Best practice for creating many rivet holes etc?


A turboCAD user said when creating rivets dont just draw hole cutting solids (I use cylinders), transform copy them then boolean them out of solids, use a Block Instance. The prog has then only to remember the one and writes faster looking at instances as opposed to each as a separate unique item.,

Just what does that involve when making cutting solids ?

I even use crosses but notice the redraw and speed slows down when I get to place loads of rivets or crosses, certainly the rivet holes all over an item. With rivets being two or three different sizes, then there are the countersunk holes, what is best practice ?


(Pascal Golay) #2

Hi Steve -Do you need to model each and every rivet and hole or do you need to specify location and radius, or do you need to make it look like there are rivets in a picture?


(Brian James) #3

Hi Steve,

It would be good to see a model and picture of the type of thing you’re going for. I believe I know what you’re running into though when many objects slow down the display rotation. You can reduce the render mesh for these objects as one approach to gain display speed and you can use Blocks to reduce file size but the display won’t be faster by much. Check out the technique I show below for a speedy display with lots of separate objects. The video is part of a series but your question relates to this segment.


Its a jigsaw puzzle of old aircraft parts that I only get to find out how they fit together when their rivet locations match. (Aluminium shapes, L section stiffeners and longerons etc). The part must then be ‘makeable’ and it must be obvious to the maker where the rivets go, the holes to drill, and the diameters of the holes. I dimension up the 3D item indicating rivet hole diameters, bolt hole diameters etc.which gets turned into 2D plans.

I dont take that part into my ‘assembly area’ along with its dims, just the 3D part and its crosses or holes and marry it up with other items by matching these crosses or holes. I guess it looks nice and realistic with holes and I fall for that ! Crosses would have to be projected through to both faces of what is often sheet aluminium to allow perspective view assembly. Booleaning holes does that projection in one go, and its very rewarding to the soul to see the part as it would be in reality !


(Pascal Golay) #5

Hmm… I think, if I understand you, your soul is going to have to wait for its reward… trimming out each hole for an entire plane’s worth of rivets is asking for trouble. I think I’d place a cross at each rivet hole center and doing this with blocks makes some sense. BUT, I may not be accurately picturing the scenario.



Does block instances, of which I have never dabbled at all, allow the use of holes cut in sheet (solid) items representing aluminium, or is it only for 2D items like crosses ?

I didnt realise that CAD got bogged down with repeated details. Seeing panels with their holes makes for pleasing and understandable detail/viewing. One or the other IS needed though to help relate the item to photos, its sort of detective work as well not knowing where the part fits then seeing it in a photos and that eureka moment.


(Pascal Golay) #7

Well, blocks are perfectly valid as 3d objects but they cannot be used to Boolean, and even if they could, it would lead to exactly the same problem as with any other object.