2x72 motor advice

Again I don't currently have access 220v. So it would have to be fixed speed if I want 2 HP. I can't get a 2 HP capable VFD that will run on 110v. So the 2hp 1 phase will go into a disk sander when I move to the shop that has 220v. The grinder then gets a VFD and 2-3 HP 3 phase motor. Can I get a sanity check on this?
 
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You're going to want variable speed on that disc grinder as well. I would sell that motor when you get the vfd and buy another 3 phase motor. Thats what I did. You'll be glad you got it.

I'm still learning on mine and haven't gone full speed yet.
 
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kdogmcg said:
Again I don't currently have access 220v. So it would have to be fixed speed if I want 2 HP. I can't get a 2 HP capable VFD that will run on 110v. So the 2hp 1 phase will go into a disk sander when I move to the shop that has 220v. The grinder then gets a VFD and 2-3 HP 3 phase motor. Can I get a sanity check on this?
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I misspoke. It's 1.5 HP. Link is above
 
I'm just meaning that if you're going to be using it to speed up your finish sanding process, 1800 may be tough to keep the blade cool.
 
I don't think that will be an issue. I currently use a 1x30 with a belt speed of 3260. The new grinder will have a belt speed of 2300 with a belt that's over twice as long.
 
2300 SFPM will be just fine for rough grinding. Even the start of bevels perhaps. OR - you might be an expert grinder who can handle that fast belt speed. Of course you're not planning on any belt finer than 80 grit? 2300 SFPM is starting to get pretty fast for 120 grit belts, for sure anything above that. Not even experts use those fast speeds on fine grit belts if they have a choice.

Now, with those "big" words spoken (written), I would love to hear from some of the "real" experts on here about how fast belt speed they use for 400 grit, and 320 grit. I am NOT an expert by any means.

Ken H>
 
I did this on my Harbor Freight 1x30 that has a belt speed 900 sfpm faster. I went up to 220 on the flats and finished by hand. I am by no means a seasoned maker. This is my 6th knife.
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Kdog, i was speaking of the disc grinder, not the belt grinder. My advice was once you get the vfd, instead of using a full speed motor for the disc, to sell the single phase motor and tie another 3 phase motor into your vfd so you'll have variable speed on both.
 
greenjebadiah said:
Kdog, i was speaking of the disc grinder, not the belt grinder. My advice was once you get the vfd, instead of using a full speed motor for the disc, to sell the single phase motor and tie another 3 phase motor into your vfd so you'll have variable speed on both.
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I figured that's what you meant. You think 1800 rpm is too fast for a 9" disk sander?
 
I have just recently started using the disc to go up into the finer grits and i go pretty slow, maybe 25-50% on an 1800 rpm motor. Maybe the pros go alot faster. I just don't want to jack up the heat treat.
 
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