Bed sparking protection and logging

In a previous post I described some safety electronics for Squirty the RepRap that will switch off power to the printer if the hotend got too hot or if the bed was powered for too long. In this post I’ll describe an upgrade to that system and a setup to allow logging of safety information […]

Multi Setting Calibration Prints

3D printing is, of course, the most frustrating hobby in all existence. Browse through any 3D printing forum and alongside the beautiful prints you’ll come across posts that compress incandescent rage into a few choice words like “I’m throwing my ******* printer out the window”. In my case most of this rage comes down to […]

3D Printer Safety Cutoff

In this post I’ll describe a safety system I’ve put together for Squirty the RepRap that should prevent the type of catastrophic thermal runaway that I experienced a few weeks ago. The system could work for any printer with a little modification (but obviously use at your own risk!).

Unmelting a printer

After my printer almost killed me I needed to get my hands on a new hotend. RepRapPro, which made my printer kit, has unfortunately closed down so I got a new nozzle, heater block, heatsink block, heater cartridge and thermistor from The nozzle is the new “quickset” design, which is clamped in place rather […]


After a period of relevant dormancy, Squirty has had a lot of work done recently. I have replaced most of the original plastic parts, which were starting to crack, and put in new bearings. I also designed a new x-carriage ducted fan adaptor that put better air flow on the printed part and put in […]

Measuring a 3D Printer Bed’s Flatness

Once I got my printer’s z-probe and autoleveling set up I was struck with a sudden paranoia that my printer bed was saddled. The standard autoleveling in Marlin can deal with a printer bed that is not level, but it cannot fully correct for a bed that is not entirely planar*, e.g. one that is […]

Melzi holder and new wiring

In the last couple of posts I described how I put a z-probe onto Squirty the RepRap. Adding the z-probe meant new wires. These wires ended up jumbled all over the place and occasionally got caught on the z-axis threaded rods, causing all manner of chaos to break out. The z-probe also requires a lot […]

Z-probe V2: Autoleveling

Following on from the previous post I redesigned the z-probe holder to position the microswitch closer to the nozzle. I also forked the latest version of the Marlin firmware to correct some problems I was having with the leveling behaviour. The video below shows that the autoleveling seems to be working, but I need to […]

Z-probe V1: The Gom Jabbar

By far the most frustrating part of 3D printing with Squirty the RepRap has always been the strange dance you have to do to get the Z distance correct. I use a strip of paper and carefully pull it back and forth underneath the nozzle while trying to bring it close enough to the bed […]

Ducted Fan Part II and Octoprint

Last month I posted about installing a ducted fan on Squirty. After installing the fan I read issue 42 of MAKE magazine and became excited about two ideas to try for testing out the ducted fan. As is often the case, I got a bit distracted trying out these ideas so it’s taken me a […]