Gaps

[Hallelujahal]

Hi need a bit of advice. Sometimes I notice small or partial gaps between the turned blank and the pen section especially the nib sections or centre bands etc. Most of the time they are too small to really notice and maybe I’m being over fussy. But today I turned an acrylic blank on a high end fountain pen (Mistral) and had a small partial gap where the centre band meets the top section. In the end I turned the blank off and called it a day… I’d done a 14 hour shift yesterday
I really want to get this pen right. I guess it’s ensuring that I have a square face on the blank in the first place which I always endeavour to do. Any other ideas from the collective? I use a mandrel, would between centres make any difference?
Kind regards
Alex

 

[MikeC]

Hi need a bit of advice. Sometimes I notice small or partial gaps between the turned blank and the pen section especially the nib sections or centre bands etc. Most of the time they are too small to really notice and maybe I’m being over fussy. But today I turned an acrylic blank on a high end fountain pen (Mistral) and had a small partial gap where the centre band meets the top section. In the end I turned the blank off and called it a day… I’d done a 14 hour shift yesterday
I really want to get this pen right. I guess it’s ensuring that I have a square face on the blank in the first place which I always endeavour to do. Any other ideas from the collective? I use a mandrel, would between centres make any difference?
Kind regards
Alex

I had the exact same problem last week with a Justice fp I was making for my son. It looked as though the pen was slightly bent where the cap and barrel met. It turned out that the blank end was not exactly square, so I dismantled and put the blank back on the lathe with electrical tape around it to avoid marking it with the chuck, and used a square carbide tool very carefully to go at 90 degrees to the blank to square it. As I checked it as I went along it was easy to see where wood had been removed and I turned it until the "old" wood had just gone.
The pen then looked good when re-assembled.

Sounds like you are not getting your blank ends accurately square when you have glued in the tube.

I hope that helps

Mike

 

[Hallelujahal]

I had the exact same problem last week with a Justice fp I was making for my son. It looked as though the pen was slightly bent where the cap and barrel met. It turned out that the blank end was not exactly square, so I dismantled and put the blank back on the lathe with electrical tape around it to avoid marking it with the chuck, and used a square carbide tool very carefully to go at 90 degrees to the blank to square it. As I checked it as I went along it was easy to see where wood had been removed and I turned it until the "old" wood had just gone.
The pen then looked good when re-assembled.

Sounds like you are not getting your blank ends accurately square when you have glued in the tube.

I hope that helps

Mike

Thanks Mike as I thought

 

[Medwoodworx]

Hi need a bit of advice. Sometimes I notice small or partial gaps between the turned blank and the pen section especially the nib sections or centre bands etc. Most of the time they are too small to really notice and maybe I’m being over fussy. But today I turned an acrylic blank on a high end fountain pen (Mistral) and had a small partial gap where the centre band meets the top section. In the end I turned the blank off and called it a day… I’d done a 14 hour shift yesterday
I really want to get this pen right. I guess it’s ensuring that I have a square face on the blank in the first place which I always endeavour to do. Any other ideas from the collective? I use a mandrel, would between centres make any difference?
Kind regards
Alex

are you using a barell trimer or a sander? I am asking because sometimes the barell trimer leaves a few fibers uncut. Bare in mind that a barell trimmer needs sharpening from time to time.Cheers.

 

[flexi]

As above, it's your trimming... I use a disc sander and it's given better results. You could use a small snail countersink prior to assembly, it will improve the mateing surface

 

[TVS]

I use a disk sander dont like them barrel trimmers just in case the drilling is out a bit I part turn the blank on my mandrel after fixing the tube so that the out side is parallel with the tube then return it to the disk sander using a fence that is set square to the disk with perfect results every time

 

[Hallelujahal]

I use a disk sander dont like them barrel trimmers just in case the drilling is out a bit I part turn the blank on my mandrel after fixing the tube so that the out side is parallel with the tube then return it to the disk sander using a fence that is set square to the disk with perfect results every time

Thanks for this I’m going to start doing likewise

 

[Rich Aldrich]

I prefer between centers. My mandrels work well for a couple of pens then go out of round. Is the shaft and barrel trimmer out of round? You may want to chuck it up to see if it runs true. Debris in the tube can cause alignment issues. My two pence!

 

[geordie0928]

I give both end of the tubes a rub down before I put the pen together try that.

 

[jrista]

To add to what others have said, I use a disc sander with a pen sanding jig to get perfectly square ends on my blanks. I started using barrel trimmers, but I could never get the ends perfect. I've also had the reamer part get stuck in a couple of cases...honestly not sure why. In any case, you can make, or buy, jigs that will help you, using a set of center punches, get the blanks perfectly square to the disc. This really helps with ensuring there are no gaps between parts and turned blank.

 

[Penpal]

I found making devices,using a large sander several solid punches in four sets to get snug holding at right angles to the sander. I choose a 100 grit disk,always ready and just so accurate IMHO.

 

[Rich Aldrich]

I also clean my bushings after every use. I sometimes use Rick's sanding jig from IAP to do the ends.

 

[alpha1]

Once I have glued in my tubes I turn the blanks round then pop them in the Chuck on a metal lathe and trim the blanks back to the face of the tube with a carbide facing tool. Perfectly square every time. I then pop them onto the bushings and finish turning and polishing the blank.

 

[TrevorMcW]

Yep, partial turning of the barrel(s) to ensure good reference vertically then disk sanding with a jig to ensure good reference laterally.
Only tip I'd give otherwise is go easy feeding into the disk sander, even 100 grit is vicious and its difficult to creep up on the barrel end when you are blind to it.

Cheers