RTV setup time

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Not that it's super relevant, but the door gasket material in the oil boiler refractory replacement kit I installed this Fall had adhesive already on the gasket-you just peeled it off.

All the boiler doors I do have that sticky back but I just use red devil high temp silly cone I don't trust tape. Red devil industries red , I use it to seal all chimney joints and put in the rope/flat gaskets. Never have had an issue with it not taking the heat.
 
My only experience with RTV on a stove gasket was with blue Permatex. I got it for its high te.p rating. Big mistake. It set up like stone and was near impossible to remove. I checked and Permatex red is rated at 600F. If that works well for holding AND removal then that is what I'll use. Heading into Seattle for the proper gasket material now.
Got an angle grinder? With a cable-twist wire wheel, you'll be done cleaning that groove in under 10 minutes. While you've got it, enjoy that heat in the car. ;lol
 
Stove shop that had the gasket says they only use Rutland gasket cement. Checked a new morso while there. It had silicone
 
Stove shop that had the gasket says they only use Rutland gasket cement. Checked a new morso while there. It had silicone
Did they give you any reasoning behind that verdict?
 
Everybody is using silicone from the factory these days that I have seen. Fills more completely and if the door frame gets over six hundred you have more problems on your hands than the door.
 
Everybody is using silicone from the factory these days that I have seen. Fills more completely and if the door frame gets over six hundred you have more problems on your hands than the door.

Voice of experience -- knows the vaporization temps too!:p:)
 
Voice of experience -- knows the vaporization temps too!:p:)

Yeah a few years ago a member posted that he had sealed the pipe connection on his free stander in his fireplace with silicone caulk. I spoke of the vaporization thang.

Shortly thereafter he posted about sitting in the room when the stuff went "poof" and stank up the joint.
 
One thing is not to go by the color of the RTV but go by the specs. Different manufacturers do different colors and some different colors in various formulations. I have always been fascinated by the various heat ranges on 100% silicone. It all vaporizes between six and eight hundred degrees.
Yes, for posterity sake it would be helpful to others to get the exact product and product number being used successfully by the pros and stove mfgs..
 
unless it glues the door to the stove you will be fine yes. It can and does happen sometimes.
That is tough to do on a Summit, It has a knife edge, so you would literally have to have an inch or more round bead of ooze to glue the door shut.
 
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Did they give you any reasoning behind that verdict?
Because it has worked for them. After I pointed out the silicone (black) on the Morso he said to let him know if I can find out specifics used by the stove manufacturers.

I ended up using Rutlands because after 3 stops no one had red permatex, including home depot. That and our hvac has been running non-stop and needs a break. I removed the door, put the Rutland in the channel, then seated the gasket. Put the door back on, closed it for a minute, then left it open for an hour. Now I am doing a break-in fire, no hotter than 500F stove temp per directions. Will fire it up for real tomorrow.

A while back webby3650 said he didn't like Meeco's gasket adhesive. Looks like he was right. The Rutland has a much more homogenous mix, not watery. I also got some better high-density 5/16" gasket from the local dealer. Much nicer than what I replaced.
 
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Because it has worked for them. After I pointed out the silicone (black) on the Morso he said to let him know if I can find out specifics used by the stove manufacturers.
I guess it's possible they could use something like MilPac...1100-degree stuff. Silicone is stock on the Bucks as well. I guess it would depend on the design of the stove in question, but I never saw more than a couple hundred degrees on the Buck door. The frame couldn't be hit by direct radiation from the fire...the front of the stove shielded it.
I ended up using Rutlands because after 3 stops no one had red permatex, including home depot.
Auto parts stores had no high-temp silicone?? That's nutty! :confused:
A while back webby3650 said he didn't like Meeco's gasket adhesive. Looks like he was right. The Rutland has a much more homogenous mix, not watery. I also got some better high-density 5/16" gasket from the local dealer. Much nicer than what I replaced.
The Meeco is also "stove sealer" according to the label, and I have used it for that. Seemed to me that the thinner consistency would get into the seams and seal better...I don't know.
So, is the new stuff graphite gasket or what? What was the old stuff you had in there, just generic stove-shop stuff, and do you think that may have contributed somehow to the failure? How long did it last?
 
The problem is that millpac is non adhesive
OK, then I misunderstood what Mill-Pac was. I thought it was similar to this, which I picked up at a stove shop a couple years ago but haven't used yet. Might be shot by now...:(
[Hearth.com] RTV setup time [Hearth.com] RTV setup time
 
begreen, back when I was keeping up with door gaskets on those antique Jotuls (four doors per stove x 3 stoves = 12 door gaskets!), I was also using the Rutland gasket cement. I didn't love it, but it does work. Getting it off the iron was always frustrating, tho... either chipping it away with a screwdriver or making a dusty mess with grinders and other means (Google silicosis).

I've always wondered about the high temp RTV's, that I've seen others mention. How does one completely remove the old RTV from the stove, when doing a gasket replacement? At least on the Jotul design, getting everything down to bare metal was imperative for getting the new gasket to bed nice and flat, lest you have a leak with those wimpy 1/4" braided gaskets.
 
begreen, back when I was keeping up with door gaskets on those antique Jotuls (four doors per stove x 3 stoves = 12 door gaskets!), I was also using the Rutland gasket cement. I didn't love it, but it does work. Getting it off the iron was always frustrating, tho... either chipping it away with a screwdriver or making a dusty mess with grinders and other means (Google silicosis).

I've always wondered about the high temp RTV's, that I've seen others mention. How does one completely remove the old RTV from the stove, when doing a gasket replacement? At least on the Jotul design, getting everything down to bare metal was imperative for getting the new gasket to bed nice and flat, lest you have a leak with those wimpy 1/4" braided gaskets.

You'll find that on the BK door gaskets that the door glass studs and nuts actually reside UNDER the door gasket. Big huge bumps that create high spots for the door gasket that must either be absorbed by the 7/8" thick door gasket or filled with the RTV. Since these huge bumps are part of the design I will not worry about creating a nice and flat gasket channel. It's impossible. I worry more about new RTV sticking to old RTV.

I would never look for high temp RTV at the hardware store. It's an automotive store item. Schucks, Oreileys, autozone, napa, etc. one on every corner.
 
All this running around posting and stihl no firm answer. I'm sticking with Rutland....for now even though it gets on my nose.
Earth to BKVP and other manufacturer reps out there---Hello!!! : what do your stoves use for gaskets ?
Now for the engineers among us, and stove designers: how about just plain doing away with loose, replaceable gaskets altogether ? How about
what's used to seal pressure vessels ( like subs, engines, rockets ), or car doors and windows ? Is there a permanent gasket material like the 'rubber' compounds that will take high heat ?
For all the effort we put in to re-do gaskets, I'd pay the extra $$$$ to have a permanent sealed opening(s).
BTW, RTV is tough stuff used primarily on engine components. Read the tube, don't get it on the nose.
 
My only experience with RTV on a stove gasket was with blue Permatex. I got it for its high te.p rating. Big mistake. It set up like stone and was near impossible to remove. I checked and Permatex red is rated at 650F. If that works well for holding AND removal then that is what I'll use. Heading into Seattle for the proper gasket material now.

I read your other posts and it seems this is too little too late, however for others with the same question I'll give my two cents. Again I'm a mechanic, not a stove guru, but I've rebuilt a lot of engines and transmissions. Permatex is my very good friend. The red variety holds up to many heat cycles (engine achieving operating temperature and then sitting over night - holding for 15 years + on many of my applications) My air cooled engines run 100k + miles with no leaks or problems due to heat and these engines routinely run at ~ 350 - 400 degrees. The engine seals are shockingly close to the exhaust which achieves 600 degree temps when operating. When I scrape them off to redo the seals they are always pliable and squishy still. Scrapes off with a plastic scraper very easily, just takes a little time to get all the little bits that fill in imperfections in the mating surfaces.

I've also used this to repair vacuum lines and other rubber components in a pinch (spread a little rtv around the worn hose, place a patch of rubber over the problem, hose clamp in place.) So my experience is that it's a very good adhesive and a quality product. Again I don't know a lot about stoves, but I've worked with RTV a ton. Hope this helps some people.

The types that get brittle are the window sealants. If you want it to stay squishy get the kind for engine seals. At least this is the case with Permatex brand. Also the "stronger" the window sealant, the more brittle it is. That's the trade off. So I'd steer clear of that type of silicone.
 
I'm going to try and get specifics from stove companies about the RTV they are using to take the speculation out of the process. My experience with Permatex Blue (automotive) silicone was a bust. Permatex red seems a better choice and is rated at a higher temp.

@BKVP What specific brand and product does Blaze King use and recommend for stove door gasket adhesive?
 
Has anyone here done a tutorial with pictures on how to properly replace a door gasket? I know there are a lot of different door designs, but the general idea should be the same. My Summit has 3 years on the original gasket, and I'm sure it could stand to be replaced.
 
I posted a youtube video a short while back that was decent, will try to find.
 
I'm going to try and get specifics from stove companies about the RTV they are using to take the speculation out of the process. My experience with Permatex Blue (automotive) silicone was a bust. Permatex red seems a better choice and is rated at a higher temp.

Temperature range -65°F to 500°F (-54°C to 260°C) intermittent; resists auto and shop fluids. - See more at: (broken link removed to https://www.permatex.com/products/gasketing/gasket-makers/permatex-sensor-safe-blue-rtv-silicone-gasket-maker/#sthash.fcSKzzx2.dpuf)

Taken from Permatex's site. There's that pesky word, "intermittent" in there. They don't really specify what that means, but I've found it to mean it fails if it gets too hot. "failing" can mean a lot of things to me. Not retaining fluid, no longer bonding to a surface etc. That's why I always use the higher temp rated product for my needs. If I run an engine too hot I have a problem. If the seal leaks and I lose oil pressure as a result I have a much much bigger problem. Don't really know how this applies to stoves - other than you said it cracks and becomes brittle. Seems like a problem.
 
Has anyone here done a tutorial with pictures on how to properly replace a door gasket? I know there are a lot of different door designs, but the general idea should be the same. My Summit has 3 years on the original gasket, and I'm sure it could stand to be replaced.
Recommend you buy the gasket from a good PE stove dealer so that you get the right material and size. You can order from www.chimneysweeponline.com if none in your area. This video goes over the basics for using Rutland gasket adhesive. The example is an old Fisher stove but the principal is the same.
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Thanks begreen, that was informative. Will have to check the manual to see what size gasket my Summit takes. Hopefully mine makes it till Spring, the sound of my furnace gives me night terrors.
 
Temperature range -65°F to 500°F (-54°C to 260°C) intermittent; resists auto and shop fluids. - See more at: (broken link removed to https://www.permatex.com/products/gasketing/gasket-makers/permatex-sensor-safe-blue-rtv-silicone-gasket-maker/#sthash.fcSKzzx2.dpuf) Don't really know how this applies to stoves - other than you said it cracks and becomes brittle. Seems like a problem.

The blue rtv didn't crack or become brittle. It set up like epoxy cement and was a real bear to remove when the gasket was due to be replaced.
 
The blue rtv didn't crack or become brittle. It set up like epoxy cement and was a real bear to remove when the gasket was due to be replaced.
I haven't seen either the red or the black silicone get hard like epoxy. Here is the stuff I used on the Buck, and when I re-did the gasket later, the sealant was still pliable, not hard like you are describing. It's possible that your stove design allows the door frame to be hit directly by radiation, in which case it might get too hot for the epoxy to work. I shot the Buck door with an infrared thermo on occasion and IIRC, it was 200 or a little over. The front of the stove body completely overlapped the door frame, shielding it from direct radiation.
This is the last stuff I used, Versa-Chem Black, from O'Reilly. http://www.itwconsumer.com/versachem-products/product.cfm?id=Mega Black Silicone O.E.M., 3 oz.-157