Evening Sir.
tigermm wrote: ↑Sat Jul 24, 2021 12:10 am
... I'll add the cylinder in the middle and profile it first to give clearance for the taper cut. Does this need to be part of the same body, or will a second body suffice? ...
No. It does not, so long as when you add the cylinder to the same Job object, its placement is correct in reference to the rest of the actual part. Jobs support multiple base models.
tigermm wrote: ↑Sat Jul 24, 2021 12:10 am
... Now my question is..... how did you get that when none of your parameters look much different to what I tried? ...
I apologize. I have been with the project for only a couple of years. I still don't think it is as intuitive to use as it could be, and it is not as well documented as it needs to be. That said, I am partially to blame since I am a contributor to the project.
My recommendation is that you continue to use the forums for assistance. There are many great users that will help other users seeking assistance. Also, I recommend comparing your settings for the 3D Surface op with those settings in ops presented to you here in this thread as a learning process - go setting by setting.
tigermm wrote: ↑Sat Jul 24, 2021 12:10 am
... Stepdown of 0.95 instead of 1.00, why was that? ...
The 3D Surface and Waterline operations are unique from all others because they work with meshed versions of the models - this means all faces are converted to triangles for much simpler interaction mathematically. For this reason, 3D Surface can produce some unwanted artifacts in the paths because of the triangulated curves. I had some artifacts appearing in the paths generated, so I began adjusting certain properties (settings) in an attempt to eliminate the artifacts as best possible. You wanted 1mm step downs, so 0.95 is likely to be acceptable if it removes some unwanted artifacts in paths.
tigermm wrote: ↑Sat Jul 24, 2021 12:10 am
... Final depth of 41, is that so there is less left to trim off due to using a ballnose mill? Or to stop it trying to machine the whole bottom of the pocket? ...
Same purpose as previous question - attempting to remove artifacts in paths. Honestly, this 1mm drop to -41.00 mm did not remove any artifacts; therefore, it could likely be changed back to your original -40.00 mm.
tigermm wrote: ↑Sat Jul 24, 2021 12:10 am
... What exactly does the Sample interval do? (from the wiki: Set the Sample Interval used for the OCL scan) ...
Great question. Sample Interval could also be labeled Sample Resolution. This value is the spacing at which the cutter (tool bit) is dropped down to the model until it makes contact at any point. The smaller the value, the more accurately the cut will follow the true curve of a path (given a proper tool bit for the curve to be cut). Reference the last attached image. The two brown curves are identical. The green Sample Interval is 10mm and the blue is 5mm. You can see the blue better fits the curve. It is very worth noting the the smaller the sample interval the greater the processing time for the operation. This is also true of step down and step over values. Decreasing them makes the computation time grow nearly exponentially. Also, you can have a nice very small tool bit and a large sample interval, and your cut will not be smooth because the large sample interval will not provide a sufficiently dense sample of the curve being cut.
tigermm wrote: ↑Sat Jul 24, 2021 12:10 am
... I see you've used Multipass but not used a depth offset, do they not need to both be specified? ...
The Multi-pass setting essentially converts the 3D Surface into a 3D Pocket. Using Multi-pass was me not paying attention!
As far as I know, the Depth Offset is used to leave stock, like a roughing pass. Use it if you need that.
tigermm wrote: ↑Sat Jul 24, 2021 12:10 am
... Sorry for so many questions but I'd love to understand the way to do this in future rather than asking someone else to help me every time.
Cheers,
Mike.
One of the quotes I remember most from my dad during my high school years is, "Son, you're never going to learn anything if you don't ask questions." I say this respectfully and as encouragement. FreeCAD is a great piece of software. We, the FC community, are both learning and improving this project together. Keep learning!
I attached an updated file version with the two faces in a single 3D Surface op based on the taper op of my earlier version, but with Single-pass and a 0.75 mm step down. The two faces have different 3D Surface settings needs and should likely be separated, but I combined them just to show the effect. That top face is mostly flat, so the step over used is likely too dense for what you are requesting. Reference the first three images.
Have a great night, Mike!
Russell