Rotary table indexer

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Originally Posted by wiseman9986

I know this has been asked before but I couldn't find a good answer what would be a good stepper motor and driver for a 10" rotary table

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For 'normal' use a typical Nema 23 motor of around 2-4A will easily spin a 10" table.

I use a similar motor but set the current low to just over 1A and via a 90:1 worm that turns a 10 inch swing lathe head (with drive motor still engaged) along with any work in an 8 inch chuck without any problems.

As the load on the stepper gets higher the torque available falls, so worse case you may need to run it slower but for division speed isn't that much of an issue.
You can get around this by increasing the supply voltage to the driver (if it's higher than the safe supply voltage for the controller then you would need a separate power supply for the controller - a small 12v wall wart type would be fine).

So in short, find a Nema 23 motor of around 2-4A and a suitable driver with similar capabilities. (Preferable a driver with half step capability - which should be most).
The driver doesn't need to be anything clever, just a cheap driver off eBay. They're cheap enough so you can buy a spare or two, although avoid anything that uses the L298 chip and keep the voltage a little lower than the max rated voltage.

Can anyone recommend a stepper driver, I had a ?Stepper™ : CNC Stepper Motor Driver Board which worked perfectly for 10 years. It has now failed and I can’t find the same one. I have tried a TB6600 stepper driver and a Stepperonline DM420Y bothe of which I cant seem to get the steps correct with. There is some microstepping issue that I can’t figure out. The old ?Stepper™ had just full, half, quarter, and eighth of which I used Half Step mode.
Thanks

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Originally Posted by Redbrown

Can anyone recommend a stepper driver, I had a ?Stepper™ : CNC Stepper Motor Driver Board which worked perfectly for 10 years. It has now failed and I can’t find the same one. I have tried a TB6600 stepper driver and a Stepperonline DM420Y bothe of which I cant seem to get the steps correct with. There is some microstepping issue that I can’t figure out. The old ?Stepper™ had just full, half, quarter, and eighth of which I used Half Step mode.
Thanks

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Hi, the cheap and cheerful TB6600 should work fine. I use them all the time with no problems.

Set them to half step (400 steps) and in setup on the controller find "Swap Clock Pulse" and make sure it's set to "High" (the default is "Low" for some obscure historical reason that escapes me now - when I update the firmware next I'll flip it, most drivers require it high).

The only other possible issues are "steps per 360" is incorrectly set or there's some slippage in your hardware.


Hope that helps.
Steve.

Cheers Steve I will have a look tomorrow thanks for the advice.

Reinstalled the TB6600 4.5A CNC Single-axis Stepper Motor Driver Board (ebay) with no problems. Thanks again.

Hi, All

Just ordered two of the Built and Tested Modules, Keypads and Overlays from Steve Ward, a great looking product.

I'm currently working in Germany, glad to have found this group

Heres my youtube channel for the curious.
https://www.youtube.com/user/CeeltdNew

Thanks
Carl

Hi Folks, I bought the pre built/tested unit and keyboard. I've built it and connected it to a TB6600 driver a 200 step nema 23(2.8A) motor, my table is a vertex HE4 90-1 ratio.
Everything works fine but no matter how I set it in the settings or set the dip switches on the driver the thing just won't drive right. If I set it to DEG.and set it at 90° it only turns the table 10°? I've set the driver to 400 steps and it won't run at all, in fact I can only get the motor to run properly if I set all the dip switches to the default off position. I assumed a faulty driver so replaced it with another new one from a different manufacturer and I get exactly the same results. Tearing my hair out now (which at my stage in life i can't afford!!) Any suggestions or advice will be gratefully received. Many thanks in advance.

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Originally Posted by Smithwrecker

Hi Folks, I bought the pre built/tested unit and keyboard. I've built it and connected it to a TB6600 driver a 200 step nema 23(2.8A) motor, my table is a vertex HE4 90-1 ratio.
Everything works fine but no matter how I set it in the settings or set the dip switches on the driver the thing just won't drive right. If I set it to DEG.and set it at 90° it only turns the table 10°? I've set the driver to 400 steps and it won't run at all, in fact I can only get the motor to run properly if I set all the dip switches to the default off position. I assumed a faulty driver so replaced it with another new one from a different manufacturer and I get exactly the same results. Tearing my hair out now (which at my stage in life i can't afford!!) Any suggestions or advice will be gratefully received. Many thanks in advance.

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I've replied to this via email but I thought a reply here might be of help to anyone else with a similar issue (and in case my email gets whacked by a spam filter).

So setting the motor to 400 steps should allow it to run without any issues, that its making a noise suggests an issue between the driver and the motor.
(More so because you can get it to move with other settings.)

In the past issues like this are usually because the motor isn't wired correctly to the driver.
(Usually because the motor is cross wired).
The other possibility is a duff motor although this is fairly rare.

So the motor has two windings - A and B.
These are provided by 4 wires usually labelled A+, A- and B+, B-.
They should be connected to the same terminals on the stepper driver.

I would start by checking these.

Big Thank You to Steve, this is now sorted. For some reason the high speed was set to 9000, I've reset it to 1000 and everything works perfectly.

I've looked and searched but can't find an answer so here goes - I'm a complete beginner BTW

Do I need a closed loop system ?

As this post was originally posted 14 years ago, I take it things have moved on a bit

I was looking at this setup
https://www.omc-stepperonline.com/cl....html?limit=50

We are looking at powering a 17" rotary table for hobby use and its fist job will be a half size traction engine crankshaft.

Many thanks for your replys
Nick

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Originally Posted by Dragracer1260

I've looked and searched but can't find an answer so here goes - I'm a complete beginner BTW

Do I need a closed loop system ?

As this post was originally posted 14 years ago, I take it things have moved on a bit

I was looking at this setup
https://www.omc-stepperonline.com/cl....html?limit=50

We are looking at powering a 17" rotary table for hobby use and its fist job will be a half size traction engine crankshaft.

Many thanks for your replys
Nick

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Hi Nick,

You don't need a closed loop system but there's nothing to stop you using one.
(I get "page not found" for your link)

The system has been tweaked and a few features added since the first iteration but it basically still does the same thing.
I'd recommend you have a read through the manual to see if it will do what you're expecting.
http://www.worldofward.com/downloads...nual%202.2.pdf

17" is a *big* table!

If you have any questions I can answer you can contact me directly (my email address is on the first page of the manual).

Steve.

Thank you Steve,
Yes 17" is large but that doesn't mean we will be doing big stuff, if / when we get it up and running I will post a couple of photo's.

Every thing now bought - just waiting for the postie to delivery.
Nick

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Originally Posted by kwackers

Hi John,
that's exactly how it works.

So basically internally it multiplies the number of divisions by the actual division its on then divides the result by the number of steps for a full circle - this gives it the nearest number of steps it needs to get to that division (doing the multiply first prevents loss of resolution although it means it needs 32 bit maths which is why the max steps per rev is 16 bit).
Internally it knows exactly how many steps it's currently taken so simply adds (or subtracts) that from the answer above to get the number of steps to take.

This means there isn't a constant number of steps since it may need to take an extra step (or lose one to be accurate).

In practice the accuracy of the maths is half the single step resolution, so a 400 step driver on a 90:1 worm gives you 0.01 degrees per step so the accuracy is 0.005 degrees. (Mechanical accuracy not withstanding).

Hope this answers your question.

Cheers,
Steve.

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I have just replaced the Arduino based controller system on my rotary table stepper conversion with Steve's built and tested module and keypad/overlay to overcome the non integer cumulative error on a 290 tooth skeleton clock main wheel. The system is easy to instal, works well, looks great and solved my problem.
Thanks Steve

It's been a while since I updated anything so I though I'd mention there's a new version of the firmware available.

This version (3.03) has a number of changes.
These include:

• Both stepper ports are now active and can be swapped over in the machine profile (the ready built unit uses this to select either the internal stepper driver or an external one).
• A simple gear cutting mode has been added using the second stepper port to drive the cutter, this replaces the use of two controllers.
• A new motion engine which offers linear acceleration and higher top speeds.
• The 16 bit limit for "Steps per 360" has been removed so values larger than 65535 can be entered (allows microstepping and slow feedrates for cutting with small cutters whilst rotating and the use of microstepping only drivers, i.e. some Geckos).
• Updated programming mode to support the linear functionality added by gear mode.
• The enable line has a pre-settable delay allowing it to be used to drive an electro-mechanical brake.
• Various changes to setup reflecting the above.
• 'Goto Angle' allows 360 degrees to be entered (for machining a full circle)
• Some changes to nomenclature both on screen and in the manual to differentiate between the two ports.
• Degree and Jog modes now work with “ideal position” rather than actual position which prevents accumulated errors (and shows desired position rather than actual on display).
• Degree and Division modes now can recover from 'Cancel' and 'Stop' commands (subsequently pressing one of the index button moves to the correct position for that index).
• Removed ability to jog in Degree and Division modes (it was messy and caused other issues – plus nobody seems to use it).
• (And probably some other bits and pieces I've forgotten about...)

The new firmware requires a 18F4620 since the 4520 didn't have enough memory.
It's a plug in replacement for any existing chips.

Details in the downloads section of my site. (Firmware, updated manual etc etc)
World of Ward :: RotaryController

So included is a photo of my stepper operated indexer for cutting syncronous pulleys and gears and the gcode that runs it. A is the spindle, B is the brake or locking. my question is how to how to make m47 repeat X amount of tihttps://www.cnczone.com/forums/attac...d=476320&stc=1mes. Thanks