Combination Square 45° Attachment


Another Inherited Tool

Letting you know from the start, this should be a pretty short post.  As the title suggests, it's about the restoration (really just a cleanup) of what amounts to just a part of a tool - the center-finding/45 degree head for my combination square.  This won't take long - let's get into it!


Much like a number of other tools I've restored, this one was from my former boss's grandfather, and come in one of these two toolboxes that were chock full of tools!

Though some earlier 19th century tools were called combination squares, the modern combination square was invented in the late 1870s by American inventor Laroy S. Starrett, and patented in 1879.  In 1880 he founded the L. S. Starrett Company in Athol, Massachusetts, United States. The tool was originally designed for machinists, but over time became commonly used in other trades, such as woodworking. - Robert W. Lang in Popular Woodworking

My Combo Square

I have no idea when I bought my combo square.  If I had to estimate, I'd guess it was about '98 or '99, and I have absolutely no idea where I got it.  But I've had it all these years and taken good care of it.  It was made by Empire Level Co., which I never really heard of before.  Nonetheless...

And although there are several different attachments (aka heads) for combo squares, mine only had the standard head.  It's the most basic of the attachments, but has a lot of versatility as described in Wikipedia, the standard head can be used as a:
  • Square, for marking and referencing 90° angles and checking if surfaces are flat and square to one another.
  • Miter square, for marking and referencing 45° angles, such as in woodworking for miter joints.
  • Spirit level, to check if a surface is level or similarly if a surface or edge is plumb (vertical).
  • Depth gauge or height gauge.
  • Form of marking gauge for marking lines parallel to an edge, by setting the head to a certain distance from the end of the rule.
  • Reference for directly transferring dimensions without needing to take a measurement, minimizing measurement errors and inaccuracies.
Although I always wanted some of the other heads (mostly because they looked cool), I never really needed any of them, so I was never willing to part with the cash.  But if one were given to me!

The Attachment

Like I said, I inherited this attachment, and was quite excited when I found it in one of the tool boxes.  The center-finder head can be used for:
  • Marking lines through the center of circular or square objects, such as dowels. Making multiple marks at different angles can be used to identify the point at the center of the circle.
  • Marking lines perpendicular to a curved edge (normal lines).
  • Bisecting square corners to mark a 45° angle.
When I got it, the head was in pretty decent shape with just a bit of surface rust, and some minor pitting in a non-essential area.  SO I soaked it in some rust remover, then sanded the appropriate surfaces to a nice shine.

After that, I just used some Testor's enamel to paint the old black surfaces and give it an essentially brand new appearance!

And et voilà - Done!

Like I said - this was going to be a short post!  This little project didn't take much, but it was fun.  On top of that - I now have another attachment for my square and - how cool is that?

And here's just a slightly closer look at the attachment!

And finally, here it is all together.  In actuality, you probably wouldn't use both heads on the ruler at the same time, but it looks cool like this!

Its Natural Habitat

Now that I have the 45 degree combo square attachment, I needed to find a spot to keep it.  I decided its new natural habitat would be in the measuring tool drawer in my restored Gerstner tool chest!

I know this was a short and simple post, and if you've made it to the end - thanks for stopping by.

See ya' next time!
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