Thread: SmartHinge review

Boxmakers who want to make a box with a lid that opens just past vertical and stays that way have, until now, been pretty much limited to either side chains or quadrant hinges. To my mind, side chains are a clumsy solution, and the quality of quadrant hinges is variable. Even the good ones are fiddly to install, with the danger of popping the trench for the quadrant out the back of the box.

No doubt these thoughts were at the back of Andrew Crawford's mind when he collaborated with an Australian engineer (someone on these forums?) to create the SmartHinge, which is easily installed and works!

The hinges are only available by ordering from Andrew Crawford in the UK, but mine were actually posted in Australia. Because of high demand for the new hinges and problems with quality control, there was a delay in supply and Andrew offered to refund my payment, but I didn't cancel and the hinges arrived a few days later. Cost is £39.50 per pair, with a slight advantage in buying more than one pair.

The hinges are solid brass, polished but not lacquered. The finish is excellent and the arms properly aligned. The come with full fitting instructions which are also available on the website, and additional slotted screws are supplied.

Fitting is straightforward if you have a router table. It is easier if you keep an extra length of material from the sides of the box about 100mm long, for making test cuts. The hinges are 8mm wide, so the minimum thickness for the box sides is about 10mm.

The slots for the hinges are cut with a 5/16" (8mm) cutter. Andrew recommends a downcut spiral cutter, but I used a straight cutter with no problems. First, use a fence to align the cutter with the centre of the test piece. Make a spacer 34mm wide and use it to set a stop on the fence.
Then, progressively raise the cutter until the hinge sits flush but not below the top of the side. Make a test cut, and if it is satisfactory, cut one slot on the lid and one on the bottom. Then move the stop to the other side of the cutter, again at 34mm, and repeat.

When drilling the screw holes make sure that the screws will push the hinge arms to the end of the slots by marking the centres very slightly towards the front of the box, rather than dead centre. As always with brass screws, there is a danger of the screw breaking, but fortunately this didn't happen to me. If you are able to get the correct size steel screw to pre-thread the hole it's not a bad idea. Otherwise, apply a little candlewax to the threads before you screw them in.

These instructions are brief compared to the detailed ones supplied on Andrew's website. You should be fully conversant with his instructions before you start.

From now on, these are the hinges I will be using wherever I can.