How to deal with body seam putty and rust?

[RenoHuskerDu]

I'm going to apologize for posting this here, because I'm working on my E99 550, not a Bullnose.  But I suspect that the talent pool for this rust issue is deeper here than on FTE, where I have zero replies to my thread so far (https://tinyurl.com/wxntny2).

The question is how to best deal with rust that has crept under the body seam putty on the floor, see pic below.  Unless I hear contrary advice, I plan to

1. pull up the putty until I get to unrusted metal
2. dose it with phosphoric acid to convert rust
3. reapply some leftover windshield Butyl as putty
4. paint it all with oil-based rust-preventative enamel

We have mostly dry weather and absolutely no road salt in Central Texas.  Does this appear to be a reasonable course of action to y'all?

FRfloor.jpg

[ArdWrknTrk]

I'd probably use a hook scraper to pull out as much seam sealer as possible.
Then hit it with a wire brush on an angle grinder.

Ospho doesn't need to go over rust.
It works on clean steel too.

I've never tried windshield adhesive as seam sealer.
Let us know how it works out!

[Rembrant]

RenoHuskerDu wrote

Does this appear to be a reasonable course of action to y'all?

Yes. I like using a knotted cup wheel wherever I can...



A regular wire wheel on a drill is great too. I've put thousands of miles on them...lol.

Another one that works wonders for removing paint and loose rust is a strip wheel. I've used these with great results as well. Available at Home Depot. You can get them for grinders or drills.



Remove loose paint and rust, get it good and dry, then apply Ospho or whatever your rust converter of choice is.

[Danny G]

I like those knotted cup wheels too, hold up better than the crimped wire ones.

Another good one is the flapper disks.

[ArdWrknTrk]

Flap discs are good for leveling metal but they're doing nothing for rust pitting or down in the pinch weld.

Husker du is pulling dum dum out of a seam.
He needs to get the loose rust out of there and treat it.

[RenoHuskerDu]

Indeed, I keep a box of flap disks on hand and use 'em often, but here they wouldn't fill the bill. I'll use hand brushes, and a the other tools shown above.

Temp's finally up to 50F so I'm going out now to attack the carpe diem, as it were.

You guys up in the freeze belt are laughing at me, I know....

[FuzzFace2]

RenoHuskerDu wrote

I'm going to apologize for posting this here, because I'm working on my E99 550, not a Bullnose.  But I suspect that the talent pool for this rust issue is deeper here than on FTE, where I have zero replies to my thread so far (https://tinyurl.com/wxntny2).

The question is how to best deal with rust that has crept under the body seam putty on the floor, see pic below.  Unless I hear contrary advice, I plan to

1. pull up the putty until I get to unrusted metal
2. dose it with phosphoric acid to convert rust
3. apply brush on seam sealer - SEM makes a good one I used on my project
4. paint it all with oil-based rust-preventative enamel

We have mostly dry weather and absolutely no road salt in Central Texas.  Does this appear to be a reasonable course of action to y'all?

FRfloor.jpg

I FIXED it for you
The first coat of seam sealer was from a tube and caulk gun. Let set up a day or so and used the brush on over the top of the tube stuff.
I did this top & bottom of the floors, rockers, etc.

Then did 2 coats of Duplicolor roll on bed linertop & bottom

Dave ----

[RenoHuskerDu]

I'm liking that seam sealer in a tube. The windshield stuff requires heating first nearly to 100F. Did you find it at NAPA?

As for the bed liner coat, although that really appeals to me for its durability, it wouldn't work for me as I plan to lay B-Quiet B-Quiet web site down over the paint, so it needs to be smooth in order to adhere well.

[RenoHuskerDu]

Goes on like water, easy to use. I'm pleasantly surprised with its low price too, $25/gallon, probably because
the cattle ranchers use it a lot for pipe fence, bale feeders, etc. This is cattle country.

I'm checking my local NAPA to see if they have body seam putty in a tube.

[reamer]

Ya really need to get down to clean metal, encapsulating rust, is still rust...

the cleaner the better, all rust on mine rest was cut out...

[ArdWrknTrk]

It's not encapsulating anything.

It's burning rust up and turning it to insert iron phosphate.
Just like (similar to) Parkerizing a gun.

[FuzzFace2]

RenoHuskerDu wrote

I'm liking that seam sealer in a tube. The windshield stuff requires heating first nearly to 100F. Did you find it at NAPA?

As for the bed liner coat, although that really appeals to me for its durability, it wouldn't work for me as I plan to lay B-Quiet B-Quiet web site down over the paint, so it needs to be smooth in order to adhere well.

The NAPA is a loaded question thing LOL

I first started getting my body supplies from a Car Quest that did body supplies but they sold out to a NAPA that moved down the street and no longer carries body supplies.

I then had to go to the next town over to the NAPA that carries body supplies and where I get all my auto primer & paint from.

I like the tube / gun as you can squirt it into the cracks "sealing" them. I then went over that with the brush on to make it look like factory done sealer.
Thing is if you don't need a full tube how long will it last? I used most of the tube and I am sure by the time I need it again on the next project it will be hard. The brush on, comes in a can, was still good a few months later when I needed to hit some other areas.

3M also makes a Drip Check sealer in a small squeeze tube, like weather strip glue, you can squeeze into cracks and then use the brush on seam sealer.

Might try on line for the SEM sealer if you cant get it local, like Amazon?
Dave ----

[RenoHuskerDu]

Is it the collective wisdom to first apply the body seam putty, then paint?

Or vice versa?

I ordered 3M Dynatron Auto Seam Sealer Caulk, 550, Grey, 12 oz caulking gun tube.

Waiting for a couple dry days to proceed, truck is under carport but this cold rain is sideways recently....darn Canadians sent their weather down to TX, lol, or it was AlGore

[ArdWrknTrk]

I try to apply DTM etch primer, then seam sealer, then whatever top coat system over that, once it has dried or cured.

I personally feel that an acid catylized etch epoxy primer over clean metal is going to be the best bond and corrosion protection you can get.

[RenoHuskerDu]

Thanks, Jim. I am fighting like mad to suppress my CDO that would drive me to do a perfect job.  I have to keep telling myself "you have n trucks, 4 of which are non-running projects, do you really need this work truck to be perfect?" and sometimes I listen to myself. Sometimes.