Editor’s be aware: William Howes’s Ames sq. is likely one of the shop-made instruments featured in our gallery for Instruments & Outlets 2022. Right here, he particulars how he made it.
Nathan Ames of Boston was issued a patent in 1852 for a sq. that might be used to seek out the middle of a circle, a great tool in setup for spindle turning on the lathe. This ingenious device was manufactured by J.R.Brown and Sharp of Windfall, R. I., and is typically nonetheless accessible in outdated device markets. Ames held different patents together with one for a precursor of the escalator.
In addition to discovering the middle of the inventory, it may also be utilized in a trend like a contemporary velocity sq. to structure 90° and 45° angles and to examine inside corners for squares. I made a decision to breed this enticing device in wooden.
Creating a duplicate in wooden requires cautious work, and after a number of makes an attempt, I concluded that using easy jigs would enhance accuracy.
Begin by milling inventory to five/8 in. by 5/8 in. Any fine-grained hardwood is appropriate, I’ve used apple, hawthorn, and beech, however something accessible will work.
Be a part of the sq. sides with a butt joint held by a screw (1 in.#6). A jig to carry the items at 90° is helpful.
Alternately, a half lap joint entails no screw, and if the glue-up is true the joint stays sq., in distinction to the butt joint.
The bottom or hypotenuse of the triangle joins the 2 equal sides with half-lap joints. Lay these out to a depth of half the thickness of the ruler. I made my rule 1/4 in. thick, and the lap joint mortises every 1/8 in. deep. The blue tape helps with the accuracy.
And a flush-cut noticed with no set permits the wonderful lower.
Once more, a jig to carry the whole lot sq. throughout glue-up simplified issues.
Setting the ruler in.
A small scrap lower to 45° aids in laying out the mortise for the ruler. Measure from each edges and go away the road, as this would be the future heart line that you find yourself drawing while you use the device.
Take care with the structure, ensuring that the ruler is to the left of the midline, if you’re right-handed.
Remembering that this view is of the underside of the sq., make the inset for the ruler a hair undersize in order that adjustment might be made to permit the ruler to be 90° to the baseline.
Earlier than gluing up, it’s simpler to melt the perimeters and corners.
The completed product.