## Multiple datum planes and sketches

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scrungy_doolittle
Posts: 105
Joined: Thu Jun 21, 2018 11:15 pm

### Multiple datum planes and sketches

I't been a while since I have been on here, and even longer since I have worked on my old ring design. After much cogitating, I think I can do the following: but am not sure where to start.
1. Create 10 datum planes attached at the same edge (think leaves of a book)
2. Place slightly different sketches on each of the datum planes, all of which have a length contraint from the common edge, such that I can hopefully change just 1 dimension and have all the different sketches on the dataum planes, move.

So to conceptualize this, say the 10 datum planes are attached by their right hand edge. I create a small flattened oval on dataum plane 0, and set a distance constraint from the bottom of that oval to the right hand edge. I then create a slightly wider oval of the same thickness on dataum plane 1, and set the same constraint on it. I repeat this for all 10 datum planes.
I think link these constraints with an equality so that if I change the length constraint number, all 10 sketches will move.
Then I can set the planes for various angles, set a length constraing, and do an additive pipe to make a 180 degree segment of a ring.
SOOOO
1. How do I create 10 dataum planes, all connected at one edge, and all n the same plane.
2. How do I put a sketch onto one plane?
3. How do I copy that sketch to the next plane, and set a length constraint from the common edge.
4, How can I alter the second sketch without affecting the firs sketch, but being able to see the the first sketch so I can used it as a construction guide for the second sketch and so forth.
Watched a couple of you tube tutorials, but still does not make a lot of sense.
TheMarkster
Posts: 1061
Joined: Thu Apr 05, 2018 1:53 am

### Re: Multiple datum planes and sketches

If I understand you I don't think you need datum planes. Just attach all 10 sketches to the plane, for example the xz_plane. Then set their attachment offset to your length constraint. Sketch 0 would be at 0 z offset. Sketch001 would be at Sketch.Constraints.length * 1, Sketch002 at Sketch.Constraints.length * 2, and so on up to Sketch009 with z attachment offset at Sketch.Constraints.length * 9. Then when you change the length constraint in Sketch the other sketches will move in unison.

You can easily hide the sketches except the one you are working on.

I am attaching a template file with 10 sketches positioned as I have described. Each sketch has a circle in it so it shows up in the 3d view. You can remove the circle in each and replace it with your own elements. The first sketch has a construction line constrained to "length" for the purpose of having a constraint to work with. You can move that construction line out of your way if need be, but don't delete it.

Don't rely on block constraints this time.
Attachments
pretty_sketches_all_in_a_row.FCStd
scrungy_doolittle
Posts: 105
Joined: Thu Jun 21, 2018 11:15 pm

### Re: Multiple datum planes and sketches

TheMarkster wrote:
Mon Jul 15, 2019 3:52 am
If I understand you I don't think you need datum planes.

Unfortunately you do not understand. These are sketches all in a row, but they are not tiltable to form an arc.
The goal is to have something like this:

_ \./_ where the lines are sketches oriented like a book, so I can create a 180 degree half ring, that is made up of slightly different sized sketches.
like a book with 10 leaves. on each leaf is a slightly different sketch, with each leaf at a different angle. So that an additive pipe will create a 180 degree half ring.
The attached file shows a ring (which is not usable ), because of the way it was done. The problem of course are the sharp flats on the crown of the ring. Ignore the projecting portion of this ring, and just visualize the ring body only.

There is a sketch also.
Enable the sketch.
Now envision the white lines as datum planes, or flat plates, that intersect and cut through the ring. You can see that each datum plane would have a different cross section of the ring.

What I want to do, is create datum planes connected at the origin, just like the lines are, be able to lay them all on top of each other (i.e. change their angles to 0. Then one at a time, create the proper cross section on each datum plane, so that they can be re-angled, and an additive pipe
done, following them. A bonus would be to have all of the cross sections be adjustible from the edge of the plane, so I can create say a 7.5 sized ring, or a 5, or a 9 or whatever, by just changing one dimension.
And for each cross section, that dimension would be between to bottom edge of the sketch and the origin.

Attachments
explain_attempt.FCStd
chrisb
Posts: 19749
Joined: Tue Mar 17, 2015 9:14 am

### Re: Multiple datum planes and sketches

papyblaise
Posts: 762
Joined: Thu Jun 13, 2019 4:28 pm
Location: France

### Re: Multiple datum planes and sketches

Hello
if you need a progresiv profil , only 2 sketch are inough +1path (red one)
if you are more section you need one at the begining, one on midle , one at the end , and one path of each
to create the intermediat draw it on XY plan (for exemple) and change placement with the appropriate angle (gold)
Attachments
jolie ring.FCStd
jolie ring.PNG (44.67 KiB) Viewed 279 times
TheMarkster
Posts: 1061
Joined: Thu Apr 05, 2018 1:53 am

### Re: Multiple datum planes and sketches

phpBB [video]

use the point at the end of the 2 lines, which you should convert to construction mode, as the new origin for each sketch. Then when you change the offsets in the spreadsheet the sketch should move in that direction. You can change the angle in the offset placement, but just remember what it was so you can change it back when needed.

I don't think I've ever seen a model made in this manner, but I encourage you to try it if you have a vision for how it will work.
Attachments
pretty_sketches_all_at_an_angle.FCStd
scrungy_doolittle
Posts: 105
Joined: Thu Jun 21, 2018 11:15 pm

### Re: Multiple datum planes and sketches

TheMarkster wrote:
Mon Jul 15, 2019 5:48 pm
phpBB [video]

use the point at the end of the 2 lines, which you should convert to construction mode, as the new origin for each sketch. Then when you change the offsets in the spreadsheet the sketch should move in that direction. You can change the angle in the offset placement, but just remember what it was so you can change it back when needed.

I don't think I've ever seen a model made in this manner, but I encourage you to try it if you have a vision for how it will work.
Opened the file.
what is this "Spreadsheet...." never have seen that before. How did you add it? These are boxes rather than circles, when I pull it in.
So now, assuming that I want to do a loft... I created a sketch that is a 5mm circle, and it hits the boxes at the correct spot. I go to sweep (additive pipe) and it lets me add the available profiles to the sweep. I leave the 5mm circle in the available profiles, and click on create solid.
click on sweep path and it grays out.

So given your file, how would I make this sweep through the squares to create a shape that is the cross section of the sketches, and connects them.
scrungy_doolittle
Posts: 105
Joined: Thu Jun 21, 2018 11:15 pm

### Re: Multiple datum planes and sketches

papyblaise wrote:
Mon Jul 15, 2019 3:49 pm
Hello
if you need a progresive profil , only 2 sketch are inough +1path (red one)
if you are more section you need one at the beginning, one on middle , one at the end , and one path of each
to create the intermediate draw it on XY plan (for example) and change placement with the appropriate angle (gold)
The point of the 10 planes is to control the progression. 3/4 of the ring should be the same thickness, and then it begins to widen out.
If you look at the original.
I have modified the cross section of one of the sketches. Essentially what you have in the first sweep is what I need, except I need a bunch more sketches, and they need to be shaped like the one I did (a comfort ring profile). More importantly, how can I control the "rotation" of the sketch?
So for starters I have modified one sketch. I need 4 copies of it along the curve and the other sketches being non incurvate..
So I have accomplished part of this. hie everything other than sweep mirror 1, There are two end points, now I want to take the sketch under the first sweep, copy it 3 times and place them on the curve.
Basically Jolie_4 is what I want, but I want to have essentially about 4 copies of sketch and 4 copies of Sketch002, placed approximately equal spacing around the ring. Then I can go tweak the outlines to get the curve I want.

Eventually, I'll want to re-do the sketches with cubic splines. When you enable both sweeps, you will notice at the thing part of the ring, it starts diverging. About where I drew sketch 6 is where I want to to start diverging outward. The think I will then need to know, is how I can move the sketches back and forth along the sweep to tweak the profile the way I really want it to be tweaked.
Attachments
jolie_4.FCStd
scrungy_doolittle
Posts: 105
Joined: Thu Jun 21, 2018 11:15 pm

### Re: Multiple datum planes and sketches

bump
openBrain
Posts: 2410
Joined: Fri Nov 09, 2018 5:38 pm

### Re: Multiple datum planes and sketches

Isn't using Placement dialog enough to get what you want ?