Is there a way to put a "Stop" on a Screw Mate?? (Planer Mate?)

christopher_owens

For instance when a bolt head seats on a washe, or two parts "Planer Mate" when screwed together. I used a Screw Mate and one part will continue to pass through the other when it should "bottom" and stop. Hmmm... I guess I could have a Planer Mate I suppress...

lougallo

@christopher_owens You are looking for a limit mate.. We have not released one yet.

christopher_owens

OK, tried the Fastened Mate after suppressing the Cylindrical and Screw Mates. BUT, I saw there is a Reset under the Cylindrical Mate. So I deleted the Fastened Mate. Although it seems to take a certain order of Reset, suppress the Screw Mate, move the part with the Triad, and unsuppress the Screw Mate so it works again (which lets the parts pass through each other again) and then use Reset again to get to the starting point. In the assembly the yellow part would "bottom" on the blue part.

lougallo

@christopher_owens You are looking for a limit mate.. We have not released one yet.

christopher_owens

@lougallo Thanks! At least I know how get the parts back to the "start" position!

philip_thomas

@christopher_owens - the 'reset mate' capability is very powerful and its value becomes even more apparent when you start to build more complex mechanisms (resetting before adding mate relations makes life a whole lot easier). Lou is also being very restrained about limit mates. Its obviously something that's logically needed and like most capabilities that live in that category, it's a safe bet that we will soon be (or are ) working on it. Remember, unlike installed CAD that has a 1 year major release cycle, Onshape releases approximately every 3 weeks - bringing new productivity tools to its users far earlier than with installed CAD. 

brucebartlett

Sounds like it has already been coded just waiting for the QA check off.

christopher_owens

@philip_thomas  & @brucebartlett   & @lougallo  Thanks for the responses! Figured I would ask for this simple example. I was wondering, since most threads seem to be made from the Helix feature, could the Screw mate be associated with that?? The Helix has "limits" and a ratio already. Modify the Helix and the Screw mate corresponds.

viru

@christopher_owens , User can use screw relationship constrain for screw as shown below video.

peter_hall

I feel the limit mate needs to be to a face of another body generally rather than a specific distance, to use with stop blocks which would often be designed into a working assembly.

andrew_troup

@peter_hall:
You make a very interesting point. There will always be the need for a distance-specified limit mate, it seems to me... 

Not least, because range of motion is generally established early in a mechanism design, whereas stop blocks tend to be added once the main elements have been fleshed out.

But I can see real advantages in rethinking the whole work flow in the light of the point you raise.

One promising possibility, I reckon, would be the ability (as an alternative to distance) to specify limits in terms of (say) mate connectors, which would become a visible but conceptual (and hence irreducibly simple) 'stop block'. Then when the real stop blocks get added, they could simply be mated to the pre-existing connectors.

peter_hall

@andrew_troup
I am completely new to design, as you can probably can tell! Started when I joined Onshape on July 16th...although I have an engineering past.
I like the sound of specifying limits in terms of mate connectors especialy as you can create your own mate connector positions on onshape. As a matter of interest can you create a mate connector position in space or does it have to be on existing defined geometry? I hope that makes sense.

andrew_troup

You certainly can create it in space, that's an astute and pertinent question. However it is not currently straightforward to relate it purely to construction planes, and that's an enhancement which I think would be quite valuable. 

At present, it can either be created on a model face or feature, then translated out into space, or created midway between faces/features, (and then optionally translated and/or reoriented to somewhere else in space) 

I would personally like to also see the addition of construction axes, and coordinate systems, with the same user interface and toolset.

3dcad

Very nice idea to use mate connectors as limits in assembly. It would be just enough for visual needs and familiar parameters to edit.

peter_hall

@brucebartlett
I assume from your above comment that some form of constraints for screws , slide etc are imminent. I do hope so as the inability to do so and the resulting part1 moving through part2 etc is extremely limiting for assembly design.