High-temp/flame resistant coatings for rocket interiors?

[SolarYellow]

I often see builds where people smear JB Weld all over the inside of something that needs to stand up to ejection charge heat. It's heavy and looks like heck and I hate it.

I'm thinking a lot about gap staging and other setups where a lot more structure than normal will see ejection charge, and started thinking about alternative coatings that would be more like paint, capable of sealing the cardboard and wood against high temps while keeping it lighter, neater, and not screwing up dimensions.

Found this thread discussing header paint:
https://www.jalopyjournal.com/forum/threads/best-header-paint.1141405/
I think this would probably be the ultimate, but it's $50/gallon to buy surplus leftovers on fleabay:
https://spinoff.nasa.gov/spinoff1996/67.htmlBTW, "siloxane" is a chemist's term for what us normal people call "silicone."

ETA: Further checking indicates the $50/gallon price is only one part of the two-part system, so it's really hundreds of dollars for price of entry. Can reasonably cross this one off any list I'm going to make.

Related search led to this discussion of Thermalox and Stove Bright:


Thermalox is at least a silicone-based resin. Best shipped price I can find is here:
https://www.fire-parts.com/products/thurmalox-satin-black-stove-paint?variant=29932056641622
Stove Bright is here:
https://www.amazon.com/gp/product/B0052SWYZY/
Also mentioned in the HAMB thread is the classic VHT:
https://www.oreillyauto.com/detail/...roof-11-ounce-aluminum-spray-paint/vht1/sp117
And of course, there's always the lowest-price point of entry, the Rusto BBQ paint:
https://www.homedepot.com/p/Rust-Ol...terior-Exterior-Spray-Paint-7716830/100165100
Has anyone else tried these options as alternatives to the soul-destroying JB Weld smear?

 

[mh9162013]

I've found that generic/off-brand white glue from Dollar General has been effective to protect cardboard interiors from ejection charges. It's not the same stuff as Elmer's white glue as it leaves a somewhat rubbery and very clear coating when dry. I've seen it hold up fairly well in my 18mm removable baffles with no issues.

I agree, don't use JB Weld. I've found that it tends to bubble up and pull away from cardboard with high heat. Then there's the fact that it's less convenient to use and far more expensive than my other alternatives like the Dollar General white glue.

 

[jsdemar]

Sodium silicate (water glass).

 

[Hobie1dog]

VHT header paint, the industry leader for years at your local auto parts store.

 

[David Schwantz]

https://shopbvmjets.com/index.php?main_page=product_info&products_id=29

 

[jsdemar]

https://shopbvmjets.com/index.php?main_page=product_info&products_id=29

It's sodium silicate.

 

[David Schwantz]

Ok. I have used this for 20 years on turbine models. They also make a ceramic blanket.

 

[SolarYellow]

https://www.homedepot.com/p/Rutland-1-Gal-Water-Glass-Cement-Floor-Sealer-Gallon-Jug-146/300981927

 

[Capt. Eric]

I don't know what you're building, but... Not sure why you are so worried about the appearance of a section that won't see the light of day once assembled. Also not sure why you would replace adhesive with paint. Paint doesn't hold parts together very well. And it doesn't insulate very well, even if it does stand up to heat, so it may not do what you think it does. Finally, the heat inside a rocket is not as high as, say, the Space Shuttle nose during reentry. Shouldn't have to get so exotic with your materials.

Sometimes people over think things. Work neatly, and with care, and it should look and perform well.

Than again, to each his/her own, so knock yourself out.

 

[manixFan]

I use a rolled up sheet of paper cut to the right dimensions to fit inside a body tube I need to protect. Works great and is easily replaced when needed. Paper is a good insulator and about as cheap as it gets. Blue tape also works well to cover areas that need protection – I just fold a corner over so it’s easy to remove.


Tony


Tony

 

[user 30299]

I use a rolled up sheet of paper cut to the right dimensions to fit inside a body tube I need to protect. Works great and is easily replaced when needed. Paper is a good insulator and about as cheap as it gets. Blue tape also works well to cover areas that need protection – I just fold a corner over so it’s easy to remove.


Tony


Tony

Simple is always good . . .