Reversing a HF Grinder (3 wire AC motor)

[MCW]

I wired my 511A to run both ways 3yrs ago. Works perfect. I've never had an issue with bolt coming loose but I make sure I get it fairly snug before I turn it on. The drill idea is pretty cool. I wish I'd thought of that instead of re-wiring mine. Oh well.....

The nuts backing off isn't a problem with the better quality grinders

 

[barneyrb]

Good job, what amp reversing switch did you use? I think it would need to be at least a 5 amp. Mine says 230 watts at 110vac which is 2.1 amps but I do like to "over engineer" some things. Do it once and forget about it.

Also make sure you never swap directions until the wheel has come to a complete stop. Don't just flip the reversing switch.......

 

[MCW]

Good job, what amp reversing switch did you use? I think it would need to be at least a 5 amp. Mine says 230 watts at 110vac which is 2.1 amps but I do like to "over engineer" some things. Do it once and forget about it.

Also make sure you never swap directions until the wheel has come to a complete stop. Don't just flip the reversing switch.......

The DPDT switch is only to reverse the starter circuit. It doesn't bare the whole current draw as the main switch remains.

And yeah, don't flip the switch while it's still running

 

[srcarr52]

Good job, what amp reversing switch did you use? I think it would need to be at least a 5 amp. Mine says 230 watts at 110vac which is 2.1 amps but I do like to "over engineer" some things. Do it once and forget about it.

Also make sure you never swap directions until the wheel has come to a complete stop. Don't just flip the reversing switch.......

The switch just reverses the starting windings so flipping the switch while running won't stop it while it's running... it will just kill about 1/3 it's power.

The starting windings don't pull that much as there is many more windings of smaller wire than the primaries. But the switch I used was overkill, 6 A at 125 VAC and was purchased for it's size. DPDT Flatted Metal Lever Toggle Switch : Toggle Switches | RadioShack.com

 

[lps8]

uninformed question

For the uninformed, what is the purpose of reversing the motor? Just asking.

Larry

 

[lps8]

just got informed

Found the answer to my question in another post.

Larry

 

[jerrycmorrow]

Found the answer to my question in another post.

Larry

so share the answer, or the post, or both already:msp_smile:

 

[dq72]

MCW In reguards to the nuts backing off, I'm talking about the bolt that holds the stone on motor.

 

[nstueve]

so share the answer, or the post, or both already:msp_smile:

It allows the grinder to cut both sides of the chain from the back of the tooth to the front then. I believe the idea is to run the wheel the same direction through the cutter in order to produce a more even grind. It also leaves small metal burrs on the outside of your cutters when you run the wheel from the front to the back of the cutter. Some say it does and some say it doesn't matter as far as cutting speed goes. I assume the burs fall off when the chain hits the wood and you're just fine either way. I think it's more for the "A.R." or picky people... anyone care to add/correct me???

 

[heimannm]

As noted, flipping the switch while it is running does not change the motor direction, in fact you have to let it come almost to a complete stop in order to change directions. There is not enough torque with either of the ones I have to loosen the screw that attaches the wheel, but I put a little blue lock tite on there anyway...

Also as noted elsewhere, if you spin the wheel fast enough in the opposite direction then switch the motor on, it will continue to run "backwards" but adding the switch makes it easier than grabbing the drill every other time you switch it on.

And for the sake of the old timers let's get this straight: DPDT means Double Pole, Double Throw.

SPST is Single Pole, Single Throw like a simple light switch, open or closed.

SPDT is Single Pole, Double Throw like the switch used in a three way circuit to switch lights off or on from two locations.

DPST is Double Pole, Single Throw, like two SPST switches side by side switching two lines at once, similar a 220 volt breaker in your panel for example.

DPDT is Double Pole, Double Throw like two SPDT switches side by side.

After that is gets complicated...

Mark

 

[heimannm]

...Heimanm started explaining to me how to do this to mine.......I heard, first you have to blah flop boop blah blah a huh

Same sort of explanation I got from Mitch when we were discussing porting..."open up the widenings then raise the lowers and boost the uppers then cut the squish into transfer intake exhausters and mod the muffler belt...

I had already taken care of the belt, thank you.

Mark

 

[Dan_IN_MN]

Great write up!

In my sig are other threads on how to tweak the grinder to get the best use out of it.