Pencil Leads

[J.A.F.E.]

OK not the most exciting topic on the planet but some interesting stuff anyway. In a recent thread on the new arrivals from the 11/11/18 Long Beach swap was some drafting leads.



They are used in a mechanical pencil and are 2mm in diameter. Like regular wooden pencils they come in a variety of darknesses.

Pencil leads run on a scale of hardnesses the harder the lead the lighter the line. The softer the lead the darker the line. A hard lead keeps it's point while a soft lead dulls rather quickly. The leads are made from basically graphite and clay. The more clay the harder the lead. Graphite needs the clay binder to stay together. The graphite and clay is mixed to the desired ratio in a slurry and extruded then baked. It's the same for the leads that end up in a wooden pencil. Usually in a wooden pencil the harder the lead the thinner the diameter of the lead and the softer leads are larger diameter leads.

Lead hardness runs on a scale from about 8 or 9B (very soft) to B, HB, F, H to about 9 or 10H. One interesting thing about the leads is the numbering system is pretty much universal but the actual hardness/darkness varies from manufacturer to manufacturer or sometimes even across different product lines within the same company. That's why from about 8 or 9B and about 9 or 10H. Some stop at 6 or even 4B and 6H.

A regular #2 pencil is about HB. You can get pencils from #1 (B), #2, #2.5 (F), #3 (H) and #4 (about 2H). Some manufactures have or will custom make intermediate numbers. The #1, #2 scheme is an American system by the way.

Just as an aside Henry David Thoreau was in the pencil making business with his father John. The whole craziness with Walden Pond and his books was financed by the pencil business.

[mdlbldrmatt135]

I still have my "stash" of drafting stuff from College.....  even from 1996-1998 we spent 50% of our time doing manual drawings and the other 50% doing CAD work.

I pull the stuff out every now & again for layout work on my projects.  I feel knowing how you would have done it on the drawing board gives you an advantage in the world of CAD, especially on the trickier stuff.

[J.A.F.E.]

If you can do it CAD is a great aid but certainly no substitute for knowledge and experience. Good drafting is art.

[goodfellow]

It was one of my favorite classes in High School and in College. I still have the rotating lead sharpener, several T squares, triangle sets, and architect scales sitting in a box on my office shelves. Sometimes they still come in handy ---             

[fatfillup]

It was one of my favorite classes in High School and in College. I still have the rotating lead sharpener, several T squares, triangle sets, and architect scales sitting in a box on my office shelves. Sometimes they still come in handy ---             

Haha, I still have the same stuff too.  Only had mechanical drawing in my freshman year at VA Tech.  Favorite class for sure.  Turns out you have to study a lot to be an engineer.  Transferred to Towson University to get a business degree. 

And yes they will get used from time to time.  Have no idea how to do Cad,,,,,,,,,,,,,,,,,though I was called a cad once

[J.A.F.E.]

There was a really nice Leroy letting set really cheap at the swap with a bunch of fonts. I used to drool over those but they were way out of reach for me. I came really close to snagging this one but I'll just never use it and I don't want to start yet another collection.

[DeadNutz]

Thanks for the hardness chart. Now I will be able to check my boxes of leads and know the hardness. I have one drawer in a stack that holds the drafting stuff such as templates, pencils, beam compass parts, scribers and other assorted parts. We used to have to layout bolt circle patterns manually until I put a DRO on the mill which took care of that chore.

[oldnslo]

+1 on the sharing of the hardness chart. Was not aware of that for the mech pencils.

Tho I never took a drafting class, I watched pops (a GE engineer) sit behind his full sized drafting table in the den, with the full-on setup of tall drafting chair, drafting lamp, electric eraser (an oversized Dremel tool really), and all the drafting paraphernalia on the desk.

I was always on the lookout for a mech pencil over the years, and now have:

2 Faber-Castell pencils
3 boxes of leads (H and 2H) from Staedtler/Mars
the Dietzgen circular desk sharpener

They get used for the to-do lists and other occasional functions. I still refrain from using a slide rule 

Thanks for sharing this info.

[J.A.F.E.]

DeadNutz all of that manual stuff was a chore but in some ways fun and a nice sense of accomplishment once done. Pushing a few buttons is a lot faster

OnS I love all that stuff. I recall those huge erasers and drafting aids. Some of those were really cool. In addition to the lettering set I saw a really nice beam compass and came really close to snagging that. I'd love to find a spacing divider.

[fatfillup]

Electric eraser??  Never knew one existed

You guys are naming some things I never heard of before

Slide rule, wow, learned how to use one in high school and don't think I have used one since.  Wouldn't have a clue of how to use one.   I did do some long division by hand this summer just to see if I could remember how.  I did remember but it was a simple problem.  I wonder if they even teach that anymore

[mdlbldrmatt135]

Electric erasers were more for erasing ink on drafting mylar than plain old vellum.

[oldnslo]

Who knew? A YT video of the exact one!

[J.A.F.E.]

...   I did do some long division by hand this summer just to see if I could remember how.  I did remember but it was a simple problem.  I wonder if they even teach that anymore

I looked it up because your remark had me curious. Seems it's now controversial and not generally taught. But it also seems there are several methods of long division.

It's what I was taught and it seems natural to me and pretty easy if you are familiar with the multiplication tables. But I generally use a calculator.

[mdlbldrmatt135]

My drafting stuff, other than the long Vemco scales.

[slip knot]

Most of my drafting skills came from redlining prints for as builts. I learned not mention any drafting class' after that.

I got a couple of mechanical pencils and grab the leads when they show up. I use them more for carpentry work now. the thicker lead and darker color wins out over #2 pencils.