Jump to content
Huggy

Firestop Sealant

Recommended Posts

Can we have a technical discussion on sealants and their properties?

 

I am making a secondary containment box for my surge tank and attempted to seal it up with the intumescent sealant I have seen used before.  

 

It didn't work well, as seen it can be just wiped off with a finger.  This is after a week plus of dry time.

 

What is the right stuff to use?  I want it to be fire-safe and waterproof to ensure the box is completely sealed off (except for a drain out the bottom)

IMG_2594.JPG

IMG_2595.JPG

Share this post


Link to post
Share on other sites

I used the ‘great stuff’ expanding foam orange stuff for our bulkheading. Seemed to work great but I have done no testing whatsoever (for waterproofing or fire resistance). It cures hard and excess can be cut away with a knife. 
We passed tech. 

  • Like 1

Share this post


Link to post
Share on other sites
14 minutes ago, enginerd said:

I used the ‘great stuff’ expanding foam orange stuff for our bulkheading. Seemed to work great but I have done no testing whatsoever (for waterproofing or fire resistance). It cures hard and excess can be cut away with a knife. 
We passed tech. 

I used this on some house repairs on the backside of a fireplace.  I tested it with a torch.  It discolored and kinda chars, but doesn't burn.  

 

I think it probably works better than a rubber grommet.

  • Like 2

Share this post


Link to post
Share on other sites
6 minutes ago, mindspin311 said:

Hmm, not promising, I bought some of that to seal up a patch panel to block off the hole left by a heater box.

What's not promising?  The original stuff mentioned or the fire expanding spray foam?

Share this post


Link to post
Share on other sites
10 minutes ago, wvumtnbkr said:

What's not promising?  The original stuff mentioned or the fire expanding spray foam?

Sorry, original stuff. Got a tube of the same thinking it was caulking like that would cure while still being somewhat flexible.

Share this post


Link to post
Share on other sites

I have used the expanding foam as well, but bought the tube of fire block expecting it to be similar to RTV, but it turned out to be more of a cement.  I would think if you were blocking holes in a firewall and had plates with a good overlap cut you could get away with s layer of it between the patch and the panel but I wouldn't try to use it the way you would use caulking to seal up a bathroom.  I don't have a solution but I'm interested to hear what others have come up with.

Share this post


Link to post
Share on other sites

Hilti FS-1 is what I have used, not sure how it differs from what you have, but it stuck fine.  I'm thinking you might want to scuff that surface with a wire brush/scotchbright/sand paper to give it some tooth and try again.

 

The FS-1 is expected to stay put with modest use of a fire hose.  Unfortunately it is designed for buildings that usually have less vibration than racecars.

 

Pretty sure the expanding foam won't burn, but it doesn't have the expanding characteristic that the "intumescent" materials have. 

Share this post


Link to post
Share on other sites

Having to use fire stop sealants for decades as part of my day job. I always use the Hilti product line. Unfortunately it’s not usually sold at the big box stores.  The 3M product does work to seal cracks and prevent spread of fire too.  It is best to seal the bulkhead, containment box, etc as tightly as possible first. Then use the fire stop caulking to seal the small gaps. It is designed for sealing around pipes and conduits and generally doesn’t “harden” like silicone RTV.  It will work for a fire stop but in a race car it can be a challenging product to use. 

Share this post


Link to post
Share on other sites

Any downside to leaving the remnants of the intumecent in the cracks and coating the inside/outside of the seams with something that will harden and be water proof?   

 

Silicone/RTV is what I was thinking.

Share this post


Link to post
Share on other sites

I don’t see any issue encapsulating the remnants. That fire stop is a pain in the backside to clean off.   

Share this post


Link to post
Share on other sites

I used the orange expanding foam too.  You wind up tossing a nearly full bottle because it doesn't take much and the cans do not appear to be reusable.  It works great, but keep it off your skin and clothes.  Wear gloves.  

  • Like 1

Share this post


Link to post
Share on other sites

I have recieved permission to allow the used a variant the material used to wrap headers as it is heat resistant to 600 degrees F. The product is a mat that has a sticky  heat and fuel resistant adhesive backing and it cat be cut to fit with scissors or a razor blade.

 

The product brand I am familiar with is DEI i am sure their are many others.

Share this post


Link to post
Share on other sites
1 hour ago, National Tech said:

I have recieved permission to allow the used a variant the material used to wrap headers as it is heat resistant to 600 degrees F. The product is a mat that has a sticky  heat and fuel resistant adhesive backing and it cat be cut to fit with scissors or a razor blade.

 

The product brand I am familiar with is DEI i am sure their are many others.

https://www.designengineering.com/fire-tape-self-vulcanizing/ ???????

Share this post


Link to post
Share on other sites
6 minutes ago, mindspin311 said:


I don't think that's what he's referring to... I could be wrong. That's self-fusing silicone tape that's really  meant to be wrapped around something and back onto itself, where it will fuse and basically have to be cut off.  I use that sort of thing often in electrical applications on the ends of sheathing where normal electrical tape will start to unwind.

He might be referring to this sort of thing?

https://www.designengineering.com/reflect-a-cool-heat-reflective-sheets/

Edited by Slugworks Paul

Share this post


Link to post
Share on other sites
13 minutes ago, Slugworks Paul said:


I don't think that's what he's referring to... I could be wrong. That's self-fusing silicone tape that's really  meant to be wrapped around something and back onto itself, where it will fuse and basically have to be cut off.  I use that sort of thing often in electrical applications on the ends of sheathing where normal electrical tape will start to unwind.

He might be referring to this sort of thing?

https://www.designengineering.com/reflect-a-cool-heat-reflective-sheets/

That would be great for covering patch panels in firewalls where heater boxes, etc. used to be in place.

Share this post


Link to post
Share on other sites
5 minutes ago, mindspin311 said:

That would be great for covering patch panels in firewalls where heater boxes, etc. used to be in place.


For sure, the sticky backing on those is very aggressive and I've even stuck that material to the bottom of the car which gets blasted with all kinds of stuff and hasn't come off in years. You probably can't use it in lieu of the metal firewall patches on any sizeable hole per rule 9.1.7.1

Edited by Slugworks Paul
  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...