Saving weight: aluminum washers etc?

[Stewie]

Hi all-
I am curious if anyone has experience or can point me to a link regarding the use of aluminum washers (and possibly nuts, bolts? in non-structural areas) as a means of saving some weight. This topic has been discussed on VAF in terms of torque values when mixing AL and FE hardware, but I'm curious if anyone has used, say, AL washers when assembling the wing spar, etc. Regarding galvanic corrosion, forum discussions seem to indicate this is not a particular problem, and the washers could always be given a shot of primer if that was a concern. Is this worth looking into? My bag of steel washers is pretty heavy...
Eric

[MauiLvrs]

Better to save on nuts... and use MS21042
http://www.aircraftspruce.com/catalog/hapages/an363.php

[Stewie]

Thanks Dave. Had no idea there were so many kinds of nuts...

[sbal0906]

The planet has 7 billion people now. There's bound to be all sorts of nuts...

... sorry....


I'll get back to work now.

[Toobuilder]

I'll second the use of the MS21042 whenever possible. These are used on my "company" airplane almost exclusively and after years of working with them, it just seems wrong to use the standard locknuts supplied by Van. I swap them out whenever I can.

While substitution of washers my not get you much in savings, it is a great attitude to have during the build. You could certainly look at the "L" (thin) version of steel washers to get you a savings as well. In many cases, the thick version supplied by Van is way overkill for the application.

As an example of another extreme weight saving measure, my company airplane also specifies that thread protrusion through a locknut only has to be "flush" rather than the typical 2 threads showing. Not suggesting anyone do this on the RV, but it's an indication of a good mindset to have.