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View Full Version : A step up in pen mandrels



Roger Chandler
03-19-2012, 3:04 PM
Hi folks,

I had the pen mandrel I purchased a few months ago from WC cause me problems over the last few times I used it, then it stripped out the threads where the brass nut went on.

I purchased a new mandrel from PSI, and got it in today .............it is a cut above what I had for sure....a better design, has a centering collet out of steel and is adjustable for length in case you want to do different styles of pens with it, and is a better quality morse taper #2 than the one I got from WC.

Just thought I would pass on the info on this as I know there are many pen turners who read this forum. I am impressed with the quality of this Maxi Mandrel from PSI.....it came with extra bushings in case you lose one, and they throw in a new 7 mm drill bit at no charge! :D .....I also like the live center that will allow the mandrel rod to fit inside and you do not need the brass nut..........a great system!

http://www.pennstateind.com/store/PKM-FLC.html

http://www.pennstateind.com/store/PKMSTS2.html

Hope some folks find this helpful........:)

mickey cassiba
03-19-2012, 4:03 PM
Roger, thanks for the review. I've been contemplating a move up from my old mandrel, but haven't heard any feedback about the new(er) PSI unit.

Billy Tallant
03-19-2012, 7:11 PM
Roger, thanks for the review. I think the best thing you mentioned was the pen saving mandrel. I've been using one for the last year or so. It makes life so much easier being able to just slide that tailstock up against the bushings & work from there.

Bernie Weishapl
03-19-2012, 7:53 PM
I have the same setup Roger and love it. Really works nicely.

Jim Burr
03-19-2012, 8:00 PM
Pen savers are ok for the "now-and-then" pen...I gave mine to my BIL for just that reason. BTC bushings cost no more than a couple replacement mandrels and really make a pen that is a step above. I bring this up since a lot of pens made by several members here are for gifts. Mandrels are consistently out of round, they simply have no choice because of their construction. Give BTC bushings some thought.

Sid Matheny
03-19-2012, 8:01 PM
I have not been making many pens lately but have used that mandrel for several years and a home made mandrel saver. I need to order one of their mandrel savers with my next order. I'm sure it works better than my home made one.

Sid

Roger Chandler
03-19-2012, 9:04 PM
I have the same setup Roger and love it. Really works nicely.

I like the mandrel design Bernie ..........that collet centers the rod in the morse taper and gives concentricity to the pen........ with the one I had from WC, the rod developed wobble after a few pens, and that was without too much pressure from the tailstock...........I was careful not to put much pressure at all on the rod, so as not to put a bend in it, but I guess like most things made in China, the quality is lacking to some degree...........

The package this maxi mandrel came in said it is made in Taiwan and from what I hear the factories in Taiwan are rated with ISO 9001 and better...........that may account for the difference in the quality of this.........even the packaging was very nice and a protective case came with it...........not bad at all!

Roger Chandler
03-19-2012, 9:07 PM
I think the best thing you mentioned was the pen saving mandrel.

Billy,

That is a really nice way to do a live center..........it just slides over the rod, and you have the pressure from the tailstock putting friction and you don't have to worry about the threads on the end getting messed up. I agree with you about it.

James Combs
03-19-2012, 9:17 PM
Pen savers are ok for the "now-and-then" pen...I gave mine to my BIL for just that reason. BTC bushings cost no more than a couple replacement mandrels and really make a pen that is a step above. I bring this up since a lot of pens made by several members here are for gifts. Mandrels are consistently out of round, they simply have no choice because of their construction. Give BTC bushings some thought.

What Jim said. If you want to really up your pen quality BTC bushings is the way to go. I have been making my own BTC bushings and double checking finish diameter of the pen part with calipers against the kit parts. There are some detectable differences between different brands of the same style and the size of the parts particularly the center band. Another advantage to turning BTC is that if you get a catch, usually the only thing that happens is your blank stops turning instead of shattering or chipping out.

If you want to try BTC without investing in new bushings try chucking up your currant bushings between a dead center(not a spur) and a live tail stock center, even this will improve your pen part due to not having a mandrel flexing on you. You wont be able to take very much of a cut do to the lack of friction between the standard bushing and the dead center. You can improve the friction though by putting a little bit of chamfer on the inside of the bushing that rides on the dead center. A small chamfer should not effect the use of the bushing if you go back to a madrel. Try it this way once and see the improvement in the quality of your pen barrel. However, as has been said for other different techniques YMMV.

I have not purchased BTC bushings so I am not 100% sure how that are made inside. However, I make my BTC bushings with a 1/4" flat chamfer built into the bushing to act as a friction clutch.

Roger Chandler
03-19-2012, 9:26 PM
JD..........I am not familiar with BTC bushings...........a couple of pics would really be helpful and maybe you could illustrate somehow what you were mentioning.........not having a mental picture of what you are speaking of, I am a bit lost with your description........

...........which if you show a couple of pics, I am sure will make total sense...........thanks for the reply from yourself and from Jim as well.

James Combs
03-19-2012, 9:33 PM
Roger I just found this YouTube video (http://www.youtube.com/watch?v=p6wTnychR1U) that shows it better then I could photograph it. Let me know what you think.

Edit: and a lot better then I can explain it. lol

Roger Chandler
03-19-2012, 9:51 PM
Roger I just found this YouTube video (http://www.youtube.com/watch?v=p6wTnychR1U) that shows it better then I could photograph it. Let me know what you think.

Edit: and a lot better then I can explain it. lol

Thanks JD.........that was very informative........if someone had said bushing that were made to go into the ends to the tubes and placed between centers to turn it, then I might have gotten a fairly good mental image.............

Where does one purchase BTC bushings...........I am not a machinist, but this might be an option at some point..........that being said, the Maxi mandrel and the live center that the mandrel fits into do give a very concentric [true to round] pen blank.

Jim Burr
03-19-2012, 10:47 PM
Penturnersproducts dot com. Tell John I sent you. I would suggest picking a style, Sierra, Aero, Jr Gent, so on...get the bushings and have at it. First do what JD suggested and use the bearings you have between a 60 degree dead center and a 60 live center...pics on hand of all scenarios. The problem with that (and I still do some of these) is that bushings for mandrels can be off center by hundreds of an inch. When you have a pen wall that's a 64th to the tube...there is no messing around! I still have a few that are like that and I use them on occasion. Let me know if you want pic's of the "fun tools"! I swear...and I don't...it's worse than buying bowl gouges:mad::mad::mad:

jerry downey
03-20-2012, 12:22 AM
Has any tried this? It holds the pen in tension rather than compression.
http://www.penmandrel.com/

Thanks Jerry

Lupe Duncan
03-20-2012, 1:42 AM
Much of the slop that comes with the mandrel setup is due to the bushings used to turn the blanks. I got started with the two 60deg centers and GENTLY placed a blank between them. You cant crank down on the tail-stock or you will flare the brass and crack the blank as it gets thinner.
Makes a big difference if you dont like the OOR associated with the bushings. I went mandrel-less and bushings-less for several years before I got a set from John At PTP.
The only problem I have encountered with the no bushing scenario is when I have reverse painted the blank. I seem to get a small seperation between the blank and paint. I've seen "Air pockets" under the blank.