I was recommended ML Hand's Rules of Thumb for Structural Design a long time ago by my old manager. I had the 1993 photocopied version. I have since found the Version 3-6 on the internet, so it looks like this document has been updated over the course of decade or more. Such as here...
Totally understood - my contrast with hi-loks is because they make design considerations simple and a higher capability joint. I need to use flush head, I need to use nut plates, so I’m left with possibly bad preload or threads in bearing. The lesser of the two evils is threads in bearing, but...
Good point - mostly flush head. Washer is a good solution if that wasn’t the case.
Still, it would be fantastic if most nutplates had more thread relief. It is very simple to consider hi-loks when, by design, they don’t bottom out and don’t have threads in bearing, where it appears nut plates...
SWComposites - good question, but I don’t really know all the circumstances under which those worked before. Maybe most of those nut plates that posed no problem were installed to a non-load bearing carrier outside the loaded panels, or maybe the analyst checked a reduced bearing area in...
WKTaylor - agree, intent is to avoid threads in bearing and bottoming the threads in the nut plate barrel. However, consider the following example - it just doesn’t seem like the standard nut plate has sufficient thread relief.
Suppose you have a 1/4-28 bolt with max two incomplete threads...
Why are nut plate counterbores they depth they are? Or if OEMs find them acceptable, how do they balance nut interference and threads in bearing?
It seems obvious that nut plate counterbores are .0625 because that matches a bolt grip, but it seems like looking at the specs, it is too short...
I’m loving TeamCenter Visualization Mockup for opening big models. However, I get thousands of rows in my Project Workspace. It shows one line for each fastener where in NX there is a ”Pack” command that will group like-items, such as bolt x20, washer x40, nut x20. Does Teamcenter Vis have a...
3DDave, TheTick, powerhound - thanks for the replies.
I looked at this case in more detail, because it did seem like surface finish wasn't met... even though block tolerances call out Ra and not Rmax.
Working in theory and general terms is nice, but this specific one had a .003" step.
I drew...
Thanks for all the replies.
@3DDave and others - I have little/no control over firing a vendor. I could make a stink on some parts and ask for "return-to-vendor" that would maybe start to hurt a vendor's score card, but it's hard when Quality is saying "what's the violation?"
@ many - I could...
I'm a designer - there is a recurring theme with some parts we've seen recently, where there is a sharp step right where we'd least want one. We battle with other departments - they say it meets the print, we say it doesn't.
For example, we might design a bracket with a fillet/blend...