Anyone using these??

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I do not, but I can send you some TBC bushings that fit inside the mandrel bushings...although I find the mandrel bushings very often need to be de-burred or cleaned out when new. If you want a pair, just pm your address and I will mail. I find it easier just to use he mandrel bushing directly on centers..about 3/4 through the turning, I give each bushings a 1/4 turn in opposite directions.
 
TonyL said:
I do not, but I can send you some TBC bushings that fit inside the mandrel bushings...although I find the mandrel bushings very often need to be de-burred or cleaned out when new. If you want a pair, just pm your address and I will mail. I find it easier just to use he mandrel bushing directly on centers..about 3/4 through the turning, I give each bushings a 1/4 turn in opposite directions.
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Tony not me. I have some 60 degree bushings for some of my popular kits but never used them. I have no problem using a mandrel. Been using the same one for 12 years now. I brought it up because I saw this on facebook and thought it maybe something the newbies may want to try because of all the questions about turning between centers. I am good Tony, Thanks.
 
TonyL said:
I do not, but I can send you some TBC bushings that fit inside the mandrel bushings...although I find the mandrel bushings very often need to be de-burred or cleaned out when new. If you want a pair, just pm your address and I will mail. I find it easier just to use he mandrel bushing directly on centers..about 3/4 through the turning, I give each bushings a 1/4 turn in opposite directions.
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Tony, I'll take you up on your offer if it is still out there; I'm pm my address.
DrD
 
Weird timing... I just used them for the first time yesterday. I have traditionally used a Berea mandrel and never really had any issues. A year or so ago, I experimented with some TBC Sierra bushings that had 60 degree ends for the centers, and had some off center issues, so went back to the mandrel. Last week, for kicks I measured the runout on my Berea mandrel and was kinda shocked at how wobbly it was, so thought I'd give these a go.

I like them, after one turning.
 
I have them. They are OK but I prefer the TBC bushings as they are made from better steel and don't face the resizing issue nearly as quickly as regular bushings. I only use them when I do not have TBC bushings for the pen I am working on and can't put my hands on Brian Nikitas' TBC adapters.
 
I don't have many pairs to give a way for free. There are suppliers that sell them. They are not expensive.
 
I use them and have been pleased with the results. On another thread, I just now talked about them. The only problem I have with them is that there is less room to fit my vacuum platform in, so it can be a bit messier.
 
For years I used a similar homemade system to turn duck call barrels until I found expanding mandrels. I have also made a similar system for turning pens about 5 years ago. Basically it was a short piece of mandrel in a 2MT ER32 collet chuck and a homemade live center. It doesn't account for sloppily made bushings, so I think "properly" made TBC bushings are a better option.
 
I have a set that I've had for a while but have not used them yet. Of course, haven't done a lot of turning lately either.
 
I have been using one for over a year now. I love it. I used to wind up bending the mandrels and having to replace them. I have been using the one I use without any issues. The only real draw back is that you can only turn one blank at a time. I have found, however, that if you think ahead, you can turn each one and finish them in almost the same amount of time that it takes to do them together. For me this is not an issue because the majority of what I turn is single tube pen kits.
 
I have a set and I use them whenever I'm turning only one single tube pen. For single tube pens I turn a lot of, I have more than one set of bushings and I will turn 2 at a time on my mandrel. I have never tried true TBC yet. These work well for me. My only complain is that the rods that hold the bushings are a little short. I'd like to have them long enough for me to put a spacer outside the bushings to put my tools another 3/8" from the tapers. That's just me, tho. They work great.
 
I have the PSI TBC mandrel system. I do not use it often. I use it mostly when I teach or demo the various methods to turn between centers. I have no complaints about mine but others hf ake not had good results.

I have never understood how so many penturners seem to end up with "bent" mandrels. I do have some thoughts on the OOR problems. Another day.

When I do add to my TBC bushing collection they will only be purchased from Brian Nikitas and never from those who sell the ones made in China.

Do a good turn daily!
Don
 
For grins I measured the runout related to this tonight on my old beater Harbor Freight lathe...

I have less than 0.001 inside my MT2, which is what you'd expect, though it is a cheap lathe. With my old, well worn Berea mandrel I was 0.010" at the headstock end of the mandrels rod, and with the new TBC mandrel being discussed here, I was 0.003" runout at the same point as the Berea. Aside from doing what I always do when I'm turning (clear debris, insert into taper square and tight with a little twist), I didn't try to do any tuning to improve the readings.
 
its_virgil said:
I have the PSI TBC mandrel system. I do not use it often. I use it mostly when I teach or demo the various methods to turn between centers. I have no complaints about mine but others hf ake not had good results.

I have never understood how so many penturners seem to end up with "bent" mandrels. I do have some thoughts on the OOR problems. Another day.

When I do add to my TBC bushing collection they will only be purchased from Brian Nikitas and never from those who sell the ones made in China.

Do a good turn daily!
Don
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Don I agree with your statement about bent mandrels. Like I have mentioned here I still use the same one I have been for 12 years and still works fine. I turn one blank at a time because if you break it down that is all you can do even if you mount both on the mandrel. Yes it takes an extra minute to change blanks but again I am repeating myself, most problems arise from human error and the rush they are always in. Most of the time it is not the tools but the operators of those tools that are the cause of problems. I finish with BTC but always turn with bushings.

You mention OOR and there are tricks for many problems that arise but for the OOR there are a few factors. Yes bushings can be a problem, not squaring the ends is another, bent mandrel another and I am sure there is more. But a little trick that hardly gets mentioned here is to rotate the blank ever so slightly as you turn the blank down close to finished size. This will spread the error out over the entire blank more evenly.
 
I've been using these for a while and like them a lot. I've used the 60 degree ones too, but found them not as effective.
 
jttheclockman said:
https://www.pennstateind.com/store/PKMBCM2.html

If so how are they working and could these be an answer for combining turning between centers and using a mandrel?? Maybe something for those starting out to try and not too expensive.
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Thanks for posting this...just bought a set for the heck of it. I have no issue with a mandrel & saver. Can turn 2-3 blanks at one time but will see where these fit in.
 
WriteON said:
Thanks for posting this...just bought a set for the heck of it. I have no issue with a mandrel & saver. Can turn 2-3 blanks at one time but will see where these fit in.
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Those are the key words see where they fit in. Not for everyone but just throwing options out there and thought the idea was good. How well they work I will never know because I doubt I ever buy them.

Thanks everyone for commenting and putting a live person to them and their use.
 
jttheclockman said:
But a little trick that hardly gets mentioned here is to rotate the blank ever so slightly as you turn the blank down close to finished size. This will spread the error out over the entire blank more evenly.
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I'm just starting to do this.... definitely makes a noticeable difference.
 
TonyL said:
One can buy TBC bushings for a slim line and use those with non-TBC bushings.
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I tried that Tony but found to much slop. The regular kit bushings don't seem to fit like the TBC bushings do and then there is also some slop between the slim TBC bushing and the regular bushing. What I have done is drilled the back of some of my regular bushings to 60 degrees and it seemed to work ok.
 
Rick_G said:
I tried that Tony but found to much slop. The regular kit bushings don't seem to fit like the TBC bushings do and then there is also some slop between the slim TBC bushing and the regular bushing. What I have done is drilled the back of some of my regular bushings to 60 degrees and it seemed to work ok.
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if i don't have a tbc bushing, i simply place the mandrel bushing between the 60 degree centers - about 1/2 to 3/4s thru turning i rotate the bushings a 1/4 turn in the opposite directions. for the kits i make regularly i have an aircraft parts machinist make tbc bushings for me. I agree with you.
 
jttheclockman said:
Don I agree with your statement about bent mandrels. Like I have mentioned here I still use the same one I have been for 12 years and still works fine. I turn one blank at a time because if you break it down that is all you can do even if you mount both on the mandrel. Yes it takes an extra minute to change blanks but again I am repeating myself, most problems arise from human error and the rush they are always in. Most of the time it is not the tools but the operators of those tools that are the cause of problems. I finish with BTC but always turn with bushings.

You mention OOR and there are tricks for many problems that arise but for the OOR there are a few factors. Yes bushings can be a problem, not squaring the ends is another, bent mandrel another and I am sure there is more. But a little trick that hardly gets mentioned here is to rotate the blank ever so slightly as you turn the blank down close to finished size. This will spread the error out over the entire blank more evenly.
Click to expand...
I agree as well. Though I don't turn much lately, been using the same mandrel for close to 20 years! Wrote a deal on OOR and some of my thoughts years ago as well, but.........
 
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