(Re)Produce Accurate Arcs
By Benjamen Johnson
Sometimes you can make a serviceable arc with just a couple of nails and a thin piece of wood, but what if you need to exactly replicate an arc or produce an arc of a known radius? You break out Hoyle’s Acu-Arc adjustable ruler.
The Acu-Arc ruler lets you determine the radius of existing curves, produce arcs of a known radius, and find center points of curves and center lines. You can adjust the 12″ flexible edge to reproduce curves with a 6-3/4″ to 200″ radius, or a 17cm to 500cm radius in the metric model. A sliding knob locks the curve in place, and a handy scale lets you read or set the radius of the arc.
Hoyle makes the Acu-Arc ruler with plastic that’s rugged enough to stand up to everyday use, but it apparently bursts into flames or something when hit by direct sunlight, according to the manufacturer’s all-caps warning: “KEEP YOUR ACU-ARC RULER AWAY FROM DIRECT SUNLIGHT!”
The Acu-Arc adjustable ruler runs between $35 and $50.
Acu-Arc Adjustable Ruler [Hoyle]
Street Pricing [Google Products]
Via Amazon [What’s This?]
October 30th, 2008 at 12:23 pm
Maybe it’s really the acu-arc of the covenant and exposing it to light releases the spirits who will attack you?
October 30th, 2008 at 3:18 pm
Wow, 17mm? I’d get the metric version, the Imperial one only goes down to 17cm.
October 30th, 2008 at 3:37 pm
Oops, my bad. That should read 17cm.
Damn Metric…
October 30th, 2008 at 5:08 pm
I might find this useful for bending pipe, been looking for something like this.
It’s probably made of PVC and expands in sunlight.
October 30th, 2008 at 5:29 pm
I suspect that the plastic it is made from has no or limited UV stabilizer built in - so it would get brittle.
October 30th, 2008 at 6:17 pm
Its actually a drafting tool and I’ve had one since the early 70’s and it still functions fine, though I don’t use it much anymore since I converted to CAD in the early 90’s.
$35-50 huh? I think I paid about $15 way back when and thought that was alot!
Oh the times they are a changin’………
November 5th, 2008 at 6:27 pm
I’ve been doing archtectural drafting for decades, and this tool comes in very handy, once-in-a-while.
The ony problem is that it can be a bit delicate: if you look at the part of the plastic that actually bends, you’ll see that it is rather thin. So this valuable tool needs to be treated with respect and care.