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USING RTV AS GASKET CEMENT?

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by Smokey, Jan 19, 2013.

  1. Smokey

    Smokey New Member

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    I have a new stove that uses a black rubbery RTV like substance to cement the ash pan and door gaskets. When the stove reaches 650 F or so, I get a bad smell in the house and I'm wondering if maybe this stuff is the problem. The stove has been used dozens of times so its not the paint, and the stove pipe has been in service for 10 years so I doubt it's that either. Should I scrape this stuff out and replace with new gaskets and stove cement, or is there really a rubber-like gasket cement that I'm not familar with?

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  2. begreen

    begreen Mooderator Staff Member

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    I have heard that some shops are using red RTV for gaskets. Hogwildz has put his in with RTV and seems happy with it too.

    I'm not sure what they used on your stove. What make/model stove is this? Can you add that to your signature line?
  3. Woody Stover

    Woody Stover Minister of Fire

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    The Buck 91 uses it. I got some 650* stuff at O'Really Auto Parts that I did the door gasket and ash pan gasket. I also have a caulk tube of 1000* silicone that I got at the stove store but I didn't want to open that yet. Haven't noticed any smell, maybe you are still smelling paint?
  4. begreen

    begreen Mooderator Staff Member

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    What is the hottest stove top temp that the stove has been brought up to?
  5. Woody Stover

    Woody Stover Minister of Fire

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    In my case, more like about 550, surface meter on the front like WoodpileOCD's.
  6. begreen

    begreen Mooderator Staff Member

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  7. Heatsource

    Heatsource Minister of Fire

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    some makers are using silicone- likely because their design has a small track for the gasket and it falls out all the time
    works fine up to 650 or so, then it turns to powder over time
    can make replacing the gasket a real pain!
  8. simple.serf

    simple.serf Feeling the Heat

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    I use it on draft inducer fan flanges and high power burners at work, and it seems to hold up fine.
  9. Hearth Mistress

    Hearth Mistress Minister of Fire

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    The red hi-temp RTV silicone I have here is considered safe " up to 500 degrees". I have used it in a pinch when a small section drooped down but it does stink after a while. The stove gasket cement I use is $8 and is rated up to 1,000 degrees. I just used a wire brush, scraped it out and replaced the whole thing. Gasket was $6 so for $14 it was done right, and more importantly, no more stink!
    PapaDave likes this.
  10. Woody Stover

    Woody Stover Minister of Fire

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    When I re-did the door gasket on the Buck (2008 stove,) that stuff was still in great shape; Pliable, and looked like it was put on the day before. That stuff was tough, too. I had to work to get it off. Maybe they use 1000* silicone, or the door never got up to 650.
  11. rideau

    rideau Minister of Fire

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    Woodstock is certainly using a black gasket glue for some of their gaskets. They just sent me some for my cat gasket.
  12. Smokey

    Smokey New Member

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    I've had the stove up to 700 about a dozen times, 750 once. I hadn't seen a silicone that would withstand 1000* but I would hope that this is what is used on a stove that is designed to see 700 degrees during normal operation. I guess the only way I'll know for sure if this is the problem is to replace it with gasket cement. Like Woody said, this stuff is tough to get off!
  13. slindo

    slindo Member

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    Another thing about silicones is they "poison" any surface they have been used on for other sealants, by leaving residue that prevents other sealants from sticking. So if you have used silicone on a surface, and want to try something else, you got to clean the heck out of it using MEK or abrasion or both.
    Personally I would not use a silicone sealant on a stove unless it was recommended by the stove manufacturer, and I had the specific brand that was recommended. Woodstoves get a lot hotter than car engines.
  14. Hearth Mistress

    Hearth Mistress Minister of Fire

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    If you have a dremmel tool, there are a few different tips that you can use to make an easy job of getting the gunk out. It's better than a screw driver and wire brush ;)
  15. Smokey

    Smokey New Member

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    Thanks all for the tips. I know that you need to be very careful with silicone mold release so that you don't contaminate your work surfaces, but it didn't occur to me that RTV could have the same issue's. Good to know.
  16. Hogwildz

    Hogwildz Minister of Fire

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    Never had any of those issues with silicone on the Summit. Now thew Rutland gasket cement, that is another story.
  17. Hogwildz

    Hogwildz Minister of Fire

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    Your fine using silicone. I have used it, and also it cleans just fine. Use a wire wheel and clean it off with some brake cleaner or rubbing alcohol, and it will hold just fine.

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