Brass tube question

[InkyMike]

Hello all

I might be turning some blanks ahead of actually purchasing some kits (but knowing which kits I'll be using.) I've been looking around and it seems that you can buy 7mm brass tubing, but some of the inside diameters differ (I've seen .2mm, .4mm, .5mm, etc.)

Is there a standard ID across kits?

Thanks!
Michael

 

[Edgar]

Be sure to buy your 7mm (or any other tubes) from a pen kit supplier.

The tubes that we call "7mm tubes" actually have an OD of 6.8mm (0.268") and an ID of 6.3mm (0.248"). The 7mm designation refers to the size of the drill bit that we use to drill the blanks for those tubes.

If you buy "7mm brass tubing" from other sources, they will likely have an OD of exactly 7mm and would not be suitable for general purpose pen turning.

The tubes will be fairly consistent from one pen kit manufacturer to another. In general, pen making does not require highly precise parts, so you can expect slight variations from those 6.8 & 6.3 mm dimensions, even from the same supplier, but not enough to matter.

 

[Kenny Durrant]

Another thought is that if you know what kits your going to use most pen kit suppliers sell precut to size tubes.