Can't fully constrain sketch Nor find broken portion in order to pad

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triplus
Posts: 8465
Joined: Mon Dec 12, 2011 4:45 pm

Re: Can't fully constrain sketch Nor find broken portion in order to pad

Postby triplus » Wed Jul 27, 2016 11:23 am

Yes i personally consider bad practice using tangent constraints for such tasks as i do imagine unnecessary stress is added to the solver.
jjman6
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Joined: Tue Jul 26, 2016 8:16 am
Location: Washington State

Re: Can't fully constrain sketch Nor find broken portion in order to pad

Postby jjman6 » Tue Aug 09, 2016 4:23 pm

I realized after seeing your guy's examples that i was doing it backwards. Because i had already started w/ my base i was trying to actually create a ridge by padding to my original base plate (thats the reason i traced around the outer perimeter because i was trying to pad it not pocket). It would have been easier to start w/ a thicker base and pocket all the cavities out as has basically been shown here.
quick61 wrote:Another thing with complex sketches like this, after taking Jim's suggestion to only do half and mirror, when starting the Sketch, start out with one closed profile and fully constrain it before starting to add more lines/arcs, etc.. This will help remove a massive amount of confusion in your construction of the sketch.

For instance, I would start with the lower corner like so -

ConstrainInSteps1.png

Then add another closed profile and fully constrain -

ConstrainInSteps2.png

- and one by one add a closed profile, fully, constrain, then do the next one by one and build it up like so -

ConstrainInSteps3.png

Notice that I do not need near as much external geometry and only a few distance constraints. I'll take it you end result is desired to be looking something like this -

ConstrainInSteps4.png

The Sketch around the outside is completely unnecessary and will not work when you try to Pocket. Just lay out your pockets on half the shape and then add a Mirror feature as Jim suggests.

Mark
jjman6
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Joined: Tue Jul 26, 2016 8:16 am
Location: Washington State

Re: Can't fully constrain sketch Nor find broken portion in order to pad

Postby jjman6 » Tue Aug 09, 2016 5:01 pm

So i have 2 more questions as it relates to the same draft.

#1 I've determined i need to relocate a few holes in my design. but when i go back & change the original sketch which locates them. It doesn't update the location in the final version? But when i show visibility for that sketch it shows the updated location.

#2 I've also decided to change the overall thickness of my design but can't figure out the best way to shave off 2mm from the bottom. Again going back to the original sketch that was padded won't update the end thickness as above (plus i need to shave the 2mm off the bottom). Whats the best way to make this change affect my final drawing without starting over (which i've already had to do a few times).
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quick61
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Re: Can't fully constrain sketch Nor find broken portion in order to pad

Postby quick61 » Tue Aug 09, 2016 6:16 pm

jjman6 wrote:So i have 2 more questions as it relates to the same draft.

#1 I've determined i need to relocate a few holes in my design. but when i go back & change the original sketch which locates them. It doesn't update the location in the final version? But when i show visibility for that sketch it shows the updated location.

#2 I've also decided to change the overall thickness of my design but can't figure out the best way to shave off 2mm from the bottom. Again going back to the original sketch that was padded won't update the end thickness as above (plus i need to shave the 2mm off the bottom). Whats the best way to make this change affect my final drawing without starting over (which i've already had to do a few times).
This sounds like you have forked the model. If you could post the file of what you have, we should be able to explain what has happened where and how to fix it. Without it, it's only guessing.

Mark
This post made with 0.0% Micro$oft products - GOT LINUX?
jjman6
Posts: 5
Joined: Tue Jul 26, 2016 8:16 am
Location: Washington State

Re: Can't fully constrain sketch Nor find broken portion in order to pad

Postby jjman6 » Tue Aug 09, 2016 10:30 pm

Not gonna lie its a complete mess. Because i did have to remake several things. there are many objects that can be deleted as they are no longer being used or directly referenced. Not sure what the best way to clean up the file would be either :?

So my 2 final pieces (or close too at least are the 'currentBottom' & 'currentTop'

The holes i want to relocate & resize are 'Pocket019' & 'Pocket020'.

Which also leaves me with having to reshape 1 of the ridges as it will now land on a whole so i need to move the ridge so that the through hole is clear for a bolt w/ washer & nut (again i'll have to revisit original sketch that does all the pockets to create the ridge & change the shape).
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my Y carriage.fcstd
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