fasteners

Here's the place to start. Introduce yourself and your ride.

Moderator: david58

Post Reply
Ol'fogasaurus
Posts: 13570
Joined: Tue Nov 14, 2006 1:17 am
Location: Just north of Seattle

fasteners

Post by Ol'fogasaurus » Wed Apr 11, 2018 11:46 am

The question on fasteners came up and I posted this in the wrong place. Some thoughts based on my experiences with them.

https://www.astm.org/Standards/fastener-standards.html

And then there are Fed Spec'd fasteners (and other processes within some of the specs shown here) such as AN, NAS, AND, MIL and so on. Add to that you have the metric specs and (probably) specs from each country around the world plus fasteners made by companies that are also speced to their needs. I am not sure I have covered all of the problems either. It is all very confusing and what you get from off-shore (or even withing the states) can be very questionable.

Fed specs. have a lot of close tolerance fitting and testing requirements found within the specs applicable each batch of fasteners produced. Not sure about a lot of the other manufactures standards. The ones I worked on their design or worked with were tightly controlled (its hard to replace a bolt at 34K feet in the air ). There were grounded airplanes at times when the test (et al) data did not arrive with the fasteners or within the time allotment.
https://www.astm.org/Standards/fastener-standards.html

And then there are Fed Spec'd fasteners (and other processes within some of the specs shown here) such as AN, NAS, AND, MIL and so on. Add to that you have the metric specs and (probably) specs from each country around the world plus fasteners made by companies that are also speced to their needs. I am not sure I have covered all of the problems either. It is all very confusing and what you get from off-shore (or even withing the states) can be very questionable.

Fed specs. have a lot of close tolerance fitting and testing requirements found within the specs applicable each batch of fasteners produced. Not sure about a lot of the other manufactures standards. The ones I worked on their design or worked with were tightly controlled (its hard to replace a bolt at 34K feet in the air ). There were grounded airplanes at times when the test (et al) data did not arrive with the fasteners or within the time allotment.

Lee

Ol'fogasaurus
Posts: 13570
Joined: Tue Nov 14, 2006 1:17 am
Location: Just north of Seattle

Re: fasteners

Post by Ol'fogasaurus » Thu Apr 19, 2018 11:50 am

http://homepages.cae.wisc.edu/~me231/on ... andout.pdf

This is one of those things that you will probably forget about but just may come in handy at some time in your future. It talks about the detail basics of fasteners; "fasteners" this time meaning certain basic types of bolts and of screws. How to read the blueprints when pertaining to fasteners, and details on several styles of fasteners.

It does miss some of the "whys" but basically it is pretty good. One of the "whys" might be why are the flutes on the underside of the head machined away so not to be flat (it allows you to turn the bolt by the head of the bolt and not have the flutes dig in. The same for the nut.).

Lee

Post Reply