Thread: Lathe turning off center = pens turning off center

I've got a similar prob with my Jet mini. Where your bearings seat, has it been surface ground or does it have machining marks?

Mine has been surface ground and the one closest to the bed is just a whisker out, very slightly off-centre. Not noticeable when doing bowls and larger items then pens but can see it straight away doing pens.

I am going to re-machine mine and sleeve it back to the original size on a metal lathe at a mates factory, in the meantime I do my pens on my other lathe.

It's hard to tell, but I'm not seeing any clear machining marks, so it may just be ground.

I've managed to knacker up both my shaft and my spindle lock so I'm a bit off.

The shaft seems very soft, is it supposed to be soft?

I have the ability to pick a lemon every time, literally. This is so wrong.

For the benefit of others who may be considering a purchase, can you name the brand / vendor? If it's still under warranty, do you plan to go back to the vendor, or do you think your fiddling may have removed that option?

Is the headstock belt-driven or direct drive?

If belt-driven, odds are the bearings are going. The amount of deviation at the tip centre can be up to the sum of any slack in the bearings. eg. if each bearing has 1mm side slop, you can easily have 2mm deviation at the tip. The lathe shaft shouldn't be noticeably soft, though!

If direct drive there's a better chance the shaft is bent, as it tends to be much longer.

Basically, there are four possible causes, in order of probability (as I see it):

• worn bearings.
• a bent shaft.
• incorrectly machined bearings, so the centre(s) isn't/aren't running true.
• incorrectly machined shaft, so the MT/thread and bearing centres aren't truly aligned.

Whatever the reason, I wish you luck with it. It's not much fun when your toys don't work properly.

Matt all of what Skew has said bout covers it. I wish you well and hope you eliminate the problem soon.
darren

Originally Posted by switt775

For the benefit of others who may be considering a purchase, can you name the brand / vendor? If it's still under warranty, do you plan to go back to the vendor, or do you think your fiddling may have removed that option?

Its a Rikon. It seems like a fairly well made lathe overall, more or less.
It is still under warranty, although although yes my fiddling may have removed that who knows although i do plan to see what they are willing to do to remedy the issue.

I did call them, and although I had heard they were fairly helpful, the tech I talked to didn't particularly help me much. He basically said, well, did you check this, and I'd say yes, did you check this, yes, did you check this, yes, did you take this off and did it change any things, yes and no it didn't, hmm, thats odd, well did you check this, did you know our dead center on the tail shaft needs to be changed if you are going to turn pens, yes.

Finally he suggested taking it back to where I bought it and exchanging it, but I'm fairly sure the exchange period is long over for the joint I bought it at.

By then I was tired of him having me check things I'd already checked and not acknowledging what my opinion of what the problem was, which although I know he has to trouble shoot a bit himself, I'm the one on the ground with the machine and I think I ought to know what its doing just a little better than him.

So I just said, hmm, ok, yeah, I'll take it back to the store, bye.

What I'm actually going to do is get the price list for the machine and see what it would cost to replace the bearings and shaft, and if it isn't too much I'll just do it and if it fixes it I'll call the chap back up and yell at him.

If that option is cost prohibitive, ie if they charge outrages prices for parts, I'll just replace it with a Jet.

Well, thats my plan lads, wish me luck.

The problem of inaccurate Lathe centres is very frustrating, because even if you can prove the lathe is at fault, it would mean packing all up and taking back and forth and then wait, wait, wait. I think it is the el cheapo production syndrome, so far I have struck the problem on my Jet pen lathes and Jet mini lathe, I know it is not correct, but to pack it and send it to NSW, and then wait! and I don't want to go through the bother, so if DJ is coming through one time, I will get his opinion, or if some other Melbourne based turner with experience wants to have a look sometime just PM me. I have resorted to stopping the lathe , and turning the blank half a turn on the mandrel as I near the end, to avoid oval turning, I may do that two or three times as i am close to the end.
So, putting price aside for the moment, what is a QUALITY mini lathe that one should consider. Amos

Mate also this may sound stupid but is your table solid. I had unsquare and warped and all sorts of trouble never dawned on me the table could be problem. Well hubby moved it so he could use the table I turned a pen on the new surface..Whoolaa fixed!! So something to think about
Toni

Originally Posted by Woodenink

The problem of inaccurate Lathe centres is very frustrating, because even if you can prove the lathe is at fault, it would mean packing all up and taking back and forth and then wait, wait, wait. I think it is the el cheapo production syndrome, so far I have struck the problem on my Jet pen lathes and Jet mini lathe, I know it is not correct, but to pack it and send it to NSW, and then wait! and I don't want to go through the bother, so if DJ is coming through one time, I will get his opinion, or if some other Melbourne based turner with experience wants to have a look sometime just PM me. I have resorted to stopping the lathe , and turning the blank half a turn on the mandrel as I near the end, to avoid oval turning, I may do that two or three times as i am close to the end.
So, putting price aside for the moment, what is a QUALITY mini lathe that one should consider. Amos

Amos I posted this not long ago regarding my Jet Mini would be interested to know what your trouble is http://www.woodworkforums.ubeaut.com...ad.php?t=57814

Amos sorry I did miss that your turnings are some what oval I have had similar trouble but thought it just bad placement of centres will have to be more vigilent to centring and watching for oval turnings.

Could this be that the head and tailstock are out of alignment.???

Hum time to do some measuring I think.

Ray

Originally Posted by lubbing5cherubs

Mate also this may sound stupid but is your table solid. I had unsquare and warped and all sorts of trouble never dawned on me the table could be problem. Well hubby moved it so he could use the table I turned a pen on the new surface..Whoolaa fixed!! So something to think about
Toni

True Toni adjustable feet should cure that bit but if the casting is doing torsion twists that much .

Ray, I don't want to steal Matt's post, so I will PM you, suffice to say your problems are same as mine. Amos

Originally Posted by Woodenink

The problem of inaccurate Lathe centres is very frustrating, because even if you can prove the lathe is at fault, it would mean packing all up and taking back and forth and then wait, wait, wait. I think it is the el cheapo production syndrome, so far I have struck the problem on my Jet pen lathes and Jet mini lathe, I know it is not correct, but to pack it and send it to NSW, and then wait! and I don't want to go through the bother, so if DJ is coming through one time, I will get his opinion, or if some other Melbourne based turner with experience wants to have a look sometime just PM me. I have resorted to stopping the lathe , and turning the blank half a turn on the mandrel as I near the end, to avoid oval turning, I may do that two or three times as i am close to the end.
So, putting price aside for the moment, what is a QUALITY mini lathe that one should consider. Amos

Exactly, its just a hassle to deal with it. I suppose the moral of the story is to always assemble the lathe in the store and check and see that everything is working right. I read that in a book....right after I bought my lathe.

I got the price sheet this morning, shaft is $12, bearings are $2.50. Handling is $7.00. Sorry, I'm just peaved that I'm being charged handing for, well, I'll quite complaining. The bottom line is for less than $25.00 I should be able to have it up and running again, hopefully with it functioning properly. If not, I'll take it back up to woodcraft and say, hey, this thing doesn't work, rikon said replace it. If they don't, I"ll buy a Jet, and use the Rikon for a boat anchor.

Originally Posted by Woodenink

Ray, I don't want to steal Matt's post, so I will PM you, suffice to say your problems are same as mine. Amos

PM recieved and replyed to use my thread and post away your woes Amos let them know at Jet your trouble it might save Matt88 from making the same mistake twice.

Matt88 if your reading this checkout my link regarding my Jet Mini troubles hopefully Amos will post his there also.

Originally Posted by Woodenink

So, putting price aside for the moment, what is a QUALITY mini lathe that one should consider. Amos

This one:

http://www.vicmarc.com/default.asp?contentID=514
Vicmarc Vl100 EVS. a nice $1500 +