# Turning without bushings?



## spnemo (Dec 9, 2010)

My wallstreet bushings are useless, so I guess it is time to learn another method.  I have a few questions:

1. What tools should I use to turn the tubes without using the bushings (calipers, digital calipers, micrometer)? 

2. Should I keep the bushings as a general reference (even though they are too small now)?

3. I already turn between centers for my pens, what else do I need to learn before atempting this method?

 Thanks for the help!


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## IPD_Mrs (Dec 9, 2010)

You should always have calipers that you can easily read.  Every kit will vary be thousandths.  My suggestion would be to try the bushings that JohnnyCNC makes.  We use bushings as a guideline only.  After we get them to the size we want all of our sanding and finishing is done between centers off of the bushings, or on delrin bushings.


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## DJS588 (Dec 9, 2010)

I agree with MLK, it would be good to have a pair of calipers. Then measure the diamaters of the mating surfaces of the various parts. Lock the calipers at the appropriate diamaters and turn your part with the bushings. When you get close to the undersized bushings you then use the calipers to check the size of that part of the blank. When the calipers are a little proud you can sand, etc.
Hope this helps.


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## spnemo (Dec 9, 2010)

I have a good pair of dial calipers that I can lock in place.  Would that be good enough or do I need the digital readout to know how many thousandths to add or take off?


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## ctubbs (Dec 9, 2010)

I find that knowing exactly how many thousandths to remove does not help all that much.  A go - no go gauge helps me more.  I can watch how far over the turning it goes and that gives me a good idea how much to cut.  If I were using a metal lathe where I could know exactly how much each cut was removing, then knowing how much needed to come off would make a difference, but on my lathe, my eye and hand are the only tool control I have, so I work by guess and seeing where the gauge runs tells me more than the exact number on the caliper.  YMMV and probably will.
Charles


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## BigguyZ (Dec 10, 2010)

I use the plastic digital caliper from Rockler that goes on sale for $10.  It doesn't mar the finish, and is accurate.  

I don't use any type of bushing ever, as that is just another chance to introduce runout.  Instead, I just turn on the centers.  Trick is to not tighten too much, as you can crack the material.


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## GoodTurns (Dec 10, 2010)

BigguyZ said:


> ... I just turn on the centers.  Trick is to not tighten too much, as you can crack the material.



or you can flare the tube ends, making a loose fit on the kit.  I use old bushings, just for support, not size and a caliper to check sizing.


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## jttheclockman (Dec 10, 2010)

I don't think anyone here ever gets all pens they turn exactly to the measurements they are looking for because if they do then they are machines and not humans. We all do the best we can. My process is to always measure the tip of the bushing that will touch the blank before mounting on my mandrel. You always seem to hit the bushing when we turn or sand so this may or may not take a few thousandths off over time. I then measure the kit parts because as said they too are not always exact. I use a digital caliper because being able to read numbers is a whole lot easier than trying to read the old style linier calipers. And using a fixed locked caliper leaves too much flexibility in both the angle you apply and the stretch in the ends. Those are good for spindle work, not a fan for pen turning. One thing is to always zero out the calipers before doing any measuring.  When you have 2 solid measurements you work to match them. If you are  a couple thousandths off one way or other don't sweat it but strive to do better next time. Of course it always easier to take more off than put more on. Good luck and that is my 2¢


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## okiebugg (Dec 10, 2010)

*Bushings*

I make my own with a wood lathe

Having started turning pens in the late 80's, I didn't have access to extra bushings without paying through the nose.

I found thick wall brass tubing at a bearing sales Co. cut it to length and mounted and firmed it up on a regular pen mandrel I use a carving skew with a small radius ground onto it. A small square carbide tool works well I learned later.
Eye protection is a must, as the brass tends to come off as dust particles

 Lowest RPM you can achieve. Tool rest right up against the brass and slightly below center helps minimize chatter. A very light touch with the skew point is mandatory. The actual bushings can be turned to within a few thousandths using your tool. I cannot emphasize enough a light touch for safety. When you get close to the finished diameters with your DIGITAL calipers. You can actually set most calipers to show how much you need to remove to get to your actual diameter.

When you get close to the correct diameter, I use 1 inch wide by 400 grit sandpaper to finish to diameter. 

After you learn through trial and error to make your own, you can sell them. Pride in workmanship is without parallel


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