The Dead Center

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workinforwood

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Yea, I've read the pdf several times. I've read all the pro's and con's about it. I'm seriously considering it, even bought myself a nice set of digital calipers. The dead center I'm guessing goes in the drive of the lathe and then what goes on the other end, a special live center?

What really turns me off about it is spinning one blank at a time, that's 2 days to make one pen, or I get another lathe? I have to wonder, why can't I make 2 blanks, or even more than 2 at a time? Why not a double sided dead center with lets say a groove in the center that a steady rest can support which would be placed in between 2 blanks and/or add more for 3 blanks...that's probably as much as fits on my jet mini, but ya'll can probably imagine what I'm thinking. I'm sure a Johnny cnc or someone else can rig something like that to happen. It takes time to make a proper pen, and most of that time is in the finish. Time is also money, as many of us know as well.

So I don't know what I'm talking about and you guys/gals can fill me in on that part, and perhaps I'm on to something at the same time?
 
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leehljp

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I think what you are talking about has been done or tried. I think Lee Thomas made (or is thinking of making) a center bushing that will allow two blanks to be butted together.

You are right that time is money but when put into "nice pen" context - quality often suffers when time limits are applied. Some people have it down to a science and can turn a great looking pen with a nice finish in a short time. I can also, once in a great while, but most of the time, I have to work at it.
 

Firefyter-emt

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I do not suggest turning with the "coupler bushing" myself, but what could be made is a set of Derlin bushings that are cone shaped and one double cone. If you had a thin taper you could hold both blanks in the lathe for CA application. What I have found is that it is well worth the extra time, but I am not a "production guy" I just want them perfect and I am willing to take the extra time myself. You are right about the dead center, it goes in the headstock and just your normal live center is left in the tailstock. You could also make a pair of cone derlin bushings to apply CA on your mandrel.

I find that one the CA is applied and set up for a few minutes I can remove the blank, place on my peg board and then start in on the next pen. I can apply the straight CA to the pen in one day. If I had to push it, I can turn, sand and apply CA on one day and sand it out, polish it and press it the very next day. (add one more day to sit and degass the CA before it get's put togather.)
 

workinforwood

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right, I'm not trying to make 50 a day, but I do like to spin 2 blanks at a time. My live center is so small though. It's just whatever the one is that came with the jet mini. It's like a cup with a point in the center and the point doesn't really stick past the cup and isn't large in diameter. If I had a dead center on the drive side, the live side would slop around.

The double sided cone thingy in the center is exactly what I was thinking too. But if both ends aren't perfectly square in the tubes, the blanks would wobble, or would a bit of pressure from the tail stock automatically push everything straight, square, level. ? Perhaps the dead center, center cones and live center needs a small rod connecting through them to line them all up.
 

johnnycnc

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Jeff,I tried the center bushing thing for myself.
It is a bear to get true,a lot more trouble to machine
and make right.I don't even use the center double-ender myself.
To be honest,I threw away the ones I made!I expect as close
to perfect as possible and they did not work worth a crap for me.[:p]
the more mechanical joints you have,the more opportunities for runout.
Also the length added by two blanks is a stretch for the relative
length to diameter ratio for best stiffness.The single blank is more rigid
between centers,than two on a mandrel,so I gain time there.
Maybe finish on a mandrel after turning between centers??
You really ought to try a regular live center,you will be surprised
at the difference,especially if your original is chewed up or worn.
And,reading your last post,about a rod connecting all the centers and such,
just leads you right back to a mandrel by a different name..
I think Lee's idea sounds okay,sure wouldn't hurt to give it a spin.[:)]
 

Rifleman1776

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Jeff, the live center you have is called a 'cup' type. It is not suitable for what we do. It is for turning bowls, larger spindles and such. Do invest $5.00 to $10.00 in a 60 degree coned live center. It will be a valuable tool for many uses beside pens.
 

workinforwood

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Thanks guys. I had no idea. I know the tip on the live center is warn round from spinning a mandrel. Not all my thoughts and idea's are genious. Perhaps I'll have to get John to make me one of those live centers some time.
 

Randy_

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This is what you need:
60° Live Center

Having Johnny make you one would probably cost you $100.

Some Woodcraft stores sell replacement tips for the JET cup center. They are less than 2 bucks. Don't bother calling JET, they charge about the same price for the point; but wanted to add their standard shipping fee of $21.95. After a long discussion, they came down to $10.95. Still way too much. I popped the point out of the cup center and restored it with a file.
 

johnnycnc

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Jeff,I'm just shortly in from work and will be
sending you a pm.I have something I planned on sending you anyway.
Later.
WOW,Randy I could use you for a sales rep.
100 bucks.My goodness!
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workinforwood

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I was wondering about how to go about replacing it. I looked at live centers at the woodcraft store and they are outrageous in prices and how would I know what one I want? John was telling me how to knock it out, I just haven't done it yet because then I'd have nothing. [:D]
 
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