Rest Machining vs Modeling Resolution

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stephenpinn
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Rest Machining vs Modeling Resolution

Post by stephenpinn »

New to the forums so my apologies if this has been addressed, I did search but did not find anything relevant.

I have been told that Model Resolution settings have little if any affect on toolpaths, that the real effect is on the rendering within aspire. I was wondering if Model Rendering values affect the vectors created when rest machining?

Thank you in advance for your guidance

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highpockets
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Re: Rest Machining vs Modeling Resolution

Post by highpockets »

Rest Machining is good of speeding up the machining of detailed areas of a model, but it won't add anymore detail to a model that wasn't to begin with. The resolution and detail of a model are set when the model is created
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stephenpinn
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Re: Rest Machining vs Modeling Resolution

Post by stephenpinn »

thanks John and that is what I was familiar with. I raised the question with Rest Machining since you generate the component and the sketch based upon the toolpath. If the render is more accurate is it possible for the vectors created from the toolpath based component be more accurate?

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highpockets
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Re: Rest Machining vs Modeling Resolution

Post by highpockets »

I see what your asking now. I'd say the higher your Preview Simulator Quality setting the better the detail would be for the rest machining.
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Rcnewcomb
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Re: Rest Machining vs Modeling Resolution

Post by Rcnewcomb »

Model Resolution settings have little if any affect on toolpaths
I disagree agree with that statement.

Outrageous example to prove a point:
1. Create a new project in Aspire: Single-Sided, 48"x96"x1" at Standard Resolution
2. Draw a circle somewhere with a 1 inch diameter
3. With the circle vector selected go to the Modeling tab and choose "Create Shape from Vector Outlines", dome profile with a 25 degree angle, Apply/Close
4. Select the component and click on the icon for "Create Vector Boundary around selected components" -- notice the new vector doesn't match your original circle vector
BadResolution.JPG
The resolution of the vectors for rest machine will be affected by the model resolution.

But....
There is no benefit to going overboard on resolution.

Model Resolution Number of Pixels
Standard 1,000,000
High 2,000,000
Very High 4,000,000
Extremely High 8,000,000
Maximum 16,000,000

You can use those numbers to see how much resolution each pixel will give you.
Now compare that to the stepover you are using on your finish pass, and choose a resolution that makes sense.
- Randall Newcomb
10 fingers in, 10 fingers out, another good day in the shop

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dealguy11
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Re: Rest Machining vs Modeling Resolution

Post by dealguy11 »

There are 2 places in Aspire that deal with resolution. The first is "Modeling Resolution" on the Job Setup panel. It absolutely DOES have an effect on toolpaths. As Randall pointed out, it controls the number of pixels in the job, which is a fixed number regardless of the size of the job. More pixels per square inch equals greater detail possible when modeling (but only when creating the model - you can't get more detail out of a model that was created with low resolution). So a lot of pixels in a small area can increase both the detail available and also the smoothness of the edges of the model - the edges are mostly where you'll see the difference. It is true that if you use a bit that is larger than the details in the model, then the additional detail doesn't do you much good, so there is a tradeoff. The difference in edge detail, and the elimination of pixelation at the edges, can be a big deal in some models.

The other place that deals with resolution is Preview Simulation Quality on the Toolpath pulldown. It does not have any effect at all on toolpaths. It's purpose is to increase the amount of detail that's shown on the screen in toolpath previews...if your computer can handle the highest level of detail, then I'd set it there.
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Re: Rest Machining vs Modeling Resolution

Post by TReischl »

This resolution thing always drives me a little nutzoid.

Going to do some maths here, and if someone spots a mistake, please point it out!

Let's start with the idea that we are going to make a model in a 10 inch X 10 inch square.

We are going to set the modeling resolution to standard (1,000,000 pixels). That means there are 1 million pixels packed into that square.

There are 100 square inches in the 10 X 10 square.

So, with a little high level mathematics we have 1,000,000 / 100 which equals 10,000 pixels per square inch. So far, so good!

But what does that mean in terms that are understandable? I do not have a feel for what 10K pixels in a one inch squares really means. Sooooo......

To get how many pixels per lineal inch (along one side of that square) we take the square root of 10,000 which my trusty calculator says is 100. So we have 100 pixels per inch. Or, each pixel represents .010 of an inch. Now that means something to me! I know how big the darn pixels are! Well, on a 10 X 10 model anyhow.

To understand the effect, let's now change the model to 20 X 20. 1,000,000 / 400 sq inches = 2,500 pixels per sq inch.
And then. . . square root of 2,500 = 50 pixels per side of the 1 inch square so the "resolution" of the pixel is .020 inches per pixel.

This is about the only way that I can digest the concept of "resolution".

From the above it is apparent that as your model size increases, one needs to increase the resolution or suffer the consequences Randy mentioned above.

Most of us are always looking to get better looking cuts. But a simple fact of life is that a ball nose cutter does not create a sharp corner and that fact causes models to be a little less than "sharp". One thing I always keep in mind is the intended viewing distance of the model. There is no point in using a .031 ball nose cutter on a model that is typically viewed from 10 feet away. Of course, since we have our faces right on top of the model when we cut it, we seem to think that we have to have all these sharp corners and tiny details. That can make a person a little less than sane after a while. :shock:

Increasing resolution as the model gets larger is very important. As Randy showed above, bad things happen if you do not. If you create a 1 inch square on a 96 X 48 sheet, then create a component of that square with the resolution at 1M pixels, the component will actually be about .086 too big in X and Y. That is a lot! BTW, as the square increases in size, so does the amount of error.
"If you see a good fight, get in it." Dr. Vernon Johns

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