Rotation direction for belt sander sharpening

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Using a tool rest with plane irons and chisels, my intuition is to have the belt running away from rather than into the edge - so the blade can't dig in. Same thing for sharpening knives freehand. If this isn't the case, how does one reverse the direction of an AC motor? Just reverse hot and neutral?
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You are correct that the belt should turn away from the edge that you are sharpening.

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Think about this for a moment. In school, I was taught to sharpen plane irons on a grinder and the wheel was always turning INTO the work. Wouldn't the same logic apply to a belt sander?
You cannot reverse the direction of an AC motor by reversing the leads.

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Think about this. The wheel provided you natural protection against a dig-in, because it was round, and you were sharpening at a tangent. The belt is flat. Not a good practice.
Depending on the motor, you might find instructions to reverse it, but the fractional HP types are less likely than the bigger ones to have this feature.
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Check any machine shop in the country. Belt sanders rotate the same way as grinders, into the cutting edge. I, and everyone I work with, have been doing it this way for as long as I have been around. Extremely rare to see a damaged belt. To reverse rotation would require a custom tool and, in any case, OSHA would have a cow.

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I have never had a problem when using a tool rest and the belt running towards the too. that's even with a 1/2" gap between rest and belt. even free hand the only problems I have are letting the tool slip sideways or down and getting my finger. I don't ever remember steel getting caught by the belt and causing a problem. I have sharpened and ground many blades this way over 3000 of them.
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You can't hear it, but I'm applauding.
However, it's the mind, not the hand which is required here. The statement is true, it's just not the way you do things. Anything which makes the belt less than flat (even inadequate tension) can take the piece away at worst, ruin the edge at best if it is running toward you. Not to mention the hot sparks flaming your hands unnecessarily.
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well that could be true but if the belt does not have enough tension your going to have a bad grind anyway. I have a hardened steel plate behind the belt where the blade hits. it stretches the belt tight too. the sparks usually hit your belly (G) once I set my apron on fire (G) atleast burned a hole in it. but that happens when the belt is getting dull.
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In case you hadn't noticed, the unit he referenced has a light-duty table, a platen which rarely reaches the belt, and a spring tensioner. All are disasters in waiting if he uses it toward the edge, tolerable if away. Oh yes, on a narrow belt it's easier to run off the edge, too.
Now let's rethink the wheels - honing is better in the opposite direction.
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Not to mention the hot

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Most of us stand in _front_ of the tool, not over it. Perhaps you should try it.
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That's probably why you have so much problem. Try getting close enough so you can see what you are doing.

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Well think about this Chuck. The OP is talking about a sanding belt. The sanding belt will cut very easily as opposed to a hard grinding wheel that will gouge at worst. FWIW the wheel spins in to the cutting edge of my Tormek when sharpening chisels, turning tools or plane blades.
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beep wrong driving the tool into the rest is the way to go. thousands of plane irons can't be wrong (G) if the belt is going away it would tend to pull the tool away and change the angle.
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Steve Knight wrote: >

Like climb-cutting with a router - requiring extra care if you absolutely must do it. I'll look into an asbestos apron.
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(G) the thing is you get more sparks with a duller belt. they seem to be hotter too.
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OK OK Ok ok ok ok ok... Goes against the way of my thinking but I trust your comments. :~) I thought it would surely make the cutting edge cut into the belt.
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If this is not a troll, the answer is to simply turn the belt sander 180 degrees.
-j

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J wrote:

I hope I could have made it more interesting if it was ;-). I should have mentioned that I was talking about one of these: http://www.leevalley.com/wood/page.aspx?c=2&pD884&cat=1,43072 which suggests a motor turning in a 'counterclockwise' direction - but as viewed from over the motor or straight at the shaft? (Pardon my mechanical ignorance.) As you can see, you can't really turn the whole grinder. Re. the rotation of grinding wheels, I don't see how the arc of the wheel is any protection against dig-in. The back of the blade is still going to be ground away at some point and this is where dig-in would occur... I guess the idea is that the force on the tool created by friction with the abrasive is directed toward the tool rest so the tool doesn't threaten to pull up. The abrasives must be uniform enough that you won't get a lump of something coming along to dig in to.
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Must be something I'm missing here. If you're going to buy the motor separately, just buy one which reverses. Or is there another question hidden somewhere?
Yes, you _can_ screw up with a grinder, but you'd really have to be ignorant. Something like setting the rest two inches away so you could dig in if you let go. Doesn't take much to tip the edge if you're using a belt.
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