Rotary table, Stepper Motor & Arduinos

[john fletcher 1Participant @johnfletcher1]

Some years ago there was an article in MEW using a Stepper Motor attached to a rotary table and controlled by an Arduino. Will some one with an index, please tell me the MEW number or month and year of the article. Thank you in anticipation. John

[Michael GilliganParticipant @michaelgilligan61133]

https://www.model-engineer.co.uk/forums/topic/latest-mew-index/

MichaelG.

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Edit: __ There’s a fighting chance that this is the one you seek

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[SillyOldDufferModerator @sillyoldduffer]

Or if you fancy building mine, this link is to an unpublished article.   (In rotary_table.pdf)

The Arduino project is in the folder  keypad_i2c

Background:  The late John Stevenson didn’t like Gary Liming’s software because it uses nested menus, so I wrote this one which uses a keypad:

Decided not to finish for publication because a few similar projects got in first, so it’s a bit unpolished.   Been built by 4 or 5 others though, so tested and works.   You’re welcome to it, and I’m available if you get stuck!

Dave

 

[JourneymanParticipant @journeyman]

Have a look here:- Journeyman’s Workshop – Rotary Table for one of the many on-line builds.

This is of the original version that Dave refers to. Some of the links may be a bit out of date and not work, it was a few years ago.

John

[JourneymanParticipant @journeyman]

Main thread on this is *** HERE ***

Had some difficulty finding it as none of the old links work. It is very long❗️

John

[Speedy Builder5Participant @speedybuilder5]

Thanks DAVE, your project noted for the future – who knows ??

Bob

[duncan webster 1Participant @duncanwebster1]

I built SOD version, but tweaked the code to have acceleration/deceleration ramps so it turns faster.

[John HaineParticipant @johnhaine32865]

I can recommend the World of Ward products.

 

[John HaineParticipant @johnhaine32865]

https://www.worldofward.com/

[Ian HewsonParticipant @ianhewson99641]

X1 for Wold of Ward, works well.

Ian

[Colin HeseltineParticipant @colinheseltine48622]

I have the World of Ward one which works very well. I also made an Arduino version which uses SOD’s software which also works very well. The W of W one is used on Bridgeport and the SOD version is linked to a Cowells Dividing Head.

[john fletcher 1Participant @johnfletcher1]

Many thanks to all who responded to my SOS, of using rotary table stepper motor and Arduino. Issue 249 is the one. I’m fixing a friends and need details. John

[SillyOldDufferModerator @sillyoldduffer]

This forum gets my goat sometimes!  John’s post in which he explains he’s mending an existing controller for a friend, not in the market for a new one, just elbowed in before this one..  John’s clarification wasn’t there before.   Seems the forum doesn’t maintain strict chronological sequence, and posts are sometimes delayed; they’re in the system, but not displayed yet, reason unknown.  Makes it appear as if members aren’t reading the thread properly!  Doh!  

 

Quick guide to pros and cons:

They all use inexpensive modules.

Gary Liming wrote the first rotary table driver.  Uses an Arduino with a DF Robot LCD/Keypad.

 

The Achilles Heel of Gary’s design is the LCD module only has 5 awkwardly positioned user buttons.   All the controls have to be crammed into 5 buttons. Done with a tree of nested menus, which the operator has to learn and navigate.  Slow and not obvious.  Also hard to add new functions because Gary’s already at the limit of what can be done conveniently with 5 buttons.  That said, Gary’s rotary table isn’t that difficult to learn, and it does all the basics.

The builder has to buy the modules: plugs/sockets, Arduino, PSU, TB6600 Stepper Motor Driver, and then fit them into a box.   The 5 buttons fixed to the LCD module make positioning the module on the box a tad awkward, and a man with a soldering iron might prefer to fit proper push buttons with longer leads instead.

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The limitations of Gary’s LCD-Keypad are overcome by substituting a separate 2×16 LCD module and a 4×4 keypad, also widely available and inexpensive.  Having 16 buttons makes the user interface much more obvious.

My build is based on a standard hexadecimal keypad, i.e. 0 to 9, A, B, C, D, * and #.  To fit I’ve relabelled common functions so Jog becomes B=Bump!   Numbers can be typed directly.  I’ve added a REWIND function, with backlash compensation, and the table’s worm ratio can be changed on the fly, useful if the driver is used with different tables.  Other programs pre-set the ratio at compile time.

My driver has a Numeric Control feature.  An optional link to a PC allows the controller to tell the PC what it’s doing, and the PC can control the stepper by sending the same format back as a command.  Thus a  manual  job can be recorded and then played back to automatically control the table from the PC.   I’ve not found it useful in practice, but if you need a controller that does baby NC, then build mine!

Like Gary’s project, the builder has to buy and assemble the hardware.  Nothing critical, apart from making sure it will all fit inside the box!

My own build is almost solder free, and though the prototype’s been reliable so far, best practice is wiring looms and soldered terminations, not plugged in jumper wires!

Plenty of room for improvements.   I used a Uno, but a Nano should be fine too.  My TODO list includes spinning the table faster, which also requires acceleration to be ramped up and down.   Not a small change cos I want to generate the pulses with a hardware timer, so I keep putting it off!

The software is free as in beer and speech.

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The advantage of the Ward is it comes pre-built, or as a kit, or as a collection of modules.  Their bespoke keypad is nice!  More expensive to buy but less trouble to build. A ready to go black-box is best choice for those who don’t have the time or interest in building their own, and even if you fancy a build project, kits save time!

Dave

 

 

 

 

 

[Peter Cook 6Participant @petercook6]

I built and use Dave’s version on my rotary table. It works very well and the interface is nice to use. The one thing I would add is to be careful of thermal issues. I built mine into an ABS box, without thinking through the issues. The stepper driver gets VERY hot if there is no airflow.

I ended up adding a little 40mm 12v fan from my computer bits box, and drilling some holes in the opposite end.

[John HaineParticipant @johnhaine32865]

Though I have the Ward, there is another approach which is also Arduino based.  That is to run GRBL on the Arduino which can control 3 axes with acceleration and other features available.  So one axis could be rotary, and another could run the table power feed.  Only problem is you need to send it g-code commands but a simple GUI could run either on another Arduino (if running GRBL on something like UNO  or Nano), or the same processor probably with one of the updated GRBL versions on a more capable Arduino (Pi Pico would probably eat it for breakfast).

Once you can do coordinated rotary and linear moves, things like knurling become possible.

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