Tolerances on rivet length

[sbakker5]

I have a question regarding rivet length, how much under or over the 1.5 x the diameter are you allowed? for example nose rib attachment angles require a MS20470-3 the -3 (3/16") looks like it is slightly to small by 0.01inch or 0.26mm and the-4 (1/4") will be 0.05inch or 1.33mm longer then required. Would I need the buy the longer MS20470-3-4 and cut the 0.05inch off the end of the rivet or would I by a MS20470-3-3 and just get away with the length being slightly short?

Regards Simon

[Chris In Milwaukee]

There is a -3.5 that I used for those. I don't remember where I got them, but they should be available. Barring that, I wouldn't hesitate to use a -4 in its place. As long. As it's driven straight, you should be good to go.

[mswain]

I'm with Chris, I used mostly 3.5. I found the -3 to be a bit too short for me, although I primed everything before assembly, and the paint adds some thickness. I would order you some of each and practice on some scrap, see what kind of dimensions you get on the shop head.

You need a minimum of 1.5 X Rivet Diameter for the formed head diameter and .5 to .65 X Rivet Diameter formed head height.

Personally, I prefer erring on the longer side....but it is easier to malform a rivet if it's too long. The half sizes worked great for me, especially when skinning the wings with the AN426 rivets.

[Bcone1381]

I like what Glenn Patterson and Mark Goldberg have to say about riveting in this thread.

The Mil Spec Rivet Tolerances as are found here

A simplified pictorial interpretation of Mil-R-46196(MI) is below

[Chris In Milwaukee]

I remember that thread. Great information. Probably one of the best descriptions on "why" something is done that I've ever read.

[sbakker5]

Thank you for the replies I have read the thread and it makes sense to me

Regards Simon