## How To: Continuous Rotation & Indexing

Topics related to wrapped rotary machining in Aspire or VCarve Pro
Rcnewcomb
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### How To: Continuous Rotation & Indexing

This is a technique that Milo Scott showed me.

It allows for continuous rotation while indexing. For some designs this technique is much faster. ->Video Example
For other designs is may be slower than standard 3D Rough/3D Finish.

I've attached Milo Scott's PDF file describing the steps in detail.

TL;DR
1. Set up a rotary job with a 3D design
2. Select the spiral layout gadget.
3. Set the Spacing between strands to the stepover for your ballnose bit. In this example I am using a 0.125" ballnose bit and want a 10% stepover. The spacing between strands is 10% of 0.125 = 0.0125.
In my example it says Total Number of revolution for spiral = 2236.99
4. Select the vector that was created from the spiral gadget.
5. Choose the Profile Toolpath.
Set the cut depth to 0
Profile On the vector
Check Project toolpath onto 3D model
Now it will cut the project with continuous turning. Like a 3D finish toolpath it will NOT use the pass depth.
Attachments
1001 Vectric Continuous Turning Round 27 Mar 2021.pdf
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

Vectric Craftsman
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### Re: How To: Continuous Rotation & Indexing

Thank you Randall,

That's VERY interesting. Way above MY pay grade but VERY interesting.
Just moved house and swamped with a list from Mrs. Jim but one day I'll give it a go.

Jim

PaulB
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### Re: How To: Continuous Rotation & Indexing

What a great idea to add the design to the vector.
I use the continuous turning method on most of my rotary jobs, but this takes it to the next level.
this is a "got to do soon" item on my short list.
Thanks

Paul.

SteveNelson46
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### Re: How To: Continuous Rotation & Indexing

Randall,
Thank you very much for this information I try to learn something new every day. and this method of carving 3D with continuous rotation certainly fits the bill. Now I'm trying to figure out how to use it on some of my projects. Thank you again for the information and inspiration.
Steve

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### Re: How To: Continuous Rotation & Indexing

Ditto what Steve just said.
Although I've never used my 4th axis yet.
One Day ! !
Jim

Rcnewcomb
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### Re: How To: Continuous Rotation & Indexing

Although I've never used my 4th axis yet.
Start with a bunch of 2"x"2s. You can trim the corners on your bandsaw or table saw to save time and lighten the load on your CNC. You may be able to skip the rounding process if the blank is small enough and/or the corners are trimmed off.
Use the largest bit possible: large V-bits with an angle >=90 degrees, ballnose, and form tools are great.
Use the fluting and spiral layout gadgets.

Thew two fluted columns were cut in 3 1/2 minutes at 60 IPM at 0.1" pass depth. The Spiral was cut in 5 1/2 minutes.
This was carved from a 4"x4" in 10 minutes and 35 seconds using a V-bit and the fluting toolpath. Even though it is tapered in the middle no 3D work is involved.
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

Leo
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### Re: How To: Continuous Rotation & Indexing

Randall, Thank you for that connection.

I checked out Milo Scotts web site and it is extremely informative, He is very professional and quite talented. One that I will bookmark and use for sure. Some interesting youtube tutorials.

I would encourage all to check out his work.
https://lwmcnc.com/

I do appreciate this PDF from Milo that you posted

Thank you
Imagine the Possibilities of a Creative mind, combined with the functionality of CNC

Rcnewcomb
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### Re: How To: Continuous Rotation & Indexing

Further update. I've been comparing toolpath methods. I've carving chess pieces for a King and Queen out of a pine 2x2. I carve one with conventional 3D finishing using a raster toolpath. Machine time was 60 minutes.

I took the same project and used Milo's spiral continuous turn technique. This time the machine time was 13 minutes, and the piece had a better finish. (Bottom piece)
If you have been frustrated with the slowness of rotary work please try this technique.
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

Leo
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### Re: How To: Continuous Rotation & Indexing

Randall - once again thank you.

I need to put my rotary axis on the machine and play around with it.
Imagine the Possibilities of a Creative mind, combined with the functionality of CNC

SteveNelson46
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### Re: How To: Continuous Rotation & Indexing

It works great. Even with twists and modeled shapes. I'll post the final project as soon as it's complete.
Attachments
Steve

tcoplin
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### Re: How To: Continuous Rotation & Indexing

I have been having difficulty with the Rounding toolpath gadget so I tried the Continuous Rotation & Indexing method referenced here. I wanted to cut a piece of test stock 1.4 inch square with a point to point diameter of 1.98 inches to a final diameter of 1.0 inch. Thus I calculated the cut depth would be 0.99 - 0.5 = 0.49. I used a 1.5 inch surfacing bit. It cut my stock down to a 0.5 inch diameter and left a slight spiral groves rather than completely smooth. Trying to figure out what I have done wrong.
Attachments

Rcnewcomb
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### Re: How To: Continuous Rotation & Indexing

It cut my stock down to a 0.5 inch diameter
What was your process to ensure the bit was Z-zeroed to match the center of the cylinder?
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

tcoplin
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### Re: How To: Continuous Rotation & Indexing

I Z-zero first on the surface of the tail stock, move the spindle to the left of the tail stock then go to zero. Then I move the bit tip to -0.522 and Z-zero. 0.522 is the distance from the tail stock surface to the center point.

Rcnewcomb
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### Re: How To: Continuous Rotation & Indexing

Look towards the end of the G code file. (You can use Notepad to look at it.) What values do you see for Z?
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

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