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Adding black RTV to the light bar

Ruffles

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I got my light bar installed today but I'm not happy with the caulking job done by the service center. The bead on the front isn't even even and on the back, there is a huge gap. I'd like to fill it with some black RTV but I want it to look good. If I just buy a tube and squirt it in and smooth it with my finger, I'm afraid it won't turn out. I'd be willing to buy a caulking tool if folks can recommend one and I can do a couple practice runs to get the hang of it before I go to town on my truck.

Tesla Cybertruck Adding black RTV to the light bar PXL_20250618_021025577~2


Tesla Cybertruck Adding black RTV to the light bar PXL_20250618_014356659.MP~2
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TCybertruck

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After you squirt the silicone on, use a spray bottle and mist Glass Cleaner before you smooth it with your finger.

The glass cleaner will prevent the silicone from sticking to unwanted areas and the line will be sharp. Just a tip
 

RoboTaxi

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I’ve thought about slinging this with mine. It’s adhered well but the finish of the adhesive is a little splotchy and chalking it would smooth it out.

I’m not sure RTV is the right product. I think some outdoor rated black RV chalk would be better.

Mask off the surrounding area with blue tape to help create a sharp line.
 

Electric Metal

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I got my light bar installed today but I'm not happy with the caulking job done by the service center. The bead on the front isn't even even and on the back, there is a huge gap. I'd like to fill it with some black RTV but I want it to look good. If I just buy a tube and squirt it in and smooth it with my finger, I'm afraid it won't turn out. I'd be willing to buy a caulking tool if folks can recommend one and I can do a couple practice runs to get the hang of it before I go to town on my truck.

PXL_20250618_021025577~2.webp


PXL_20250618_014356659.MP~2.webp
My recommendation is buying Dow Corning Dowsil 795. It is a structural caulk made for glass applications. I own a commercial Glazing company and this is the product that you want to use.
1st- Prep area with 99% Isopropyl Alcohol
2nd- Use Frog Tape to mask off a straight line for a sharp edge.
3rd- Apply caulk to area
4th- Tool caulk using a light mist of glass cleaner
5th- Remove tape at a slight angle toward you
Tesla Cybertruck Adding black RTV to the light bar IMG_2370

Buy one of these for tooling caulk.

Tesla Cybertruck Adding black RTV to the light bar IMG_2371
 

That Beast Mode

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My recommendation is buying Dow Corning Dowsil 795. It is a structural caulk made for glass applications. I own a commercial Glazing company and this is the product that you want to use.
1st- Prep area with 99% Isopropyl Alcohol
2nd- Use Frog Tape to mask off a straight line for a sharp edge.
3rd- Apply caulk to area
4th- Tool caulk using a light mist of glass cleaner
5th- Remove tape at a slight angle toward you
IMG_2370.jpeg

Buy one of these for tooling caulk.

IMG_2371.jpeg
This - except I would prob go with a plastic spatula or caulking tool since its against glass and plastic (unless you know how to use it well).
 
 








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