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Discussion Starter #1
I enjoy making pens, so I do it often. I hate the bushings though. They aren't as round as I'd like them to be and they don't fit very well on the mandril or in the brass tubes. All of my pens end up slightly out of round, no matter what I do. I've heard of some 60 degree bushings from Penturner's Products, but he never seems to have bushings I want. I've looked for others selling similar bushings, but can't seem to find anyone with them. My internet skills aren't as good as they used to be.

As always, I have questions. You know you expected it. Is there someone else selling 60 degree bushings that are high enough quality to give good results? Would it be easier to just get a 60 degree drill bit and turn my mandril bushings into 60 degree bushings? Is there a way to just forget the bushings all together and turn between centers without messing up the tubes? Every time I've tried it, I end up flaring the tube ends which can't be good. Do I just stink at turning pens and should stop now before I mess up another one?
 

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Yes, you can turn between centers without bushings. Thats my preferred way as it allows you to be much more precise and we know thats key when working with something as small as a pen.

I use my mandrel and bushing to get somewhat close. Doing that allows me to vision what the pen will look like. This is important on double barrel pens with any shape other than a flat profile. When Im close, I ditch the mandrel and bushings and finish turn the barrels individually between centers. I just use a 60° dead center and a 60° live center. You only need enough pressure to hold the blank and spin it without it free spinning. A little flaring isnt a bad thing as it helps to start your componants when you press it all together. It dosnt take much flaring to start cracking your blank though so you definately have to be careful with your pressure. Youll have to use calipers to measure your componants and turn them to those dimensions. The results are a better looking pen than dosnt have a noticeable edge where the componant meets the blank and your blanks will always be round. You also sand and finish between centers and you dont have to worry about stuck bushings.

FWIW, out of round can be more than bushings. It could be a bent mandrel, too much pressure on your mandrel or a lathe that needs some adjustment.
 

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Discussion Starter #3
I never thought about a bent mandrel, but it makes sense. Even if it is bent, finishing the pen without bushings would make it true again. I have a live and dead 60° center. I'll have to give it a try again, but with less pressure so I don't mess up the ends again.
 

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I agree with Bassblaster. If you're concerned about maybe over-tightening, here is another source for "turn between center" bushings -- Lazerlinez

I haven't checked this out, but the IAP "Birthday Bash" is going on at the moment, last year at this time Lazerlinez was offering discount and/or free shipping to IAP members. (It's free, you just register on the site.)
 

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A lot of pen turners use a holllow live center so that there is no pressure on the mandrel. Also, most live centers will not work well with pen mandrels and even some with a 60° tip aren't precise enough. There are some higher quality metal lathe live centers that work better than the cheap ones made for woodturning. If you have a granite reference flat surface or even a piece of thick tempered plate glass, yoou can check a mandrel for straightness -- in all likelihood yours isn't straight. I haven't seen any bushings that weren't round or concentric, but I suppose that there are some cheap ones that don't run true. Don't skimp on cost by not getting quality bushings. When using a mandrel, the tailstock center has to align absolutely perfectly with the spindle axis. By turning between centers without a mandrel, slight misalignment is not a problem.
 

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point to point

Have you assured that your centers are aligned. Even a little misalignment can result in a wobble resulting asymmetry. (voice of experience) I finally figured out I had some minimal deposits on the bed, after cleaning all better. just saying'
 

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Have you assured that your centers are aligned. Even a little misalignment can result in a wobble resulting asymmetry. (voice of experience) I finally figured out I had some minimal deposits on the bed, after cleaning all better. just saying'
And, one other thought, if you use a mandrel, run it at low speed without anything installed on it and just a bit short of making contact with the live center. Does the end run perfectly true or is it making a coning motion at the end. If it is coning then the mandrel is bent. This is a separate issue from the one mention by jtd, but the end result is similar if it is forced into a cone center.

I have had some success in straightening a bent mandrel bending it in the opposite direction. It usually takes several iterations to get it running true, but it works reasonably well.
 

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Discussion Starter #9
Have you assured that your centers are aligned. Even a little misalignment can result in a wobble resulting asymmetry. (voice of experience) I finally figured out I had some minimal deposits on the bed, after cleaning all better. just saying'
I've run the lathe with a 60 degree center in both the headstock and tailstock. The points meet as perfectly as I can see. If they're misaligned, it's so minor that I don't think it could possibly have any effect.
And, one other thought, if you use a mandrel, run it at low speed without anything installed on it and just a bit short of making contact with the live center. Does the end run perfectly true or is it making a coning motion at the end. If it is coning then the mandrel is bent. This is a separate issue from the one mention by jtd, but the end result is similar if it is forced into a cone center.

I have had some success in straightening a bent mandrel bending it in the opposite direction. It usually takes several iterations to get it running true, but it works reasonably well.
I never thought about doing that. The weight of the mandrel cantilevered out wouldn't throw off it's ballance? I guess I assumed it would wobble without something keeping the tail end centered. I'll have to go check it out.
 

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i have one set of bushings that are out of round and have been since i got them
i thought it was my mandrel at first but realized it was the bushings
 

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If you have ever had a Morse taper spin the the spindle socket then there will be damage that must be repaired before any mandrel will run true. Look into the Morse taper socket using a flashlight to see if there is any galling rings -- you can also use a finger to feel for any galling. If there is any then the Morse taper on a mandrel will not seat true. A damaged socket can be repaired by using a Morse taper hand reamer (about $50) and then cleaned up and polished using a Spin-L-Mate tool ($70 + $50 for EP blades). If the damage is very light then you can probably get by with only a MT hand reamer. Also, if the socket is damaged then at least on of your spur drives or other MT drives is damaged as well. I don't know of any tool for repairing the surface so it is best to just toss the damaged drive and get a new one.
 

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Late addition, I'm browsing.... I had trouble with my powermatic last year, tried everything. After checking carefully I found that I had a build up under the headstock of a little sawdust and after cleaning it up with a scraper had perfect alignment again. The Whiteside pen mandrel is the best I've found.
 
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