Sierra Fit

[StatProf]

Dear All,

I just put together two Sierras and had problems with the fit on both. On the nib side, the the turning doesn't fit flush. I don't know if it is that I somehow got some CA down on the end of the blank and it won't let me close it or if I somehow put a bevel on the end of the blank. The odd part is that the top end near the cap fits perfectly.

So, here's my thought . . . I think that the brass must be perfectly sized for the Sierra and I inadvertantly trimmed some of the brass off when squaring the blank.

Has anyone else had this problem? If my last hunch is right, do you just leave the wood a little long off of the end of the brass, and if so, does this cause any problems with splitting or chipping?

Thanks,
StatProf

 

[GouletPens]

Dear All,

I just put together two Sierras and had problems with the fit on both. On the nib side, the the turning doesn't fit flush. I don't know if it is that I somehow got some CA down on the end of the blank and it won't let me close it or if I somehow put a bevel on the end of the blank. The odd part is that the top end near the cap fits perfectly.

So, here's my thought . . . I think that the brass must be perfectly sized for the Sierra and I inadvertantly trimmed some of the brass off when squaring the blank.

Has anyone else had this problem? If my last hunch is right, do you just leave the wood a little long off of the end of the brass, and if so, does this cause any problems with splitting or chipping?

Thanks,
StatProf

What method are you using to square the blank? That could be the problem. Post a picture if you can, that will help.

 

[lwalden]

Sierra tube length is pretty forgiving- I've made sierras where the barrel ended up 1/16" shorter than the original tube length, without it causing the issue you described. Like Brian, I'd be interested in hearing what technique you use to mill the ends "square".

 

[StatProf]

I'm using a pen mill. I would say that the problem is the milling, but the gap is equal all the way around. It isn't like one side is touching and another side is not.

Thanks for the advice.

Kyle

 

[GouletPens]

I'm using a pen mill. I would say that the problem is the milling, but the gap is equal all the way around. It isn't like one side is touching and another side is not.

Thanks for the advice.

Kyle

Come to think of it now, I've had this problem before, where it just doesn't fit flush, and it has a small, even gap all the way around the nib section. I've made hundreds of these pens and it only happened a couple of times. I don't know what I did to fix it (I may have just shrugged, disassembled them and tossed the body) or if I even did. I'm actually curious if anyone else has solved this problem or know what causes it.:doctor:

 

[jkeithrussell]

It sounds like possibly the tube is sticking out very slightly past the wood. I've had this problem before with acrylics, but not with wood. A device like this:

http://www.penturners.org/forum/showthread.php?t=42098

or a small file can be used to make sure the ends are flush before final assembly. I recently bought one of the mills shown in the link and it is terrific for cleaning up CA.

 

[BigShed]

I have found that problem before asw ell, and not only on Sierras.

I do do 2 things to overcome this.

1 I put an internal chamfer on the brass tube with a hand chamfering tool

2 I then use a sander mill, like firefyter_mt's, to get the end of the blank/tube perfectly square.

This method is far superior to using a pen mill, either 4 or 6 cutters, and I can't remember the last time I used my pen mill.

I have made a few of these sander mills, good learning excercise for my metal lathe, and given them away to pen turning friends. Without exception they have been enthusiastic about them.

And if you don't want to buy a sander mill, just reverse the head on your pen mill and stick a disk of abrasive paper on it.

 

[maxwell_smart007]

I'm thinking a thin layer of CA on your bushings is making the bushing a bit proud of where it should be...

ANdrew