Locking/Pinning Objects

[brd]

Does anybody have any good rules of thumb for locking and pinning objects? We've had plenty of water cooler conversations around the office lately about what the right times are to lock dimensions and pin objects in place.

Personally, I'm not a big advocate of locking and pinning items because it adds parameters that the computer has to process. Then when you try to move/delete/copy/rotate/etc, it always gives you a message box that you have to read through. It's been my general observation that whenever someone clicks "OK" on a message box, they don't really know what Revit is changing for them, so my philosophy is NOT to lock or pin items to avoid these error messages later.

Others in the office disagree with me and insist on pinning column grids, walls, windows, etc. They also love locking dimensions on clear corridors and 4" door jambs. Their logic is "If you don't want it to move, lock/pin it." Anybody have a good suggestion for an office standard? What's been working for you guys?

[Dimitri Harvalias]

Over use of contraints (locking) can cause you grief later in the modeling process. The software needs to verify if a contrained item affects other itmes which cna very quickly result in a slow down but, more importantly, it can virtually make the model unworkable. If everything is related to everything else in a way that is rigidly controlled you'll find that pretty soon you can't do anything without affecting anything else.

Pinning is the preferred alternative for things that you don't want users to move inadvertantly. In my experience pinning does not create significant overhead in a model it just acts as a simple barrier to warn users that you better be sure you want to move this!

[Scott D Davis]

In my opinion, things should be locked to control design intent. If a door is supposed to always stay 18" clear from the strike/pull-side of the door to a wall for ADA, dimension the 1'-6" and lock it. If the wall moves, the door will keep the correct spacing. Pinning grids is a good idea, especially after they are set and the structural eng is working on the project. Don't wnat those shifting on you!

You are right though, that too many constraints can slow a model down as Revit re-calcs.

[brendan.mac]

In my experience, locking (or pinning) is a handy tool. In the initial stages of modelling, I don't use it. But moving further into documentation I will lock down grids and alignments. For the simple fact you don't want these suckers moving around the page inadvertently.
I will lock structural elements, such as columns to grids, so that if you move the grid(intentionally) the element will move with it.

The trick is to be aware what is locked (or pinned) and why.

In families, particularly curtain wall panels, I will lock down the 'front/back' reference plane so there are no funny offsets when imported into the project but that is one of the only times I will use it initially.

The use of locking (or pinning) normally comes down to an office standard of practice. Nothing worse than having someone on your documentation team who moves something without realising or thinking through the consequences.

[irwin]

Here's another thread that discusses this subject: http://forums.augi.com/showthread.php?t=10841. Note that what used to be called "lock objects" is now called "pin objects".

In that thread I mention when to use pin versus locking dimensions:
- If you want an object to stay where it is, use the push pin.
- If you want an object to move whenever some other object moves, lock a dimension or alignment.

That rule says which to use, but doesn't say whether to use either at all. Pinning objects is pretty safe -- it rarely leads to confusion and doesn't cost much in terms of performance, so go ahead and pin as much as you like. But, in my experience locking dimensions and alignments can often lead to confusion and slow performance. New users more often err on the side of putting too many locks, rather than too few. I recommend starting out by not locking many dimensions and only add more as necessary.