Caulking and Sealants (silicone, parbond, vulkem & more)

[campw/4sons]

Thanks, Dave! Sometimes I forget that Search function....???

[ALANSD]

that answers my question too as I am going to remove the crappy silicone and redo it. Before that I will be using the aircraft stripper anyway, so it may make the silicon removal easier...

[2airishuman]

3m makes a good product that will also remove the siloxaine residues.....

3m general purpose adhesive remover.....

http://www3.3m.com/catalog/us/en001/...er/output_html

i've used it several times and it is very effective.....
but wear gloves and ventilate, ventilate ventilate.

cheers
2air'

[Globie64]

I've used Lexol on my house, sealing between redwood siding and aluminum window frames.

Okay, I've been using a really intense 3M product to remove all my Silicone caulk, 3M Marine silicone, clear, and I'm amazed how difficult it is to get the stuff off the aluminum. I'm sure it's better in the long run to replace it with Sikaflex or something, but if it sticks so well, I can't help but wonder if it would eventually fail.

Sigh.

Peter

[rmpray]

Interesting to see how applications change since the first post in this thread. I've used GE Silicone II Aluminum on aluminum boats with good adheasion and performance. Not for airplanes...true... but not going to eat away the skin. I expect my old rig will have to be a test platform as I've been sealing the roof seams with it. We will see. If the walls fall off I'll let ya know

[Jacob D.]

I bought a tube of that stuff - GE's page here - but haven't tried it yet, I've been using Vulkem so far. Vulkem is such a pain to apply though.

I'll report back if I get around to trying the GE product. I appreciate that "silicone = bad" was an excellent rule of thumb for decades, but those science people at GE are probably pretty smart & I'm open to the idea that something new could work better. Or not work better! I'm all about the empirical testing, but I haven't read about anyone using this specific product and either having good or bad results.

I may try first in some places where there was (junky) silicone sealing before, and see if the GE stuff sticks better than Vulkem. Getting the clear silicone out is not fun.

[lewster]

on this one! The Airstream factory (and yours truly) use Sikaflex 221 polyurethane for large work and Acryl-R for the small stuff. With a little practice, you can get really, really good with the Acryl-R and you won't even need to use tape!

The polyurethanes are moisture cure, so they go off quicker in humid weather. A little hint here....use a fine mist from a spray bottle to really kick the stuff......just don't tell anyone.....or I'll have to kill ya'

[Cat]

Re Sealant:
I still like the ALCOA (liquid aluminum); but Vulkem is so much like it. I personally like a dental 'pick' (you can buy tiny ones in the dental section of drug stores now---but getting a long-handled steel one from a dental hygenist (who are getting rid of them now to make way for disposable ones) & will give you one with very little coaxing.
This tool is used to pick out the old stuff you want to get rid of (yep! for cosmetic reasons)---for that person before you who HAD NO PRIDE!

Re Leaks:
When I bought "Bear"...there was a leak ON the bed (back bedroom). The seller never told me about it...and hid it well with comfortor etc.
Of course it didn't take long for me to find it (AFTER I BOUGHT IT ofcourse)...
the reason (because 'transmittal' always is a consideration). I got very VERY lucky! The leak was directly above the wet place on the bed.
The cause?
Some IDIOT didn't put the window back correctly after 'using it' for a fire escape...and as soon as that spot (where the fusalage seam is)..was sealed with Vulchem...the leak went AWAY.

YEY

[Devoman]

What about preping the area.What I mean is do you strip the old out and replace with the new?Can you take it all out.It seems some would stay in there.Some of the sealant above the door is cracking or seperating.I am guessing the sun finally got to it.I want to seal it with new sealant.Should I just dig out as much as I can.Then clean the area up and then seal it?
I have some sikaflex I have not opened yet but should vulkum be used instead?I see that the thread talks about all the sealers but I have not found an area where it tells what the whole process is and what to use when cleaning the area.
Needin some advise on it.Thanks everyone.

[LI Pets]

I use a new razor blade being careful not to scratch work into the seam, then use anything to pickup the little pieces.

clean with any solvent, acetone is good.

I then use masking tape on both sides of the seam, put on a plastic glove and push the sealer into the seam, smooth it out remove the tape.

When you remove the tape don't pull it away straight up, pull it on a sharp angle into the seam to get a nice edge.

[Jim & Susan]

Does anybody know the proper "cure" time for Parrbond? It's not listed on the tube and the only way to get the information sheets is by email from the manufacturer's website (that I can Find, anyway).

Thanks guys.

Jim

[Jim & Susan]

Well, I got the answer in less than an hour by emailing H.B. Fuller company customer service (the maker of the product). THAT is what I call customer service. Answer is 24 to 72 hours at 72 degrees with 50% humidity, depending on size of bead, in case anybody needs this in the future. There were data sheets available at the RV dealership where I bought this stuff.

Jim

[BB 55 Bubble]

I have looked into the mouth of madness.....its name is sealant!
Today I called the people who make Vulkem, I wanted to know just witch product I should use on the old trailer. The best Vulkem product is their 116 for the multi-purpose application on an Airstream Trailer. But wait there is more. I called several different manufactures, building supply Co., Trailer manufactures, and the occasional RV repair center. I learned on interesting thing. It would appear that the best product to use is a Butyl. I had mentioned to one tech that I had some sort of sealant on the trailer that I found to be still pliable after 50+ years. He said it was a Butyl sealant. I should use this type of sealant, specifically a synthetic one called TremPro JS-773. It was the major consensus that this is the way to go.
TREMCO web site is Division Home Page - Tremco Sealant/Weatherproofing Division.
From the website of TREMCO JS-773 is a ;
"High solids, non-skinning, non-drying, synthetic, butyl elastomer sealant. Designed for in-plant applications on joint seams in roll formed standing seam roof and wall panels, JS-773 is also ideal for buttering or bedding non-porous members that are squeezed together by fastening.
JS-773 can be used to separate dissimilar metals to prevent galvanic action.
JS-773 exhibits excellent adhesion to a variety of metals and metal finishes including hot-dip galvanized steel, Galvalume®, Kynar 500®, stainless steel, polyvinylidene fluoride (PVDF), aluminum, and fiberglass. JS-773 offers outstanding adhesion to oily metal surfaces."
I have also been informed that the best solvent to use is a product named Xylene.
So.... any thoughts?
BB 55 Bubble

[Devoman]

I used it to seal the fantastic fan when I installed it.It is really sticky and soft and comes in a roll about 1 and a half inches wide and several yards long.I still have some and will use it when I install another fan.That stuff is great.

[BB 55 Bubble]

This stuff comes in a tube that you can place in a caulking gun.

[LI Pets]

It's really funny it depends who you speak to in support, they told me Temco# 635 was the one to use

[Jim & Susan]

Tremco 635 is what I'm using (primarily using). I've also used Sikaflex 221 and Parrbond. The Tremco 635 is basically what the old Vilkem used to be. You can buy it here: Vintage Trailer Supply - Vintage travel trailer parts and supplies!

Vintage Trailer Supply is owned by soem really nice folks. I have and will do business with them again.

I'm using the Tremco (Vulkem) in areas where Vulkem was originally used on the camper. There are a couple of reasons for that. First and formost, most of the Vulkem that was orignally on the trailer is still there and in good shape. Where I'm having problems with the Vulkem is in areas where it was not applied properly at the factory, or in areas where leaks occured for other reasons and weakened the Vulkem or material the Vulkem was applied to. A secondary reason for staying with this product is that, no matter how much work you put into it, you can't get all of the old stuff off. I figure the few bits that remain won't interfere with the properties of the new.

I'm using Sikaflex (for the most part) in areas that didn't have any sealant on them in the first place. The rivets on the the inside of shell (the tail that sticks in thru the outer skin). I've forund several leaking (probably from day one, based on the stain patterns I've seen).

Last, I'm using Parrbond in areas that need need small, hidden seams sealed that I can later get to if need be (like where the belly pan attaches to the side of the camper).

Anyway, that's how I'm doing it.

Jim

[wahoonc]

Originally Posted by BB 55 Bubble

I have looked into the mouth of madness.....its name is sealant!
Today I called the people who make Vulkem, I wanted to know just witch product I should use on the old trailer. The best Vulkem product is their 116 for the multi-purpose application on an Airstream Trailer. But wait there is more. I called several different manufactures, building supply Co., Trailer manufactures, and the occasional RV repair center. I learned on interesting thing. It would appear that the best product to use is a Butyl. I had mentioned to one tech that I had some sort of sealant on the trailer that I found to be still pliable after 50+ years. He said it was a Butyl sealant. I should use this type of sealant, specifically a synthetic one called TremPro JS-773. It was the major consensus that this is the way to go.
TREMCO web site is Division Home Page - Tremco Sealant/Weatherproofing Division.
From the website of TREMCO JS-773 is a ;
"High solids, non-skinning, non-drying, synthetic, butyl elastomer sealant. Designed for in-plant applications on joint seams in roll formed standing seam roof and wall panels, JS-773 is also ideal for buttering or bedding non-porous members that are squeezed together by fastening.
JS-773 can be used to separate dissimilar metals to prevent galvanic action.
JS-773 exhibits excellent adhesion to a variety of metals and metal finishes including hot-dip galvanized steel, Galvalume®, Kynar 500®, stainless steel, polyvinylidene fluoride (PVDF), aluminum, and fiberglass. JS-773 offers outstanding adhesion to oily metal surfaces."
I have also been informed that the best solvent to use is a product named Xylene.
So.... any thoughts?
BB 55 Bubble

BB,
I work with metals and sealants for a living (architectural metals/metal roofing) the butyl caulk is designed for use IN the seams where sunlight cannot get to it. It IS NOT UV stable. Our general rule is if it is not exposed use butyl if it is exposed use polyurethane. They are semi compatible. We use several different brands of sealants depending on the metal manufacturer's specifications. My personal preference is the Tremco/Vulkem or the Sikaflex lines. Airstream used to use Vulkem and Parabond, now they use Sikaflex and Acryl-R. If the factory uses it I would use it. If you are using Xylene as a solvent make sure you read and follow the warning labels and the MSDS, it can be nasty stuff. For most clean up on Vulkem mineral spirits works fine.

Aaron

[Jim & Susan]

So here’s an exterior sealant question for all of you. I haven’t done much exterior sealing so far. Most all of the exterior sealing has been done in hidden areas (like behind trim, under the camper and so forth).

I tried my hand at sealing around the rear window a couple of days ago and I’m not really happy with how it turned out. I’ve included a few pics to explain my confusion.

The first picture shows where we found what is (I hope) the last leak in the rear of the trailer, between the window and the hatch. There are two bulges in the skin along that rivet line (not a great picture). In order to close the bulge, I taped it off and applied a thin bead of Sikaflex 221 gray, then smoothed it over with my finger (real hi-tech, eh?). Let it cure for a couple of days and removed the tape (pictures 2 & 3).

Here’s the question. Did everybody else have to make such a large or wide strip of sealant to close this type of seam? I’m not crazy about how this looks and am kinda looking for a way to make the seal smaller, or narrower. Any ideas out there?

As always, thanks for the input guys & gals.

Jim

[wahoonc]

Jim,
Personally I don't think it looks bad at all...for seams I would try the Acryl-R from Airstream, I used to recommend the Parbond, but the last round of stuff I did with it looks like crap and is going to get dug out and redone with Arcryl-R.

Aaron