Rectangular scoop

[Zelbar]

Fairly new to Vcarve Pro. Trying to find a way to just do a simple rectangular scoop (as per attached picture) in a quick, efficient way.
A 1" thick rectangular piece of wood scooping down to 3/4" in the center.
Can't find any information online and all my attempts are not working out.
Any directions would be greatly appreciated.

[scottp55]

Something like this?

[FixitMike]

To expand on Scott's suggestion: The tool used is a 1/2" end mill, the vectors for the toolpath are spaced 1/8" apart. A ball end tool will leave grooves.

You can also use the Moulding toolpath, but the execution is more complicated.

[scottp55]

Have a minute longer now:)
Draw polyline/copy(Control CV)/Move Relative the amount of stepover for the biggest bit (and finish wanted)/in Node Edit change Start Point to Opposite end of first line/G (Group)/ then linear array with Gap same as the amount second line was moved...change those to a second layer as shown in .crv(IF cut depth is deeper than your .25"..you can have the first two lines cut in appropriate pass depths..then run second Toolpath at full depth, as it's only cutting the stepover)/ U ngroup all, and check the Use Vector Order...PREVIEW so it shows cutting sequentially!!.
Then have first two lines cut Above the Copy/Arrayed toolpath, and Combine the 2 toolpaths,AFTER test cutting first 2 lines.
Alternating Start Points in this particular case saves a lot of Air Time, and first two cuts will give you a good idea of cut quality.
Sounds confusing, but it's not after 2-3 times

[Zelbar]

Awesome, thank you so much. I did not even think about the fluting path as I had never used it before as most the the stuff I do is nowhere like this.

I did a first test cut and am just doing some adjustments to optimize the process.

Again thanks, learned something new today.

[FixitMike]

Scott's expansion on the method is definitely a more elegant solution for the most efficient way to make the cut. It eliminates many unnecessary passes. An alternate to making the first pass a separate toolpath (since the scoop goes to the edge of the material) is to make the first pass off of the material and then proceed into the material with full depth passes. Draw the first vector off of the edge and then proceed into the material.

Some things to note:
1. One element of using the fluting toolpath for this cut is that there will be a flat the width of the bit at the bottom of the flute. In this case, I doubt very much it will be noticeable, but one should be aware that that it will be there. It could be a problem if the scoop were to be much narrower.
2. The vectors drawn locate the center of the bit path. So the actual area cut will be larger on each side by the radius of the bit.

[4DThinker]

A close look at the posted image the cut appears to be scooped (bowed) in both the X and Y directions. As if the scooped out area is a section of a sphere rather than a cylinder.
You could accomplish this with the fluting toolpath but the vectors that run in the X direction would need to stretch out in the middle of the run. Essentially starting farther and farther from the left/right edges the closer they are to the center of the width. Example below.

[FixitMike]

[quote="4DThinker"]A close look at the posted image the cut appears to be scooped (bowed) in both the X and Y directions. As if the scooped out area is a section of a sphere rather than a cylinder.
You could accomplish this with the fluting toolpath but the vectors that run in the X direction would need to stretch out in the middle of the run. Essentially starting farther and farther from the left/right edges the closer they are to the center of the width.]

If this is the situation, one can use flute vectors that are radial. Here are some examples. Note that the chair vectors overlap in the center so that there is a center ridge.

[SteveNelson46]

There are a lot of posts on this subject. A quick search for "chair seat" will yield quite a few techniques and examples.

[Zelbar]

The fluting passes worked great. I already have thirty some of them done.

Thanks everyone for the help.

[scottp55]

GLAD you're good and going!
When you've got a few minutes, play with the Fluting Toolpath.
Circular array/different bits/Trim Vectors/etc.
Powerful tool...almost as much so as the Forum!
All pics used Fluting toolpath somewhere.
scott