Not cutting flat bottom pockets in round stock

[Guerra Cues]

Hello folks,

I have been using the 4th axis for very simple projects for a while, but now I am starting to do some inlay work.

So here is a picture of what I am working on, maple and the ivory inlays. I cut a test curly maple piece and did the pockets.

I would like to know if there is an easy way to cut the pockets and automatically having it indexed. There is a trapezoidal variance between the part and the pocket since while the pocket is being cut, specially the circle, the 4th axis is moving instead of being static.

Let me know if I make sense or if you guys need me to explain in another way.

http://i272.photobucket.com/albums/jj164/bestkites/A80A3109-7B7C-43B3-B6E0-9C82652AC778-12113-00000CB49F262ADE.jpg

[steve_g]

Tony

I had the same experience... inlays cut flat don't fit nicely into pockets cut in the round. For my project I landed up holding the part in the indexer but cutting in normal X,Y,Z mode. Hope that makes sense.

SG

[Guerra Cues]

Tony

I had the same experience... inlays cut flat don't fit nicely into pockets cut in the round. For my project I landed up holding the part in the indexer but cutting in normal X,Y,Z mode. Hope that makes sense.

SG

Steve,

Can you give me the steps?

The other thing I was thinking about trying is to create a new flat file (not wrapped job setup), then once I calculate the toolpath use the indexing post processor but still I am not sure if it would do the trick.

I did a test run (air cut) and it did not look like it was going to work.

The inlays are 0.030" thick and 0.120" tall.

If you feel it would be better for you to give me a buzz and talk to me for a few minutes you can call me at 209-482-7768.

[steve_g]

A flat file is exactly what I meant... I just left it in the indexer as a convenient hold down method. Don't use the indexer PP

SG

[Guerra Cues]

A flat file is exactly what I meant... I just left it in the indexer as a convenient hold down method. Don't use the indexer PP

SG

That's a challenge. I was hoping that I did not have to do a MB command. That almost beats the purpose of having an indexer since I could have bought a manual tailstock and headstock and do it that way. Also if I use a MB command and since I will have different inlay sizes it's almost impossible to guarantee that the pockets are being cut with an exact distance apart from each other. This almost beats the purpose of having a CNC, might as well buy a Gorton pantograph.
There has to be a way to do this....
I was going to pull the trigger on a full blown version of Aspire and I am not sure if I am going to spend a couple of thousand on it now.

[Brady Watson]

Your issue has NOTHING to do with CNC, PartWorks or Aspire. It is an attribute of turning in the round that you cannot avoid with the toolpath strategies you have selected.

The simplest and most direct approach is to use a drilling strategy, with the appropriately sized bit. You can pocket out as you are doing now, and then use an end mill to drill cylindrical walled circles. If I were doing it, I would either order a custom diameter tool, or modify the circular portion of the inlay to fit into a standard diameter tool.

You can use the Indexer post processor...but you have to stop whining. :)

-B

[Guerra Cues]

Your issue has NOTHING to do with CNC, PartWorks or Aspire. It is an attribute of turning in the round that you cannot avoid with the toolpath strategies you have selected.

The simplest and most direct approach is to use a drilling strategy, with the appropriately sized bit. You can pocket out as you are doing now, and then use an end mill to drill cylindrical walled circles. If I were doing it, I would either order a custom diameter tool, or modify the circular portion of the inlay to fit into a standard diameter tool.

-B

Hello Brady,

Thanks for your input.

Would you be so kind and tell me what would be the steps?
I would think this should be a very simple process but it looks it is not. Can't I use the same end mill for that process?

[myxpykalix]

Tony,
I think essentially what you want to do is inlay your part into your round piece correct? Based on your picture the indexer would not be rotating to make this cut but along a straight axis.

What he is saying is, it doesn't matter if the indexer is holding it, or you had a jig on the table, the cutting toolpath is the same.

What i seem to understand from you is you think the underlying female hole should be curved to the same profile as the round surface, am I right?
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Another way i read it is you think the distance is somehow skewed because of the curved surface?

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The way it works is the computer looks at this as a flat file and instead of Y moves it rotates B and you still wind up with the exact distances between parts.
maybe i don't understand:confused:

[Brady Watson]

Use the same file you used when setting up to pocket the 1st time. Except - draw circles by themselves where the circular pockets are. Group them together and create a drilling toolpath. I don't know what size your trapezoidal round pockets are now, so I can't recommend a drill/end mill diameter. You want to drill JUST those circular pockets to clean up the trapezoids. No you cannot use the same bit. It will have to be the same diameter as the circular pockets. This is why I said you may need a custom tool or have to change the size of your inlay parts slightly to match the dia of a standard off the shelf tool.

-B

[Guerra Cues]

Well guys,

I love this place...
After I talked to Christian here is what he suggested:

- Create a unique toolpath for each of the pockets (so 6 toolpaths)
- Resize the eight area to stock eight
- Align objects in center of the material
- Recalculate all toolpaths
- Output all visible toolpaths to one file and save it
- Edit the file and find the name of the toolpath and add the MB,60, then 120, 180, etc.

I am going to give it a test run. I will post the results back :D

[Guerra Cues]

Just an update... All suggestion given above by Christian from Shopbot worked like a dream. The drilling suggestion is really good for other projects. I will post a picture of the final product. Thanks for all the help guys.

[Brady Watson]

Great! Glad you got it worked out.

Thanks for letting us know.

-B