Just Butyl Tape Or More ??

[mitch]

Hello everyone ! This weekend we finally had warmer weather to start our renos on our 1980 Bigfoot. First we removed the awning and the awning rail from the fuselage. Then we removed all the old butyl tape and silicone that the previous owners had piled on top...It took some time and a little elbow grease but it turned out great...We then filled some of the extra holes that had been hidden behind the rail that someone had hoped would not leak . It did and now we are going to reinforce a wall that has some delamination.....!! BUT the worse was yet to come. Once we removed the metal plates that held the bottom of the of the arm rails we found some BIG holes !!! We did our first fiberglass repair and covered two golf ball size holes. So here's my question. Once we have the wall ready ( sanding etc completed ) and we are ready to put the metal plates back on should we put some kind of adhesive on first then butyl tape ?? We know it needs to be strong...Will the butyl be enough ?? Any suggestions ? Thanks so much ! Happy trails Mitch

[Herb P]

So here's my question. Once we have the wall ready ( sanding etc completed ) and we are ready to put the metal plates back on should we put some kind of adhesive on first then butyl tape ?? We know it needs to be strong...Will the butyl be enough ?? Any suggestions

Butyl tape is the worst abomination from the 70's and should no longer be used. What happens is you put butyl tape under something, then rivet it on. Years go by and regular use causes the butyl to get squeezed out from between but the rivets don't tighten up. Then what you have is additional space that water gets into.

My first mission in restoring a trailer is to remove everything that has butyl tape under it and clean it off entirely. To seal stuff correctly, use modern technology. I prefer to use automotive seam sealer. It's meant for exterior use, doesn't shrink over time, stays flexible, paintable, and is also meant for use in a vibration environment (as opposed to household caulking junk like Mono, etc). Silicon is almost never the right goop for the job.

Also, don't just goop the caulking on. Mask all around where you're going to spooge the stuff, then affix the item in question, and peel the tape off leaving a nice clean line where the sealant ends.

[Darrel Smith]

This raises a question about sealing windows. I have used putty on my windows like the origional set up. Others on the forum have suggested using butel tape for this. I thought about using butel calk. Is the automotive seam seal a better choice?

[Herb P]

This raises a question about sealing windows. I have used putty on my windows like the origional set up. Others on the forum have suggested using butel tape for this. I thought about using butel calk. Is the automotive seam seal a better choice?

That's what I've used on the windows of 2 trailers now. The first trailer I did about 5 years ago and used automotive seam sealer on all the windows. Still no leaks when I sold it earlier this spring. I'm now doing my 17 with seam sealer as well... I refinish toyota land cruisers as another hobby and those things are a high vibration environment and seam sealer has never let me down between body panels. (my painting skills on the other hand ...... )

Just this weekend, during the rain, I noticed that most of the rivets on my awning rail were leaking. So I pulled the awning rail off. However, as I was doing that, I noticed light shining through the middle of one of the rivets. So the leaking was happening through the center of the rivet not around. So after I removed the awning rail, cleaned up the old crusty butyl, I used seam sealer the whole length of the awning rail plus covered each new rivet hole with seam sealer as well... Who knows how long it had been leaking water in behind the foam insulation?

There are waterproof (sealed) rivets but I couldn't find any the last time I was out shopping.

[Darrel Smith]

Herb
seam sealer sounds like the way to go. We don't get much rain here in nevada but I have noticed the putty is cracking around my windows so I need to redo them again before I go where it is raining. Will the seam sealer hold on wider joints also?

[Herb P]

Herb
seam sealer sounds like the way to go. We don't get much rain here in nevada but I have noticed the putty is cracking around my windows so I need to redo them again before I go where it is raining. Will the seam sealer hold on wider joints also?

Well, it's primary function is to seal between body panels so those gaps are often some number of mm wide... So yeah, it does ok as far as I've been able to tell. I use the Dominion Sure Seal brand but I think they're all probably comparable.

[brendadave]

I use the Dominion Sure Seal brand but I think they're all probably comparable.

I have not seen any Auto Seam sealer anywhere in my travels. Where/what kind of store are you buying it from?

Thanks

P.S. I have to redo my awning rail and drip rail over the door, what size of rivets did you use?

Thanks again!

[Herb P]

I have not seen any Auto Seam sealer anywhere in my travels. Where/what kind of store are you buying it from?

P.S. I have to redo my awning rail and drip rail over the door, what size of rivets did you use?

Well, _any_ automotive body shop supply store will have it. That includes "Napa CMax" but I think I saw some at Canadian Tire last night (they carry other Dominion Sure Seal products in the auto body aisle... It comes in a caulking gun tube.

Last time I was up in Edmonton, you couldn't swing a dead cat without hitting an auto body supply store. Just ask for "seam sealer".

[Herb P]

P.S. I have to redo my awning rail and drip rail over the door, what size of rivets did you use?

oops. I forgot to answer this q. I just used the rivets that went into the holes the tightest. I don't remember specifically. They were the aluminum variety. I recommend buying a collection of aluminum rivets of various thicknesses and lengths.

[brendadave]

Last time I was up in Edmonton, you couldn't swing a dead cat without hitting an auto body supply store.

I guess that was my problem, I don't have a dead cat...plenty of dead mice though

Thanks for the suggestions.

[Brian B-P]

In his post about a Lander restoration, "...a fiberglass renewal", Rob linked to a page showing an automotive sealant being used on the trailer; he also supplied some more detail about the sealant, which was apparently Dow's Betaseal.

I have not used a product like this, but Herb's proposal to use the modern technology which works so well on cars makes sense to me. I don't know enough about the specific products to know if the Dow urethane or one of the many Dominion Sure Seal products is appropriate in this particular case, but I'm guessing one of them would be. On my own Boler, I have generally used butyl caulk tape, which is at least a bit adhesive and elastic, so it might have some hope of working better than that old plumber's putty.

I think the task of forming a gasket between mating surfaces (such as between a plate and the body) is fundamentally different from sealing a gap, or making a waterproof layer over a joint; common RV practice uses putty in the gasket situation, various caulks for gaps, and some weird stretchy slathered-on stuff to cover joints (and rivets). In cars, urethane and silicone sealants form gaskets, seam sealers for gaps, and there are no layers of stuff slathered over the outside of the car (unless you count undercoating).

I guess that was my problem, I don't have a dead cat...plenty of dead mice though

So you must have a live cat, because if you had no cat, you'd have live mice... but no rats, since this Alberta.

[Ed Harris]

I keep reading this thread over and over and I just have to wonder if we are all really discussing the same thing????

Every experience that I have had with Butyl Rubber has been the opposite of what is being described here?

This topic does entirely remind me though of the Putty Tape that was the typical sealing material from the 60's until the development of Butyl Rubber somewhat more recently.

There are still a lot of manufacturers and servicers using the Putty Tape but from what I have seen and learned it simply deteriorates as is being blamed here on Butyl Rubber?

Sooooooooo I wonder if maybe the two names are being interchanged here thus giving Butyl a bad "Name"?

When I have used Butyl Rubber I have been entirely impressed with its anbility to seal and conform to odd contours as well as its resistence to the elements and temperature extremes.
These are all traits that the Putty Tape lacks.
Further I feel the Rubber has an elasticity and durability that nothing else I have used has.

I have not used the seam sealer being discussed here but it certainly stands to reason that it would work as it is designed exactly for the types of applications we a re talking about.
As long as it is formulated to stick to Fiberglass, I will be looking into it myself.


So again I will ask,Are we really speaking ill of the Butyl or of Putty?

Inquiring minds want to know?

Ed

[Herb P]

There are still a lot of manufacturers and servicers using the Putty Tape but from what I have seen and learned it simply deteriorates as is being blamed here on Butyl Rubber?

Sooooooooo I wonder if maybe the two names are being interchanged here thus giving Butyl a bad "Name"?

I think you're right. I'm speaking ill of the grey butyl putty tape and its distant cousin the black putty tape (not sure what it's made of)...

I don't think I've ever encountered 'Butyl Rubber tape'.

The problem that I see with any sort of 'putty tape' is that it is used as a compression seal. ie: you stick a thick blob of it between 2 things. Then you fasten the two things together and the stuff compresses and oozes out from between the two things. Then you cut the rest away and everything is sealed, for a few years. As the 'thing' is used over the years, people lean against windows, or you wiggle that hose in the side of the trailer, etc... Things get compressed and decompressed. When things get compressed, the putty oozes out a little more eventually creating a gap on decompression and you have a new leak. You really have to use a flexible sealant that can move with the times... Maybe this Butyl rubber stuff returns to its original shape after it is compressed? I don't think I've seen it.

[Con]

This topic has been hashed over numerous times.
We have to be very clear about the products discussed as there are so many to chose from.

http://www.fiberglassrv.com/board/index.ph...18751&st=15
Specifically:

For those of you that need to know or want to know here are a few sites to read up on Butyl Tape.
Quote:"Butyl is a common term used for the isobutylene isoprene elastomer.
As the name implies, butyl is comprised of isobutylene with a small amount of isoprene. It is known for its excellent resistance to water, steam, alkalis, and oxygenated solvents. Another outstanding characteristic is low gas permeation. Butyl is capable of providing high energy absorption (dampening) and good hot tear strength. Good resistances to heat, abrasion, oxygen, ozone."

http://www.plusind.com/Butyl.html
http://www.chemtron.ca/tape404_right.html
http://www.plustape.com/BK/index.htm

As you found out Suz, Putty Tape and Butyl Tape are two entirely different products. I believe Putty Tape will eventually harden up much like Plumbers putty. I am not sure what our 77 Boler had on the windows when I replaced them but it was gray and hard a rock, came off in chunks.

Products made for the automotive and aviation industries are superb but can be very expensive and not easily available to the average public.
As herb says some of the products in the 3M product lines for automotive work is really good. I recall one called "3M Drip Seal" that was great to use when I worked in a body shop.

[Brian B-P]

...Maybe this Butyl rubber stuff returns to its original shape after it is compressed?

The "butyl" putty (normally grey) is somewhat elastic, so it will to some extent regain its shape when compressed and released. That seems like a good characteristic to me, which is why I have used it rather than the traditional putty. Both come as strips on a paper backing, both are referred to as "tape", but neither is what the rest of the world commonly calls "tape".

Since this material clearly does not meet the which Con provided, and is not "rubbery", I assume that it is some putty material with a small butyl component.

[mitch]

I thought I was confused before.....

I've just read all the related links....

Unlike some of the other fiberglass trailers, ours does not have the "rat fur" or carpeting that others have on the inside of our walls...we have a composite wall with wood panelling. So we stuck to the method previously used...riveting the rail to the outside of the trailer. ( the rivet size that we used was aluminum 1/8" 3mm by 1/2" 12mm )

The putty tape we bought is 1/8" x 3/4" x 30 made by chemtron it is grey in color. Thanks Con for your links....definitelty a rubber sealant. Still think it was the right choice.

Still not sure about securing the bottom awning brackets though............

Thanks all ! Mitch

[mitch]

Butyl tape is the worst abomination from the 70's and should no longer be used. What happens is you put butyl tape under something, then rivet it on. Years go by and regular use causes the butyl to get squeezed out from between but the rivets don't tighten up. Then what you have is additional space that water gets into.

My first mission in restoring a trailer is to remove everything that has butyl tape under it and clean it off entirely. To seal stuff correctly, use modern technology. I prefer to use automotive seam sealer. It's meant for exterior use, doesn't shrink over time, stays flexible, paintable, and is also meant for use in a vibration environment (as opposed to household caulking junk like Mono, etc). Silicon is almost never the right goop for the job.

Also, don't just goop the caulking on. Mask all around where you're going to spooge the stuff, then affix the item in question, and peel the tape off leaving a nice clean line where the sealant ends.

Hey Herb P. ! Went straight to Napa CMax and got the automotive sealer. Thanks for the tip !! So we're gonna keep the awning rail with the butyl tape because quite frankly it seems to be holding just fine. Can we use the automotive sealer around the edge too though ??
We are thinking of doing the windows with the sealant as you recommended....So I understand about masking all around the edges but wonder about how much is needed to seal the window ? What is the consistency of the sealant ?? Is it runny or more like a putty substance ?? Should we put in on the window edges then mount the window and seal around it ?? How does it come off if you make a boo boo ? We really want to get this right the first time !!! Anything else we need to know about this stuff ?? thanks in advance for any advice Mitch and Brian

[Herb P]

Hey Herb P. ! Went straight to Napa CMax and got the automotive sealer. Thanks for the tip !! So we're gonna keep the awning rail with the butyl tape because quite frankly it seems to be holding just fine. Can we use the automotive sealer around the edge too though ??

We are thinking of doing the windows with the sealant as you recommended....So I understand about masking all around the edges but wonder about how much is needed to seal the window ? What is the consistency of the sealant ?? Is it runny or more like a putty substance ?? Should we put in on the window edges then mount the window and seal around it ?? How does it come off if you make a boo boo ? We really want to get this right the first time !!! Anything else we need to know about this stuff ??

I would probably not use seam sealer around the edge of the awning rail because as the awning rail is used, it will cause more of the butyl tape to ooze out from under the rail and thus push the seam sealer out with it and probably break the seal... That Butyl tape won't stay put and in a couple of years, it will probably be bulged out again...

I put a decent bead along the inside of the windows. On my 17, there is a small recessed area on the window frame where you are meant to put the grey putty, I oozed about a 1/4" thick (or more) all around the window in this groove. Mask the windows first so you'll know exactly how they go back in... If the window opens, you can reach in from outside to line up a couple of the screws (assuming the inner frame stayed put which they wanted to do on my 17 which made the job much easier). Then as you tighten screws, the sealant will ooze out from around the edge onto the masking tape. The inner frame is very thin so I recommend just snugging up the screws as you work your way around and then on your second way around tighten them up more... You might even want to work on opposing screws slowly working your way around... If you bend the inner frame, the window won't suck up against the fiberglass as much... This last part is important.. I definitely recommend a good cordless screwdriver or electric drill with a torque adjustment... Doing it by hand is going to be miserable. You'll also want to work sort of fast because the sealant that goops out along the edges is going to skin over... When I did mine, I had my 5 year old inside with the cordless screwdriver. He started the corner screws while I positioned/held the window on the outside. Then he put the rest of the screws in the holes as I came inside and started tightening them...

I use Nitrile gloves to squeegee the goop from around the windows and frequently dab my fingers on a rag to prevent any significant amount of goop from building up under my finger as I'm moving... The more goop under your finger, the further it spreads... You can use laquer thinner to clean up any mistakes or wipe up any that got on the frame or what have you...

Once you're done, look at the seal all the way around the window and make sure it's evenly 'oozed' out. Any parts that have a larger gap, might not have oozed and probably indicate a bent inner frame... You should probably inject some sealant into those areas and wipe them clean as well. Then you can remove the masking tape.

If it's a hot sunny day, the sealant will skin over faster.

Hope that helps.

[mitch]

Hey Herb ! thanks for the detailed response. I'll be honest , I thought that you might think it would be a bad idea to put the seam sealer around the awning rail and that leaving the butyl up wouldn't be so smart...We just didn't want to take it down because it was one of our first jobs...it took all day and we were so pleased with our rivet job !!!! Whine , whine !

We've been hard at work , like you, working every weekend on our trailer and quite frankly it's been a bit of a nightmare !!! Got our automotive sealant out and in the gun and NOTHING...Sometimes I feel like were in a Farside cartoon....!!! The stuff would not budge !!! hard as a rock ... Gotta go back and get some more

So, we moved onto other jobs that needed to be done...Like the dewinterizing....We attached the city water and got to it and....flooded the cutlery drawer immediately...So we replaced the "pipes" under the sink that day. We just finished fiberglassing and sanded yesterday. Looked all over the city for Interlux paint ( which was recommended by other members) Cant get it here in Calgary. I'm sure the lack of bodies of water is the reason. Ended up getting some marine paint and primer at General Paint. They carry a brand and so does Rona. Anyway , I hope that goes better...If you hear of a large fire in the N.E. part of the city this weekend it could be us torching our beloved trailer !!!

Thanks again for your advice. We will keep you posted with our adventure ! Cheers Mitch