Removing silicone repair

[Nicolas Langlois]

Hi everyone

The previous owner of my camper did some repair on the roof with silicone. Obviously, these repairs don't seem to be very long lasting since they already leak ( at least one of them).

The silicone is really hard and pretty much impossible to cut with a knife.

I am wondering what would be my best shot to repair it.

I was thinking of using a grinder with a flap disc. It will probably ruin the disc pretty fast and need a few of them. What do you guys think?

[Raspy]

It's kinda hard to tell, but it looks like there is a hole that got plugged up with the silicone and then it got spread around a bit. Is that right? If it was a bolt hole, you might drill it out to the next size and get rid of the silicone plug. Then sand the surrounding area to get the last of it.

Flap disk seems like a reasonable choice, or a random orbital for more cautious work and final feathering. Just don't make a giant hole. If you can get all of the silicone out of there, you can fill and feather it with Marine Tex, or equivalent, white epoxy. Or, of course, fiberglass resin and cloth, and paint.

BTW, I recently got a Ryobi random orbital battery powered sander from Home Depot and it is one of the best tools I have. Exceptionally useful. Cheap too.

[Defenestrator]

Mineral spirits should soften up the silicone enough to make removing it easier, and won't damage the gelcoat or fiberglass.

[Carl V]

If you can find this, it works reasonably good:

[John in Michigan]

On several threads, use of plastic razor blades is mentioned. They are designed to fit into tools that use single (edit: or double) blade razors. Can be bought at hardware stores.

[HawkBoler72]

I sanded them off using a grinder with a flap disc, then fiber glassed the part flat.

[stevebaz]

Might try an oscillating tool with a flat scraper blade.

https://www.harborfreight.com/oscill...ool-62279.html

[wbullivant]

I would try the Multi-tool first using a serrated knife edge blade. This tool cuts through soft material amazingly well. I personally found it was the best way to remove excess polyurethane foam without damaging adjacent material. It will leave a thin film that you can probably remove with solvents that others have suggested.

https://www.harborfreight.com/4-in-h...ade-61813.html

[Kai in Seattle]

A hole in your roof should be repaired with fiberglass, not caulk!


As you've amply demonstrated, never use silicone on these fiberglass trailers. It WILL leak. It IS a pain to remove.


Use butyl rubber where you can't use fiberglass; either butyl tape or butyl cault (getting harder to find around here). The tape comes in black, gray, and white.


BEST
Lots of work, but well worth it when well and truly finished.


Kai

[Nicolas Langlois]

thank you guys for all the pieces of advice, I will start with silicone softener then go for the grinder with flap disc since I already have one. If it doesn't work well I will go get one of these tools.

Will definitely let you guys know about how it goes.

Cheers

[Nicolas Langlois]

Hi guys

So here it is,

I first tried with an oscillating tool with a flat scraper blade. It worked like a charm to get the silicone off. however, my discover underneath is not what I expected.

For the four small patches on the door side.

There are some screws that look like they are from the factory of there since a long long time (see pictures below). I am wondering if I can fiberglass over them?

For the big patch in the middle,
The roof is cracked. (see pictures). I used a flap disc to clear the area (this tool is fantastic). I am wondering how deep or how large should I clear the area? How big of a trouble am I facing?

[HawkBoler72]

Are the nails still needed? I would sand the area deeper and wider, then FG them. For the other place, I would extend the area about 2" each side and deep enough such that applying two layers of FG where will be still leveled with their neighbors. They will be not a problem then.