stepper & Servo Control

[Alan Case]

Hi, In my spare time I am thinking of trying to build a small label engraver, hopefully utilising some of the gear I have collected over the years. Is there someone here who could post some links to a good tutorial site on stepper and servo motor control. This is an area I am not very knowledgeable in. Also I would be interested in any comments you guys have on the design (electrical) of this item. 3 axis
with the ability to engrave letters and line drawings in multilayered plastic sheeting. Regards Alan Case

[Eric Nelson]

Hi Alan,

For what you want to do, you'll want to look for stuff about Computerized Numerical Control (CNC)

Google found This Link (http://www.mendonet.com/cnclinks/) when searching for "CNC tutorial". Lots of stuff here!

Some of the links on the page are dead (the ones that seem most informative, of course! :rolleyes: )

Have fun!,

-Eric

[Alan Case]

Thanks Eric

[93lt1]

If you build one of these "engravers" build a duplicate and GIVE it to me....these things are very expensive.

[rsdoran]

Another good place to look is Oriental Motor website:
http://www.omusa.com/products/CatalogPdfs.htm

I think you are familiar with AB so dont forget to search their site:
http://www.ab.com/manuals/io/1771/1771-um002a-en-p.pdf
Try a search there for CNC also.

The other major stepper motor maker is Sig Positec (bought Berger Lahr): http://www.sig-positec.com

[Steve Crotty]

Here is a stepper motor driver I like to use. You can get it as a free sample from Allegro.

http://www.allegromicro.com/sf/5804/

It doesnt support very high current though, 800 mA from what I remember. Do you already have a stepper motor in mind? Anyways, it is really easy to use (although one time I managed to actually explode one).

Good luck

-Steve Crotty

[Gerry]

This sounds like a very ambitious project! I'm curious about the need for 3 axes - do you plan to engrave spheres? I see this as similar to a plotter and would consider cannibalising one if this was my project. You might end up being able to engrave directly from Autocad. I don't think I would attempt that with a PLC.

On the other hand, if you're building a kind of sophisticated pantograph where you physically trace whatever is to be engraved, then it would be much simpler.

Regardless, the first and most important step in designing a servo system is determining sizing and gearing. If you get that wrong you'll have nothing but grief.

[rsdoran]

I worked for a company that made or converted pentagraph burning machines to CNC burners. The machines only used 2 axis ( 2 motors on 1 axis ) and 1 for the other axis. The main problem he had to overcome wasnt creating ovals or circles, it was triangles ..ie right angle cuts, the nature of the cut wants to round off sharp edges. I assume the purpose of 3 axis is to add more control to the pin/engraver by giving it movement along with forward/reverse and side to side.

Anyway the reason for NOT using a pentagraph is two fold..less space is needed and the layout can be done with drawings. The ambitious part is creating the software that can communicate the coordinates to make the appropriate marks/cuts. I didnt learn all the aspects of the conversion process, loading the drawing to the computer and how it was translated/transfered to the plc to actually make the drawing. The machines used 286/386 computers so that may tell you how long ago this was.

I probalby have the resources for a project like this but not the time or room to do it...wish I did. Awesome learning experience.

[Alan Case]

The third axis is only to lift the engraving head up away from the object to allow the engraver to move between letters. There are some quite good plans (well I hope they are good) for sale on the web. I know it wont be a cheap excercise but I am tired of making my labels on a pentograph type machine. Here is a link to one such machine. http://www.data-cut.com/Page2.html

Regards Alan Case

[Laurent]

Hi Alan,

I dug up this old post... always interested by 3 axis engravers ??

If yes, have a look to this site : www.deskam.com

I have built 30 complete 3/4 axis machines with their DeskWinNC package (controller board + software). Softwares can be downloaded for tests. Since I import stepper drives in France, I was looking for powerful but low-cost solutions, and didn't want to integrate our usual PLCs : I've been very surprised, we got very high level results !

Have a look to their DeskEngrave software (freeware), allowing to type and format texts, and outputting g-code files... !

If you're always looking for ideas or tips on this subject (motors, drives, axis, softwares...), don't hesitate to get in touch.

Regards

[donvw]

E-bay 1758373302 might work out.

[Jiri Toman]

Go to www.cyberpakco.com. If you like call them and ask for Rich.
They have done many applications just like the one you have just described. They also have a line of very inexpensive and reliable
stepper drives and indexers.

[Jiri Toman]

The link is www.cyberpakco.com

The link in my other reply will not work because of the dot after
the com

My mistake there needs to be a white space after com

No more dots