Path: Toolpath for operations smaller than tool width.

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reet
Posts: 9
Joined: Sun May 07, 2023 5:26 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by reet »

GeneFC wrote: Sun May 07, 2023 11:36 pm I played with this file for a while, using a very recent version 0.21. (Good move to update!)

I was able to use the single-edge function of the Profile operation to pattern the steps with minimal extra moves.

The only problem is that each step needs to be set up exactly for the start height and the finish height.

If this is a repetitive job then it is worth setting up. If it is a one-timer I would just go with the full orbit profile and get on with life. 8-)

Gene
Thank you. I was having trouble getting the single edge profile to work, but I think I've got it now with the description in your reply as well as @bmsaus4ax.

This is a part that I would like to have a well set up tool path, so if I need another clamp I can just load up the g-code and cut out another, so in that sense it is not meant to be a one-off process. It is also a good learning process for me, to learn how to "do it right" vs "this sort of works". :)
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stair clamp v2.FCStd
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xemul
Posts: 394
Joined: Tue Mar 21, 2023 9:35 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by xemul »

I am not sure if the presented sequence of operations is safe for the tool
(material, feedrates and spindle speed are not specified, so StepDown = OpToolDiameter up to you).
stair clamp v2_adaptive.FCStd
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knipknap
Posts: 115
Joined: Sat Mar 05, 2022 1:21 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by knipknap »

Has anyone managed to make this fully work with a ramp-in?

All the solutions proposed here generate a path without ramp-in helix. Even trying to use a dress-up I was not able to create it, the dress-up has no effect when using helix mode.
knipknap
Posts: 115
Joined: Sat Mar 05, 2022 1:21 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by knipknap »

I finally figured it out. I used the following approach:

- Select the face of one stair.
- Use Adaptive clearing
- Extensions -> Extend the path enough to fit at least two tool diameters.
- Select "force clearing inside-out "

Repeat for each of the stairs.
xemul
Posts: 394
Joined: Tue Mar 21, 2023 9:35 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by xemul »

An in adaptive op's helix ramp is created for inner faces or by setting the "ForceInsideOut = True" property. Is this your case?
knipknap
Posts: 115
Joined: Sat Mar 05, 2022 1:21 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by knipknap »

Yes, but you have to keep in mind to increase the extension by at least 2*tool diameter (or so, actually 1.5 seems to be enough). Otherwise "force inside out" has no effect.
xemul
Posts: 394
Joined: Tue Mar 21, 2023 9:35 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by xemul »

For adaptive op's SlotWidth = OpToolDiameter + HelixDiameterLimit.
The required slot width for the profile op depends on the height of the workpiece (and therefore on the required slot depth), on the material to be machined, on the possibility of chip removal, on the use of a coolant, on ...
A deep slot in (mild) aluminum is not an easy task.
In your case, I would first make a workpiece with the required dimensions along the flat faces (yes, 3 rearrangements of the workpiece; probably need to leave some tags on bottom edges for a clamps), and only then I would process the steps (4th rearrangement).
jbraun
Posts: 253
Joined: Fri Sep 18, 2020 5:41 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by jbraun »

If there's a bunch of stock to remove one approach would be pockets with extensions. 2mm tread with 3mm tool. Each tread = one op.
I work mostly with soft materials so this may be (and probably is) a poor choice for metals.
stairtread2.png
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xemul
Posts: 394
Joined: Tue Mar 21, 2023 9:35 pm

Re: Path: Toolpath for operations smaller than tool width.

Post by xemul »

For me, the main advantage of adaptive op's is in keeping the climb/conventional cutting direction and predictable chipload, which allows me to set the optimal tool feed rate.
For other operations, this is conditionally possible only for the offset mode and only when starting from the open edge of the workpiece. If the lead-in occurs over the entire area of the tool (and, therefore, the first pass is performed with StepOver = 100%), then it is necessary to reduce the cutting speed for the entire operation as a whole. Given this circumstance, adaptive op's are generally more time efficient.

??? Feature request: is it possible to take into account the actual length of cut relative to the specified StepOver and reduce the feed rate accordingly?
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