Turning without mandrel

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stevebuk

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Mar 3, 2008
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169
Location
nottm, United Kingdom.
hello
I have noticed that several pen makers say they turn the blanks between centres without the mandrels.
Is the brass tube inside during this period, and if so what means of grip do you use to turn the blank.
Hmm curious...
 
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Haven't tried it yet but my understanding is you use a live center and dead center and bushings. I think the brass tube is in. Some of the others can probably tell you better since they have done it. There have been quite a few discussions in the last 2 weeks on this topic. I'm hoping to try it myself once I get some money for the centers and bushings. I hope this helps.
 
Yes, the tubes are in, the 60 degree dead center turns the bushings (if you use them) that support the pen tube.

OR, the dead center will turn the pen tubes (and material), just controlled by tailstock pressure.

All of this happens IF your tools are sharp and you are CUTTING your material off. IF you have dull tools and you beat your blanks to death, this is a much less effective method.
 
This is the only way I do it now. And I use the standard bushings for most of my kits. And I purchased a set of slimline and streamline bushings so I can do them between centers too. I got fed up with out of round pens, even when I get top quality mandrel rods. I still use my rods for sanding and finishing. Makes things much quicker.

Only things you need to buy is a dead center and a live center and you can use standard bushings for most pens except 7mm stuff, like slims and streamlines.
 
Steve turning between centres is ideal if you are experiencing oval pen barrels, I use a dead centre in my headstock and a live centre in my tailstock.

Special bushings for all kit styles can be bought from John Goodin (johnnycnc), I bought Slimline, Comfort and European bushings from him, but for other kits I use the original bushings meant for a mandrel.

There are more penturners going down this road, and it is relatively inexpensive for a dead centre.
http://cgi.ebay.co.uk/2-MORSE-TAPER...ZWD1VQQ_trksidZp1638.m118.l1247QQcmdZViewItem
 
I bought a dead center to try last week and I'm a convert. I paid an extra $4 for one with a hardened tip. If the tip isn't hardened I don't think it will take long to develop wear marks if the bushing slips on it a few times. JMHO
Yes, the tubes are in and I use the standard bushings.
 
thanks guys, i just bought one from him mark. Do i understand you correctly, i need to use special bushings for the kits, and if so is johnnycnc in this forum?
thank you
 
Steve,you do not have to use special bushings,
except maybe for 7mm tubed kits.
You can use the factory bushings to try between centers out,
as long as the bushings have a "step" in the diameter.
Some folks are satisfied with their results using this method.
I wasn't and that's why I make these:
http://xrl.us/BushingsAlaCarte
I have some pictures in a CLOSED,OUTDATED ad,here;
http://www.penturners.org/forum/topic.asp?TOPIC_ID=29489

Feel free to ask any other questions you may have.:)

Originally posted by stevebuk

thanks guys, i just bought one from him mark. Do i understand you correctly, i need to use special bushings for the kits, and if so is johnnycnc in this forum?
thank you
Click to expand...
 
Just to elaborate a little bit. John's bushings have two major advantages compared to the stock bushings.

A) They have a true 60-degree hole the centers fit into. This reduces wear, improves mechanical grip and it is perfectly in line with the tube step as well as the bushing OD.

B) The diameter of the tube is sized properly to the tube. Many bushings do not have all that great of a fit between the tube and the bushing. You should be able to take one of John's bushings and turn the blank upside down without the bushing falling out.

This method of turning also has a few hidden advantages. You can remove a blank from the lathe in seconds to measure it because you just need to loosen the tailstock a little, not slide it out of the way. I find it much eaiser to measure a blank in hand than while on the lathe.
Then you can remove the bushings for your final sanding. This not only makes your bushings last almost forever, you do not drag metal into the wood from the bushings. I size my blanks undersize to allow the CA film thickness to build back up to the proper dimension of the hardware. I measure and log on a post-it note every pen and build to that exact kit.
When you apply a CA finish, a major problem is stuck bushings & chipped CA finishes. With the mandreless method you can apply your finish without bushings which will end forever bushings stuck to a pen.
 
This one just came off the bushings from Johnny.
Absolutely no ridge between the nib and the wood.
The bushings are worth every penny, thanks to Johnny and all his salesmen. I am still having a problem with the ridge but it must be the alignment of the head and tail stock so I make sure that when I turn the nib end it is at the head stock. That has cured my headache. Anyone want to buy a bunch of used, bent, worn out mandrels[:eek:)][:eek:)][:eek:)]
2008310123947_S7300275.jpg
 
many thanks for the info, i really want to try between centre cutting, could i just ask, what is delrin, your spreadsheet says it, and man, how many sets have you got, i would need another mortgage.:D
 
Delrin,as noted,is a plastic that finishes won't stick to nearly
as brutally as they will to a steel bushing.
It's only a few sets there,sorry I can't get them all![:p]

Originally posted by stevebuk

many thanks for the info, i really want to try between centre cutting, could i just ask, what is delrin, your spreadsheet says it, and man, how many sets have you got, i would need another mortgage.:D
Click to expand...
 
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