This Fail of the Week post focuses on a project from [Limkpin] aka [Mathieu Stephan], one of the Hackaday contributors. He wanted a CNC mill of his very own and decided to go with a kit that you assemble yourself. If it had been clear sailing we wouldn’t be talking about it here. Unfortunately he was met with a multitude of fails during his adventure. We’ll cover the highlights below.
At the top of his post he lists the features he was looking for in a mill. He wanted something that had good community support, could be used for milling aluminum, and worked with tight precision. He settled on the Probotix Fireball V90. The kit is shipped from the US, and an international (shipping) incident caused the first fail. The front panel on the controller was bashed in, which in turn damaged the electronics on the circuit board. What’s worse is that it took several weeks to get replacement parts because of the insurance claim process with the shipping agent.
Next came problems with connecting parts — to us it sounds like the issue was with Probotix’s stock of screws. One was too large for the milled hole in a connector, and another was too short to use with the three others that made up the set. Once replacement parts were shipped [Limpkin] thought he was finally in business. He was wrong.
With the rig finally assembled he realized the Z-axis had some play in it due to the machined holes for the X-axis bearings. The video after the break shows a close-up of the issue. After receiving a replacement he started testing and realized there was an alignment issue with the Z-axis ball screw. Another clip below shows it misbehaving, resulting in a screech as the sled passes a certain point on the screw. It seems there was a bend somewhere that caused this. [Limpkin] did get around the issue by using a helicoidal coupler. This small success finally got his mill up and running.
So this Fail post actually ends in a successful CNC build running the sound-dampening box you see above. We thought about featuring this some time ago when it wasn’t working but [Limpkin] wanted to wait for the company to respond to his support requests. We’re glad we waited. The Fail of the Week series isn’t about trashing on creators of failed projects, so we don’t want to hear you bad-mouth Probotix. Instead we’d like to hear your stories about problems with your first CNC machine project. This example should drive home the message that whether you buy a kit or build from scratch, you need to be ready to deal with adversity the first time around.

Fail of the Week is a Hackaday column which runs every Wednesday. Help keep the fun rolling by writing about your past failures and sending us a link to the story – or sending in links to fail write ups you find in your Internet travels.

Filed under: cnc hacks, Hackaday Columns