In wanting to automate this grinder exactly how many axis do you want to control. I can see the movement of the table back and forth at that 1 RPM. I can see the cross slide at the end of each pass or pass and return? Finally I guess depth might also be desired to a total depth?
If depth was adjusted manually then my ELS can be configured to do something like this: http://www.autoartisans.com/ELS/ I'd set it up to turn the Z axis for BEGIN, END positions to move the table in the X axis directions. I'd set the X axis for the 'depth' of each pass so it would move the table across using some of the parameters to fool it into not retracting but either moving further in for the pass in the other direction or moving the stone out of the way for the return. But then that's just as easy with some simple G-Code and one of those far east CNC control boxes like this: https://www.aliexpress.com/item/1005003646128482.html For $140 Cdn with free shipping it's almost worth the risk to buy it and try it. You need stepper motor drivers, power supply, motors and pulleys anyway. > -----Original Message----- > From: Martin Dobbins [mailto:tu...@hotmail.com] > Sent: February-04-22 10:47 AM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] What Would You Suggest? > > Hi Kenneth, > > I don't know if this will be any use to you at all, and it's not Linuxcnc at > least not yet. > > I an effort to emulate this: > > https://www.youtube.com/watch?v=z4t8pmsnYow > > Which is all powered by a PIC > > I liked this but didn't want to use a PIC. Tried first with an Arduino > because I had one on hand, but that just wasn't going to work. > So, I moved to one of these and got the 3.2 version: > > https://www.pjrc.com/teensy/ > > Partly because it has an excellent library for controlling steppers: > > https://luni64.github.io/TeensyStep/ > > It's driving a NEMA 34 1805 oz/in through one of these > > http://www.leadshine.com/uploadfile/down/ma860hm.pdf > > which will work with AC or DC > > So, one of these: > > https://www.ebay.com/itm/194282558090 > > On the back of which is a jumper to set input voltage 240, 220, 200, 110. > With outputs on the back for 110v and 220v. It's intended > to be a travel item so your 110 volt stuff will work on 220v and vice versa. > A step up step down transformer. If you lie to it you can > feed it 118v to 120v (what comes out of my wall sockets) and get it to supply > lesser AC volts to the stepper driver. > > If you're still awake? > > I can get 2000 rpm plus out of that big stepper, but I don't need speed like > that, I need torque, so it's geared down 4:1 with the > spindle it's driving (when the stepper's rotating at a leisurely 25 rpm the > spindle is turning at 100 rpm). It's still an unfinished project. > > I'm envious of that grinder. > > Martin > > ________________________________ > Kenneth Lerman wrote: > > > Chris -- At my house, computers are all over the place. I think I have a > spare atom floating around. Also a couple of other machines. > Gene -- The grinder is here. > <https://drive.google.com/file/d/1L8JiX0rtDZO99rVnQKNjUH7m-ZgFz2Un/view?usp=sharing> > The > ways look pretty clean. The only accessory I have is a magnetic chuck. > > I don't really need a surface grinder, but no shop is complete without one. > Once I started to use it, I realized that my right arm and shoulder really > aren't suited to this type of manual work. > > The longitudinal travel is just over a foot, and it takes about 3-1/2 turns > of the crank to go that distance. I'm thinking around a second per turn > would be about the maximum. So, that's 60 RPM. I'm thinking of a 1:6 ratio > on the timing belt pulleys, so that's 360 RPM at the stepper which is > pretty slow. A full stepping rate would be 200 * 360/60 => 200 * 6 which is > only 1200 steps per second. > > An alternative would be to provide more gearing, but I don't think it's > practical to get more than about a six to one ratio in a single belt > reduction and I'd like to avoid mechanical complexity if I can. > > Thoughts? > > Ken > > Kenneth Lerman > 55 Main Street > Newtown, CT 06470 > > > > On Fri, Feb 4, 2022 at 7:13 AM Chris Albertson <albertson.ch...@gmail.com> > wrote: > > > If looking for lowest cost solution you can us the old "Atom" computer to > > control the grinder as long as you do not need to run the mill and > > grider at the same time. Get an Eiternet interface Mesa card for the new > > machine, You need two config files, just load the one for the mill or the > > one for the grinder. > > > > Then someday you buy a second computer you only have to move the Ethernet > > cable over. The best option is a newer version of the Atom. They seem to > > sell for just under $200. Finally Newegg.com always has many used oe > > refurb PCs Used PCs sourced locally can be a cheap as "free" > > > > But 9ld PCs tend to burn up a lot of power. I am trying to get mone to do > > "wake on LAN" so it can not use power until I need to log onto it > > > > On Thu, Feb 3, 2022 at 6:52 PM Kenneth Lerman <ler...@se-ltd.com> wrote: > > > > > I'm considering converting a surface grinder to CNC. To start, I'll > > > probably just convert the longitudinal and transverse axes. > > > > > > I'll go with steppers for this -- I'm thinking NEMA-42 motors. > > > > > > My current Bridgeport clone uses servos and Jon Elson's hardware on a > > > little Intel Atom Box. I'm thinking of using a Rpi for this. It will > > need a > > > minimal display/control panel when completed, but initially will need a > > > display with touchscreen or mouse and possibly a keyboard. In the long > > run, > > > some buttons. and perhaps an mpg might be useful. > > > > > > I'd like to use a raw Rpi without adding special hardware directly. That > > > probably means using a USB or ethernet interface to control the steppers. > > > I'm thinking of using Mesa hardware. > > > > > > Can someone suggest the most cost effective way to do this? (Although I > > > have to admit, that after buying the timing belts and pulleys, the > > > steppers, power supply, stepper drivers, ..., it's too late to be really > > > cost effective.). And the surface grinder only cost me $300. > > > > > > Thanks, > > > Ken > > > > > > > > > > > > Kenneth Lerman > > > 55 Main Street > > > Newtown, CT 06470 > > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > > -- > > > > Chris Albertson > > Redondo Beach, California > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
