[legolor] brings us a great, cheap rotary axis to add to your small 3 axis CNC mills. How are you going to generate G-Code for this 4th axis? That’s the great part, and the hack, that [legolor] really just swapped the Y axis for the rotation. To finish the workflow and keep things
cheap accessible to all there’s a great trick to “unwrap” your 3D model so your CAM software of choice thinks it’s still using a linear Y axis and keeps your existing workflow largely intact. While this requires an extra step in Blender to do the unwrapping, we love the way this hack changes as little of the rest of your process as possible. The Blender script might be useful for many other purposes too.
The results speak for themselves too! We thought the 3D printed parts were suspect in a CNC setup, but for the small scale of game pieces and milling wood, the setup is stable enough to produce a surprisingly accurate and detailed finish. If you want to try the same approach with something larger or a tougher material, [legolor] has a suggestion of a tailstock setup that’s still under $100 USD. Continue reading “This $12 CNC Rotary Axis Will Make Your Head Spin” →
Laser cutters are becoming more garage-accessible with overseas imports, but plenty of us still need to drop in on the college campus or makerspace to get our cuts. Having a laser onsite is a nice touch, but having a rotary axis is almost unheard of. These nifty add-ons enable your laser to cut and engrave radially symmetric parts. Their pricetags usually fall in the hundred-to-thousand dollar price range, so while that might stop us there’s nothing holding us back from building our own!
That’s exactly what both [Cesar] and [Russ] did with two homebrew designs built from scraps, and the results look comparable to the professional default. The design itself is simple, yet dead clever. The carriage straps directly onto the x-axis such that its motion is rigidly connected to it. The wheels on the bottom play a dual role. First, they let the carriage slide smoothly with the y-axis motion. They also support the object-to-be-engraved and convert the wheel rotation from the y-axis movement into rotation of the object. There’s one drawback here in that the diameter of the object-to-be-engraved affects the angle of rotation, but we’ve never been ashamed to do a little work with θ = s/r.
[Cesar] gets the credit for putting this hack out for the world to see, but [Russ] also get’s a big thanks for putting out a downloadable file of his carriage. It’s a testament to how sharing a thought can inspire us to iterate on better designs that they world can enjoy.
Rolling fourth-axes aren’t anything new on these pages, but they’re certainly rare! If your hungry for more rolling axis goodness, have a look at [Perry’s] router modifications.
Continue reading “Laser Rotary Adapter Gets You Rolling” →
Here’s a great CNC hack that adds a ton of functionality, a DIY rotary 4th axis!
[Jim] had started this project over a year ago when he originally ordered the gearhead off eBay, but like many good intentions, sometimes projects just get pushed to the back burner until necessity forces action. That necessity was entering our Trinket Contest, and he decided to finish it off just so he could put a HaD logo on a piece of PVC for us!
Unfortunately it took him a bit too long, and he only finished it last week — but luckily he had a fallback plan, and submitted his CNC Etch a Sketch project instead, which won him a Trinket anyway!
The 4th axis uses a 276oz-in stepper motor which is directly coupled to a Harmonic Drive Systems 11:1 planetary gearhead. It’s extremely accurate, has minimal backlash, and by using a 10 microstepping Gecko stepper drive, [Jim] is getting about 61 steps per degree of rotation. Not bad for a home-made setup!
Check out his blog for a great write up on the project, and stick around after the break to see the 4th axis in action.
Continue reading “DIY CNC Rotary 4th Axis” →