I am new on here and enjoy the wealth of information. I have had great experience detailing fiberglass finish back to new and figured I would share that it is possible to bring a finish back from the dead.I do car detailing and my cars have to look perfect new all the time.
Got a used Rv inside was like new and I think this unit sat unused for a few years in the sun.
Now I need to get the oxidation off this used unit we just bought. I tried regular Mcquires for cars clearcoat cleaner compound on a 3000 rpm polishing wheel. Not good enough.I ordered through Amazon McGuires RV 3 step oxidation compound, polish and wax. Fiberglass is a tougher finish then clearcoat and this Oxidation compound is designed to cut through and really remove all the garbage and oxidation built on the finish.
It restored my dull slightly off white finish back to bright white and very shiny. As well as made me beat dead tired, But its well worth the effort.
WARNING!........Their is nothing that will work without the right tools, time, strenth and energy involved in taking on this big a surface on 29 ft Rv with slide outs. You need a polishing wheel ( Not an orbital buffer they are not powerfull at all. I tried the dual action kind they are easier to controll but I like the speed of reg car polisher and prefer the 10 lb 7 inch 3000 rpm wheel using McGuires medium cut rasberry colored foam pad. Made just for taking oxidation safely out of the fiberglass.
I started on the full molded fiberglass cap front. IT had a dull SATIN LIKE white finish on it very minimal shine. After applying the compound with 3000 rpm wheel, polish then wax Its as shiny as a new Rv or a new bathroom tub at Lowes.
LET ME TELL YOU THE SHINE JUST AFTER USING THE COMPOUND IS AMAZING!
IT works as its advertised.
Then you follow up with the polish on a rag and wipe it off right away. Polish takes off any film left by compound and adds oils back to finish. They have a pure wax but it has no UV blockers in it so I went back to what I used and loved for years on trailer---Protect all wax.Lack of UV blockers is what oxidizes the unit.
Its a very hard job, Takes per side about 4 hrs. I have to stop because it will wear you out holding polisher tightly and letting wheel and compound do its job. Its a good workout. But the end results are well worth the time. My RV had medium oxidation. I AM sure with a BAD OXIDIZED chalky finish you will need to constantly clean the oxididation AND BUILT UP COMPOUND it removes off the pad. But years of not cleaning and waxing require the pain staking process that goes along with removing all the dead finish to get down to fresh.
Please note.......... My unit is 7 years old and though it was oxidized some, but a dull shine was still appearant under oxidation, I knew the gelcoat seemed good still. If your unit has been neglected for say 10 years or more it may be possible that the oxidation has gone beyond the Gelcoat finish which gives the fiberglass its shine. If so, Your really have nothing to shine back up.
3 part restorer will remove the oxidation then the polish and wax will add oils back to finish but without the high gloss shine if the gelcoat is gone. Also the dullness may return as the oils dry out over the following weeks of months depending on fiberglass gel coat in bad condition. I would try a small section on an older unit and see if you get that desired shine before spending your efforts to restore the entire unit. If that is the case their are other polymer finishes that coat over the dead finish once you clear off dead oxidation and create a new shiny type coating that they claim will hold a nice shine back to old finish. I am sure you can see them on the net. People seem to like these products as well. I would only consider going that route if you indeed do not have a chance of restoring the gelcoat.Its been well over a year now and the finish has maintained how I finished it and looks great still. So those who say the dullness comes back if you do nothing for years again sure it will but rehular washing and fast waxing with protect-all or any good way cleaner will maintian units condition.