Use caulk while re-assembling my trailer?

[Scooter]

My p-19 trailer is disassembled and being painted. In my yard, not professionally. Because of all the rust, not for cosmetic reasons

Most of the rust was around this angle iron 'bracket' that bolts to the U channel frame and holds the leaf springs. After needle-scaling, scraping and grinding the surfaces are far from smooth. I'm guessing that there was so much rust there because of a small gap that is much bigger now.

I'm thinking of spreading some silicone caulk or adhesive there when I re-assemble it. Anyone KNOW if that's a good or bad idea?

[Charles Brennan]

Scooter, according to MrHandyman.com, "Avoid caulking any areas that can trap water or restrict its ability to escape." 
Which pretty much defines your whole boat trailer.
There is absolutely no caulk or sealants on my boat trailer as a function of rust mitigation.
I DID tape up my trailer wire connector splices, but that's it.

The Department of Energy further defines caulk usage as:
"Caulk is a flexible material used to seal air leaks through cracks, gaps, or joints less than 1-quarter-inch wide between stationary building components and materials."
Air (or water) leaks are not your problem.

"this angle iron 'bracket' that bolts to the U channel frame and holds the leaf springs." is more generally called a "leaf spring slider" and is very useful for sliding the whole axle assembly fore and aft to achieve optimum load balancing/tongue weight considerations.

Wasn't quite sure what gap around the leaf spring slider you were describing without a pic, but if you want to see a pic of a leaf spring slider with a gap, where you NEVER want to see a gap, here is one:
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My leaf spring sliders are held to the trailer frame with 4 U-bolts and shackles, since I also have fender brackets that are held to the leaf spring slider assembly.
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Having a gap where the leaf spring slider bolts to the trailer frame is not that big a deal, since the bolts and shackles attaching the slider to the frame are doing all the heavy lifting.
Listen to what you posted:
"adhesive there when I re-assemble it."
Adhesive? To adhere two different pieces of steel?

Back to Basics:
Rust is Iron and Oxygen (Iron Oxide).
Keep the Oxygen off the Iron, no rust.
Your Rust Bullet paint can do that handily and far better than "a silicone caulk or adhesive."

Hope this helps,
Charles Brennan

[Scooter]

Charles FTW again. Thank you!

Mine were not so bad as those but were close.

TBC my thinking for adhesive wasn't to hold the parts, more that caulk is flexible and (plumbing) adhesives less so. It will be bolted together as before with new grade 5 hot dip bolts everywhere so there shouldn't be too much movement and if 'filling' any gaps was a good idea (which it's not) one might be better than the other.

[Riley Smith]

Charles is right, the caulk would more likely work to your disadvantage by trapping water than it would help the situation. The paint will do more good than anything. Good luck with the finished product. I just looked  and have to break out the grinder and cutting blade to replace the light brackets. The CS bolt is corroded and it's just easier to cut it off than anything else.

[Scooter]

I'm a fan of the two-fisted breaker bar technique. 36" of leverage might not move the world but it's plenty for these bolts. : )

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