Tips for Turning Down to Bushings

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Mongo44

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Jun 15, 2020
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Connecticut
Hello, I have recently started making pens and pencils. Over the past month I have developed my method for finishing (2 coats of thin CA & 8 coats of medium CA), followed by micro mesh, and then plastic polish. This often given a beautiful finish, but seems too affect my transition from kit components to blank. This could also be my fault by not turning the blank down enough. I have a square carbide rougher, round carbide tool, and diamond "detailing" tool. Usually Ill use the square rougher to get as close as possible to the bushings, then take light passes with the rounded tool. Followed by 180-600 sanding, at this point it usually appears to me that my blank is even with the bushings. Yet, once I assemble the pen after finishing I often notice the slightest overhang from blank to cap, center band or nib. Any tips to help get the blanks perfectly lined up with the bushings so there is a seamless transition. Here are pictures showing what I am referring to. Thank you all for the time and help, I'm excited to learn!

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sorcerertd

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Sep 30, 2019
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North Carolina, USA
Welcome aboard, Andrew! You definitely have cut a bit further down than the bushings and then build your finish up slightly past them again before you start the smoothing and sanding of the finish. There's plenty of people here with a lot more experience than me that will have good info. I have found that it mostly just takes lots of practice!
 

Jolly Red

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May 4, 2012
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Location
Carterville, IL
1. Check the diameter of the bushings you are using. Use a good micrometer or calipers to check to the 0.001". If the diameter is to the finished diameter of the kit, they are not allowing for the thickness of the finish. If they are oversized, they should be replaced or turned to the right diameter (using a metal turning lathe).
2. Stop using bushings to get the final diameter and use calipers. Use the bushings to get close to the final diameter, then "turn between centers" to the final diameter, using calipers to get the final diameter with an allowance for the thickness of your finish. Look through the pen turning forum for posts on "turning between centers".

You will notice that both of these use calipers for measuring. They don't have to be the expensive ones that machinists use, you can get them from Harbor Freight and they will do the job.

Good luck in learning to turn pens. This can be addictive, and I don't know of any 12 step program for recovering pen turners.
Tom
 

jttheclockman

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Feb 22, 2005
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NJ, USA.
This gets brought up many times and in fact I believe there is another thread going on right now with something like this. To sum it up and give a short version, bushings are only guides and not be all end all measurements for any kit. They get you close. Get yourself a good set of digital calipers and work from them. Measure the components and mark them down. Measure both ends of each tube components because many times they are not always the same. I will get as close to bushings as possible then turn the final bit down between a live and dead center. Using the calipers to hone in on dimensions needed. Now if it is a wood blank then I will over cut the blank some to allow for CA build up. With time you get a feel for this. Then I sand and MM down to final dimensions. Good luck.

By the way the last tool and sometimes only tool that touches any pen blank I work on is a sharp skew. Gets me to my goal every time.
 

wouldentu2?

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Jan 27, 2011
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Oak Creek WI
It looks like the top and bottom are proud quite a bit. Get a caliper, dial or digital and measure the metal parts where they meet the blank and turn the the blank to that dimension or a little less. Then do your final sand and CA . Or for that type of pen leave it slightly larger and slightly curve it down to the metal. Sharp edge then is not an issue, it makes a better looking pen, I think.
 

magpens

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Feb 2, 2011
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Coquitlam, BC, Canada
Hi there Andrew !! . Warm welcome to IAP !! 😀

I won't try to address your question above. . Just wanted to extend a welcome !

I will say, though, that the issue you are wanting help with is one which every one of us has had a struggle with when beginning pen turning.
We each have to develop techniques to deal with it to the best of our ability. . I will also say that you don't have to strive for an exact match between the levels of the metal hardware and the wood blank. . I feel it is OK for the wood to be slightly above the metal, but not the other way around. . Eventually you learn to compensate for the extra height added by the CA finish you apply to the wood after sanding. . It is something you kinda get a feeling for. . When I say "slightly above the metal", I mean about 0.005" or less of diameter oversize. . That's not very much.
Let your own judgement be your guide.

As others have already said, it is a good plan to buy a set of digital calipers and measure the metal pieces, writing down the measurements.
You can then use those measurements as a target while you are turning.

Many of us have actually dispensed with bushings altogether and now rely on measurements only during our turning.

Rather than use a mandrel and bushings, we use the method called "turning between centers", or TBC.
You should do a search for that method here on IAP to get the idea of what it is about and then plan to use that method in the near future.
A mandrel and bushings is probably a good way to start but you will want to make the transition to TBC.
 
Last edited:

sorcerertd

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I wasn't going to throw TBC at you yet, but I guess there's no reason not to. It's a lot more accurate than using bushings, which are often out of round enough to make your pen barrel only meet the kit hardware on one side anyway, I just got started on this recently and it has made a big difference. You definitely need calipers for TBC.
 

mnerland

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Mar 26, 2019
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59
Location
Bowling Green, KY
I'm definetely far from being an expert, but here's my observation. I can clearly see the brass tube through the front end of the pen. Maybe this tube should have been painted before. So I'm assuming the blank is some type of acrylic. Why, then...10 coats of CA. I'm thinking finishing without CA, just MM. Back end is wood and not turned to bushings. Sounds like you have some expensive turning tools and nervous of getting close. I turn with cheap HSS, but would like to try some of these nice tools. I've never had that big of a ridge when I turn to bushings and finish after. Check your bushing diameters with the caliper as mentioned.
 

Mongo44

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Jun 15, 2020
Messages
22
Location
Connecticut
I'm definetely far from being an expert, but here's my observation. I can clearly see the brass tube through the front end of the pen. Maybe this tube should have been painted before. So I'm assuming the blank is some type of acrylic. Why, then...10 coats of CA. I'm thinking finishing without CA, just MM. Back end is wood and not turned to bushings. Sounds like you have some expensive turning tools and nervous of getting close. I turn with cheap HSS, but would like to try some of these nice tools. I've never had that big of a ridge when I turn to bushings and finish after. Check your bushing diameters with the caliper as mentioned.

I’ve seen painting tubes once before in a watch part casting video, great tip. I also think 5min epoxy might help create a more uniform bond (as disgusted in another thread). I use 10 coats CA on wood and hybrid pens (the pictures are from a single modified pencil with a hybrid maple burl blank). I do this because I don’t know how to get a glossy finish on the wood and resin without just doing a nice CA finish and MM sanding. If you have any tips for finishing hybrid blanks I’d love to know. I will defiantly invest in nice calipers soon. Again I am extremely new to all this but I got the cheapest carbide set of tools possible ($100 for all 3) I’ll drop an amazon link to the product. Although shorter then most tools I’m sure you’ll be able to produce so great products if you wanna try them out, thank you for the help!

3 piece Carbide Mini Turning Tool Set With Foam Lined Case Perfect For Turning Pens Pencils Tops Goblets Acorns Bottle Stoppers or any Small to Mid-Size Turning Project (3pc Carbide Tool Set) https://www.amazon.com/dp/B01FWEX6OA/ref=cm_sw_r_cp_api_i_SZy6EbTXE8Q92



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Mongo44

Member
Joined
Jun 15, 2020
Messages
22
Location
Connecticut
Hi there Andrew !! . Warm welcome to IAP !!

I won't try to address your question above. . Just wanted to extend a welcome !

I will say, though, that the issue you are wanting help with is one which every one of us has had a struggle with when beginning pen turning.
We each have to develop techniques to deal with it to the best of our ability. . I will also say that you don't have to strive for an exact match between the levels of the metal hardware and the wood blank. . I feel it is OK for the wood to be slightly above the metal, but not the other way around. . Eventually you learn to compensate for the extra height added by the CA finish you apply to the wood after sanding. . It is something you kinda get a feeling for. . When I say "slightly above the metal", I mean about 0.005" or less of diameter oversize. . That's not very much.
Let your own judgement be your guide.

As others have already said, it is a good plan to buy a set of digital calipers and measure the metal pieces, writing down the measurements.
You can then use those measurements as a target while you are turning.

Many of us have actually dispensed with bushings altogether and now rely on measurements only during our turning.

Rather than use a mandrel and bushings, we use the method called "turning between centers", or TBC.
You should do a search for that method here on IAP to get the idea of what it is about and then plan to use that method in the near future.
A mandrel and bushings is probably a good way to start but you will want to make the transition to TBC.

Thank you so much for the warm welcome. I have seen a little on TBC via youtube and think it’s defiantly a jump I will make in the future. As you said I need to do more research, and gladly will!


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TonyL

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Joined
Mar 9, 2014
Messages
8,152
Location
Alpharetta, GA 30004
I turn slightly proud (just enough to barely "grab" the tip of my fingernail) and create a small radius at the ends to give one the illusion of the barrel material meeting the hardware perfectly. Then I sand and finish. I am probably one of the few turners that don't allow for height or depth of the finish. What I described above is not a recommendation; it is just the way I like to make pens. Enjoy!
 
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