Sunday, February 13, 2011

On The Level

According to Don Rosebrook's excellent resource book American Levels and their Makers, the first levels, which consisted of an A-frame and plumb bob, were developed by the ancient Egyptians. 

Early Romans devised an instrument that's the ancestor to the type of level we're familiar with today.  They used a flat-bottomed trough containing water. When the water reached the same level along the inside walls of the trough, the device would be level.  Simple, but effective.

The use of a tube filled with fluid (wine, in this case) and an air bubble dates back to the 1600s and is credited to Dr. Robert Hooke, an English philosopher.

The levels that are featured in Rosebrook's book are primarily mid to late 19th century.  Woods used during that time include beech, boxwood, cherry, ebony, mahogany, rosewood, and others—heavy, dense, and stable wood.  High-end levels were made of rosewood and often had the most metal trim, some of which was ornate.

This is where my level comes in.  Like many women, I like shiny things.  But not so much on my fingers or ears as on my tools.

I spied what I think is probably a craftsman-made level (because of its shape) in Tony Murland's collection, and decided it was "the one."  A tiny image and one measurement (length) is my reference. Based on this I'm making my level with a .125" strip of brass and a cherry blank. The final dimensions will be 1.5" thick (inlcuding the brass) x 1.75" wide x 10.5" long.

I cut the brass on my new scroll saw (a stress-shopping purchase) with metal-cutting blades, filed it smooth, and screwed it to the cherry blank.

The next steps will be to cut the mortise for the vial, cut the blank to shape, add brass corners to the bottom, and mount the vial.

This is a very fun little project which should get some use in my shop. It would also make a nice gift for someone who likes shiny things.

Valentine's Day is just around the corner, after all.

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Thank you to the commenters who found some helpful links:
Machinists' center drill for starting screw holes in brass.
Slotted brass screws.
More slotted brass screws.
Thread about replacing level vials.
Level vials.

20 comments:

  1. Nice, Kari. Looks like your work will be plumb for years to come.

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  2. Very nice, however the phillips head screws are a bit out of place.
    Slotted iron screws with their slots all lined up.

    Stephen

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  3. Thanks, Dyami. :o)

    Stephen, that's correct. Not only would the look better, they'd be more period accurate.

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  4. Hi Kari,
    I can't wait to see the finished project. Had you thought of using round head brass screws and then sanding everything flat and even? Or do you need access via the phillip head screws?
    rjb37

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  5. Very impressive, you have a nice taste for tools

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  6. Ralph, I was going to try to find slotted brass screws eventually. The phillips head screws are temporary so I can keep working on the project. I'm not really sure how easy they are to find, though. They used slotted steel screws in the 19th century levels, but I thought that brass would look prettier.

    Thanks, Julio. :o)

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  7. Very nice. Can I ask what metal cutting blades you are using for the scroll saw? I was actually just thinking about getting some. I've used my bandsaw with regular quarter inch wood cutting blades to cut straight lines in brass, and it works just fine. It dulls the blade, obviously, but it beats a hacksaw.

    If you won't ever need to take the screws out of the brass plate, try using oversized screws, and when you file the head down the slot will disappear. You'll end up with what look more like rivets than screws.

    Also, try using a machinists' center drill for starting screw holes in brass. http://en.wikipedia.org/wiki/Drill_bit#Center_and_spotting_drill_bits

    You'll never have a bit skid around on you again. I can't wait to see more of this!

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  8. John, I bought blades from this guy:
    http://www.mikesworkshop.com/blades.htm
    Excellent service. I contacted him about his blades on a Saturday and he emailed me right back, so I placed an order. I had them by Tuesday.

    One of my antique levels was difficult to take apart because the brass had been trued one too many times so the slots were just about gone from the screws. They were almost down to rivets, as you pointed out.

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  9. Kari.

    These folks...

    http://www.leevalley.com/en/hardware/page.aspx?p=40960&cat=3,41306,41334

    (sorry that's not a proper link, you'll have to cut and paste)

    ...have an assortment of slotted brass screws. You probably have a host of other sources though. Just thought I'd pass it along. Lee Valley have a US location as well from which you could place your order.
    I'm sure your finished level will be stunning. I look forward to seeing it. Happy Valentine's Day.

    Best to you.

    Bob.

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  10. Kari...where do you find replacement vials? I have several old levels that require replacements.

    Thank you for your blog and I look forward to your next post. Mark

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  11. Very nice work, I really like the shape of the brass. What scroll saw did you get, and how do you like it so far?

    -Pete

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  12. Mark, my friend Charles Davis (Wood Zealot blog) sent the vials to me, which he found on ebay. I do not know another source for them. If you happen to find one, please let me know and I'll add it to the post.

    Pete, I got the DeWalt scroll saw and like it very well. I haven't tried any other saw other than a cheapie one, so I don't know how it compares to others. It has variable speed and tensioning, a big table, and a dust blower. I cut the brass very slowly on it, though, because I didn't want to break a blade. But it zips through wood quickly.

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  13. McMaster-Carr has every screw you can imagine. Here's a link the the slotted brass ones:

    http://www.mcmaster.com/#brass-wood-screws/=b195q6

    James

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  14. HI Kari,

    I was searching the web for replacement level vials and came across this thread on a machinist site.

    http://www.practicalmachinist.com/vb/general-archive/starrett-98-4-level-vial-replacement-83842/

    Check out John Gardner's set of instructions on replacing a vial on a Starrett Machinist Level.
    I found the topic most interesting.

    Thanx
    Village Sexton

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  15. Hi,

    This is probably obvious but I can't think of it: How do you make sure your level is level? If your vial is just barely off, your level will be off too. I imagine you can level against another level, but that defeats the purpose.

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  16. McMaster-Carr also sells level vials. Just search for "vial levels" from the home page and you get many choices.

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  17. James, Village Sexton, and Philip, thanks for the links. Awesome! I'll add them to the post.

    Anon, I was planning to find a level surface in my shop (table saw perhaps) by using another level. It might require shimming if I can't find a perfectly level surface. Then I was going to mount the vial as carefully as possible. If it's off by a little bit, I can plane the bottom of the level until the vial registers level. In Rosebrooks book and in the levels I bought, there are features you can add to make it adjustable, but it's a bit tricky. I'm just keeping it simple for my first one.

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  18. You can make or verify a level spot using water. Since water always seeks its own level...

    Over large distances, like a house foundation, use a garden hose with clear tubes at both ends. Fill the contraption with water until you can see the water level in both of the clear tubes. Regardless of the terrain, the water line in both ends mark the same level plane.

    For shorter distances, like a table saw top, use a clear pyrex cake pan. Measure equal marks on the four sides and fill with water. Shim until the water is equal to the four marks.

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  19. In "Restoring Antique Tools", Herbert Kean describes floating a plank in a bathtub of water to establish a true level reference. A slab of styrofoam would probably work just a well. The idea is that you do this once (or occasionally) to calibrate a "master level" which is then used as the standard to check other levels.

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