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Sikaflex 221 bonds well to a wide variety of substrates and is suitable for making permanent, high adhesive strength elastic seals. Use 221 on substrate materials wood, metals, metal primers and paint coatings (2c or 2 part systems), ceramic materials and plastics.
$9.90
$9.90
$23.06
$2,945.02
$9.94
$9.94
$9.90
$9.90
$313.34
$296.78
$2,945.02
$9.90
$9.90
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Sikaflex-221 is a high-quality multi purpose non-sagging 1-component polyurethane sealant that cures on exposure to atmospheric humidity to form a durable elastomer.
Key Features
1-Component Formulation (1C)
Elastic
Low Odor
Resistant to aging and weathering exposure
Non-corrosive
Can be painted over
Can be sanded
Bonds well to a wide variety of substrates
NSF-approved for incidental food contact and potable water.
Sealant type: Polyurethane
Temperature: -40 to 195 F
Time until tack free: 60 min
Full cure time: 60 min to 10 days
Tensile Strength: 260
Hardness: Shore A 40-45
Specific Gravity: 1.27
Elongation: 500%
BRAND:
Sika
Material:
Polyurethane
Number Of Parts:
One Part
Type:
Adhesive
Usage:
Sealing
Questions & Answers about Sikaflex 221 One-Component Adhesive Sealant:
2012-10-02A shopper asked: How do you remove 221 sikaflex ?
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2012-10-02RICHARD HAAS: Did not try.
used it to reattach convertible rear window (plastic window) Masked off area I didn't want to get sealant on.
2012-10-02MARK RATLIFF: I am using Sikaflex on my Airstream trailer. I have not had to remove Sikaflex yet. I have had to remove silicone caulk from the trailer using plastic and wood scrapers and RemovALL. The RemovALL seemed to help a little, but it was mostly the manual effort with the scrapers that did the work.
You can find some additional advice on removing Vulkem (similar to Sikaflex I understand) here on the Airstream Forums (airforums dot com)
2012-10-02DONALD WOODWARD: Depends what it is on. If it is on fiberglass or a plastic surface, try acetone. If on other surfaces, try xylol (aka xylene or "goof off").
Careful with these, they may eat the surface, so try on small part of it first.
2012-10-11JIM ZYNSKY: I do not know once it has cured, you will have to contact mfg, sorry
2012-09-16ROB SPARKS asked: will this product stick to HDPE?
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2012-09-17PATRICK SMILEY: We use it for aluminum to fiberglass (FRP) panels. The only sure way to check if it will work in your application is to buy a cartridge and try it on a sample. It is a very good adhesive.
2012-09-17PAUL CAUGHEY: As long as you ruff it up yhere is no problum
2012-09-19LES PROCK: Hello
I bought this to reseal a cable entry point on my Airstream. I haven't used it yet, and cannot say if it will stick to HDPE.
2012-09-21JOE JUNGCARDON: I purchased the sika 221 at the request of the customer I had to seal around through bolts on an RV roof. I downloaded the specs from sika in order to do the job, but they left with the customer. I would suggest checking the sika web site, and I think they have a tech support number. Sorry I can't help further, good luck.
2012-09-14VERNE HALIKAS asked: What colour is Coping Stone ?
2012-09-05A shopper asked: will this product stick to silicone sealents?
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2012-09-05CHRISTOPHER ABRAHAM: I think it will, but can't say for sure. This is a good product and I've been very satisfied with it.
2012-09-05DANIEL O`CONNORS: I did that. I put a cheaper Silicon in a gap between to oak boards and filled the rest with 221 and sanded it. I works perfect. The gap is a 1/4 inch.
daniel
2012-08-25CHARLES REED asked: Does this material meet any Military, Navy, or industry specifications?
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2012-09-06THOMAS SAUNDERS: I have used Sikaflex 221 as the roof sealant for my RV. It remains flexible, is weathertight, and serves its purpose well. However, I personally do not know if there are any Mil-Spec compliance certifications for Sikaflex 221. The proper place to get the answer to that question would be the manufacturer. Have you tried doing a google search for "Sikaflex" and then sending an email to them about your question?
2012-09-06JOHN RHETTS: contact the company.
2012-08-23FREDERIC ZONSIUS asked: Can it be applied to wet surfaces?
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2012-08-24MARTIN FISHMAN: application procedure require a dry surface
2012-08-24JAMES KEEFER: -WE DO NOT USE THIS PRODUCT IN MARINE APPLICATIONS BUT RATHER FOR ITS ADHESIVE AND SEALANT PROPERTIES THAT ARE REQUIRED AT THE SCREENS AND SEALS ON VACUUM DRYERS USED IN THE PROCESSING / TANNING OF COWHIDES.
-IT IS OUR EXPERIENCE THAT IN THIS APPLICATION ANY MOISTURE ON THE SURFACE OF THE JOINT WHERE THE PRODUCT IS APPLIED COMPROMISES THE SEALING / ADHESIVE QUALITY BUT BEAR IN MIND THAT IN OUR EQUIPMENT IT IS EXPOSED TO RATHER EXTREME VACUUM ALONG THE SEAL SURFACES. THIS MAY NOT BE AN ISSUE FOR YOU.
-SORRY I COULDN'T BE OF MORE HELP.
2012-08-24JOSHUA SWAN: My intuitive response is to advise against it. Unlike some boat life products which advertise themselves as curing better with moisture, I don't know if the same is true for sikaflex 221, especially given how quickly it cures (1-2hrs) as opposed to boatlife (3-7 days). That said, it'd be worth contacting sikaflex tech support for a more informed answer. Regardless, having the material dry is important for any other steps involved in your project, like finishing. If this is an emergency and/or stop gap measure to get you to the end of the season that would be different. In any case, good luck with it.
Sincerely,
Josh
2012-08-25DONALD WOODWARD: No. It will peel from a wet surface.
It CAN get damp after it is applied and will set up okay, but must be dry first.
2012-08-27JIM ZYNSKY: preference would be not. If no choice then it really depends on material you are going on. A non porous slippery material to begin with the answer is no, if the material you are going on is porous and the weather condition is for drying trend rather then continued wet I would apply - it should work
Jim
2012-06-11JOSE MADRIZ asked: My client wants me to put a bed of a Sikaflex product on the ground so that his planter pots can sit on it. The planter pot has a 2" hole at the base and the ground has an 8" dry well where the water drains. I'm getting seepage under the planter pot which is why I need to seal it. I need to use a Sikaflex product but I am not sure which one to use? Please let me know.
Jose Madriz
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2012-06-13MARTIN KLUKSDAL: Jose,
We used this sealant as it was specified by an engineer for a cooling tower application. I think you could use any outdoor silicone based sealant or caulk for what you are doing. If Sikaflex is expensive as I recall, you could buy something cheaper.
2012-05-22A shopper asked: I want to fill a vertical seam ( butt joint 1/4" wide ) between two 1x10 wood planks on the outside of a house. Which product do you recommend - 221, 227?
2012-05-21FIRST NAME LAST NAME asked: Would this be applicable to sealing an aluminim hull seam on a small fishing boat?
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2012-05-21JAMES MARTIN: I should imagine so. We used this to seal an aluminum production tool designed for high extremes of temperature and pressure. It has worked extremely well. Follow the operating instructions exactly and give plenty of time for surface prep and curing.
Hope this helps.
2012-05-21THOMAS SAUNDERS: I'm unsure, it might be worth checking with the manufacturer (Sikaflex). I used it to seal seams on my motorhome. I suppose if your aluminum hull seams are above the waterline it might be very good. The material stays flexible, is very sticky, tolerates sun very well, and is easy to apply. Hope this helps.
2012-05-21MARC ORMAN: This stuff sticks to everything.
Wear your gloves.
2012-05-22NATHANIEL HOLT: Yes, very much so. I have used this product for a various repairs over the years from aluminum boats to semi trailer roof repair, remains pliable and is also paintable. I also work for a world class, class 8 truck manufacturer where we use this product to seal all joints and seams during assembly. Hope this helps GREAT product!!!!
2012-05-23DANIEL DIMARTINO: I used it to join body seams on a car but I think this is the best long term sealant you can buy. Originally made for the auto indusrty I think it will work fine on a boat.
2012-05-25RHONDA PIRTLE: We used Sikaflex exclusively in the high dollar rv coach industry manufacturing, putting in windows , both side and front, slide-out aluminium flashing and anything else we needed to seal from moisture and rain. This stuff really works! It is best if you use a primer first to clean the surface but acetone will work just fine. You need a clean, dry surface to lay it down on so it will stick well. Have to warn you, it doesn't come off your hands or clothing so dress accordingly and be careful not to get it on areas you don't want it on. If you do, get it off quick with acetone or something like Klean Strip adhesive remover. By the way there are different application sealants by Sikaflex so if you need white instead of black it is available, so look it up on the internet and do some research for your application.
Hope this was helpful and good luck!
2012-05-07A shopper asked: used on fiberglass roofs?
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2012-05-07WALLACE MCVEY: I used it to caulk the seam between the coping edge of a swimming pool and the surrounding concrete deck. It has been in place for just over 2 years now. It has stayed flexible, has not shrunk, and appears to be holding up to the elements. I live in the San Francisco Bay Area, so we don't encounter freezing conditions.
2012-05-08WILLIAM GRIFFIN: Yes, it will hold on fiberglass. It is a flexible bond.
2012-05-08TODD FREEDMAN: I used it on a metal roof and it worked well.
Comments about Sikaflex 221 One-Component Adhesive Sealant:
Great waterproofing product. Excellent sales experience.
Was this a gift?:
No
1/3/2013
5.0
Great
By Jsslng
from Wilmington, NC
About Me Professional
Pros
Easy to Use
Protects Well
Weather Proof
Cons
Messy
Best Uses
Comments about Sikaflex 221 One-Component Adhesive Sealant:
I actually used this product to seal the sewed seams on my wetsuit. It worked great. Used the left overs on some wooden framed windows on a 37 Elko, still water tight.
Was this a gift?:
No
11/7/2012
5.0
Great stuff to seal horse trailer roof.
By Maître
from Oxford, OH
Pros
Easy to Use
Protects Well
Visually Pleasing
Weather Proof
Cons
Best Uses
Outdoor
Quick Fix
Comments about Sikaflex 221 One-Component Adhesive Sealant:
Used it to seal the aluminum seals on the roof of a Sundowner Horse trailer. It worked great. Using a curved piece of metal to shape and grade the calk in places is a big help.
Was this a gift?:
No
9/11/2012
(1 of 1 customers found this review helpful)
4.0
Works as advertised
By Bob the handyman
from North Carolina
About Me Advanced
Pros
Weather Proof
Cons
Best Uses
Outdoor
Reseal Horse Trailer
Comments about Sikaflex 221 One-Component Adhesive Sealant:
Used to reseal an aluminum horse trailer and it worked well. Product was easy to use and dried flexible but firm. Time will tell how the product stands up over time but it has already served the purpose
Was this a gift?:
No
7/4/2010
4.0
Great Product
By Northstar
from Tunnel Hill Ga
About Me Beginner
Pros
Easy to Use
Protects Well
Visually Pleasing
Weather Proof
Cons
Messy
Best Uses
Outdoor
Quick Fix
Comments about Sikaflex 221 One-Component Adhesive Sealant:
*This product was used to fix rear glass window on convertible.
*Its Works!!!
*Messy, but easily clean up with acetone solvent
5/19/2010
(1 of 1 customers found this review helpful)
5.0
excellent adhesive caulk; sticks to all
By Jim Z
from Monroe, NC 28112
About Me Professional
Pros
Easy to Use
Excellent adhesion
Protects Well
Weather Proof
Cons
Cleanup immediately
Messy
Best Uses
Indoor
Outdoor
Quick Fix
Windows roofing
Comments about Sikaflex 221 One-Component Adhesive Sealant:
I use this product for a number of high end residential house construction projects. Bonding and waterproofing are its best qualities. It is a ureathane caulk so it is a little messy and any caulk that gets away needs to be cleaned/wiped up immediately to keep from getting onto everything. The product is better for cleanup and smoothing out then older formulas of Sikaflex caulk. Great product. I use a fair amount of it. Jim Zynsky Comfort Green Buildings Monroe, NC 28112
3/16/2010
(1 of 1 customers found this review helpful)
5.0
Stuff was good in 1987, still good now
By Leen
from Sacramento, CA
About Me Casual/ Recreational
Pros
Easy to Use
Protects Well
Visually Pleasing
Weather Proof
Cons
Best Uses
Comments about Sikaflex 221 One-Component Adhesive Sealant:
The instruction video that came with my 1987 convertible BMW showed SikaFlex 221 being used. Looked around online and found JD's website. It's easy to apply, it's easy to mold, and it will stay on for over 20 years like the previous application did. Good stuff, and easy to get at JD's.
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