I made fully constrained sketches today... why?

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Absinthe
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Re: I made fully constrained sketches today... why?

Post by Absinthe »

Okay, so I made a fully Constrained blade, using the spreadsheet, and except for geometric things everything else was a field from the spreadsheet.

I was able to see changing some of the values and observe legitimate transformations. This was cool.
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Absinthe
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Re: I made fully constrained sketches today... why?

Post by Absinthe »

Wasn't sure I could do this:
Here it is, in case anyone can make some recommendations on doing it better.
constrained_slipjoint.FCStd
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Shalmeneser
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Re: I made fully constrained sketches today... why?

Post by Shalmeneser »

Usign a SpreadSheet here is useless.
WYSIWYG is better : you see in the sketch what any dimension is used for.

SpreadSheet can be useful when the same dimension is used in many locations.
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Capture d’écran 2022-08-04 152648.jpg
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adrianinsaval
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Re: I made fully constrained sketches today... why?

Post by adrianinsaval »

Absinthe wrote: Thu Aug 04, 2022 12:52 am Can I do that without a spreadsheet?
Yes, for simple stuff like this it's a matter of preference, do you prefer to edit a nice clean list of values in a spreadsheet or do you prefer to do it in sketcher where you can see what some of those dimensions are?
When you take the spreadsheet approach I recommend using Macro EasyAlias, very handy for setting up your variables.
When taking the sketcher approach I recommend assigning meaningful names to the constraints that will be referenced in other constraints, this will make your life easier when writing or editing the expressions and will protect you from constraint index changes if you happen to delete a constraint later on.
Shalmeneser wrote: Thu Aug 04, 2022 1:29 pm WYSIWYG is better : you see in the sketch what any dimension is used for.
This is subjective, sometimes it's easier to edit several values in a spreadsheet than to open constraints one at a time to edit them.
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Shalmeneser
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Re: I made fully constrained sketches today... why?

Post by Shalmeneser »

adrianinsaval wrote: Thu Aug 04, 2022 2:19 pm ... sometimes it's easier to edit several values in a spreadsheet than to open constraints one at a time to edit them.
True. Perhaps the only usefulness of SpreadSheet.
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adrianinsaval
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Re: I made fully constrained sketches today... why?

Post by adrianinsaval »

Absinthe wrote: Thu Aug 04, 2022 4:54 am Wasn't sure I could do this:
Here it is, in case anyone can make some recommendations on doing it better.

constrained_slipjoint.FCStd
Very nice and dare I say impressive for a beginner! Regarding the sketch itself, I noticed the arc on the edge side of the blade is not tangent to the straight section, is this on purpose? I would expect it to be tangent, in that case either the radius or the horz. distance constraint would have to be removed.
I also noticed these repeated constraints:
Captura de pantalla 2022-08-04 103021.png
Captura de pantalla 2022-08-04 103021.png (9.77 KiB) Viewed 614 times
Here it would have been better to either use a point on object constraint to make that point coincident to the straight edge of the blade or even better to make that a single line instead.
There's also several 10mm constraints, if those are always meant to be equal you may just use equality constraint among them and have only one dimensional constraint, but it's good to constraint them separately if the dimensions are independent from each other and I suspect that is the case here.
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Shalmeneser
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Re: I made fully constrained sketches today... why?

Post by Shalmeneser »

@adrianinsaval : +1
Absinthe
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Re: I made fully constrained sketches today... why?

Post by Absinthe »

adrianinsaval wrote: Thu Aug 04, 2022 2:48 pm
Very nice and dare I say impressive for a beginner! Regarding the sketch itself, I noticed the arc on the edge side of the blade is not tangent to the straight section, is this on purpose?

I would expect it to be tangent, in that case either the radius or the horz. distance constraint would have to be removed.

I was not aware I could do that, or how it would behave. It seems much better that way, and I have been able to remove the pointHeight value as well. I don't think it affected the radii or horiz distances, just no longer requires the pointHeight.


I also noticed these repeated constraints:
Here it would have been better to either use a point on object constraint to make that point coincident to the straight edge of the blade or even better to make that a single line instead.

I made the points across to be horizontal constraint and that solved the issue. Again, I was just mashing buttons until it said "Fully Constrained" :)

There's also several 10mm constraints, if those are always meant to be equal you may just use equality constraint among them and have only one dimensional constraint, but it's good to constraint them separately if the dimensions are independent from each other and I suspect that is the case here.

Those are incidentally equal at the present. However, I am not sure they have to be, so they are independent values.
Thanks!! Responses inline.
Absinthe
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Re: I made fully constrained sketches today... why?

Post by Absinthe »

For everyone that took the time to look and respond, thanks!

I took a run at the spring, and liner (handle). I couldn't figure out a good way to paramatize all/any of the constraints it took to get those two fully constrained. I was really only able to use a couple of the previous ones. It is an ugly mess. Has to be a much better way.

But, just in case anyone wants to see, here is the latest. Any ideas on better constraining this?
constrained_slipjoint.FCStd
Ugly constraints
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