Hi,
Most often captive or welded-on nuts are used in difficult to access areas.
So, it might be difficult or impossible to just replace with a regular nut and
bolt. And, fixed nuts are often used in places where vibration loosening is a
problem.
So, if it is accessible and you do decide to use a regular nut and botl, be
sure to use extra anti-loosening aids, such as Locktite, Nylock nuts and/or
locking washers. For example, the welded nut loosened from the sheet metal at
one of the hood hinge bolts on my car. I replaced with a strong nut and bolt
until I had the car apart and could get to it with a welding torch. However,
even
with a locking washer, I frequently found it loose or missing entirely!
I'd normally just tack weld in a new nut. However, if you don't want to
damage paint or simply don't have welding equipment available, there are
replacement snap in type caged nuts available. Or, if the sheet metal is
damaged to the
point where the snap in type won't hold, there are caged nuts that can be
riveted in place. See
http://www.pegasusautoracing.com/ProductSelection.asp?Product=MS21059 for an
example.
For small fasteners under light stress, there are rivet nuts available. I've
been using these for brake line and fuel line support clamp attachments to
frame rails. They are especially useful in this sort of blind application,
where
you can't get to the back side. But, rivet nuts are limited to light stress,
aren't cheap to use, and the largest size is around 1/4". I prefer the steel
type, the aluminum ones are easy to strip the threads out of during
installation. Another option is those with anti-rotation keys, but they are
more expensive
and take longer to install. For additional info see
http://www.pegasusautoracing.com/group.asp?GroupID=HARDNUTSERT
Hope this helps.
Alan Myers
San Jose, Calif.
AMfoto1@aol.com
http://hometown.aol.com/amfoto1/amfoto1.htm
My question for those who have "been there done that", does anyone see a
problem with replacing these sheet metal fasteners with a regular nut and
bolt
set up?
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