turn pen blank down to bushing size--help!

[hotwire55]

I am having trouble turning down to my bushing size. I end up just a tiny bit proud at the nib bushing as with the other bushings. Do I actually want to trim down all the way to the bushing and then sand & apply finish? I have tried to search the posts and am not doing very well. Maybe, some of you guys can help me with this problem. Thanks! ---bobby moyers

 

[alphageek]

The number one tip is to get a digital caliper. The bushings should be something to get you to the 'ballpark' when you are rough turning, but all the best penmakers measure the actual parts and turn to match that. Something as small as a couple of thousandths can be felt.

 

[seamus7227]

Dean nailed it!

 

[azamiryou]

This is a tricky area! +1 on calipers.

If you have new and accurate bushings, you probably want to cut right down to the bushing diameter. But if you do this with the bushing there, you'll likely cut the bushing a bit, reducing its diameter slightly and possible getting black metal dust into your the wood.

If possible, do your finishing cuts, sanding, and finishing without bushings (turning between centers) or with slightly undersize bushings. This will help keep from sanding/cutting the bushing and getting bushing dust in the wood. You can easily turn your own undersize bushings from delrin; these also have the advantage that finishes don't adhere to them very well.

 

[hotwire55]

The number one tip is to get a digital caliper. The bushings should be something to get you to the 'ballpark' when you are rough turning, but all the best penmakers measure the actual parts and turn to match that. Something as small as a couple of thousandths can be felt.

I do have a nice set of calipers & I am using them, Just didn't know how close you guys were actually turning to the bushing. Thanks much! --- bobby moyers

 

[hotwire55]

This is a tricky area! +1 on calipers.

If you have new and accurate bushings, you probably want to cut right down to the bushing diameter. But if you do this with the bushing there, you'll likely cut the bushing a bit, reducing its diameter slightly and possible getting black metal dust into your the wood.

If possible, do your finishing cuts, sanding, and finishing without bushings (turning between centers) or with slightly undersize bushings. This will help keep from sanding/cutting the bushing and getting bushing dust in the wood. You can easily turn your own undersize bushings from delrin; these also have the advantage that finishes don't adhere to them very well.

Matthew, I am trying to turn down to the bushing, and I am getting very close, but I invariably nick the bushing some, no matter how much I try to prevent that from happening. I have been doing my finishing between the lathe centers without using the bushings and that is working out real well. I think turning down to the correct bushing diameter measured with a caliper & sanding & applying the finish should keep me close enough. Is that safe to say? Thanks for the help! ------bobby moyers

 

[azamiryou]

Matthew, I am trying to turn down to the bushing, and I am getting very close, but I invariably nick the bushing some, no matter how much I try to prevent that from happening. I have been doing my finishing between the lathe centers without using the bushings and that is working out real well. I think turning down to the correct bushing diameter measured with a caliper & sanding & applying the finish should keep me close enough. Is that safe to say? Thanks for the help! ------bobby moyers

I used to go right down to the bushing with my skew, and it worked well enough. My bushings gradually got smaller and once in a while I stained a blank.

But yeah, it's safe to say that if you turn down close to the bushings, then switch to between centers and use calipers to get to final size, you'll have better results. The only thing I'd change is where you said, "turning down to the correct bushing diameter"... you want to turn down to the correct pen component diameter. Even within the same brand, style, and plating, there can be several thousandths difference. Across different platings in the same style, it can be even more of a difference. And of course from brand to brand, all bets are off, even if the pen style and nominal tube size are the same. For the best results, measure the actual parts for the kit you plan to put on that blank. Also, most kit parts aren't round, so measure at several points. Your target is the largest reading. When taking measurements, don't squeeze the parts - the part can flex and give you a low reading.

Pay attention at first - and perhaps even keep notes - to get an idea of how much you take off with sanding and how much you build up with finish (and how much you take off with sanding/posishing the finish, if you do that). Also note how you like the feel of different sizes relative to the pen components.

In general, you want the final size to be the same as the pen component. Even the tiniest bit smaller is usually bad, because the sharp edge of the component is easy to feel when it sticks up over the barrel. On the other hand, a few thou over is much less noticeable, especially if you - very slightly - round the corner during polishing. If you're turning wood, remember that it is not stable, and will tend to shrink and expand. I make wood a few thou oversize so that when it shrinks, the components don't end up sticking up proud of the barrel. Try it different ways and see how you like the feel of each.

 

[alamocdc]

I always double check the size of my bushings to be safe first. One school says to take the barrel just proud of the busings and let sanding do the rest. And that works... if you start sanding with a course enough grit. I don't.

The other school says to just kiss the bushings with the skew before you sand. And that works... if you get the barrels smooth enough to start at 320 or so.

 

[Lenny]

Digital calipers are definitely your best friend here. Be sure to measure each component and not just rely on what the instructions say they should measure! For example the nib of one set of components I use has varied from .329 to .357 ....
I like to turn close to the bushings. And then place the blank between 60 degree centers with no bushings to turn and sand to final dimension. Sneek up on it, checking with the calipers frequently. With wood you will want to be just undersized to allow for the CA thickness build up.

 

[hotwire55]

turning to bushings

Thanks Matthew!

I have looked at some of your ink pens and other work, and am amazed at the true craftsmanship you exhibit! I really like your work! My goal will be to produce your kind of quality!

I never thought about ink pen parts varying in size from one pen to another. You have probably saved me untold hours of mental stress just trying to understand a few things that are critically impotant to fit & finish. Thanks so much for helping a newbie! ---Bobby Moyers

 

[hotwire55]

I always double check the size of my bushings to be safe first. One school says to take the barrel just proud of the busings and let sanding do the rest. And that works... if you start sanding with a course enough grit. I don't.

The other school says to just kiss the bushings with the skew before you sand. And that works... if you get the barrels smooth enough to start at 320 or so.

Using a skew chisel & sharpening one is foreign to my woodworking background. I do sharpen regular wood chisels and hand block plane blades on my belt sander though. I recently purchased a 3/4" rounded edge Taylor & will be trying to get an edge on it. I have been turning to final size with a Woodchuck Pen Pro & finish sanding between centers. I know this Skew thing is the way to do it, but its just going to take me time to get that thing to cooperate with me. Thanks Billy! --Bobby Moyers

 

[azamiryou]

Thanks so much for helping a newbie! ---Bobby Moyers

Since you're a newbie, one more piece of advice: don't sweat it. Aim for perfection, but remember that not every pen will be perfect. Thanks for checking out my work, I'm glad you like it! When comparing to your own work, please keep in mind you only get to see what I choose to show:biggrin:. I have plenty of failures and mistakes.

Another really cool piece of advice I've heard for learning any new skill: focus on improving one thing at a time. For each pen, have a goal of just one thing you want to do better than your last pen. If it's the fit of the parts as we're talking about in this thread, don't go trying a different finish or using unfamiliar chisels or whatnot, just follow your regular routine except the way you're getting to size. Or when you're learning to use a skew, focus on that and don't also try to improve your fit.

Final bit of advice: have fun. As long as you're having fun, you'll keep doing it. And as long as you keep doing it, you'll get better, with or without advice from here. If trying to follow all the advice has you frustrated, forget the advice and just go back to making pens and having fun.

 

[hotwire55]

Digital calipers are definitely your best friend here. Be sure to measure each component and not just rely on what the instructions say they should measure! For example the nib of one set of components I use has varied from .329 to .357 ....
I like to turn close to the bushings. And then place the blank between 60 degree centers with no bushings to turn and sand to final dimension. Sneek up on it, checking with the calipers frequently. With wood you will want to be just undersized to allow for the CA thickness build up.

Thanks Lenny!
Your input is always appreciated and the help I've received from everyone on this forum is helping me to learn quicker. The Skew I'm working with will help me get down to that finish size and then I'll put the blank between the 60 degree centers for finishing up. Thanks Much! ---Bobby Moyers

 

[Joe Burns]

Lots of good advice here. I used to turn down to the bushings but dont anymore. I turn close to the bushings and try to make sure I dont contact the bushings with my tools. I mostly used a carbide cutter now instead of a skew to turn. Once close to the bushings I start measuring with my calipers. I then sand to bring the piece almost to the final size I need, measuring several times as I go.

Use the size of your pen components for the final size you need instead of relying completely on the bushings. You also may need to make allowances for the finish depending on the finish you are using. Doing this has helped my fit tremendously. Takes longer but the results are worth it.

Above all have fun and ask questions.

Joe

 

[Rodnall]

Hey Bobby, I'm a fairly new turner also and was having a little trouble with the skew until I watched a video by capn eddie and changed the grind on my skew. Here is a link shaprskew.avi - YouTube

Hope it works

Rod

 

[rherrell]

What Lenny said.:biggrin:

 

[greggas]

Already been said....but having been through the same thing....Digital calipers...a must ...especially since the size of bushings tends to,vary and then certainly gets smaller with each sanding

 

[hotwire55]

Many thanks to everyone for your help with this matter! Your guys have been through this I'm certain of that, and know how it just takes time to learn the required skills. I am truly enjoying the challenge and all the good friends I'm meeting along the way add to that experience! Many thanks to everybody!----HAVE A BLESSED DAY!!! ---- Bobby Moyers

 

[nava1uni]

I agree with the use of calipers and the other thing that I find useful is to lightly soften the edge with micromesh or 2500 sandpaper so that when it is assembled the parts have no sharp edge. This creates an almost seamless transition between the barrel(s) and the components.

 

[hotwire55]

Cindy, I appreciate the advice! I'm always open for help and I have a lot to learn! Have a great day! --- Bobby Moyers

 

[azamiryou]

Here's a diagram - of course the sizes are exaggerated! Were only talking about a few thou in real life.

A is "perfect". But it's easy to miss and end up with B or C. Both are bad, but C is worse. If the blank is wood or something else that shifts, a pen that starts out as A can change to B or C over time.

D is good. As you round over the corner on the blank, be careful not to round it too much and get E. F is what happens if you shoot for A, but carelessly knock the sharp corners off during sanding/polishing. (Using full-size bushings for all work protects the corners, but has its own problems such as contaminating the blank with bushing dust.)

 

[Ulises Victoria]

I have been following this thread because I also think that matching barrel/component is one of my my weakest points so far.
Matthew's diagram is most informative. I am seriously thinking about relying more in measuring pen components with digital calipers and turn using that as my guide, instead of the bushings.
Thanks all for the information.:good:

 

[panamag8or]

I have been following this thread because I also think that matching barrel/component is one of my my weakest points so far.
Matthew's diagram is most informative. I am seriously thinking about relying more in measuring pen components with digital calipers and turn using that as my guide, instead of the bushings.
Thanks all for the information.:good:

Agreed. This is definitely the next step in my evolution.

 

[hotwire55]

Here's a diagram - of course the sizes are exaggerated! Were only talking about a few thou in real life.

A is "perfect". But it's easy to miss and end up with B or C. Both are bad, but C is worse. If the blank is wood or something else that shifts, a pen that starts out as A can change to B or C over time.

D is good. As you round over the corner on the blank, be careful not to round it too much and get E. F is what happens if you shoot for A, but carelessly knock the sharp corners off during sanding/polishing. (Using full-size bushings for all work protects the corners, but has its own problems such as contaminating the blank with bushing dust.)

Thanks for the diagram! This turning and finishing of the pen blank to the correct dimensions is such a critical issue for me. I really like the flush fit of #A example and will set it as my goal. As stated earlier, quality is important to me and I'm certain for many others as well. Thanks again!
----Bobby Moyers----

 

[flippedcracker]

This thread is awesome. Really good advice in here. I'm getting a dead center today, and hopefully that will help in my fits. No matter what I do, I always seem to be too big on the barrel and have it sticking out over the components. I think that's the one thing holding me back.

 

[hotwire55]

I'm still working on the barrel fit to the components myself. I've been turning the blank about .002 undersize and applying about 10 coats of thin CA overall with micromeshing at 5 coats and again after the last 5 coats. I am noticing that I'm still undersized a little after all the finishing is done to the blank. I believe I will use 15 coats of thin CA and see how that works for me. I prefer the BLO & thin CA for a finish, and I don't do well with the medium at all. Yes, the help I received from everybody with this post is really helping me along! Thanks! --Bobby--

 

[mpex]

I took a metal file to my bushings and turned them down around 1mm below where I need to be to match my kit components. Once I get close, I use digital calipers to get to the exact right size (hypothetically, hence my problem. This is working out pretty well. I typically turn down with a rougher or skew to around 0.2-0.5mm above my kit size. Then I take sand paper (150,240,320,400,600) to TRY to get down to 0.05mm below the kit size. Then I build it back up with CA. The problem is that I always turn it down too much and end up endlessly have to apply CA to build it back up. I'm using Digital Calipers the entire time but I just can't seem to get it right. I guess I have to check more slowly or go down to a finer grit when I get close. Any additional help or ideas?

 

[hotwire55]

I have learned to measure all my components and turn about .001 undersize. Still got a bunch to learn! Bobby