How much to undersize a blank for a CA finish

[Stephen]

I normally undersize a wood blank to 0.006" + and build up with CA above the pen components dimensions and sand/polish to component size. This brings the final CA finish to approximately 0.003" thick. Is this adequate?
What is the norm?
Like to hear from the experienced pen makers.
Thanks

 

[rherrell]

I don't allow anything. I make the unfinished barrel the EXACT same diameter as the fittings. My CA adds about 2-3 thou. but my philosophy is to NEVER, and I mean NEVER make the barrel SMALLER than the hardware. You can really feel it if the barrel is smaller but a few thou. over is hardly noticeable.

 

[JimB]

The final thickness of the ca finish, like many other things, is personal preference. Some will go with many coats for a thicker finish to get more depth while others go thinner for a more natural look.

 

[Constant Laubscher]

I don't allow anything. I make the unfinished barrel the EXACT same diameter as the fittings. My CA adds about 2-3 thou. but my philosophy is to NEVER, and I mean NEVER make the barrel SMALLER than the hardware. You can really feel it if the barrel is smaller but a few thou. over is hardly noticeable.

I disagree, I always cut the ends of the barrel slightly smaller and then buildup with CA. I use a skew as a scraper and turn the CA smooth and to the same dimension as the bushing, then I would sand and polish.

The barrel should never be oversize or under size, in my opinion it looks terrible and is poor workmanship.

Everyone set there own standards on what looks good.

 

[Justturnin]

The barrel should never be oversize or under size, in my opinion it looks terrible and is poor workmanship.

+1 on this. I go just under and use Sandpaper to get it there. Then I kiss the edge by the bushing w/ my 1/16 parting tool and build back w/ CA. If I go to low I get the Medium out but if I get it just right the thin will work at about 20-25 coats. The Thin dries fast but about every 5 coats I spray w/ accelerator (aresol not pump)

 

[PenMan1]

I agree with Constant.

You can feel an undersized fit. BUT, you can SEE an oversized fit.

I, too slightly undercut and build up slightly oversized then sand or skew back until the trim rings fit perfectly. It is a LOT more work, but I feel better about the pen.

 

[pianomanpj]

Agreed with Constant and Andy. I usually go a few thousandths shy of the components, and then build up with CA to a few thousandths proud. Sanding and Micromesh brings it to being spot on. Since I turn between centers, I can remove the blank easily and check with calipers OFTEN! For me, anything UP TO 1/1000 oversize is acceptable, but NEVER ANYTHING undersize! YMMV

 

[Texatdurango]

.005" or .006" is just fine. I frequently go a little deeper and build up with CA then finish back down to component size. Most people seem to react to the finish in the same way...."WOW, that has such a DEEP look to it"

When the buyers are happy, my likes and dislikes are secondary!

 

[watchman7]

Like most so far I undersize about .004 then build up the CA to oversize at least .002. Micromesh will usually bring it spot on or a little oversize. Never, ever undersize the the barrel.

 

[Stephen]

Thanks everyone. Glad to know my procedure is the norm.
I do a final light touch up to the ends of the barrel with 12000MM by hand before assembly to eliminate any tiny sharp edges that may have been missed.

 

[kovalcik]

I do a final light touch up to the ends of the barrel with 12000MM by hand before assembly to eliminate any tiny sharp edges that may have been missed.

+1 on breaking the sharp edges. I usually lightly sand the corners of the blank. Just a little rounding makes a slightly oversize barrel unnoticeable.