Getting Started

Tuesday, September 6, 2016

A Square Jig for Square Boats

Holes range from 1/4in to 1/2in
May add 7/8in and 3/4in, someday


We meet upon the level, and part upon the square.
 -- Masonic Proverb
 
A Square Jig for Square Boats

Can't say I'm a jig kindofa guy.

When building TRILOBYTE on the fly, a friend stopped by to see how we were doing. He's an ex-shopteacher/current bowyer... standards are high. 

The task at hand was drilling the side windows for screws all around their perimeters.

Our usual approach is divide-and-conquer. This case was an eight foot stretch and we wanted fasteners every six inches or so. Open spaces are divided by twos or threes as seems right by eye. If we're feeling persnickety, we might measure and mark it, using a chip of wood to inset it. But we don't often.

Eight, four, two, one, half-a-foot. Shazaam.

This was a little too quick and dirty for our friend. He gave us a passionate speech on the virtues of precise patterns - how it was the mark of a professional. That it went quickly and looked its best.

We hemmed. We hawed. To show us how easy and efficient it all is, he volunteered to make us a jig.

He did, too. A nice li'l number that worked like a charm. A rabbeted slide with guide holes precisely placed. A thing of beauty, form and efficiency.

Problem is, by the time it was done - a matter of a half hour or so - we'd already drilled AND mounted all the windows.

Looked fine, too. Even he admitted it.

*****

One more story...

When computer generated music first came out, it sounded flat. Robotic. Lifeless.

Why? The algorithms were perfect! Every note was precisely on pitch. Sounded for exactly the duration specified. Attack, reverb and fade were mathematically true to the nth decimal place.

Sucked.

Turns out, the human ear doesn't care for too much perfection. Finds it sterile and uninteresting. Got no soul. Turns out, introducing small errors of pitch, tone and timing brought it alive to us. Turns out, we prefer our imperfect, gritty, wonderful world with all its flaws. We insist on them.

I'm sure there's a lesson in there, somewhere.

*****

So I'm not a jig guy.

But one thing that does come in handy in a square boat is a hole bored square to a surface. Not only handy, but if it's not square, often enough it's gotta be plugged and drilled again. Otherwise a fastner might not pass through its hole in a metal plate. Or a fastner head, washer or nut won't sit flat and water intrudes. Or the durn thing comes out the side.

A square jig for a square boat helps us along.

Next time you're near a drill press, I recommend this:

Start with  a nice, rectangular chunk of stock - hardwood or aluminum work easily and hold up.

Inset a line of squared off holes of standard sizes along edges - just enough room for your drills when pressed against a wall.

To use, align a face of the jig with the reference face to which your hole will be square or parallel. Run your drill through, or at least far enough to continue square without the jig.

Unless the jig is clamped (seldom necessary), I find it helps to withdraw the jig with the bit, rather than the bit alone. If you get off line withdrawing a running power drill while still in the jig, it can get jumpy.

It helps if the jig is big enough to clamp a bit of stock to faces as a guide if a necessary to reach a reference face. For example, when drilling bolts for the handrails (whose upper face had been rounded) we used their sides as reference and drilled parallel to that face and square to the run of the upper face.

This jig - with some extra long bits - has given us quick and easy square holes, every time we've needed it.

Guess it's alright.


Anke drilling with our first, 1/4in jig
Note board clamped to side as guide along handrail sides
for square, plumb and level


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