Was not happy with abs plastic tips. After a little testing on some scrap plastic, found it would fatigue cracking quickly. Due to big variation in thickness, it was pretty flimsy where rivets installed so anticipated it would break in short order. What to do??
Bought some 1" wide kevlar tape from fiber glastonbury inc. 30 ft roll, $27. Also found it at Jamestown boat supply for $16.
Attached to inside of tips along rivet line. Adhered with 3M77 to make it adhear to plastic. Rough up plastic with 80 grit to give it a tooth to hang on to. Then a plied 3 coats of cynoacrilate (super) glue. Bough in a 4 oz bottle for $16. Apply to kevlar by rubbing it in with a nitrile rubber glove on hand. Let it really soak in to kevlar. Wait 5 mi utes between coats. Then drill out for rivets.
After fully cured, tested on scrap plastic. No fatigue cracking! Really strengthens the tips, adds about .011 thickness to plastic.
Much improved and am satisfied now the tips won't cracking out. The 3M77 and super glue have excellent adhesion to plastic. Be sure and rougher up with 80 grit before applying kevlar tape.
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