.
Thanks everyone for the input. Interesting that Louie56 and DozerMite said they have similar problems with their 1014.

Try JohnnyCNC......that's where I got mine!



Barney

 

[titan2]

Hello Mark curious what did you find out about not rounded on Jet 1014 lathe Im having same problem when i don't use mandrel **** only when turning on centers im having the problem, also my tail travels after i lock it up, if you fine answers please get back to me, much appreciated, thks, LOuie56

yes, I need to slow down and evaluate everything.
I did turn the headstock by hand with the center's installed and it remained spot on for point to point.
I may not have had the 2x2 perpendicular, (looked good, but...) The drill bit was a forstner bit and I only drilled about 2 inches deep. As far as aiming. I didn't; I turned the lathe on, and eased the tail stock up to the wood and started cranking it in.
I have cleaned the taper 3 times.
I will put a level on the ways tomorrow, and I will take my time tomorrow and figure this out.
Thanks everyone for the input. Interesting that Louie56 and DozerMite said they have similar problems with their 1014.

Louie

I am sure you probably read through some of the suggestions within this post so I won't hit those again. But the locking nut for the tailstock has always been a problem on the jets. There was someone here that made a replacement here for them and I can not remember who it was. You may want to put those words in the search box and see what comes up. I am sure they will point you in the right direction. Good luck.


PS I just did a quick search and long and behold I asked this question some time back. There are some good answers in there. http://www.penturners.org/forum/showthread.php?t=37644&highlight=tailstock+slippage

Sorry.......wrong 'Quote'....

Try JohnnyCNC......that's where I got mine!



Barney