Do any of you guys know if it would be possible to install a variable frequency drive (VFD) on this grinder? Right now I run it off a standard 110 volt house plug, but it only has one speed - fast. I'd like to be able to slow it down for certain knifemaking operations. This is a Roy Wirtanen built grinder. Here's the label on the motor.... And here's the label on the power switch mechanism.... It's a great grinder and it's done well by me, but if I could run it slower at times, it would be a lot more versatile. Any and all advice is welcome, but keep in mind that I'm so dumb when it comes to anything electrical that I couldn't even keep up with "Electrical Wiring for Dummies"! Jim T
depending on what VFD you chose Jim , you made need a 3 phase motor...........one of my grinders is one speed 3450 +/- and I prefer the hoggin speed myself
Hi Jim, You'll need a 3 phase motor if using a VFD. <edit> There are some unusual ways of slowing down a single phase motor, but these generally cause heating issues. Some step pulleys are your best bet, but that is looking like a fundamental re-work of the machine. </edit> Dan
There are inexpensive VFDs that operate on single phase 120 power. They produce three phase, 240 VAC output. They are easy to use but most single phase motors are not amenable to variable speed due to starting mechanisms so 3 phase is recemended.
If you are considering buying the VFD don't let the motor change scare you away. You can get a new motor for a little over $100. I was looking at my lathe the other day and was thinking about how nice it would be to get another motor and VFD like I have on my grinder and fit it on the lathe. Hmm. It would look good on my drill press too. As you can tell I don't like changing belts. Lol.
Drat! I was afraid I might have to switch out motors. Thanks for all the feedback, guys. Rob, I'll dig a little further and find out what it will take to hook up a 3 phase motor. Dan, I agree with you, I think I'll have to look at an overall rework rather than a pulley system. Like I said, it's a great grinder and I wouldn't want to discombooberate it by over-complicating its present setup. And you're right, Icho. I can't let myself be intimidated by switching out a motor. Again guys, thanks! Jim T
Three phase motor and a VFD is the best and really only way. As far as switching to a 3 phase motor, as long as the mounting face is the same bolt pattern it should just bolt right up where the old motor came off. It would be more expensive than step pulleys but also less fab work to change the way the grinder is built.
Yeah Brandon, I have a hard time wrapping my head around any sort of modifications needed to set up a step pulley system. I think a 3-phase motor and a VFD is still the best option for me. Thanks for the input. Jim T
