Experience with Sikaflex 220+ as a sealant?

[Sevier]

Hi folks -

We used Sikaflex 220+ to seal over the gaskets on our windows, and, nowhere on the data sheet for the product, nor anywhere on any forum where I've seen others use it, nor during multiple conversations with Sika reps, was it ever mentioned that a primer needs to be applied first.

We were just now told this by a sika rep when we called with a followup question, after the fact. So, we sealed 22 windows wrong, and were told we have to clean it all off and do it all over again with the primer, for it to properly seal.

Does any one have any experience with Skiaflex 220+? Did you use a primer (they say SikaPrimer 207 or SikaPrimer 206 in conjunction with SikaActvator 100).

Thanks all.

[Plyshocky]

I have use this product once on a Job and did not use primer. No Issues. And I used Sikas Commercial Sealant for years. I'm a Paint contractor which will in time build my dream Skoolie. I just read the application sheet on this and your correct no mention of primer. My experience with this stuff it will stick like Mother to anything dry-clean and without silicone. If you did clean things up before application. You will be fine, not sure what the Rep. is talking about. I will tell you the Sikaflex Commercial Sealant you can get at Lowes/ HD & commercial building supply houses. Is Fantastic! From shingle to galvanized flashing, to wood window frames to Brick, to Concrete to Aluminum Frame to Concrete to concrete. ( this is what it was made for sealing tilt up sections of concrete walls.) It will stretch 200% of Dry width. And I have use to seal my work vans windshields with great results and performance. My opinion - If it leaks fix the spot, if doesn't don't worry and leave it alone.. Joe

[ol trunt]

I am a Sikaflex devotee. I have used it successfully for countless glass installations without a failure. I also used it to seal all the seams and rivets in my bus and after many years it is still behaving properly.

I generally test all products of this nature for their intended use before going hog wild. With this said, the only thing I've tested so far (with SF 220+) that failed was when I tried to use it to affix polycarbonate panels to primed steel surfaces. It stuck to the primed steel but let loose of the polycarbonate after a week or so. 3M double stick tape was the answer for that.

SF220+ is easy to clean up while fresh with mineral spirits and is paintable with anything once dried.
Jack

[Sevier]

Originally Posted by Plyshocky

I have use this product once on a Job and did not use primer. No Issues. And I used Sikas Commercial Sealant for years. I'm a Paint contractor which will in time build my dream Skoolie. I just read the application sheet on this and your correct no mention of primer. My experience with this stuff it will stick like Mother to anything dry-clean and without silicone. If you did clean things up before application. You will be fine, not sure what the Rep. is talking about. I will tell you the Sikaflex Commercial Sealant you can get at Lowes/ HD & commercial building supply houses. Is Fantastic! From shingle to galvanized flashing, to wood window frames to Brick, to Concrete to Aluminum Frame to Concrete to concrete. ( this is what it was made for sealing tilt up sections of concrete walls.) It will stretch 200% of Dry width. And I have use to seal my work vans windshields with great results and performance. My opinion - If it leaks fix the spot, if doesn't don't worry and leave it alone.. Joe

Thankyou Joe, this is so reassuring. We were also told by another rep, once he understood we didn’t use it to actually secure a window, just to seal over old leaky bus window gaskets, that it is probably fine, it will bind to the rubber fine. And then just after that, another rep said no way, it won’t bind to rubber and it was absolutely the wrong product to use. So maddening. I’d trust the opinion of Skoolie builders who’ve used it successfully over these guys.

In your experience, would Sikaflex 220+ bind to the rubber of the bus window gaskets? We made sure to give the bead of caulk good contact with the glass and metal on each side of the gasket.

Oh, and yes, we cleaned very thoroughly Not only had we already cleaned the windows when we removed them, but I washed all the gaskets again with sopay water, then a wipe down with mineral spirits.

[Sevier]

Originally Posted by ol trunt

I am a Sikaflex devotee. I have used it successfully for countless glass installations without a failure. I also used it to seal all the seams and rivets in my bus and after many years it is still behaving properly.

I generally test all products of this nature for their intended use before going hog wild. With this said, the only thing I've tested so far (with SF 220+) that failed was when I tried to use it to affix polycarbonate panels to primed steel surfaces. It stuck to the primed steel but let loose of the polycarbonate after a week or so. 3M double stick tape was the answer for that.

SF220+ is easy to clean up while fresh with mineral spirits and is paintable with anything once dried.
Jack

Thankyou Jack, and yes, I am remembering now, you are the one I saw reference Sika products often! I rust a Skoolie builder with experience over a Sika rep, especially given how many times they have contradicted eachother

Should have definitely tested before going hog wild, hopefully have learned our lesson. The waterproofing of this bus is probably the most stressful part of this, I am just so nervous we won’t have a safe healthy dry bus.

In your experience, do you think it will have decently bonded to the rubber window gaskets long term? We made sure we gave it a nice wide head, across the rubber, to bind to the glass pane and the metal trim on either edge of the gasket.

*I trust (not rust)

[Sevier]

Originally Posted by ol trunt

I am a Sikaflex devotee. I have used it successfully for countless glass installations without a failure. I also used it to seal all the seams and rivets in my bus and after many years it is still behaving properly.

I generally test all products of this nature for their intended use before going hog wild. With this said, the only thing I've tested so far (with SF 220+) that failed was when I tried to use it to affix polycarbonate panels to primed steel surfaces. It stuck to the primed steel but let loose of the polycarbonate after a week or so. 3M double stick tape was the answer for that.

SF220+ is easy to clean up while fresh with mineral spirits and is paintable with anything once dried.
Jack

Oh, and which Sika did you use to seal your seams and rivets? And did you sand down to bare metal first? Or just rough up and clean with mineral spirits?

I think I recall you mentioning 221 in past posts ...

[ol trunt]

I hope I've only touted Silka 220+ as it is all I've used for everything.

As to prep on seams and around rivets, as long as you get all the loose stuff off, wash with detergent, sand with 220 grit and rinse with lacquer thinner (not mineral spirits because it is oily) you'll be good to go. Clean up and smooth the top of the SF220+ with mineral spirts but don't soak it. Silka will stick well to rubber as long as it is clean and not badly oxidized.
Jack

[Sevier]

Originally Posted by ol trunt

I hope I've only touted Silka 220+ as it is all I've used for everything.

As to prep on seams and around rivets, as long as you get all the loose stuff off, wash with detergent, sand with 220 grit and rinse with lacquer thinner (not mineral spirits because it is oily) you'll be good to go. Clean up and smooth the top of the SF220+ with mineral spirts but don't soak it. Silka will stick well to rubber as long as it is clean and not badly oxidized.
Jack

Great, thankyou! We actually used soapy water and then mineral spirits to wipe the window gaskets before sealing How badly could that impede a bind? If it seems stuck on now, it will likely remain stuck on?

[Sevier]

Originally Posted by Plyshocky

I have use this product once on a Job and did not use primer. No Issues. And I used Sikas Commercial Sealant for years. I'm a Paint contractor which will in time build my dream Skoolie. I just read the application sheet on this and your correct no mention of primer. My experience with this stuff it will stick like Mother to anything dry-clean and without silicone. If you did clean things up before application. You will be fine, not sure what the Rep. is talking about. I will tell you the Sikaflex Commercial Sealant you can get at Lowes/ HD & commercial building supply houses. Is Fantastic! From shingle to galvanized flashing, to wood window frames to Brick, to Concrete to Aluminum Frame to Concrete to concrete. ( this is what it was made for sealing tilt up sections of concrete walls.) It will stretch 200% of Dry width. And I have use to seal my work vans windshields with great results and performance. My opinion - If it leaks fix the spot, if doesn't don't worry and leave it alone.. Joe

Originally Posted by ol trunt

I am a Sikaflex devotee. I have used it successfully for countless glass installations without a failure. I also used it to seal all the seams and rivets in my bus and after many years it is still behaving properly.

I generally test all products of this nature for their intended use before going hog wild. With this said, the only thing I've tested so far (with SF 220+) that failed was when I tried to use it to affix polycarbonate panels to primed steel surfaces. It stuck to the primed steel but let loose of the polycarbonate after a week or so. 3M double stick tape was the answer for that.

SF220+ is easy to clean up while fresh with mineral spirits and is paintable with anything once dried.
Jack

Hello Jack and Joe -

How would you two suggest waterproof sealing up rear windows and windshield? They have those huge wide thick rubber gaskets, not wedged between glass and metal trim, you know, and you can pull the one edge of the gasket away from the window glass, it doesn’t seem to be attached at the top edge.

We were going to clean in the little crevice best we could (with a non-mineral spirits thinner (thankyou for that note Jack!) on a rag slid long the crevice with a thin painters tool), and thenSikaFlex 220+.

Just so stressed bc a Sika rep said there are many different kinds of rubber, and gaskets, and caulk often doesn’t bind to it.