I’ll never get tired of the innovative and fun ways that makers and tinkerers find to put a good 3D printer to use. We’ve seen how 3D printing has altered dozens of industries as diverse as the automotive industry, the jewelry industry, medical and dental and even Hollywood special effects. But it has probably had an even more profound impact on makers by giving them the means to build virtually anything that they want both cheaply and quickly. Especially when what they want to build probably is something that they really only need for their own projects and isn’t going to end up on Kickstarter any time soon.
When engineer and maker Bruno Martini began formulating plans to build his own CNC mill he knew that he would need a machine that would provide him with some extremely precise cuts, especially for many of the metal parts that he would need to build a sturdy mill. But being a maker meant that any piece of equipment that he would need to buy would be priced far out of his reach. Like any maker worth his salt, he decided to see if he could build a machine that would get the job done without breaking his wallet. So Martini turned a hacksaw, a cheap DC motor, a discarded IKEA table leg and some 3D printed parts into a functional power hacksaw.
Martini’s hacksaw started in SketchUp where he designed the 3D printable parts that he would need and the basic design of the hacksaw. While the initial design took him about two hours, he needed to tweak the parts a few times to get everything working correctly. He decided to use a geared DC motor to run the hacksaw, but he was careful to use one that wouldn’t move the saw too quickly so he could avoid the blade heating up and breaking. While he has used basic hacksaw blades for his tests he will be upgrading to metal-cutting blades when he begins using the saw to build his CNC mill. And yes, you read that correctly, he did use the leg of an old IKEA table in his design; in this case he bolted the hacksaw itself to the leg to give it support and stability.
Despite the odd collection of components, Martini wasn’t just building this for fun; he really needed it to work and to work well. In order to give the power hacksaw more durability he 3D printed the parts on his custom built delta-style 3D printer using ABS so they would hold up to repeated use. To make sure that the parts were strong enough to support the working mechanism he printed most of them, including the crank, the caps that held everything in place and the main rod that drove the saw, with a 100% infill so they would be extremely hard to break.
Just reading about the hacksaw isn’t enough, you actually have to see it in action:
As you can see, the hacksaw works great and while it clearly isn’t built for speed, speed wasn’t really a priority for Martini. He was more interested in avoiding having to buy expensive industrial equipment and eliminating the physical labor of needing to cut the metal parts on his own, and his power hacksaw does both. It may take a while to cut through metal, but it leaves an extremely smooth finish that won’t need to be filed or smoothed at all, as it would have if he had hand cut all of the parts.
“As an engineer, I can speak that there is only one universal truth, there is no 100% no compromise solution. Every solution has compromises. The trick is to make the right compromises to deliver the best possible solution,” Martini told me via email.
You can see Martini successfully testing his hacksaw on a steel bolt here:
Overall Martini was quite pleased with his power hacksaw build, saying that his first try even came out better than he had hoped it would. He is still going to be tweaking it before he puts it to work cutting metal parts for his CNC mill, however. He is going to add some clamps to his device so it can be locked down on his work table. He is also trying to add some pretension to the arm so it will run more smoothly and add more stability to the blade. And since the hacksaw will be working independently, Martini is also developing a way to get the saw to auto stop after the cut is complete.
Of course Martini’s power hacksaw is still just an experimental work in progress, but he has shared the project online so anyone can try to build their own. He’s uploaded the 3D printable files to YouMagine for download and included a full list of parts and supplies on his blog. You can also find more of his videos and projects on his Engineerd3d YouTube channel. Is this something you’ve thought of making? Discuss in the 3D Printed hacksaw forum over at 3DPB.com.