Part/Draft constraint equivalents

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garya
Posts: 171
Joined: Tue Nov 20, 2018 1:00 am
Location: Ovando, MT, USA

Part/Draft constraint equivalents

Postby garya » Tue Mar 19, 2019 4:13 am

I'm trying to get more comfortable with Part and Draft WB by duplicating something I did with Part Design and Sketches.
Attached are two cut down files, one using PD and Sketch WB (Reamer_PartDesign_1.FCStd) and the other a partially done Draft (Reamer_Part_1.FCStd).

I'm wondering if anyone can give me some hints on the best way to get the Draft WB version laid out. As you can see from the sketch in the first file, it is constrained by positioning vertices at the intersection of rays at fixed angles with circles, plus angles between some of the sides of the polygon itself.

Problems I'm having:
1. How to lay out construction lines based on angles rather than trig computations to position the endpoint of the rays
2. I can line up one of the points on the lines with the construction, but when I go to move another point the whole polygon moves. Is there a way to keep the lines with "flexible length" so the endpoints can be positioned and they grow and shrink as needed?
3. How does one constrain two lines at a fixed angle?

Thanks for any clues.
Attachments
Reamer_Part_1.FCStd
(17.58 KiB) Downloaded 6 times
Reamer_PartDesign_1.FCStd
(10.86 KiB) Downloaded 6 times
chrisb
Posts: 18002
Joined: Tue Mar 17, 2015 9:14 am

Re: Part/Draft constraint equivalents

Postby chrisb » Tue Mar 19, 2019 10:58 am

Sorry for not being able to answer your question, except that a difference between Sketcher and Draft is that Draft does not have these nice constraints. I have iin turn a question: Why would you replace Sketcher with Draft? You can use Sketches in Part workbench as well.
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meme2704
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Re: Part/Draft constraint equivalents

Postby meme2704 » Tue Mar 19, 2019 11:14 am

Same note as Crisb, in addition, you use Spreadsheet since then, it is impossible for you to change anything
What a stupid idea that newbies have to want to freeze with spreadsheets :?:
garya
Posts: 171
Joined: Tue Nov 20, 2018 1:00 am
Location: Ovando, MT, USA

Re: Part/Draft constraint equivalents

Postby garya » Tue Mar 19, 2019 2:15 pm

chrisb wrote:
Tue Mar 19, 2019 10:58 am
Why would you replace Sketcher with Draft? You can use Sketches in Part workbench as well.
I wanted to understand how to use Draft better. Posts say some people prefer draft/part and others prefer sketch/part design. I wanted to understand the differences better and why one might choose to use one over the other. If it's simply a matter of preference, one ought to be able to accomplish the same thing either way, so I wanted to try that.
chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: Part/Draft constraint equivalents

Postby chrisb » Wed Mar 20, 2019 2:16 am

garya wrote:
Tue Mar 19, 2019 2:15 pm
I wanted to understand how to use Draft better.
Nothing to say against this argument.
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NormandC
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Re: Part/Draft constraint equivalents

Postby NormandC » Wed Mar 20, 2019 3:10 am

You have to think of Draft 2D geometry tools as like a drawing board. It's a little like drafting in AutoCAD (or LibreCAD), if you've used it. I admit that it's been ages since I've worked that way, I seldom use Draft geometry tools (I was around when Draft was the only way to create 2D geometry, Sketcher didn't exist yet!).

garya wrote:
Tue Mar 19, 2019 4:13 am
1. How to lay out construction lines based on angles rather than trig computations to position the endpoint of the rays
In the Draft Line Tasks when it's active, there's an input field to set an angle as well as a checkbox to lock the angle; and you have a Length field.

If a line is already drawn, you can use Draft Rotate to rotate it to the desired angle.

garya wrote:
Tue Mar 19, 2019 4:13 am
2. I can line up one of the points on the lines with the construction, but when I go to move another point the whole polygon moves. Is there a way to keep the lines with "flexible length" so the endpoints can be positioned and they grow and shrink as needed?
What tool are you using, Move? Use Draft Edit instead. First select the "Tooth" DWire, then press Image Draft Edit. It works for me, I can move points independently from each other.