about to throw in the towel...(kinda long)

[dachemist]

This is probably going to be kind of lengthy so I'd like to apologize in advance.

I have been unable to eliminate out of round issues on the pens I turn (I'd also like to apologize for bringing this topic up again). I've gone through the archives and I'm pretty sure I've read all the posts on this topic (as well as tried all the suggestions contained therein) but nothing has worked. I'm hoping someone will have a flash of inspiration after reading this (I have a thought or two that I'll mention a little later). First, here's what I've tried (not in any particular order):

1) Bought a bench top drill press (not really any better than using a hand held drill, at least in my hands) and a drill press vise (non-self centering). Returned the vise, bought a self-centering vise. Returned the drill press, bought a full size drill press (more on that later).

2) Discovered the centering vise jaw assembly had a tendency to bend toward the table when drilling, apparently causing the holes to be drill at an angle through the wood (though the offset should get turned out and not matter). Cut a piece of wood to support the handle of the vise and keep the jaw assembly from moving.

3) Realized mandrel was bent and replaced (3 times)

4) Noticed headstock and tailstock not lined up properly casuing the mandrel to visibly bend when advancing live center. Shimmed the tailstock with a piece of sandpaper, mandrel did not visibly bend.

5) Bought new (60° live center).

6) Replaced cheap PSI lathe w/VS Jet Mini.

7) Bought new tools (to replace cheap ones from PSI starter kit that came with 1st lathe). Bought low speed grinder from Woodcraft and Wolvering jig to sharpen new tools.

8) Gave up on MT mandrels, bought Beall collet chuck plus new mandrel rods (A & B from AS), plus pen kits for the B rod.

9) Bought new bushings, drill bits, digital caliper, new vise (the wood one from AS.

10) Finally called Jet about the tailstock issue, tried the 2 replacement tailstocks they sent me, then called Woodcraft (I'm hoping to pick up my replacement lathe tomorrow).

11) Tried sharpening my pen mill...oops...bought replacment cutter head for pen mill. Bought a disc sander from HF (the local store had a 1 day sale, $99 for the 12in sander, I figured it was worth a try), disc sander jig from PSI (unfortunately I don't have the equipment to try making the one in the article from Jay). Going to return both and go back to the pen mill.

If you've read this far, thank you for your patience.

I think one of the problems was buying a HF drill press (maybe I just got a bad one, that sort of luck runs in my family). I've tried using larger pieces of wood to allow enough to compensate for turning out the offset from the angled hole. My latest thinking is that the vibration caused by the (greater) uneven weight distribution is bending the mandrels (perhaps that should have been obvious to me sooner).

Also I'm wondering about the spindle alingment as well. I was sanding the outside of a small bowl (< 6" in dia) and noticed that the bowl and the handwheel were both wobbling quite a bit. I thought maybe the bowl was somehow out of balance (as a side note the few bowls I've turned have been "out of round" as well). I removed the bowl and faceplate and turned the lathe on again and the wobble was still there even with nothing on the spindle.

I'm going to give penturning one last try befor calling it quits. I want to try to eliminate as many issues as possible to make it a fair test. If I'm the problem I'm prepared to accept that. It would be a shame though, I think I'm finally starting to get the hang of finishing with Enduro...

Thank you againg for reading this, and for any advice.

Mike

 

[Scott]

Mike!

That is truly an amazing story! You have really been through it! I have to admire your persistence! I'm not sure I would have gone as far.

If you don't mind, allow me a few comments. When you pick up your new lathe, you may see an improvement. From your description it sounds like the headstock spindle was not aligned properly. Jet makes a good lathe, but there is always the possibility of a lemon. Lets hope your replacement one is perfect!

The new mandrels and the Beall collet chuck should give you the best holding available on the market. The new 60 degree live center should hold the other end just fine. If everything on the new lathe lines up, you should be good to go.

Now don't be offended, but how much out-of-round have you been experiencing? If it's noticeable, it's too much. If you have to look really close to see it, you may be close enough.

Most any mandrel can have a tendancy to "whip" a bit. If your pen seems to be round at the two ends, and only out of round in the middle, that is probably just some whip. You may want to turn your pens one blank at a time. It's easy to shorten the mandrel using the collet chuck so only enough to fit the one pen barrel is out. That should greatly reduce your whip.

But I really think that if you get a new lathe like you're saying, that should make a big difference! Man, I hope so, you deserve a break!

Good Luck!

Scott.

 

[ldimick]

Mike,

Wow!

I think Scott hit it right on the head. It sounds to me like the problem might be in the headstock. It sounds out of round. You have tried everything else. Does the headstock of the mandrel spin true?

 

[Easysport]

I sure hope its the lathe thats the problem. Watch the pressure you use when cutting as excessive pressure can bend the rod. You have way more persistence's than I would have had. The lathe and everything with it would have been in the trash by now. I think you will get the problem solved[8D]

 

[C_Ludwigsen]

MAN Mike, that is amazing what you've been through. Please don't be offended by my question, but how much pressure are you putting on the mandrel from the tailstock live center?

Also, I usually detect a slight out-of-round with a couple of my mandrels. While turning, once I am almost to the bushings, I stop the lathe, loosen the mandrel nut, rotate the blanks on the mandrel 180 degrees and tighten the nut. I then finish the cut.

It really has wiped out any remaining out-of-round.

Hope all this helps. Of course, without being in your shop and seeing the problem, we are mostly just guessing from your description and our experiences.

 

[its_virgil]

Two things you did not mention jumped out at me. How tight are you tightening the brass nut on the end of the mandrel and how tight are you cranking on the tail stock. Tightening the brass nut on the mandrel can bow pen blank and too tight on the tail stock can bow the mandrel and both of them too tight can compound the bowing and out of roundness. Some disagree with me on this, but it happens...been there. I went through most of your story when I first started and found the brass nut too tight and the tail stock too tight was my problem. BTW, I love my HF floor model drill press and would not go back to a pen mill over a disk sander. But the PSI squaring jig is not the jig to use. Any way, good luck with your venturre and I hope you find the culprit and continue turning pens.
Do a good turn daily!
Don

 

[TomServo]

Originally posted by its_virgil
<br />Two things you did not mention jumped out at me. How tight are you tightening the brass nut on the end of the mandrel and how tight are you cranking on the tail stock. Tightening the brass nut on the mandrel can bow pen blank and too tight on the tail stock can bow the mandrel and both of them too tight can compound the bowing and out of roundness. Some disagree with me on this, but it happens...been there. I went through most of your story when I first started and found the brass nut too tight and the tail stock too tight was my problem. BTW, I love my HF floor model drill press and would not go back to a pen mill over a disk sander. But the PSI squaring jig is not the jig to use. Any way, good luck with your venturre and I hope you find the culprit and continue turning pens.
Do a good turn daily!
Don

I can testify to this happening! I have problems with the mandrel bending every time I tighten the nut (I use a mild steel hex nut) I usually have to wiggle it around in the collet to straighten it up.. I wouldn't have a problem if my collets weren't so specifically sized (Taig lathe) - the B mandrel doesn't fit the 9/32 or the 5/16 collet very well..

I have had very much better success when I turn to about 1/8" from final size, then pull my tailstock back, loosen the nut some, tighten it just enough, and check the mandrel for straightness.. a PITA but it works wonders..

On the drill issue.. I have found the Berea parabolic bits to drill fantastically straight.. and I use a hand drill, clamp the blank to my workbench, and drill the entire blank before I cut the seperate barrels. I've recently switched to chucking the bit into my lathe chuck, and drilling on my cross-slide. I think I'm getting a drill press for christmas I've also found that if you let the bit pull you into the blank, the grain will push it around more..

 

[Randy_]

Originally posted by dachemist
<br />.....10) Finally called Jet about the tailstock issue, tried the 2 replacement tailstocks they sent me, then called Woodcraft (I'm hoping to pick up my replacement lathe tomorrow.....

Does the above imply that you have a Woodcraft store close by?? If so, I would suggest you invest another pile of dollars on a pen making course at the store and use "YOUR" lathe. They ought to be able to figure out what is wrong and how to remedy it. I don't mean any disrespect toward you; but it is pretty unlikely that all of that equipment was defective in some way......much more likely that there is a problem with your technique. A trained turner looking over your shoulder is probably the best solution.

Do you have a wood turning club in your area?? Or maybe you could post your city and find an IAP member close by who would be willing to help?? Good luck!!

 

[Daniel]

Mike,
With your description of the hand wheel wobbling, I agree with the idea that it is the head stock in your case. that would also explane why non of the other fixes have worked. i don't here of problems like this very often so chances are good your new lathe will not have it. Anouther problem I see in all this is lack of confidence in your equipment. I can't really blame you at this point. Drill presses, vises, barrel trimmers, disc sanders, etc. really do work. so once you get the wobble solved take a deep breath and give them all a fair open minded try again. I also don't believe all your equipment could be defective. Trying to figure out what normal preformance is without ever having seen a correctly operating machine would be a bit difficult though. as an example, for me a woobling head stock would stand out like a sore thumb. because i am very used to a smooth running one. I have gotten to the point I can feel out of round through my turning tools. (I have real tail stock issues with my lathe).
but this is after making hundreds of pens an other turnings.
I second Eagles idea of finding anouther turner somewhere and seeing for yourself what proven good equipment preforms like. it will help in seeing what is not right about yours.
By the way, I don't believe the problem is you either. Children are able to turn pens under a watchful eye and an experienced hand.
I honestly think that if anouther turner such as Ed, Tom, Eagle or any of the other really experienced turners here. Could walk into your shop. they would spot the problem in a heart beat. be able to get it fixed for you. and you would be off making round objects out of square pieces like they do. An uncommen problem along with unfamiliarity is a bad combination.

 

[BillATsetelDOTcom]

My "out of round" was caused by bad bushings...just a thought.

 

[RussFairfield]

That disc sander could be the problem if the ends of the barrels aren't square with the bore of the brass tube. If set up properly, sanding can be the best way to trim the ends; but if not, it is the worst.

You can reduce the effect of the ends not being square by tightening the nut on the mandrel for turning the barrels to round, and then backing off on the pressure to where there is just enough to hold everything together for turning and sanding.

 

[Rifleman1776]

Without 'hands on' observation, this is difficult to diagnose. Perhaps, when you pick up the next lathe, the store might allow you to unpack and inspect right there, with their own people watching. With all the jillions of the Jet minis being sold, I wouldn't be surprised if the Chinese factories might be letting quality control slip in favor of meeting quantity demands. Good luck.

 

[Mudder]

When you put the pen together is there a noticeable misalignment when you operate them?

Looks like you have received a lot of very good advice. About the only thing I can add is when you tube the blanks what size drill are you using? I have a buddy who was making a batch of slimlines and he forgot to get the proper drill. Not possessing anything more that a 1/16-increment index he used a 5/16" drill to do his holes and poly glue to glue in the tubes to fill up the "extra space" and wound up with something like the picture I have below:

The interesting thing is that the pens worked great because everything was aligned and his error was one of concentricity and not out of roundness. (at least the ones that he did not blow out worked great) The picture I put up illustrates an example of perceived out of roundness. In actuality none exists because the center point of the tube and the outside diameter are the same.

I would also take a closer look at what Don (its_virgil) has written about the tightness of the nut and tailstock because I have ruined a couple of pens by over tightening. I have also ruined a blank or two by not having the ends squared properly.

I hope you can understand my ramblings. If the pen is indeed out of round than something is causing it to not spin true upon its axis, but if the assembled pen works properly than you may have a condition of perceived out of roundness due to a hole that is bigger than the tube and the tube is settling to one side while the adhesive cures.

 

[Randy_]

Originally posted by Daniel
<br />.....I second Eagles idea of finding anouther turner somewhere and seeing for yourself what proven good equipment preforms like. it will help in seeing what is not right about yours.....

Daniel: Eagle has lots of good ideas about pens and some not so good ideas about other things; but finding an experienced turner to help was actually my idea. I'm sure neither he nor I appreciate the confusion. [][}][]

 

[Dario]

Mike,

You sure wen't through a lot and like most, I do admite your persistence too.

I agree that your best bet is probably to have someone check your setup and procedure. Stay there...I am sure the worst is over. []

 

[Thumbs]

Good Grief! You don't live on Elm Street, do you? Sounds like a real nightmare anyway![:0]

 

[dachemist]

Thank you everyone for the replies and words of encoruagement.

I see I forgot to mention a few things in my first post. I'm going to try to keep them in the order of replies.

I have tried turning one blank at a time, when the collet chuck and mandrels (from AS) came they weren't long enough to put 2 blanks on at the same time. To me the mandrel seemed way too unstable when it was extended far enough to hold 2 blanks. When I first started in March I know I was tightening the tailstock too tight. Now I turn the lathe by hand and advance the tailstock until the live center just starts to make contact and spin. I bought one of the cheaper HF drill presses and have noticed I can "wiggle" the spindle a bit from side to side by hand (I'm terrible at judging how far it moves, my best guess would be 1/16" - 1/8", most likely closer to 1/16"). Perhaps that doesn't matter when it's on and spinning. The brass nuts didn't screw on straight so I tried a normal hex nut but I almost needed a wrench to tighten it enough so the wood wouldn't slip when the tool touched it. Maybe I just need to work on my sharpening skills. I know my tools are sharper coming off the grinder than they started but they may not be sharp. Is there a way to gauge sharpness (other than creating a need for a bandaid or stiches)? I've bought the correct size drill bits for every kit I've tried. After seeing Mudder's diagram I may have misinterpreted the meaning of "out of round". The problem I have is that the tube is in the position labelled "driled hole", i.e. The wood ends up thicker on one side of the tube. So on one side of the pen the wood and metal are flush and on the opposite side the wood extends higher than the metal causing a bump. There is a class on turning acrylic pens at the local Woodcraft in March that I'm going try to sign up for tomorrow. I took my lathe to Woodcrat today and the manager claimed it was fine (and maybe it is, I don't really have anything else to compare it to). He tighented the nut on the bottom of the tailstock and things seemed ok. The stock drive and live centers lined up reasonably well, they weren't exact I don't think, but it was hard for me to tell (the tip of the drive center is bent a little). I tried explaing to him that I don't use the stock centers and that a bigger issue was that the mandrel visibly bends when advancing the tailstock with the 60° center. He claimed that the bending was just the mandrel and center "finding center" and that it would not affect the outcome of turning the pen. While it's true they were "finding center" my understanding is they shouldn't be offset to begin with. I told him if they were lined up properly to begin with they would already be centerd. His reply was that he's turned many pens with the mandrel bowing like that and they've been fine. He asked another gentleman (not sure if he was an employee as well or not) about turning pens like that and he concurred it wasn't an issue. When using a new stock live center (which he gave me free, a nice gesture I thought) it did not bow the mandrel when the tailstock was advanced. The 60° center still does bow the mandrel, but not as much. According to him all the pens turned in their classes are made with the stock live center. I'm under the impression the stock live center is the wrong type (hence I bought a 60° one, it's from PSI and it seems ok to me) and tried telling him that.

The manager also removed a bent washer from between the headstock and the hand wheel, which seems to have removed most of the wobble. It doesn't (and I'm not totally sure it ever did) seem to be wobbling the threaded portion of the spindle. However before when turning a pen mandrel in the collet chuck by hand I could see a wobble at the end of the mandrel, now with the same mandrel (which I thought I had bent) the wobble appears to be gone. I told him I was willing to give my lathe one more try. Now I just have to order another cutter head for my pen mill. [] I should search the site for the person who sharpens them and see if he still offers the service.

I see this got kind of long as well. It illustrates nicely though the problem with trying to describe and solve issues at a distance with words as a number of people have pointed out.

Thank you all again for the great response to my plea for help.

Mike

As a side note (one I think is kind of funny) after five years of living in Albany, NY I just found out a couple of months ago that there is a HF store 3.5 miles from where I work.[]

 

[ograywolf]

Interesting. After about 130 pens, I started cutting ovals too. At first, I thought it was the drill size for the the Jr. Gents. One of the drills seemed to be making really big holes. Then, I put a dial indicator on everything and found a bent mandrel. So I bought another one from CSA. Next pen was oval. Checked the new mandrel. Sucker was threaded off-center into the MT. I cut the 3/4" thread fitting off the old PSI mandrel, stuck the rod in a drill chuck, and turned round pens again. CSA is sending me another new mandrel as we speak. Great service there, I must say. Challenges do come in threes sometimes, or fours or sixes...

 

[opfoto]

Mike...

I just emailed you. We are in the same area. Try not to sweat the HF thing. They opened not too long ago. Central Ave, just below the Intersection of Rtes 155 & 5 on the left heading West on 5. Hope this helps. Marc