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westpest
21st Sep 2004, 12:28 AM
Hey Joe

Next time you look at your VL175 can you tell me if the tailstock lines up exactly with the headstock-point to point that is. I'm asking because mine dosen't and I am wondering if this is why some of my turned pens are not even on the tube. I have to push the mandrel down a little about 2mm to lock on.

Good to see you back...

Dan F

DWFII
21st Sep 2004, 12:52 AM
I'm no expert, although I've turned a few pens, but several thoughts occur:

First, my lathe (a cheap China knock-off ) is very sloppy in the ways and the point of the tailstock center can be shifted an eighth of an inch either way before the tailstock is locked down. But knowing that I am able to always position the point to the left and that's seems to work. If you are turning between centers, it's point to point and as long as you either never dismount the wood or if you are sure to re-mount it exactly as it was, there should be no problems with the turning being off-center.

Second, if you have to spring the mandrel down it is an almost certain sign that the mandrel is bent. This can happen for a number of reasons...you tightened the tailstock up too much or perhaps you pushed too hard (dull tools?) when turning.

It's not the end of the world, however. Simply mount the mandrel in the headstock but not the tailstock. Turn the lathe on to a low speed. You will probably see the end of the mandrel making an eccentric arc as it turns. Rest a grease pencil on the tool rest and slowly bring it up so it touches the spinning mandrel. turn the lathe off. The grease pencil mark will be on one side of the mandrel. Now, you can (gently) bend the mandrel away from the high spot. Continue to do this until the mandrel runs true. Russ Fairfield has a section on doing this on his website and a whole section (two actually) on dealing with mandrels (as well as a slew of other stuff on making pens). Check out Russ Fairfield's Mandrel instructions (http://www.woodturnerruss.com/Pen12a.html)

BTW, I've trued my mandrel over and over...I actually expect to have to true it everytime I turn a pen...and since I started doing that I have yet to have a pen that's out of round.

Hope this helps....

westpest
21st Sep 2004, 01:26 AM
Thanks DWFII for the advice. There is a bit of a wobble in the mandrel and yes I probably have tightened it up to much. Having seen your album in another place to say that you have turned a few pens is indeed an understatement. I hope to be able to make as good a job of it one day.

On another matter, in some of your posts elswhere you mention micro-mesh sanding sheets-can you tell me the name of the manufacturer as I am having difficulty sourcing the product here in Oz.

Thanks again DanF

DWFII
21st Sep 2004, 05:33 AM
Dan,

I generally tighten my tail stock until the live center starts to turn with the mandrel...then just a tidge more until I can just no longer stop the live center from spinning with my fingers. Any tighter and you are almost certainly bowing your mandrel.

I have included a link for MicroMesh---that's its name. This company says it's "International" so even though there may be a wait to get the stuff to OZ you probably will be able to order it in. And, BTW, this may be the cheapest price for MM that I know of.

MicroMesh site (http://www.internationalviolin.com/main.cfm?custompage=micro_mesh)

Good luck...

Little Festo
21st Sep 2004, 09:43 AM
Hello Dan,

The Vicmark 175 has a swivel head. Could it be that your problem eminates from there. I've bee using a old Nova 3000 from time to time and the swivel head locking mechanisum is a bit sloppy so head and tail stock dosen't line up without a bit of extra care.

Just a thought.

Peter

westpest
21st Sep 2004, 12:26 PM
Hi Peter

The problem I may have is not sideways alignment but actually a drop of about 2mm. It's not just when the mandrel is in either, its there all of the time. I have reformed the mandrel to remove the "wobble" but if the drop is "built-in" then there will always be an angle when the mandrel is fitted ?? "won't there"??

Dan

PS Have they re-opened Jim-Jim falls yet. Three trips to Kakadu last year and couldn't get in due to big croc' in residence.

gatiep
21st Sep 2004, 03:22 PM
Dan

I cannot recall a alignment problem with my VL-175, however I'll get into the shed later this arvo and check out.
The mandrel can couse the tube to be offcentre in the turned wood, ie, the tube is not concentric in the turned wood which will be caused by a bow in the mandrel most likely due to too much pressure from the tailstock. The non concentricy ? will be more marked where the two sleeves meet.
If the centre height differ the turned work will be tapered if the tool cut parallel to the bed but not with the mandrel. In woodturning it is not as critical between centre turning as in metal turning where the tool follows a parallel line to the bed. In wood centre turning the eye looking at the 'horison' usually takes care of the slight discrepancy.
However if you mount a blank on the scroll chuch and bring the non aligned live centre up to the blank the live centre will actually scribe a circle onto the blank, the radius of which will be equal to the distance of misalignment.
I'm off to the doc now, but will get back to you about the alignment on my VL-175. Bet your bottom dollar if it is out, some body will get a roasting!!!!!!

Have a nice day. Hope the above makes sense.

:)

gatiep
21st Sep 2004, 05:57 PM
Dan


I just had a check on my VL-175 and it lines up perfectly. Make sure that the MT has no dust in it.
The VL-175 has an adjustment screw on the tailstock/bed slide on the far side which will line up the centre in a sideways plane and if both the sideways and vertical is out it will be possible to adjust it spot on. If only the vertical is out that adjustment won't correct it.

Have a good week....whats left of it

:)

westpest
22nd Sep 2004, 02:31 AM
Joe

I did as you suggested with the blank and the tailstock scribed a very nice circle of 3mm diameter. Does this mean it out by 1.5mm?. I have taken a pic to illustrate a bit better but because this is the first time I have posted a pic who knows what you will see.....

Dan

rsser
22nd Sep 2004, 09:22 AM
Guess so.

Checked mine and they line up.

Could your centre pin be bent?

westpest
22nd Sep 2004, 10:11 AM
Hi Ern

I have actually tried two different pin sets with same result..

dan

rsser
22nd Sep 2004, 10:50 AM
Hmm. And you've cleaned everything within reach. And a worn headstock locator wouldn't account for that vertical misalignment.

The adjusting screw that Joe mentions doesn't in fact go right through the base of my tail stock - I assume it's there just to hold the locking handle off the base.

What else could it be ... bent main shaft? Shudder. Buy or beg a dial guage and check the run out. Loose bearing(s)?

Think if I were in your shoes I'd be ringing Vicmarc in Qld; I've found them helpful in the past with a query about my 175 (and I might say that sometimes their machining ain't the prettiest). http://www.vicmarc.com/start.html

gatiep
22nd Sep 2004, 01:44 PM
Dan

Doesn't sound good.The pic doesn't look good either.
Another try: Screw some flat sheet of MDF on the supplied face plate. Screw the face plate in position on the headstock and bring the tailstock up to it. Do the test to see if you get a pinpoint or circle.
Whatever you do, do not get any marks on the tailstock!

Cya
:)

Dan
I have sent you a p.m. (personal message) check it and phone me. Joe

westpest
22nd Sep 2004, 06:00 PM
Ern

As this lathe is only two weeks old I don't think that wear is a consideration unless of course there was a manufacturing defect. I have spoken to "Vic" at Vicmarc about this problem and he is being most accomodating and leads me to state that their after sales service is nothing short of unbelievable. I hope I am not betraying a confidence by making this public but I think it deserves some recognition.

Vic has asked me to keep using the lathe until he comes to Perth in December when he will personally inspect the lathe at my residence (to damn heavy to cart around) and he will replace the lathe complete if it is found to be out of alignment.... like I said ...unbelievable... now I know why I bought Australian made..

Dan

John Saxton
22nd Sep 2004, 06:22 PM
Dan, not necessarily one to put a spoke in Vicmarc's reputation, but I seem to recall other folk posting yonks ago on problems they had with their lathe which caused them a bit of grief trying to resolve the issue at the time.

I may be wrong but it may have been something to do with headstock bearings...not that is necessarily true in your case.

I hope you resolve the issue so you can get turning soon.

Cheers :)

rsser
22nd Sep 2004, 10:22 PM
Dan,
Glad but not surprised to hear it - good news! But you could get your retailer out to look at it rather than waiting til Dec. Who'd you buy it from?
Johnno - doesn't ring a bell with me but my hearing isn't as good as it used to be ;-}
Cheers

westpest
23rd Sep 2004, 12:49 AM
Ern

The retailer has offered for me to take my tailstock in and line it up on their showroom lathe to see if my tailstock is lower than theirs so it will at least give me a starting point. If it is not then I'll take the headstock in and by this method of ellimination I should be able to resolve the problem a lot sooner. To my simple mind the easist solution would be a replacement headstock and tailstock that match but then there may be other factors involved? it can't be the bed .... or can it.... :rolleyes: :rolleyes:

Dan

rsser
23rd Sep 2004, 07:55 AM
Good to hear things are moving Dan.

The bed is cast then machined, as are the head and tail stock mating surfaces, and no process is completely error free. Got a good straight edge to check the bed?

The headstock shaft and tailstock quill are bored for the morse taper, and again, only a minor error in this will give you a misalignment.

If you have or can borrow a morse taper extension, the method noted above of wax pencil resting on the tool rest and marking the extension as it's rotated in the main shaft will indicate whether there's any run out at that end.

Looking forward to the next episode :-}

Boots
23rd Sep 2004, 09:47 AM
Hi,

I may be stating the obvious but it is possible as its new that there is some foriegn matter between the head/tail stock and the bed?

Boots

Alastair
23rd Sep 2004, 01:41 PM
Dan

Different lathe, but a suggestion worth looking at.

On the Teknatool site, they have a review on the Nova, done in the States, where they found the same problem, and it was traced to rubbish trapped in the packing grease between the swivel head and the lathe bed, as suggested below. Removing, cleaning with Kero, greasing and replacing solved the problem.

Worth a try. If they are physically of different heights, then it is a manufacturing fault that was not picked up before shipping, and they should be leant on to correct this immediately, not at their leisure!

Alastair

westpest
3rd Nov 2004, 01:33 AM
Thanks to all that took interest in my problem, I am happy to report that all has been corrected to my very great satisfaction...

Thanks to the supplier of my original lathe (who else but Carbatec Perth) I picked up a replacement yesterday which they gave ex their stock (to be replaced by Vicmarc) and it is spot on in every respect. I wish to publicly thank all of the staff at Carbatec Perth (without naming names as I am sure I would forget someone and end up in trouble) for all their patience in dealing with a westpest by name and nature. My thanks also to Vic at Vicmarc for the great after sales service and support. Needless to say I will be a lifelong customer of both of these establishments.

regards to all

Dan Faux :) :) :) :) :)

gatiep
5th Nov 2004, 02:18 AM
Good one Dan....glad you got it sorted out.

I just looked back...................bad news make headlines! Wen you originally posted the bad news, there was 17 posts in 2 days. Its been two days since you posted the good outcome and not even a whisper! Amazing. Well let me say: Good on Carba-tec Perth and on Vicmarc for sorting the problem out! Hope you have many years of happy turning mate

:)

Exalibur
5th Nov 2004, 04:50 AM
Just a shot, but I have heard of dirt getting into the Morse Taper causing mis-alighments.

Cheers!

John