Thursday, October 05, 2006

Plus or Minus How Much?

Last week when I was using my Waterman Hemisphere pencil it ran out of lead. So, I grabbed the tube of 0.7mm Staedtler leads out of my desk draw and put three sticks of lead into the magazine. Then I started activating the lead advance mechanism and a stick of lead just fell right out of the tip. Then another. Stupid me, I had obviously put 0.5mm leads into my 0.7mm pencil. So I grabbed the Staedtler tube of leads again and ….no, they were 0.7 leads. Stupid Staedtler, they had obviously put 0.5 leads in a 0.7 tube. So I pushed one up the lead sleeve. Ummm, well it seemed to fit tightly and actually be a 0.7mm lead. But again it just fell straight through when I activated the lead advance mechanism. Then one of the lead sticks actually seemed to work. So I played around a bit. All three leads were 0.7mm but two of them just kept falling straight through and the third one didn’t. One explanation seemed to be that there was a minute difference in the diameter of the leads.

I’m sure you will be surprised to hear that a guy like me just couldn’t let something like that go by! An investigation would have to be launched.

Out with my micrometer! Mine is a 0-25mm, in 0.01mm increments – that’s about 0–1 inch in 0.0004 inch increments. The small piece of original unknown brand lead in my Waterman measured 0.715/0.72mm diameter. The two Staedtler leads that kept falling through measured 0.685/0.69mm and the one that worked measured about 0.695mm. Well, that seemed to support my theory that the problem was related to the lead diameter.

So, just what size are 0.7mm leads? 0.7mm plus or minus how much? Obviously Staedtler think 0.685 – 0.695mm is OK, but Waterman don’t because that size doesn’t work in their pencil. I grabbed a few 0.7mm samples from other brands and got to work with my micrometer. I’ve rounded the results to 0.005mm bands as there is a bit of variation in each piece of lead, and from one piece to another of the same brand.

Mitsubishi Uni = 0.685 – 0.69mm
Staedtler = 0.685 – 0.695mm
Pilot Eno = 0.70 – 0.71mm
Waterman = 0.705 - 0.71mm
Faber-Castell = 0.71 – 0.715mm
Pentel = 0.715 – 0.72mm
The original piece in my Waterman = 0.715 – 0.72mm

In all my years of penciling, I don’t think this has ever happened to me before.


Stephen said...

Wow, I'm impressed. These little annoyances are often accepted as part and parcel of modern life, and few of us would have the ability or desire to diagnose such a problem. Good for you.

So how much to micrometers go for? :)

kiwi-d said...

Ah, the trusty micrometer. No serious nutcase can get by without one! I'm not really up with pricing these days - I imagine US$35 would get you an average one, a lot more for a really serious one. I'm sure that World Wide Interweb Net thing will be loaded with heaps of folk wanting to sell you micrometers, calipers, etc.

khairul said...

well it caught my eye that you have PILOT ENO in your collection. but i didnt see any review on them. ive been looking to buy the color lead only but after reading your recent post,it obvious that most likely it will only fit to the PILOT ENO pencil only.

Could you point me where you buy the ENO color lead?im from australia and it will be much easier if its from australia or new zealand.

soon i might start blog on mechanical pencil as well :)

kiwi-d said...

Hi Khairul. Well I'm sure that the vast majority of pencils will fit the vast majority of leads so I wouldn't be too concerned about Pilot Eno only fitting Pilot pencils.
If you use "search this blog" on "Pilot" you will bring up some stuff on The Lead Cup where Pilot Eno was involved.
You don't see Pilot leads around much in NZ. I bought mine in with some other stuff from the US.
I think you'll need to do a bit of web searching to find a retailer. Should be a few in Australia. There are a few sellers on eBay, etc, particularly of the coloured leads. Happy shopping.

limepickle said...

I'm suffering the same same problem with my Waterman. Mine's a 0.5mm but Pentel leads always fall through.

Where can I get hold of Waterman leads in the UK? It's no fun having a fantastic Waterman and not being able to use it.

kiwi-d said...

Hello Limepickle. Well thats interesting, but annoying for you though. Perhaps its a general thing that Waterman mechanisms are little bit fussier than other brands.
As for getting hold of Waterman brand leads in the UK I can only suggest lots of web searches and/or contact Sanford UK to ask if they bring Waterman leads into the UK and who they distribute to.

Anonymous said...

I'm sitting here laughing...
I just got a Waterman pencil and thought I'd be ahead of the game by looking up leads...Now I know not to mess around with other leads...
Thanks for all your measurements...(I also have a micrometer...because I'm a jewelry artist who works in metal and stones...not sure I would have thought to use it...)

Sapphire said...

Four years later and I still haven't learned.
My Cross pencil ran out of lead. The Pentel tube ( I usually use Pentel) was also empty, but a search revealed some Staedtler leads in my drawer.
The same thing happened - they fell through.
It seems that Staedtler are on the thin side for several pencil brands.
I don't have a micrometer though.

Kiwi-d said...

Yep, it's a pain when it happens. Had it happen to a Lamy just this week.