A Little Help Please!

[fishman]

Hello,

Really glad I found this site as it's a huge resource. I just started turning pens about a week ago, and for the most part everything is going pretty well except a few parts I'm struggling with a bit. Hope somebody has some tips on what I can do to get more consistent results and not rely on "luck."

1. After I apply the CA finish (I use GluBoost) and it's time to remove the pen from the mandrel I often get a little chip on 1-2 edges of the pen when separating the pen from the bushings. I've tried regular metal bushings and those white cone ones made for CA finishes. I started taking an exacto knife and scoring it before separating the bushing, but results are hit or miss. Is there anything I should be doing different? I try to not get the glue on the bushing to avoid this problem, easier said than done though!

2. I often struggle with getting the blanks the perfect size to match the hardware and once assembled for example where the blank meets the tip there is a little ridge and it's not seamless. I've tried all sorts of techniques, and I just can't seem to consistently get the results I want. I know that the CA finish adds some thickness to it. Any tips on getting consistent results for this? In the end it usually ends up either just under or over the pen tip and cap and I'm left with a little hairline ridge you can feel.

3. How many pens do you typically turn from one set of bearings?

Thank you for any help!

 

[Fred Bruche]

1. Have you tried with sandpaper on a flat surface, holding the barrel vertical?
2. A vernier caliper is your best friend.

 

[magpens]

I agree with Fred ... get a vernier caliper (metal, not plastic) with digital readout. . And make the measurement after taking the blank off the lathe.

It takes a bit of time to make the measurements, but you get good at it after a while.

Also, learn to do your turning without bushings ... using the TBC technique (Turning-Between-Centers) ... and make frequent measurements

Even if you continue to use bushings for the turning, you should remove the bushings before applying CA and do that part by TBC.
That will avoid getting the bushings CA'd to your blank which inevitably leads to the problems you mentioned.

In order to do TBC you will need a 60-degree conical dead center in your headstock and a 60-degree conical live center in your tailstock.
Most people use the 60-degree centers because they are commonly available.
But if you have the tooling and ability to make your own, than a shallower angle, of say 30 to 40 degrees is better.
I have made my own using a plastic-like material called Delrin, to which CA does not stick quite so much.
You mentioned the white cones. . If you can buy some of that white material, then make your own cones out of it. . It's better than Delrin.

Getting an "exact" matching fit/size between the blank and your pen hardware is very tricky and takes lots of practice.
Some recommend that you turn the ends of your blank so that they are a tiny bit undersize (say 1 or 1.5 thousands of an inch) and allow the CA to then bring the ends up to the proper size after sanding. . Obviously, that is an even trickier business, but it can be learned.
After 10 years of making pens, I don't know of any easy sure way to do this, but lots of practice does help to get you there ... some of the time !

Using a caliper does help with all of these sizing issues. . Bushings will never get you there, in my experience.

Oh, and as Fred said, sanding the blank ends with the sandpaper on a flat table surface is another very useful technique to learn.
It helps to bring the blank ends back to square after you have done your CA'ing, which always leaves the ends a bit "off".

 

[fishman]

Thanks for the input. I should have mentioned I do have a digital caliper like you both mentioned. I turned a pen with it last night, but I didn't take the blank off the lathe to measure it. That sounds much easier and more accurate though. So I will give that a try next time.

The next pen I'll turn a little bit smaller than the pen hardware/bushing and use the CA to bring it up a bit. If I take it off the lathe, use my calipers and see it's still to low I will add a few more coats of medium CA to bring it up. While this seems more time consuming, if it gets me the results I want I have no problem with it. I feel like with a lot of practice this will get easier.

Oh, and the first thing I tried was sanding the ends on a flat piece of sandpaper and that caused a chip. However it was most likely because there was too much excess glue. So I will use the knife to carefully trim away the excess and then sand the ends. I guess all of this just takes some more practice!

 

[howsitwork]

I think the white plastic you're referring to is HDPE ( high density poly ethylene ) . Its available as sheet and rod forms and can be easily turned on a wood turning lathe but DONT try to sand it as it just fluffs up.

Epoxy, CA etc just wipe off it. I made an insertion tool for the tubes out of it by turning a long taper from a piece of flat sheet I had.

 

[magpens]

When you are sanding the blank ends to get the little bit of CA off, use a medium grit not a coarse grit ... takes a few seconds longer but is more gentle .... I recommend 240 grit or 320 grit. . Hopefully you have only a tiny bit of CA to take off and it usually takes only 10 to 20 circular strokes on the sandpaper ... and you don't have to press very hard ... keep the pressure firm but fairly light and rotate the blank in your fingers every 5 or so circles to make the removal process more uniform,

 

[leehljp]

Another vote for Calipers for measuring. HF often has their $18-$19 calipers on sale for $9-$10. DON'T get the plastic ones, get the metal ones.

Measure the center band, the clip end, the nib end and write the measurements down and turn to that size, not the bushing size. I overturn to about .005 or so and build up CA to over just a tad and sand/turn to perfect size.

The chips caused by separating the bushings from the blank is what pushed me to try turning between centers. This happened repeatedly on oily ebony and was frustrating.

 

[Dale Allen]

To some degree your technique for applying CA will determine the thickness and also how many coats you put on will vary the thickness.
Do a test blank and measure it before and after applying the CA. That will give you an approximation of what thickness to allow for.

 

[Woodchipper]

See? Lots of advice and don't be afraid to ask questions.

 

[BruceA]

Consider using a pen kit that has a mating edge between the barrel and the nib (pen tip) that is PARALLEL, and not angled, like a Sierra style kit. It's going to be easier as you start learning to match the diameter of the barrels to the nib If you're trying to mate to something that does NOT have a 90 degree angle edge, it's challenging no matter how many times you've done it.

 

[jttheclockman]

Each and every kit even though the same may have different amounts of plating so that is why you measure the kit parts before hand and mark them down. Then measure the bushings and you will now have a feel of where you need to be when turning with bushings. I have used the same bushings for a very long time and in fact I purposely turn the down below actual measurements. Now I only use the bushings to hold the blank till I get close. Then use calipers to hone in. It does take a little practice if using woods and doing a top coat finish of any kind. With acrylics no need to worry about finish. just turn and polish to part measurements.

 

[howsitwork]

One thing worth mentioning with vernier callipers is to round over the sharp tips of the external jaws . Just the tips for about 1/32 " or so they don't catch if you measure when running ( which naturally none of us ever do ).

 

[KenB259]

My two cents on calipers is this, also to add a little background, I have been using precision measuring instruments for 40 years. Vernier calipers are for young eyes, definitely not mine anymore. A better choice would be dial calipers and even better than those would be the digital variety. My tool of choice for measuring pen barrels ,when they are approaching final size, is a digital micrometer. Hands down the best tool for this type of measurement. Buy a good one and it will last you a lifetime.


Sent from my iPhone using Penturners.org mobile app

 

[JohnU]

A tip for your ca finish. I like to use the plastic Nonstick Delrin bushings you mentioned. They are tapered so you get a snug fit in whatever size tube your using. I only work one tube at a time. Depending on the blank material it isn't alway necessary to have a thick finish. If your filling in voids or open grain it may be thicker. If your having trouble getting the ends clean you might be using too much glue

If needed, start with the blue label thick filler. After I apply 2-4 coats I steel wool (#OOOO) it with the lathe on high to smooth out the surface. Then I apply 3-5 coats of the thin orange label, and lightly steel wool it again before switching to micro mesh and polish.

If the surface is already smooth just use the orange label GluBoost finish. 4-5 coats and finish as above. The white plastic bushings should just pop off with little effort. I use a razor blade along the ends to trim off the excessive glue.

Keep at it. There is a learning curve with any finish. After a while you'll be able to do it in your sleep.

 

[mark james]

All the above comments are a wonderful synopsis for finishing. An excellent resource! Well done guys.