Pen Kit Manufacturing Tolerances

[JimGo]

I received some very good feedback on the pens I posted last night in the Critiques forum. One thing that I've pretty consistently done is to turn the barrels slightly under the diameter of the components to which they are mated. So, I'm probably going to start using a micrometer to double-check my sizing before I start sanding (i.e., leaving a little extra before I start sanding) and as I work my way through the more aggressive grits. What I'm not sure of is whether I need to mic every individual component, or if the manufacturing tolerances are such that the sizes are pretty consistent.

Any ideas?

 

[lkorn]

Jim,
The first thing I would do is to measure you bushing and components, then compare them. I've noticed that the PSI kits are not necessarily dead on, but other Berea and CSUSA are a whole lot closer. With the better kits, if I turn to the bushing and be carefull not to sand through them, I get a very accurate fit. Attention to details[]

 

[JimGo]

It's those last three words that are going to kill me Larry!

 

[alamocdc]

Jim, what grit do you start with? I used to start with 100, but it took a long time to get the sanding scrathes out so I moved to 150. Most of the time now, I can get by with starting at 220. It just depends on the type of wood and the finish left by your tools.

 

[woodbutcher]

It kinda depends I usually never start with anything Larger than 150 and much of the time stsrt @ 180 or 220. I usually stop @ 1500 or 2000. I use the M M system for ca finishes and acrylics, hope this helps

Jim[]

 

[JimGo]

I start with either 120 or 180 depending on how the wood looks. I may try starting with a higher grit, which should leave more meat on the barrel.

Thanks Billy!

 

[alamocdc]

Wrong Jim, Jim! [] But I think he will get the point. [] Based on your original post (JimGo), you may be starting with a much too aggressive grit.

 

[Dario]

I am not bragging but I usually start at 320...sometimes 220 but very seldom. If I ever feel I need a rougher grit...I pull out the skew back out instead.

I have rougher grits...I think 60, 80, 120, 160, and 180 but they not being used now.

 

[Geo in Winnipeg]

With most wood I start at 220 (sometimes 320) and then MM. I try to do a lot of measuring and have a few sets of calipers so I can set 1 for nib, 1 for CB and 1 for the finial of the kit on the lathe at the time --- but sometimes I still screw up and take just a tad too much off.[]

 

[alamocdc]

Looks like we were typing at the same time, Jim. I forgot to mention something. The 220 is only with wood. With plastics, whether it be homebrew PR, bowling ball, or whatever, I start by wet sanding with 400. Never anything any more aggressive. It just puts more scratches in and takes way too much to get them out. Then I move on to MM.

 

[JimGo]

Billy,
For the plastics, I actually just use the MM for Corian/Acrylic. I don't even bother with standard sandpaper. Of course, I wet sand with that MM.

 

[Randy_]

This subject was covered a while ago in another thread.....and the conclusion was that there is a significant variation......especially between different lots of pens. If you want to do the best work, you need to measure every pen. You may decide, after a while, it is not necessary to do so to satisfy your particular standards. If so, then discontinue the practice.

 

[wayneis]

It's really a good habit to measure all of the parts as every once in a while they will change just a touch between runs.

Wayne