More on the ThumbNail

Here is a third application, reminiscent of the Silva 66 which is no longer sold in the US. Perhaps a choice for those using ski or hiking pole.

James mentioned that the Thumbnail is not recommended for taking bearings. With later colorwheel version you can get a rough bearing. The needle indicates the direction of travel to within 10 degrees or so. For example, above shows due east and below shows ENE.

-Joe

Alex Finch said...
Joe sent me a prototype of his new Thumbnail compass, and I love it. The minimal design is exactly what I want from a compass here in the Bay Area.

I bought a Spectra Nexus a year ago. Slipped at Bon Tempe in December. Went to use my compass a short while later and all that was attached to my thumb was a piece of the thumb plate. Went back to find the broken pieces of the compass. I must have broken my fall with my hand without realizing it.

The Thumbnail with a single strap sits nicely on the back of my thumb at the base. Close enough to the map to orient it. Yet my thumb is completely free to mark my spot. In fact my whole hand is completely free to grab anything. And the compass is always right there when I need it.The colorwheel allows taking rough bearings or quickly heading out in the right direction. This is more than adequate for the orienteering we have in the Bay Area.If I were to travel out of the area, I would probably bring a baseplate along as a backup in case I encountered a situation that required accurate bearings and/or pace counting.
10:18 1/1/09

On March 15, 2009 Alex added:
Joe,
Finally got a good run in with the compass. It was great. I even took an identical fall to the one I did at Bon Tempe where my feet slid out in front of me and I put my hands down to catch me. Bon Tempe = broken thumb compass. Briones = good thumbnail. The ink on the paper colorwheel you had installed ran from my sweat or the general moisture. I just replaced it with the laminated one you gave me. I'll see how that holds up at the goat.
-- Alex

Hi Alex-
Glad you like the compass and thanks for serving as a crash test dummy. As I recall, the laminated color wheel with your test unit was cut after lamination so the paper is not sealed around the edge. Please give it a good test to see if it is OK. In the future I will probably cut out the paper before laminating.
-Joe

Toby Ferguson sent an e-mail on May 18, 2009 as follows with my reply:

The thumbnail compass works great for me. I like it because it is EXACTLY where it needs to be for me to orient my map. I find that I orient my map faster and more accurately most of the time. Very occasionally I've wished for a baseplate so I could measure distances and get very accurate bearings (that would've helped me on a couple of the long legs at Bogg's, I think), but so far the compass has proved very valuable. One area I'd like to see improved, and that is to make the base card more waterproof. Mine is starting to get streaky and the colors are beginning to run a little (mainly from sweat, I think - Bogg's didnt' seem to affect it much). But of course the needle still points North, and that's all that's really needed! I am confident that I won't break the compass, and that it will stay secured to my thumb. It's so small and lightweight that I quite forget I'm wearing it when I'm "running with the front legs" as Tapio Karras calls it (a steep climb through dense undergrowth!), which is how it should be!
Toby

Hi Toby-
Thanks for the write-up. Your prototype had plain paper or if laminated was not sealed around the edges. (See Alex’s comments.) As production gears up I will have sealed colorwheels. They are easy to replace.

I also have some ideas for a scale. My personal solution is to carry a good baseplate compass in my right hand for distance measurements and precise bearings.
-Joe