It’s been a little while since I had a chance to catch one of John Grimsmo’s Knifemaking Tuesday videos, but this one caught my eye when it came through recently. It basically shows the Grimsmo brothers using their Tormach PSG 612 surface grinder on some sheet titanium that they’re preparing to be made into knife parts. What attracted me was the chance to see the PSG in action. It’s a neat little machine. Surface Grinders are extremely handy to have around, but unless you buy a much more expensive automatic surface grinder, they’re pure drudgery to use. The problem is they take off very little material with each pass, and you have to handwheel the thing to make the multiple passes needed to cover the surface being ground in X, Y, and Z. It winds up being a lot of passes if any appreciable material is to be removed!
Tormach came up with the clever idea of applying relatively inexpensive commodity automation to what had been a manual surface grinder to take the drudgery out of it, and they managed to do so for a very reasonable price–$3989 as I write this. That’s about $2000 for the automation versus a similar grinder that’s manual, but it won’t take very long to make that back in labor savings if you value your time at all.
The Grimsmo brothers are using theirs mostly for finish and to take a little warp out of the titanium sheet so it’s flat. They’re also using the belt sanding accessory, though the grinder comes with the typical wheels to start. Check out the video below. John’s videos are almost always good fun to watch:
[youtube]http://www.youtube.com/watch?v=5pPYgZ0lB1g[/youtube]
The automation involved is not all that complex, as you can see. They simply put toothed belt pulleys inboard of the handwheels and drive them with stepper motors. I’m sure some simple programming of Mach3’s Basic Scripting facility handles the programming end of it. If you’ve already got a surface ginder you’re happy with but wish was automated, it might make a good slack time project to try a conversion.
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Bob is responsible for the development and implementation of the popular G-Wizard CNC Software. Bob is also the founder of CNCCookbook, the largest CNC-related blog on the Internet.