Re-caulking radius roof

[bigb]

So I am re-fixing the roof after watching the video by James in another thread. I did buy the proper stuff per James. One thing James does is he pushes the nozzle deep into the channel resulting in a lot more sealant being applied than the factory application. My plan was to do this, but I also realized by doing it this way there will be a lot of sealant pushed deep into the channel and probably some will squeeze up under the edge into the other side. I am sure this will hold very well but my concern was, if this job ever has to be done again it will be impossible to remove the stuff deep down inside.
Winnebago originally installed the sealant just from the little ledge that sits down in the outside of the channel, to the fiberglass resulting in a very thin but easy to remove bead (see pic) which lasted 10 years in the sun.
My question is, if you have done this job before, what did you do, and if you haven't what would you do?

[imnprsd]

Because there are weep holes in the radius channel, I'm not a fan of putting a lot of glue behind the radius skin.

I am a fan of Eternabond, when it is applied right, but I don't like the black tape on my green roof radius.

Therefore, I wanted to find a better "clear" sealant method and so far I am very pleased with the results of following the regular Winnebago re-glue approach; and then I would wait 2-6 months and apply a top coat of "clear" Flex Seal out of the can for extra UV protection.

I'm betting the rubber, chemical composition of the Flex Seal Clear, when brushed on out of the can, will not degrade the "Clear" GeoCell "Proflex Clear" polyurethane or hybrid sealant that is so popular today.

Note: You do not want to mix silicon with polyurethane or with your hybrid sealants (as I am told) because the chemicals in the silicon will leach into and weaken the bond of the polyurethane.

For more information on how I did my roof radius seal, you can jump to the end of this thread:

https://www.winnieowners.com/forums/...-359122-2.html

[bigb]

Interesting....my rig is 10 years old and was stored outside in Phoenix yet the roof cove seal was original but in pretty bad shape. I've decided to re-paint the top edge as it was on my list anyway and now is the time since I'll have all the old sealant cleaned off, BTW it is pretty hard to get every last bit of the old stuff off, even using paint thinner and lacquer thinner, Scotchbrite pads and razors there is still a "shadow" of the old stuff, do you think it will cause an adhesion problem with the Geocel? I found that an old screwdriver with a 3/16" round shaft cut off at the end and a rag or Scotchbrite pad wrapped around it works perfectly for getting into the channel and getting things clean.

Since my roof paint is very, very dark brown (pearl) some black Eternabond might not look so bad but I'll hold off till I see how this holds up. My rig stays indoors all the time except for travel and not being full timers it probably won't see more than 60 days of sunlight a year.

[bigb]

I guess since I am painting it anyway I can go all out to remove every last trace of whatever was used by the factory, the edge of my random orbit sander fits down in there and I can sand the "shadow" off then clean up. This way in the future if I need to do it again I'll know the "shadow" will be Geocel.
The channel side won't be as easy but all the places my current seal lost adhesion were on the fiberglass side.

[Jim_HiTek]

I don't think you have much to worry about because I believe that whatever caulking you put there the heat cold cycles from year to year will make it disengage from that smooth painted aluminum channel so you will be able to pull it out in long strips, maybe 2 years later.

Like imnprsd above, I'm a fan of Eternabond for that job. But my roof is white so it blends right in. Ebond only comes in 3-4 colors as I recall, but I'd use it even if it didn't match my roof.

Anyway, here's a drawing or two:

First how it's normally done...



And here's one of Winnebago's attempts at a permanent fix...which failed, very similar to what 'James' is doing (I'm a different Jim/James):



Here's all I did using Ebond. No maintenance! And as long as I don't rack the RV too often, it'll stay in place.

[BobC]

Originally Posted by Jim_HiTek

Here's all I did using Ebond. No maintenance! And as long as I don't rack the RV too often, it'll stay in place.

Beautiful Eternabond job, Jim.

[Jim_HiTek]

Originally Posted by BobC

Beautiful Eternabond job, Jim.

Well, thanks, but actually I hired a couple guys down in San Felipe, Baja to do the work because I wanted to take pictures of the process and they were very inexpensive.

[bigb]

Is the Eternabond one continuous length?

[Jim_HiTek]

Originally Posted by bigb

Is the Eternabond one continuous length?

Yes, it's a 50' roll. I walked outside the RV one morning and there was a strip of caulking hanging down in my face. The original goo used by Winnie. So I had two rolls of 2" Eternabond 50' from Amazon shipped in (to a mail service in Mexico that has an office at the border in California) and then they brought it down for me to pick up at their mail office.

But it really doesn't been to be one continuous piece. I had a backup plan if the wind didn't let up and that was to cut it into 6 foot strips. Easier to install in windy conditions and works on the roof the same, I'd wager.

I told the workers to just carefully pull on that old original caulking that was still in place and they were able to get most of it, but where it wouldn't come out, I had them cover it with the Ebond. No biggie.

I'd seen several terrible DIY re-caulking jobs in RV parks over the prior year and I sure didn't want to smear caulking all over like they did, and Ebond was a far better choice IMO.

So far, after 4 years and no maintenance needed, I'm happy with it.

[bigb]

In light of the UV concerns I am considering applying the sealant first then the paint although it would slow me down a lot as I would have to wait for the sealant to fully cure. Maybe I'll paint first, apply sealant then come back later and tape it off and paint the sealant. I'm using base coat/clear coat with UV resistant activator in the clear.

[bigb]

Decided to do the paint and body work first. I found an easy wat to strip every last bit of the old sealant, a 3" Scotch Brite Roloc pad fitted onto a 2" Roloc rubber backing fits right in there and makes very quick work of it. Afterword's a thorough cleaning with lacquer thinner followed by grease and silicone remover to make sure none of it gets sanded into the finish. There was also a small hole near the antenna that someone had filled with silicone, I opened that up and removed all the loose and cracked fiberglass then repaired it by building up with cloth and resin followed by fiberglass Bondo followed by regular Bondo for the final smooth out. One side is sanded, primed and ready for color. It sure takes a while to mask off a class A motorhome, small as it is! I could never attempt this outdoors.

[Jim_HiTek]

Nice work.

[abqnm]

Jim, I'm not familiar with the ebond products mentioned. Is it a caulk that you put down inside the lip of the channel? Or is it the tape that is above? The discussion appears to be the use of tape but isn't the necessary seal at the radius piece that sets in the channel? I need to do this job and have watched the video but am confused as to the best method.

Welcome all advice and thanks in advance.

[Jim_HiTek]

Originally Posted by abqnm

Jim, I'm not familiar with the ebond products mentioned. Is it a caulk that you put down inside the lip of the channel? Or is it the tape that is above? The discussion appears to be the use of tape but isn't the necessary seal at the radius piece that sets in the channel? I need to do this job and have watched the video but am confused as to the best method.

Welcome all advice and thanks in advance.

What I had the workers do is to pull back the protector sheet 4 feet or so, and then carefully place the 2" wide Ebond TAPE (50 foot rolls) in the bottom of the channels rain gutter. So the channel next to where the Filon roof is placed. Then they would roll it up and rubber roller it onto the edge of the channel. Then force it into corners with plastic putty knives I loaned them. Then up and attached to the Filon, followed with the rubber roller treatment. So around 3/4" was attached where it could to the channel and 1 & 1/4" attached to the Filon roofing. Here's a picture:



Note that by the time the workers got to this end of the channel, they were getting sloppy and not getting the tape all the way to the bottom of the channel. No biggie so far as this end is the leeward end of the tape so not likely wind will lift it any. Plus it sticks like crazy.

The leading ends on either side (lft/rgt of the front of the RV) were smooshed into the bottom like I instructed so the tape has lots of channel to grip. I had them both clean the channels and brush them with a stiff brush before hand. And they pulled the old OEM installed caulking out (silicon type stuff, 1/8" bead, done by pros) as they went along. Where it still stuck and hung on, they just covered it with the Ebond. Only around 4' total where that happened in small lengths.

Keep in mind that under normal driving and camping conditions, Ebond tape does a great job preventing the Filon roof from detaching from the weak caulking bond that comes from the factory as it's gripping much more surface area of the roof...but...repeated racking of the RV getting to your favorite camping spot on a terrible road, can still cause the roof to pop out and away. That's why it's so important to prepare the surfaces when using the tape. And I would never install it in a rain or dust storm, when there is morning dew, when there's high moisture in the air, and when the wind is high.

[BobC]

Eternabond Tape:

https://www.amazon.com/s?k=eternabon...sl_22nwudvvw_b

[Farco]

I just did mine ala James method and do not agree with the above depiction.
As James says to “jam the tip of the gun into the channel” , it presses the fiberglass tightly against the channel behind. I doubt much sealant gets back there.
He merely wants to get the entire outward facing cavity filled. I had sealant filling up the outward side pretty quickly.

[NeilV]

Originally Posted by imnprsd

Because there are weep holes in the radius channel, I'm not a fan of putting a lot of glue behind the radius skin.

I am a fan of Eternabond, when it is applied right, but I don't like the black tape on my green roof radius.

Therefore, I wanted to find a better "clear" sealant method and so far I am very pleased with the results of following the regular Winnebago re-glue approach; and then I would wait 2-6 months and apply a top coat of "clear" Flex Seal out of the can for extra UV protection.

I'm betting the rubber, chemical composition of the Flex Seal Clear, when brushed on out of the can, will not degrade the "Clear" GeoCell "Proflex Clear" polyurethane or hybrid sealant that is so popular today.

Note: You do not want to mix silicon with polyurethane or with your hybrid sealants (as I am told) because the chemicals in the silicon will leach into and weaken the bond of the polyurethane.

For more information on how I did my roof radius seal, you can jump to the end of this thread:

https://www.winnieowners.com/forums/...-359122-2.html

FlexSeal can be great for many applications however I have not been impressed with its UV resistance over the years that I have used it. When exposed to direct sun here in Sunny Florida it tends to get brittle in very short time and can turn into something that is more like a hard plastic especially when applied in thin coats.

Test it to seal a seam on a dark colored tarp and see how flexible is stays after several weeks left out exposed to the elements 24 hours a day in a location that is not shaded from direct sun. In some applications I have seen it turn into alligator skin in less than a month especially the product in the spray can.

[bigb]

Originally Posted by Farco

I just did mine ala James method and do not agree with the above depiction.
As James says to “jam the tip of the gun into the channel” , it presses the fiberglass tightly against the channel behind. I doubt much sealant gets back there.
He merely wants to get the entire outward facing cavity filled. I had sealant filling up the outward side pretty quickly.

I tend to agree with you and when I drew the sketch I kind of exaggerated the amount behind the fiberglass, I don't think much will get back in there. It would also depend on how the cut the fiberglass, mine does not go all the way to the bottom of the channel, there is probably 1/4" to 3/8" of space at the bottom.

[Wyatt]

Originally Posted by BobC

Beautiful Eternabond job, Jim.

I agree. And nice job of tucking into that spot!

[bigb]

Been working slow and combatting the humidity (It's our monsoon season) but finally got the paint laid down and will start the Geocel tomorrow. The paint came out beautiful after one mishap with water droplets on one side that I had to completely sand down and re-do, this time with 2 inline water separators and 2 desiccant filters piggybacked onto the spray gun....no water this time. The clear coat is so shiny right now it's hard to take a picture as it is full of reflections but believe me it is so nice I am ecstatic, fixing that weathered paint has been looming over my head since I bought the rig in October last year. Cannot tell where the hole was either, the final coat of Bondo filled any air holes and feathered out perfectly. After the Geocel will come a good wash then after ample curing time for the new paint I need to buff out the rest of the roof, you can see where it is still shiny where the antenna shaded it. (Antenna is new also by the way). But before that it's time to hit the road again!

PS what do you put on the little fabric awning topper, I was thinking of putting Aerospace 303 on it. Or better just to clean it and leave it?