Shorter screws for fuel tanks

digidocs · #1 03-30-2013, 09:44 PM

(old message removed)

David Z · #2 03-31-2013, 05:50 AM

I quite often use a shorter bolt and/or a thin washer compared to what's called out. As long as there is thread out the end of the nut it is okay.

The only issue I see with replacing all of them is having to pay for that many more screws. If it were me, I'd just replace the wrecked ones with the shorter screws.

Bruce · #3 03-31-2013, 06:10 AM

David,

The AN's are structual screws.

Make sure they are the same AN #.

rvbuilder2002 · #4 03-31-2013, 02:29 PM

Quote:

Originally Posted by David Z

I quite often use a shorter bolt and/or a thin washer compared to what's called out. As long as there is thread out the end of the nut it is okay.

Not always.
Most fasteners in a RV are loaded in shear. For a structural fastener to properly carry the shear load, the parts should only be baring on the un-threaded shank of the bolt. In many instances, if a shorter bolt is used with a thin washer, there will be sufficient threads (minimum of one) showing outside the nut, but a thin part of the stack up may be baring on the bolt threads. Not a good practice.

Quote:

Originally Posted by Bruce

David,

The AN's are structual screws.

Make sure they are the same AN #.

Structural screws (generally) have a portion of the shank that is un-threaded (like shown in the photo) for the reason mentioned above.