Author Archives: Patrick Fenner
Maker Faire UK 2013
This coming weekend, Maker Faire UK is at the Centre for Life in Newcastle. I’ll be exhibiting as part of the DoES Liverpool stall this year. While I initially started going to DoES Liverpool, it was to get some hands-on experience with running a laser cutter, which would improve the work I was doing with [...]
So What’s a Practical Laser-Cut Clip Size?
I’ve previously shown for laser-cut elastic-clips for comb joints what the equations are for calculating maximum bending stress and operating force, using the distance that the clip has to deflect in use as the starting point. I also explained how a tapering clip profile was preferable to a straight one. This time I’m going to [...]
Laser-Cut Elastic-Clipped Comb-Joints
During a makerday, I saw a someone struggling to put together a Raspberry Pi box that they’d laser cut, and were trying to hold together: two pieces of acrylic to make the joint, and the Raspberry Pi board, and a nut into a slot, while also attempting to screw in a bolt, and not drop [...]
Second Lattice Hinge Samples
As part of my first week as the new Technician-in-Residence at DoES Liverpool I’ve found time to photograph the acrylic test samples. From the earlier posts, this second set of samples is sized to have the minimum possible bend radius for single laser cut to create the torsional links, and has three torsional stress levels; [...]
Laser Cut Christmas Trees
I had half an hour at the end of the day at the DoES Liverpool makerspace the other day, so I had time to cut out christmas tree decoration from card and mdf that comes out of the cutter fully finished. The cut files are available for you below, or on Thingiverse, to cut your [...]
Lattice Hinged Booklets
I’m pleased to have created a first product using the lattice hinges: a laser engraved, hand printed A5 sketchbook for Red-Violet Made. They use a pair of lattice hinges gives a double fold that operates like a normal hard back book, with a flat spine instead of curved like other booklets. Using such a small [...]
Lattice Hinge Design — Choosing Torsional Stress
The first set of lattice hinge tests I generated were a little fragile, with the maximum stress in the torsional links set to be 60MPa (the yield stress of the acrylic) it’s not very surprising that, with acrylic being a very brittle material (where the ultimate/breaking stress is very close to the yield stress) that [...]
Lattice Hinge Design — Minimum Bend Radius
The last set of hinge tests that I showed used a cut out a rectangle of material to form the links. By re-arranging a formula that calculates the required inter-link clearance, it’s possible to find the minimum number of links to make a bend using only a single cut with the laser if the width [...]
Thin-Walled Structures Journal Paper
You might have noticed that posts have been thin on the ground for the last few weeks. Along with completing the revisions for my PhD thesis (which is now submitted), I’ve also completed a journal paper that has also gone for submission. This will be the second journal paper that I’ve submitted for peer review, [...]
Seat Reclining Bar
When I originally posted about the seat structure, I left the seat adjustment separate from the main seat structure design. I had the ideas about how to implement the adjuster, but it needed some time to let them mature into a practical design. The idea is to use the simplest adjustment mechanism possible. It needs [...]