What keeps you from using your rotary axis?

Topics related to wrapped rotary machining in Aspire or VCarve Pro
AlanAndrews
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Re: What keeps you from using your rotary axis?

Post by AlanAndrews »

After some problems with the controls and motors on my ECU860, I've now built a 3 axis retro fit kit - using uprated and separate controls/drivers, power supplies and closed loop motors.

Everything has been designed to allow me to add a 4th axis in the near future. I've even added the 4th axis wiring to the looms and pre drilled the enclosure in readiness.

So I'm keen to see what comes of this and to get some hints and tips on specs and usability.

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IslaWW
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Re: What keeps you from using your rotary axis?

Post by IslaWW »

Brady Watson posted the following on the SB Forum as an answer to this same question. It appears that all variations of a rotary axis have the same issues. Whether you buy from mfgr X, Y or Z, build your own, or buy one online, the following seems true.

Quote:
Many of the challenges I had early on are still true today. Thought I'd chime in from memory - although things have gotten WAY better over the course of time where kids today don't know how good they've got it when it comes to indexing....

1) No instructions on how to mount the indexer and hook it up in software.

Long, long ago in a land far far away, I bought my first indexer from SB. It came with a single sheet of paper that showed the difference between a cove and a bead. There were no instructions on how to mount it. How to set it up in SB2 or later SB3....The head and tail stocks were too tall to mount on top of the bed and clear the Z, so you were guaranteed failure right out of the box. Mine sat for a few years before I messed with it. I wound up mounting it off the table and later, just bought a lathe, converted it to an indexer and welded another 18" onto the end of my table just for the indexer. This way it was always setup. In more recent times, SB has provided mounting options for the indexer. It only took like 20 years, but hey...they do it now.

2) I've got it mounted, now what?

Early on there were NO gadgets, tutorials or help (even from SB because even THEY didn't really know how to run the indexer, aside from a simple MB move). There were a few guys doing 3D incremental indexing (not really) using ArtCAM combined with calculating the 'magic number' using a function of Pi and your Unit Value to basically wrap a 3D toolpath around the indexer. There were secret handshakes involved and there were still plenty of questions. Documentation has gotten WAY better in more recent times, although it still leaves a bit to be desired. I suppose you must prove yourself worthy by tracking down all the info from SB and Vectric and then understand it all - which is 1000x easier than it was for me.

3) What kind of file do I need for the indexer and how do I make it?

Depending on the desired outcome, the kind of model needed for the indexer was a source of confusion. Does it need to be 'full 3D'? Could I make in in ArtCAM/Aspire, a 2.5D program? What about models that dipped in the center that couldn't be unwrapped? What then??? What about if I wanted to miter/fishmouth a tube so I could weld it to another on an angle? How about just engraving on the surface? Can I do a statue and get full coverage? How about machining something on 2,4 or more sides using conventional 3-axis toolpaths? How do you do those barley twist things with the form cutters? Can I use this thing as a lathe? What's the difference? The answers to these questions only came after doing a ton of research, playing around and actually trying things out - there wasn't anybody out there to ask...

4) How do I make money with this thing?

(crickets chirping...) Still trying to figure that one out.

The indexer is one of those things...you just gotta have one. It has a certain mystique to it...it can cut out ANYTHING!!! (or at least that's what we believed when we bought it) - It's interesting in the sense that, for those that bought one, it seemed to represent a level of skill we all aspired to reach at some point in our CNC 'career' or whatever. It represented possibility - whether real or imagined.

-B
Gary Campbell
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IslaWW
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Re: What keeps you from using your rotary axis?

Post by IslaWW »

Guys...
Randall, Brady, Michael, myself and some Vectric staff will be at McGrew's Camp willing and able to instruct, explain and clarify most anything rotary. There may be some rotary related surprises coming in the future from Vectric.

That said, most of us that understand the rotary axis "stuff" feel that it is straightforward and tho not simple, should be relatively easy to learn. In other words, "When you understand rotary work, you cant seem to understand what it is that those who don't get it need to be told"

Can you help a brother (or brothers) out?
Gary Campbell
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ATC & Servo Controller Controller Upgrades
GCnC411 (at) gmail.com

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Rcnewcomb
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Re: What keeps you from using your rotary axis?

Post by Rcnewcomb »

What problems/confusions have any of you run into trying to create wrapped jobs?

I'll throw one out there that people run into. You have the cool STL file that would be perfect for your 4th axis. You encounter this error....
Screen Shot 2018-02-24 at 4.55.05 PM.png

What are other examples of errors you have run into with trying to build wrapped jobs? What ai want to do is get a collection of problems/errors and then explain what to do about it.
- Randall Newcomb
10 fingers in, 10 fingers out, another good day in the shop

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Re: What keeps you from using your rotary axis?

Post by LittleGreyMan »

Randall,

Maybe demonstrating a cylinder seal is a good way to explain rotary axis as it's the exact opposite process. People who have issues figuring the process will be able to see it in action in a very simple way.

If you can use a cylinder to generate a bas-relief on a flat piece of clay, you can just do the opposite and wrap a bas-relief.

See this slide show at 6:40

http://slideplayer.com/slide/9433608/
Best regards

Didier

W7 - Aspire 8.517

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mezalick
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Re: What keeps you from using your rotary axis?

Post by mezalick »

LGM,
I have such a model that I use in my rotary training classes..
It's a rubber mold that is bendable to show the "flat to round" conversion.

I can bring it to McGrew's as a visual aid,,,if Randall think's it worth anything.

I'm going to be there anyway.....:)

Michael
Michael Mezalick
https://www.youtube.com/user/mezalick
mm@mezalick.com

LittleGreyMan
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Re: What keeps you from using your rotary axis?

Post by LittleGreyMan »

mezalick wrote:It's a rubber mold that is bendable to show the "flat to round" conversion.
It seems more straightforward. And probably less expensive than buying an actual Sumerian cylinder :D
Best regards

Didier

W7 - Aspire 8.517

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Rcnewcomb
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Re: What keeps you from using your rotary axis?

Post by Rcnewcomb »

It's a rubber mold that is bendable to show the "flat to round" conversion. I can bring it to McGrew's as a visual aid, if Randall think's it worth anything.
Yes, please bring it.
- Randall Newcomb
10 fingers in, 10 fingers out, another good day in the shop

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Rcnewcomb
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Re: What keeps you from using your rotary axis?

Post by Rcnewcomb »

Here is another error that sometimes confuses people trying to get into rotary
WrappedGadgetError.PNG
- Randall Newcomb
10 fingers in, 10 fingers out, another good day in the shop

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Rcnewcomb
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Re: What keeps you from using your rotary axis?

Post by Rcnewcomb »

Sometimes people get part of the model to look correct in the preview, but the backside is wrong.
BadLegFront.jpg
BadLegBack.jpg
598-2-clear.jpg
- Randall Newcomb
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Rcnewcomb
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Re: What keeps you from using your rotary axis?

Post by Rcnewcomb »

You were expecting this:
WrapWrongPreviewAxisGood.jpg

But instead you saw this:
WrapWrongPreviewAxis.jpg
- Randall Newcomb
10 fingers in, 10 fingers out, another good day in the shop

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