Disable Validity Check

I am using Sketchup Make 2017. I have created a component to represent a 10x24 round head Phillips machine screw. I created it at 10x scale and shrank it down. It looks great in my model. However, it gets changed when a validity check is done and it no longer looks good. I can switch off the automatic check for validity in the preferences menu and the fix is not done when I save the model.

My questions are 1) is this going to be a problem going forward with this model? and 2) is there a better approach to creating my machine screw?

If you leave the validity check disabled, the component wonlt get checked but then neither will the rest of the models you make. That may or may not be an issue. I generally leave it disabled for my modeling but I’m pretty AR about making sure my models are clean and properly constructed.

Very likely, though, your screw component could be drawn differently so that it doesn’t have any issues that the Validity Check would trap. Exactly what needs to be done differently is impossible to say without seeing the component you’ve got. How are you using the screw in other models? How does it get shown?

Here is a simple sketch with subject screw.Leg Sleeve Bearing and Connector.skp (149.4 KB)

I’m just getting started on an anesthesia machine class. When I finish teaching I’ll take a look.

I would say yes, a failed validity-check will need to be reconciled at some point (by someone - maybe not you if the un-fixed model is shared and someone else encounters the check failure). I often model objects with fine small-scale detail (e.g., screw threads that intersect a chamfer). I leave the validity-check enabled for Save operations. When I occasionally encounter a failure I cope with it right then. If the “damage” caused by the failed check is not obvious I use the Solid Inspector2 extension to help locate any new holes etc. Then I repair the geometry as needed and re-save until it’s clean.

As to modeling approach, I use a scale factor of 100X (rather than 10X) with a throw-away instance of the component being modeled. [After modeling is complete, the scaled instance can simply be deleted - no need to shrink anything and possibly make a mistake.] Some people use 1000X, but for me such a large scale causes camera close-in clipping to happen annoyingly easily, so I don’t scale up that far.

Edited to add a Pan-head machine screw I modeled in some detail for my project.
Screw Pan Head Phillips 6x32 5_8th.skp (338.9 KB)

I opened your model without difficulty in SU 2018 and Fixed it.

When I can view it, I see that the screwhead has a number of tiny gaps. Looks as if scaling up by 10x wasn’t enough.

And you have more circle segments than I would think necessary for such a small component, unless you will be viewing it VERY close up as part of a larger model. Try modelling it again at either 100x or 1000x, using only 12 or even 8 segment circles.

If you want the screwhead to be even more realistic, use a deeper recess, and taper it slightly so it is smaller at the bottom than the top. To achieve that, just Scale the bottom cross-shaped face about its centre by something like 0.9 scale factor. Philips screws were designed with a taper in the cross-head opening, so the screwdriver would ‘cam out’ if twisted too hard, rather than destroy the head.

Thanks, I was thinking of redoing it at 100x scale. The machine screw itself is not that important in my model. I do this type of thing to exercise my brain and learn how to do things with Sketchup. For me it is only a tool that i use for designing workshop projects, I find it invaluable for these projects, but I don’t have / take the time to delve deeply into it.

That sounds very sensible - just enough to get the job done.

I opened it in 2018, exploded the bolt, made it a component and saved it with no issues. Why that fixed it , I have no clue.2017Leg Sleeve Bearing and Connector.skp (233.3 KB)

You can apply the magic stuff to them and be back in a minute?


You must have been holding your tongue right that time.

You should correct the face orientation. The blue ones all need to be reversed.

FWIW, the thing TDahl mentioned about making a copy of a component and scaling it up before doing anything that might create geometry problems is demonstrated in a GIF by Box here:

The Dave Method

Those anesthesia students generally take more than a few minutes. Especially when you have to work in compliance, tidal volumes, partial pressures, Bourdon gauges and Thorpe tubes. Oh, and don’t forget Mr. Boyle. remember him, the old dead guy with the law. :smiley:

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I’m glad you guys are having such a good time with this. I rebuilt the stupid connector bolt, scaling it up x100, used a Bezier tool to produce a smooth curve, and the follow-me tool to produce the extruded surface. Then I modified the Phillips slot to prevent the driver from caming-out and the intersect faces tool to fit the driver slot into the bolt head. Finally, I reduced the whole thing by a factor of 100. All of this took 2 hours away from my workshop. If I took a couple more days to thread the end of my bolt I’d have the as good looking round-head Phillips 10x24 machine screw you’d see anywhere. But, it was fun and educational.

By the way, I am buffaloed by the intersect faces tool and worried about faces being inside-out. Tomorrow I’ll be back in my shop.

Thanks for all the help, guys.

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