[SOLVED] Approach to make a simple solid

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JohnRob
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Joined: Wed May 20, 2020 4:56 am

[SOLVED] Approach to make a simple solid

Postby JohnRob » Thu May 21, 2020 1:08 am

Hi,
I want to create a simple solid. It is a PCB 1.5 mm thick x 90 x 40 with a chamfer at each corner 10 in from the corners.

I've already made one by inserting a cube, setting the dimensions I want and adding chamfers to each corner. Easy but I didn't learn much.

Now I'm trying to create it by using Sketcher. I'm assuming I can extrude or add thickness once I have the 2D the way I want.

So I have a rectangle of the proper dimensions that is fully constrained.

My initial approach is to draw a line at 45° then move it to where I need it to create the chamfer. Or I could draw a line with the end points on my basic shape line(s) and put them 10 mm from the corner.
I've not been able to do either with any success. The best I can do is draw a line using the mouse and X,Y coordinates.... which (pardon my pun) is sketchy.

Am I going down the wrong road or just missing something basic?
Last edited by JohnRob on Sat May 23, 2020 3:23 am, edited 1 time in total.
vocx
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Re: Approach to make a simple solid

Postby vocx » Thu May 21, 2020 3:26 am

JohnRob wrote:
Thu May 21, 2020 1:08 am
...
Am I going down the wrong road or just missing something basic?
Yes, it sounds like something basic. Watch more Tutorials, and check the Sketcher reference.

Just draw lines, and try to attach them to the previously placed lines, check that you are using constraints.

Also showing a screenshot of your model is good to give the forum an idea of your project.
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chrisb
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Re: Approach to make a simple solid

Postby chrisb » Thu May 21, 2020 4:40 am

An often underrated tool is the polyline. It can do more than a freehand zigzag with its several continuation modes: start with a straight line, then press the M key and see that the lines are connected orthogonally, press the M key again ... and again ... Try it!
kisolre
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Re: Approach to make a simple solid

Postby kisolre » Thu May 21, 2020 5:30 am

JohnRob wrote:
Thu May 21, 2020 1:08 am
The best I can do is draw a line using the mouse and X,Y coordinates....
JohnRob wrote:
Thu May 21, 2020 1:08 am
that is fully constrained.
JohnRob wrote:
Thu May 21, 2020 1:08 am
something basic?
Draw the lines and constraint them properly?

Draw edges over the edges you want chamfered. Make sure you cross both edges. Use Sketcher_Trimming to remove unneeded parts of the edges. Reconstraint the sketch.
Bance
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Re: Approach to make a simple solid

Postby Bance » Thu May 21, 2020 8:08 am

Constraints can be applied to points as well as lines ;)
drmacro
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Re: Approach to make a simple solid

Postby drmacro » Thu May 21, 2020 12:21 pm

JohnRob wrote:
Thu May 21, 2020 1:08 am
...

Am I going down the wrong road or just missing something basic?
I made a short video creating the described board.
I did not do a voice over, but, it illustrates my normal practice of analyzing and figuring out what makes life easier.

In short, minimize dimensional constraints, thus I sketch one quadrant and do multi-transform with two mirror features.

Enjoy :) and please ask questions...


https://youtu.be/oc7cmhwpHEY
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JohnRob
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Re: Approach to make a simple solid

Postby JohnRob » Thu May 21, 2020 9:30 pm

Thank you so much.... your video was perfect. :D

I do have a question. I originally started with sketcher thinking I could convert it into a solid. You started with a solid and I can see how you progressed.

My question is. Would starting in sketcher be a viable approach? Or is it viable but more difficult?

Thanks

John
chrisb
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Re: Approach to make a simple solid

Postby chrisb » Thu May 21, 2020 10:18 pm

drmacro starts with a sketch as well. If you mean that he explicitely creates a body first, then there is no difference to your workflow, if you create the sketch from PartDesign workbench. The body is then created automatically.
drmacro
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Re: Approach to make a simple solid

Postby drmacro » Fri May 22, 2020 1:53 pm

JohnRob wrote:
Thu May 21, 2020 9:30 pm
Thank you so much.... your video was perfect. :D

I do have a question. I originally started with sketcher thinking I could convert it into a solid. You started with a solid and I can see how you progressed.

My question is. Would starting in sketcher be a viable approach? Or is it viable but more difficult?

Thanks

John
Did chrisb answer your question? ;)
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JohnRob
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Re: Approach to make a simple solid

Postby JohnRob » Fri May 22, 2020 4:34 pm

I've watched the tutorial many times (at 1/4 speed) and find there are a few actions I cannot replicate.

In the video by @vocx I can't duplicate the what appear to be automatic constraints to the drafting lines.

At :58 seconds, the video shows a draft polyline drawn from the top right point, by hand(mouse) to a point that will be the corner. What I cannot replicate is as soon as the corner point is clicked, the horizontal draft line becomes automatically constrained as horizontal. AND the start of the draft line appears to be constrained to the point it started at.

Then as the polyline is continued vertically downward as soon as the end point is clicked a what looks like a 90 degree constraint appears and the corner.

I've looked through all the keyboard shortcuts I could find with no luck.

I am using V 0.18 /4 Windows10/64. I noticed the constraint point icon is different could these features be in the unreleased 0.19?

BTW I'm learning by repeatedly creating this structure without referring to the video. I can get there but using more manual constraints. But I would like to understand the method used by vocx in the tutorial.




Thanks
John