Sanding/Treating rivetheads before Seam Sealer

[Phoebus]

Hey Everyone. I am planning to put some seam sealer down on top of the roof at the joints and rivet lines but I was wondering if it is necessary to sand down or convert the rust on the rivet heads before putting down seam sealer?

After that we are going to lay down our Henry’s roof paint!
For the Henry’s application, does the current white roof paint need to be sanded down to metal or just roughed up a little bit?

Thanks all!

 

[family wagon]

If you want any coating to stick to those rusty rivet heads they'll have to be cleaned up. Wire brush at least (I'm thinking a wire wheel or cup brush in an angle grinder or maybe a drill, actually). It's hard to clean a rivet head by any means except media blasting because the head is domed and it's down in a dimpled depression in the metal. Brush to remove loose stuff followed by an acid converter might work; I haven't tried that.


As to removing the white paint: I think it depends on how well the existing paint is bonded. On my bus the roof paint was peeling off the primer. Big spots were missing, but the metal hadn't rusted because the primer was intact. I sandblasted the whole roof, and while doing it, sometimes saw chunks of paint as big as a quarter breaking off. If your paint is still bonded well then a simple wash, degrease, and scuff may be all you need.

 

[EastCoastCB]

wire brush on a drill will knock out that rust on em. But then you'll need to sand a bit then paint.

 

[Phoebus]

Thanks familywagon and EastCoastCB!

Awesome, I’ve been wanting to use a cup brush on something! I’ll try one out with my angle grinder or drill.

Our paint is in very good condition on top, no peeling or chipping of any kind so that’s good news. For the degrease, should we use acetone or mineral spirits or denatured alcohol or something else?

 

[Phoebus]

wire brush on a drill will knock out that rust on em. But then you'll need to sand a bit then paint.

Also, super lucky to doing the build in Florida so we can do projects like painting and spray foam even during the winter! :biggrin:

 

[tugboater-SKO]

Hey Everyone. I am planning to put some seam sealer down on top of the roof at the joints and rivet lines but I was wondering if it is necessary to sand down or convert the rust on the rivet heads before putting down seam sealer?

Thanks all!

Probably a good idea to clean those up before coating. Our factory seams didn't leak (only my own did), but looked just like yours. I dug out the old sealer as best i could then laid a couple beads of new stuff. After it cured I rolled a strip of Flex Seal over them. We still need to paint the roof, but when the time comes we'll use a marine maintenance enamel for that.

 

[EastCoastCB]

Also, super lucky to doing the build in Florida so we can do projects like painting and spray foam even during the winter! :biggrin:

Yep. Sure is nice here.

 

[musigenesis]

The rivets on the back of my bus were all rusted pretty severely. I removed the paint from all of them and the skin around them with a painter's tool, then treated them with Ospho a few times, cleaned and painted with POR-15 (which adheres extremely well to post-osphoed pitted metal).

 

[lebusmagique]

Probably a good idea to clean those up before coating. Our factory seams didn't leak (only my own did), but looked just like yours. I dug out the old sealer as best i could then laid a couple beads of new stuff. After it cured I rolled a strip of Flex Seal over them. We still need to paint the roof, but when the time comes we'll use a marine maintenance enamel for that.
View attachment 39811

Uhhh was this Flex Seal Liquid? I saw this post and thought "hey that's a good idea!"

Did it last night and realized today it can't be painted over.........

I'm so screwed.

 

[musigenesis]

Uhhh was this Flex Seal Liquid? I saw this post and thought "hey that's a good idea!"

Did it last night and realized today it can't be painted over.........

I'm so screwed.

Heh, had a couple seconds of "hey, some guy on reddit just did the same thing!"

 

[JDSquared]

Heh, had a couple seconds of "hey, some guy on reddit just did the same thing!"

You're not alone!

 

[lebusmagique]

Yep that's me. I managed to get it all off thankfully. Just used my pressure washer and peeled the paint off with it. That's what I get. Curious about what this guy's plan is though? Is he going to do his whole roof in the flex seal?

 

[Native-SKO]

We used EternaBond to seal the seams. That stuff works well. Comes in 4" wide and 6" wide rolls.

 

[banman]

We used EternaBond to seal the seams. That stuff works well. Comes in 4" wide and 6" wide rolls.

Can you get SUPER specific on which product you used -- looks like EternaBond comes in 100 flavors!

Did you then paint over the eternabond tape? (assuming you've painted your roof white for TX/FL living...)

 

[Native-SKO]

Can you get SUPER specific on which product you used -- looks like EternaBond comes in 100 flavors!

Did you then paint over the eternabond tape? (assuming you've painted your roof white for TX/FL living...)

EternaBond RSW450 (4 inch wide) and RSW650 (6 inch wide). In some places I split the RSW650 down the middle to make 3 inch wide strips. After that I rolled 3 coats of Ames Maximum Stretch Elastomeric Roof Coating with Hi-Tech ceramic beads added into the elastomeric paint. The result is a tough coating that is similar to Rhino coating. It does not stay real clean due to the ceramic beads. It does wash off fairly easily.

 

[Native-SKO]

Note: I had to remove a lot of silicone caulk as neight the EternaBond nor the Ames elastomeric paint will stick to silicone,