Profile ... with a finishing pass

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CandL
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Joined: Thu Oct 29, 2020 6:41 pm

Profile ... with a finishing pass

Post by CandL »

I think I might know how to do what I want but looking for validation. (The most recent video seems to be, sliptonics dressups which was 4 years ago and did not have a profile dressup ... this statement is NOT intended to be critical, I am very grateful for all the work)

Here is the problem... cutting out a foot profile from Oak. It will take 3 passes at a step down of 1 tool dia. This will leave marks in the Oak, so I want to leave say 0.01" on the profile and then do one full depth pass to remove that 0.01"

FootProfile.jpg
FootProfile.jpg (73.34 KiB) Viewed 1735 times

As you can see I already have a dress up for the tabs.

Do I now add a new Profile dress up? If so is the process:

- In the actual profile path use extra offset = 0.10
- in the profile dress up set extra offset to 0.00

My concern here is order of operations .... my guess is what I just said will not give me good results ...ie the tabs will be gone.

Should the order be
1) Profile with offset
2) Offset profile (taking full depth cut)
3) Tabs added last

In a similar vein the pocket ... I am fine hogging out the majority with a 90 % step over to a depth within say 0.01 again and then doing a finishing pass 0f 0.01 with a 30% step over.... is this possible via dressups? Or is this best done with a completely separate toolpath?

Try to understand FreeCad Modeling philosophy.

Thanks for the insights.
GeneFC
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Location: Punta Gorda, FL

Re: Profile ... with a finishing pass

Post by GeneFC »

I have not used any sort of profile dressup, but here is a kludge I have used successfully.

Define a new (fake) tool that is 0.01" larger in diameter than the tool you plan to use.

Use that "fat" tool in FreeCAD to create the rough pattern, just as before. The g-code should look the same as it does now, just slightly larger.

Now use the original tool in FreeCAD to create the finish pattern, including tabs or whatever else you need.

In the shop the same (original) physical tool is used for both operations. You might need to strip out a tool change operation in the g-code if it causes a problem.

Works just fine in my experience, and the shop time is exactly the same.

Gene
Russ4262
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Re: Profile ... with a finishing pass

Post by Russ4262 »

Afternoon.
Here is my take on your question. I simply created a demo file based on your image. See attached. I used adjustments to the offsets and heights/depths to make the included paths. I also used the `Copy From` feature of the Tag Dressup to place finish tags in same/close location to roughing tags for the Profile ops.

Have a great day.

Russell

Code: Select all

OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.21.29434 +11 (Git)
Build type: Release
Branch: master_prs
Hash: 7007fc82c3e7a53608d47fd9c2f65d22fb23b5e3
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.2
Locale: English/United States (en_US)
Installed mods: 
  * FC_SU
  * PathExp
  * Z_MacroStartup
Attachments
rough and finish.FCStd
Example file
(68.32 KiB) Downloaded 45 times
CandL
Posts: 85
Joined: Thu Oct 29, 2020 6:41 pm

Re: Profile ... with a finishing pass

Post by CandL »

GeneFC wrote: Fri Jul 15, 2022 9:18 pm I have not used any sort of profile dressup, but here is a kludge I have used successfully.

Define a new (fake) tool that is 0.01" larger in diameter than the tool you plan to use.

Use that "fat" tool in FreeCAD to create the rough pattern, just as before. The g-code should look the same as it does now, just slightly larger.

Now use the original tool in FreeCAD to create the finish pattern, including tabs or whatever else you need.

In the shop the same (original) physical tool is used for both operations. You might need to strip out a tool change operation in the g-code if it causes a problem.

Works just fine in my experience, and the shop time is exactly the same.

Gene
A nice simple solution for the profile problem ... I like it.
CandL
Posts: 85
Joined: Thu Oct 29, 2020 6:41 pm

Re: Profile ... with a finishing pass

Post by CandL »

Russ4262 wrote: Fri Jul 15, 2022 10:45 pm Afternoon.
Here is my take on your question. I simply created a demo file based on your image. See attached. I used adjustments to the offsets and heights/depths to make the included paths. I also used the `Copy From` feature of the Tag Dressup to place finish tags in same/close location to roughing tags for the Profile ops.

Have a great day.

Russell

Code: Select all

OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.21.29434 +11 (Git)
Build type: Release
Branch: master_prs
Hash: 7007fc82c3e7a53608d47fd9c2f65d22fb23b5e3
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.2
Locale: English/United States (en_US)
Installed mods: 
  * FC_SU
  * PathExp
  * Z_MacroStartup
I like the 'Copy From' need to add that to the bag of tools.
CandL
Posts: 85
Joined: Thu Oct 29, 2020 6:41 pm

Re: Profile ... with a finishing pass

Post by CandL »

Both solutions create a duplicate (although modified) tool path ... which is very shop friendly. Thank you for both responses.

But I was under the impression "dressups" were intended to solve this kind of problem, am I mistaken?
GeneFC
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Location: Punta Gorda, FL

Re: Profile ... with a finishing pass

Post by GeneFC »

CandL wrote: Sat Jul 16, 2022 12:27 pm But I was under the impression "dressups" were intended to solve this kind of problem, am I mistaken?
Yes, but I am not aware that such a dressup exists at this time. I recall there has been some talk along those lines, but I do not believe it is yet implemented.

@Sliptonic could give a definite answer.

Gene
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sliptonic
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Re: Profile ... with a finishing pass

Post by sliptonic »

GeneFC wrote: Sat Jul 16, 2022 2:24 pm
CandL wrote: Sat Jul 16, 2022 12:27 pm But I was under the impression "dressups" were intended to solve this kind of problem, am I mistaken?
Yes, but I am not aware that such a dressup exists at this time. I recall there has been some talk along those lines, but I do not believe it is yet implemented.

@Sliptonic could give a definite answer.
Dressups modify a single operation tool path. In this case, you really have two. The initial 'roughing' pass that should use the extraoffset to leave a bit of material behind. And the second 'finishing' path that is at full depth and removes the extraoffset.

Both ops need to have the tags applied. So I favor Russ's solution.
Dressups were never intended to be applied to multiple ops at one time.
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sliptonic
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Re: Profile ... with a finishing pass

Post by sliptonic »

We're gradually refactoring the operations to take the path generation logic out to simpler and cleaner functions. Then the operations can use these 'generators' to build up more complexity.

Once we refactor the profile operation, I'd like to consider adding the feature to the profile operation to apply a finishing pass. I don't want to do that now because it just makes the refactoring more difficult.
memfis
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Joined: Tue Nov 15, 2016 7:58 pm

Re: Profile ... with a finishing pass

Post by memfis »

sliptonic wrote: Sat Jul 16, 2022 4:11 pm Dressups were never intended to be applied to multiple ops at one time.
And very in vain. A typical case where two such "overlaps" have to be combined is in the form of a dog bone + instrument approach and withdrawal.
I would recommend to the topekstarter to solve his local problem not to create a new tool, but to use the standard option when creating a "full-depth finishing operation" Extra offset, setting a negative value (or for roughing by setting a positive value). IMHO - 0.01 will not be enough for the stated purpose.
Снимок экрана от 2022-07-17 13-57-50.jpg
Снимок экрана от 2022-07-17 13-57-50.jpg (30.21 KiB) Viewed 1470 times
Also - 1\4 cutter and 1\4 depth step - jumpers will not save, there will be a lot of vibration on the lower passes and it will damage the side surfaces. Changing the depth of the pass for such applications should be made variable. And it would be wise to switch to a mill 1\8 with passage in the range of 2-2.5 mm, at the end of 1, then 0.5, then to a depth of 0.02-0.05, and then no need any jumpers - filings perfectly will hold the part.
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