on page 11 is a drawing for an adjustable spider gauge
http://www.fs.fed.us/t-d/pubs/pdfpubs/pdf05232815/pdf05232815dpi300.pdf

Yours looks to be a gauge that works from one side of the saw but can 
check the set for all the teeth.

On 10/8/2012 10:16 PM, Micheal McEvoy wrote:
> I seem to have run into a wall on this one.
> So far every one that I have asked has never seen a spider like this.
> I work as a seasonal with the Forest Service (Kawishiwi District Superior NF)
> and have asked just about everyone who works in the Wilderness Shop about it
> and no one has a clue.  I have asked at The Axe Hole, and they haven't seen
one
> like it either.
>
> The only marks on the spider are on either side of the hump, BT&R or BT&H on
> one side and HMB 2 on the other.
>
> Here's the url to the picture: http://tinyurl.com/8wyvbu4
>
> It's in the upper right corner.
>
>
> Thanks once again,
> Micheal

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