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Author Topic: Spindle FWD/REV Question  (Read 1718 times)

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Spindle FWD/REV Question
« on: August 11, 2016, 07:21:15 PM »
Hi everyone,

Working on some mods to my control box on a 6040Z (Chinese router style mill) and have a question or two for ya.  My mods started as a simple task of making the VFD controllable through software instead of the front panel controls.  Well, this turned into a bigger project where I can now switch between panel control and Mach3 control through a couple of front panel switches, one for speed and one for start/stop/program control.  I've also added a coolant system and put the components in the control box so that it is an all-in-one control center.

The question is:  can anyone tell me why you would want to run the spindle in reverse (i.e. M4 vs. M3)?  The reason I ask is that would add some complexity to how I'm wiring it all up and since I've configured Mach3 to run the same relay for M3 AND M4 it will only run in FWD as it is right now.  But if there's a significant reason I would want to run it in REV, then I'd need to modify the design (mod the mod, lol) to work for both directions.  I have an available relay on the BOB and indeed have previously had it wired in and working for ture FWD/REV control.  However, I never saw a need to run reverse so I removed that from the equation and this also made my external/panel switching simpler.  So again, is there a real need to run a spindle in reverse?  To me that just seems unnecessary and possibly even dangerous.

Let me know your thoughts,

Stephen "Highspeed" Kruse

Offline ger21

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Re: Spindle FWD/REV Question
« Reply #1 on: August 11, 2016, 08:37:04 PM »
On a router, you only need to run a spindle in reverse if you want to use left hand router bits.
They can be handy in some case when tearout can be a problem with a right hand bit.
They are generally only used for specialized applications. Also note that left hand router bits cost about 50% more than an equivalent right hand bit.

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Re: Spindle FWD/REV Question
« Reply #2 on: August 11, 2016, 11:05:18 PM »
Awesome info.  Thanks Gerry.  I had considered that possibility, but wasn't even sure if that type of bit existed.  (This is where my relative newb-ness shows through.)  So it sounds like I would be pretty safe designing it for single direction (CW/FWD) control and leave it at that.

Thanks for the quick reply.