Need Dead Simple CNC

[gerryv]

Hi All,

Because of memory and information organizing problems from an accident I have great difficulty with even basic measurements - a conventional mike in my hands is a disaster in my hands. I fare a bit better with a digital vernier but DRO would reduce my current knee depth piles of scrap even more. I think what would be ideal for me would be to go a small step beyond DRO and add some simple memory or sequential step capability in a dead-simple to learn/use device.

This leads me to ask whether anyone has any thoughts on whether the answer might lie in a device such as the $500 Sherline 8850 linear controller/stepper pkg? I never expect to go beyond very basic machine control, it's more an issue of an aid to reducing my calculation errors and as a possible bonus, even helping to reduce the terrible slop that I keep forgetting I have in my hand wheels with some backlash compensation.

Does anyone have any experience or successes with this or some similar controller/stepper setup and if the Sherline unit might be useable on other machines with using a custom mount for the stepper?

Thanks much,
Gerry

[ironDigit]

I don't really think a cncconversion can make up for calculation errors since YOU will have to tell it exactly what it should be doing ,meaning offcourse that if the values are (way)off on a cnc machine it will even cut into itself while when operating manually leaves chance to correct any problems.

Thats why i don't think a cnc-retro can not replace the use of a DRO in your case.

As for making up for slop(backlash) in the handles : CNC and BACKLAsH are a bad combo though software can compensate for this ,it is very limited and can not get rid of too much "slop".though i have not experienced this myself maybe some1 else can jump in.I need say there are many imho good ways to get rid of slop even on a budget ,so this shouldn't stop you.

i guess i'm trying to warn that even after completing a cnc-conversion there is still alot of calculating concerned with cutting and i think it's even more critical here since a machine can't compensate for error in the last minute.Though with limitswitches and creating g-codes with "ready2go" programs should rule out most critical error.

I'm sure i didn't cover all concerns but i'm sure there is some1 willing to add to this.

whatever you decide : GOOD LUCK.

[pointcloud]

Not being a smart ass but it sounds like a sharp pencil would help loads.

If you have trouble remembering you have 0.125 backlash in your X. It would be more than fair to say a machine crash would be in you near future...

I forget things, not to bad with math either but I have crashed'em.

Nothing to simple about cnc, well except watching the machine cut away...

But here is a site with great support and he's a really nice guy... http://www.candcnc.com/ Oh and super smart in the retro and total build of a machine....

Later
M

[gerryv]

These are good counter-points and insights and much appreciated as they educate me to some possible unexpected surprises. But, if no one minds, I still need a bit more "convincin" as I've got a pet 15 year old project that drives me ...a good thing.

You're right, I DO need to think about crashes - I still think there's not a fuzzy-logic system (anyone still use that buzz-word?) yet that is better/faster than a combination of eyesight, experience & intuition. And, sensors and switches are pretty low-cost these days I think so that's good value advise that I can follow.

Maybe the following info will help some of you get a better handle on the real need so you can better help me, or others like me, that just happen to like making things work/that work. It doesn't really embarrass me because I've got a goal in mind that's more important, so fire away if you enjoy solving unusual problems once in a while.

I wouldn't post this here if it was just crying in my soup. With that in mind, if I'm wrong, and this post is not appropriate and that's a-ok with me too - forums need rules to stay relevant. But I'm used to forums and I think it might be okay because it presents an out-of-the-ordinary challenge for guys that have the technical expertise and also, if I'm a bit lucky, are also experienced enough to recall using "some kinda hardwired" pendant or dedicated console to plug in a series of go-to coordinate commands, but not necessarily much more.

As suggested, in my case a big red OSSTQ button would also be needed too ( Oh S#*t, Stop This Quick). That's where your suggested sensors or limit switches come in, thanks much. Come to think of it, I'm not sure I'm all alone here! Maybe the only difference is that I usually can't tuck these experiences away for future recall.

Anyway, I'm quite not giving up yet on CNC so... if there is anyone who remembers the excitement of its horse-and-buggy days (was it ladder logic or was/is that PLC's? - I could easily be wrong) but also may know of a "current" keypad or similar "simple though limited" control means, it would be great to hear your thoughts.

Thanks much,
- Gerry

[pointcloud]

The link I sent you has a pendent that you can drive the machine with your self, it looks as if it would do it with only one finger.



Yes I know what fuzzy logic is ( with a bad memory how do you remember).. I used it to anticipate growing enviorments for a hydroponic greenhouse... That was a fun time but another story...

Big red buttons can easily be wired in on the systems from the link or others. Also limit switches will not protect everything.. example you have to cut a pocket, where is that switch goinng to be? You have to CUT, and you may cut as much as 2 or 10 inches maybe more.. So no switch for that... another thing is you really want to sit around the machine while it runs a multi-hour part, just to push a button?


Ok. I am not trying to detour anyone from cnc. SO BE MORE CONFIDENT IN YOURSELF...

There is software that is free if money is a handycap, that will do most anything you want to tackle in you garage.
Mach 3 is a great control software, supported through many forums including there own... It's like $150 or 170.. Those are the only real things you'll have to learn... After the install of mach it is really more like opening a file in any program. All other things are relative. like tools, where the machine is in relation to work, work hold down, and so on that is the same as manual.

and as to apporiate I'll shoot the shi# with you about almost anything...



You asked: (but also may know of a "current" keypad or similar "simple though limited" control means, it would be great to hear your thoughts.)

So did you even follow the link? cause there is one there, it runs with mach....

[gerryv]

Guess what, I didn't remember that you posted a link! But if I go to it right now, with zero distractions...

[gerryv]

OK, I just took a quick look and it shows promise for sure. I'm not sure I can put this in the right words because I have no background in either CNC or programming but I'll give it a shot. This device appears to offer many more functions than the Sherline product. The difference appears to be that this one appears to need some additional hardware/software (processor) that clearly offers MUCH more capability. However, there's also the implication that it would require me to "write some code" Ah-h-h-h! (cry of terror). I may be totally wrong of course, in assuming it (or Mach 3) may not have some canned routines that require nothing more than the pendant/other hardware and Mach 3 - I simply don't know and reading the features is over my head, not because I can't understand things, but because it's all greek to me at this point with no previous exposure. Thanks much for the support. - Gerry

[pointcloud]

It uses the same mach 3 as sherline often does. So the difference maybe sherline is assembled.

canned is a pretty big word for a newbie...

I have a system simular to the one you looked at on the link... I have a pendant. So I crank up the computer, open up mach 3, flip a switch to enguage the servos and vula the joy stick will bring joy... I would say you might make some streight lines, and even at an angle, but really cam type software isn't that hard. Infact in the amout of time I have taken to write in this thread is more time than it took me to figure out how to make some desent code useing sheetcam. I admit I have some exp under my belt, but A MAN CAN DO WHAT A MAN WANTS TO DO, IF THAT MAN WANTS TO DO IT BAD ENOUGH.

I may not be the sharpest tool in the shed, but there are some here that are so dull they couldn't part loose dirt and they do cnc...


On that link I posted... Shoot them an email.... They will answer any questions you may have, and then some...They may even have exctally what you want........ I have to say I am not afliated with them, but I have had all questions answered. They have a great looking kit and I am looking into fitting a mill with his stuff... If you were to call them ask for Tom... and tell him how you heard of him..

Btw they have there own forum in yahoo groups for support on there products and more...

I hope I gave some insight..

[gerryv]

Sure did. Two cents plus some! Thanks much!

[pointcloud]

I just reread your first post and you know what? You will still need that pencil... You will still have to check SOMETHING you make.. UNLESS YOU ARE MAKEING ART, which you would not need to measure in the first place but visiually give it a once over...

I think you will always have a problem, in that respect if it's REALLY as bad as you say... I have the oppisite problem, I will write it down backwords, but retain numbers very well.. I think I bumped my head too... lol

Hey do a search over in the where are you at thread http://www.cnczone.com/forums/mentors_apprentice_locator/ for somebody near you... I found I had lots of neighbors, new and old to cnc..

[gerryv]

With a better grasp on these initial pro's and con's as they may affect me. I'm wondering if the following lathe and mill "setup" may already be available in an off-the-shelf CNC package running Mach 3 software on one computer?

First: A setup which would have the ability to more or less emulate manual/DRO lathe and mill so that even if hand wheel control were not offered the operator could emulate this by plugging X, Y, Z and maybe even A "go to and stop" directions by simply plugging these coordinates into the appropriate fields on the monitor and clicking a "run" icon, but not having to write G code, at least to start with but leaving the door open to gradually biting off more. This may be naive thinking of course but nothing ventured, nothing gained.

Second: Find someone who could write me a routine that would require me to hold down a key/button/whatever for anything to run at all. Lift my finger, it stops. A nuisance for many for sure but a possible blessing for me. That way, the opportunity is there for me to intuitively and immediately stop travel in any/all coordinates instantly just by lifting my finger during those visually prompted "Oh S#*t moments" even if the chuck is still spinning down.

I'm thinking of something like the Syil C6 & Super X3 combo. Well beyond my budget at this point but maybe something to save for?

Thanks so much for the on-target advise so far. My skin is thick - any further advise on this thought would be most welcome.

Thanks kindly,
Gerry

[pointcloud]

Simple answer Is yes on the BUTTON and plugging in where to go...

The button can be done with a limit switch, wired normally open, and you'd hold it or whatever....

Mach has a MDI screen manual data imput... It is in g code form but THE CODES WOULD BE SIMPLE... like G1 X1 F50, Would be a feedrate movment of X 1 inch... None of that circular intrepolation g02 g03 and so on.. just G1 X,Y,Z,A,B,C F=feedrate in ipm/mmpm

So yes to all questions... No need for any extra scriting for the RED BUTTON...

I can't suggest which of the two mills you picked out might be better, I have never see one up close or used one..But I think that they both use Mach 3....