Worth the Price? / Rotary Axis Setup

OK Roger I tried all you said and it moved but didn’t cut a dowel. I’m attaching a YouTube video along with the pics you asked for. Also I input the numbers in MDI you noted above and it only moved a few degrees. Still stumped.

Here is the video link.

@DaBooBear Did you change the step angle to 0.3° like I said last night? Still shows you are using 1.8° in the pictures.

No. I’m an old guy. I forgot. Will do it now.
I used 1.8 because that’s what Nema said to use.

I believe it would be that just for the stepper motor but with the belt driven chuck and everything it should be 0.3. I believe it states in the Amazon listing from the manufacturer that it’s step angle is 0.3° also.

We have liftoff Houston. Roger that .3 step did it. I am such a happy camper and so appreciative of the help from others but mostly you. You understood most of this was new to me and stuck with me guiding me to a successful launch. So thank you. You have a friend for life.

I changed to .3 and ran the toolpath and the result was a full 12” dowel.

Glad it’s working for you. There may be some tweaks here or there you might have to make to the post processor or something but it’s not too difficult. Just look up what the commands mean and you can mess with them if you need to. I believe it should work plenty fine but just in case you can always mess with it to get it working better or whatever you need.

Onefinity ROTARY (Inch).pp (5.0 KB)

Here is the post processor for inches for the rotary.

Thank you so much Roger.

After setting everything up I did a 2”x8” ballister. The rounding toolpath was 24 minutes. The 3D finish was 1:20 minutes. However when I sent the toolpaths to the machine here is the time shown.

  1. Rounding toolpath 25 minutes. That is OK.
  2. 3D Finishing toolpath. 21 hours. WTF?
    I tweeked my motor settings but still no change.
    I can’t figure out why such a difference. Using a Skinny Jenny on 3D Finishing.
    Any thoughts?

toolpath timing in vcarve is an estimate so broad, it covers every CNC in exisitance. You need to adjust the ‘scale factor’ to get it closer to what the controller says it will be.

The Post Processor was based on the 1F. What do you mean “scale factor”?

"The inaccuracies generally come from the acceleration / deceleration of the machine. We do take account of the rapid moves and you can enter the rapid rate for your machine on the form.

However if we tell a machine to move at 200 inches / min along a 200 inch straight line the machine will probably take pretty close to a minute.

If instead of a straight line we ask the machine to cut say a gear wheel with a total circumference of 200 inches, the machine is likely to take considerably longer. This is because the machine will have to slow down to go around the tight curves of gear tooth profiles and will probably never reach its programmed speed before having to slow down again for the next change in direction.

The scale factor in the programs let you approximate this slowdown for your machine, but it will vary depending on the type of work you are doing. Many people will use one scale factor for simple 2d work and another for 3d or VCarving. The best way to calculate it is just to take a note of estimated and actual machining times of a period of time.

For machines where the controler provides an estimated machining time, these should be more accurate as the controller can determine where the machine is accelerating / decellerating and take account of this."

Thanks for the explanation.

Can you give me an example of a project and the time it took to run?

I’m pasting this here too.

Thanks. When you update can you show pictures or a video?

New Facebook group.

Folks, thanks for all the time and effort you put into documenting your experience getting a rotary up and running. I have the machine connected and turning on its own but I cannot, for the life of me, get the pp loaded in vcarve. I show it being associated with my machine but when I calculate the toolpath, the pp doesn’t appear.

Anyone else have this issue? What did you do to resolve?

Thanks again!
Brian

To answer your question, BB.

I did figure this out in VCarve. For some reason, the PP was not available to me when I chose the toolpath for the object. It isn’t until I am saving the toolpath to file that I can select the correct PP.

See below.