OK, I know what you are describing. The "ribbed" riv-nuts are not as sensitive to the hole size and "bite" into the fiberglass. The jack-nuts are not as weak as you might expect and instead of spinning when they "freeze" to the bolt, they break apart making removal easier than the riv-nuts. Every fastener is specifically designed for it's purpose, some work better in certain places than others. Jack nuts can be very useful for replacing where a riv-nut has messed up the hole in the fiberglass and is less sensitive to hole size. In fact in some instances where the hole was very enlarged I just use washers over the jack nut. This way I can keep the fastener in the same location and I don't have to do any fiberglass repair! I don't think you could do that with a ribbed riv-nut. David Teitelbaum --- In dmcnews@xxxxxxxxxxxxxxx, <rob@...> wrote: > > Hi Dave, > > > > Actually Dave what I'm calling a "ribbed aluminum Riv-nut" is exactly that. > It has a solid body but ribbed sides that provide more grip. These are > stronger than either "jack-nuts" or "well-nuts" which "Mr. G" correctly > identifies as such. Jack-nuts have four open ribs quite like, as you said, > an expansion nut but are therefore WEAKER than Riv-nuts. Well-nuts are > rubber except for the threads and are the weakest of all. Whoever told you > that Riv-nuts are not intended for fiberglass must not have been talking to > t ------------------------------------ To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: dmcnews-digest@xxxxxxxxxxxxxxx dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/