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3D Fasteners - LOD & usefulness?

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I have done some fasteners that I thought would be of some use in my work, but I modeled then and have found that the LOD (level of detail) required for differentiation from that of bolts and screws that are already in the library of tools has significantly increased memory usage and computational needs. Significant to the level that I don't think their use is feasible for anything more than a couple of instances in any one design layer or file.

Attached is a screw in concrete anchor of which there are more sizes that I should typically use for detailing installations of steel assemblies.


Any suggestions of changes that could make these workable?


To make these as plugins I think I would have to figure out a more reliable way of illustrating the threads. My efforts of extruding along a helical path have been hit and miss as to whether the result can be processed by solid addition to the shaft. And that was doing it without scripting. I say scripting because I believe that direction would be far more successful at controlling memory use and the clutter of unused profiles in a file's symbol folder. I suppose I could create a library file that the plugin could retrieve each symbol from when called upon for use, but that wouldn't solve excessive file size increases with each instance of various fasteners.

#4x0.375 concrete anchor Sim toTiten™.vwx

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First, beautiful work on the anchor.


Second, why? 😉


Many people want to simulate reality rather than generate something that is sufficient.  Your model appears to be close to perfection. But in actual use does that matter or can you simplify the object and get what you need?


On my monitor, at even 1:2 scale and 100% zoom the numbers on the top of the anchor disappear. The fine fillets don't really show. Unless you are documenting the anchor itself, in most instances that threads will not show as they will be completely embedded in another object.


For use in Viewports you could make this into symbols and give the different parts different levels of detail (Low, medium, high) via a script. But you will still be putting a lot of unnecessary detail into the drawing if your normal output is 1:4 or 1:48. 


If you were designing the anchor then I absolutely would say you need all of that detail.


If you are using the anchor, especially if you are using a lot of them in a drawing that will only be output at small scales, then you should simplify. Or even create multiple versions. A head only version to show where they go and a version with either threads or just a shaft if you need to do partial "exploded" views. And use polygons to simulate the circles.  In most uses you will not be able to tell the difference between a polygon with 36 sides (10° angles) and the circle at reasonable scales. No one will be able to tell the difference in this case if the top of the flange is a curve or a swept straight line. Or that there are the teeth on the bottom of the flange.  The actual part specification since this will be a purchased part can be a single line of text rather than a 100% accurate drawing of the purchased component.


And make sure you only have the geometry in the file once and that you use the objects as symbols.  Any maybe do different LOD in different classes so you can turn the high detail versions off while you are working and only turn them on when you need the final renders.


I worked on a project one time where the lead insisted that we include the wall hooks and hanging wires on the back of the picture frames in the model.  When he complained about it being slow we turned off the class that included those things and never turned it back on.  It offended his sense of perfection to to include those things but they never showed and were completely worthless in the model.


10 or 50 years from now computers will be fast enough to model reality. But for now, IMNSHO, the drawings we produce, and the models they come from are a communication tool. I know people say you can't over communicate, but you can. 


If you believe that you truly need 100% accuracy in all of your modeled components, then make sure you have the biggest fastest computer you can get and always run the most current version of VW or any other software. Both the hardware and software get faster each year.  But my guess is that you will still be disappointed for the foreseeable future with how slow reality is.





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Posted (edited)

Thanks Pat, the change in focus really helps.


I stripped down the Simpson like product which reduced the file to 20% of the previous version and then noticed that the model now more closely resembled Hilti's concrete screw anchor. So I copied and made the minor thread and text adjustments.

Definitely using symbols for repeated instances will be required if I cannot pull them off as plugin items.

<edit: also I'll be lucky if I am still doing this in 5 years let alone 50, so I will not be waiting around for technology improvements and operating system optimizations 🙃>

#4x0.375 concrete anchor Sim to Hilti & Simpson.vwx

Edited by LarryO
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I too have gotten caught up numerous times trying to get everything perfect. But then at some point I realized that as long as the key overall dimensions are correct (mostly distance and spacing to mate with other parts) that as long as it looks "close enough" then that is all that is needed.


There are times when you are doing marketing drawings where it needs to look really good, but those don't usually need to be 100% correct.


So balance the level of detail to the required use.


I'm glad it helped.  I was afraid I was coming off as a little bit preachy. 😉

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I was reminded that a sweep does almost the same task as using a helix path for an extrude as long as one doesn't need to taper it down to a different radius. 

Tools that I have not used in a while.


The sweep seems to have shaved off a few more KB.

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For those of us old enough to remember (and not too old to forget), it's useful to think about how we got things built in the days of hand drawing.  Architectural drawing sets are diagrams, not 1 to 1 models.


The fastener model is amazing nonetheless.

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