How To: Continuous Rotation & Indexing

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

Post by Rcnewcomb »

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
    Screen Shot 2022-09-12 at 3.47.01 PM.png
  2. Select the spiral layout gadget.
    Screen Shot 2022-09-12 at 3.48.17 PM.png
  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.
    Screen Shot 2022-09-12 at 3.49.36 PM.png
    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
    Screen Shot 2022-09-12 at 4.12.10 PM.png
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
(649.86 KiB) Downloaded 136 times
- Randall Newcomb
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another good day in the shop

Jimcad
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Re: How To: Continuous Rotation & Indexing

Post by Jimcad »

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. :wink:

Jim

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Re: How To: Continuous Rotation & Indexing

Post by PaulB »

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.

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SteveNelson46
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Re: How To: Continuous Rotation & Indexing

Post by SteveNelson46 »

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

Post by Jimcad »

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

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Re: How To: Continuous Rotation & Indexing

Post by Rcnewcomb »

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.
Screen Shot 2022-09-13 at 4.57.56 PM.png
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.
Screen Shot 2022-09-13 at 5.02.06 PM.png
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

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Leo
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Re: How To: Continuous Rotation & Indexing

Post by Leo »

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

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Rcnewcomb
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Re: How To: Continuous Rotation & Indexing

Post by Rcnewcomb »

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)
KingQueenIMG_4193.jpg
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

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