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Is Flex Paste Bull or No Bull?

Posted at 6:28 PM, Oct 02, 2020
and last updated 2020-10-02 21:28:32-04

Throughout the years, I've enjoyed watching the commercials for Flex Seal Family of Products. I've tested Flex Tape and Flex Glue already, and they were both NO BULL! So, I'm testing out their latest product, Flex Paste, to see if third time's a charm!

Flex Paste is a thick, rubberized paste that is supposed to instantly fill gaps and holes. It's also supposed to cling to the surface, and once dry, it should be a flexible, strong, rubberized and watertight coating that seals out air, water and moisture. Click here to watch the informative and entertaining commercial.

The Flex Seal team actually sent me the product, Flex Paste, to test, and they also provided a couple materials.

Before getting started and after reading the directions, it's safety first! Be sure to wear protective eye wear, gloves and clothing you don't mind ruining if Flex Paste gets on it.

We worked outside, as the instructions state your workspace should be in a well-ventilated area. We set up a table and covered it with tarp-like material in case we dropped any of the Flex Paste.

Then, we made sure the surfaces of all the items were free of grease, oil and dirt.

The first test was one of the provided materials, a woodblock that had two cuts.

So, we opened our one-pound tub, took out the silica packet and then removed the foil. DO NOT throw away the foil or the silica packet. You'll need them between each use, and to store and preserve Flex Paste.

We used the putty knife to scoop the Flex Paste and spread it across to not only cover the surface, but also fill the gaps. It immediately went all the way through. We'll come back to this.

Then, as instructed, we replaced the foil back onto the Flex Paste, pressing it against the material inside, until we brought over our next test subject.

The other item we were sent was part of a PVC pipe. It had two holes in it. One was completely covered with Flex Paste that had cured and dried, and the other hole was exposed for us to attempt to cover.

This time, I used painters tape to try and match the square-like shape of the hole that was already covered. In one swoop, the hole disappeared. More on this later.

Another claim is that Flex Paste is supposed to work on multiple surfaces, including natural stone. I ended up using the paste to combine two decorative pieces of stone. It was like a Flex Paste sandwich! Then, I set it aside.

For the final test, I wanted to do something similar to what happens in the Flex Paste commercial. Phil Swift takes a chainsaw and cuts a water fountain contraption. As water comes gushing out of the half wine barrel he just cut, he stops the flow with one swipe of Flex Paste. Take a look!

For our smaller version of this test, we drilled two half-inch holes in this thick plastic container. We filled it with water. Since Flex Paste claims to dry underwater, we applied it from the inside on one hole and from the outside for the other. In just one swipe each, there were no more leaks!

Let's fast forward to 24-to-48 hours later. We checked on all four tests. They had all dried and cured completely.

The wood was solid, We removed the painter's tape from the PVC pipe, and our shape was close to square. A box cutter made the lines extra clean. The two natural pieces of stone were secured. And the container was still filled to the same level with water. When I dumped the water out, I checked the hole that was covered from the inside. Flex Paste definitely lives up to the claim of drying and curing underwater.

So, where does Flex Paste rank on our Bull or No Bull Meter? I'm going with... NO BULL!

You can purchase this product on their official website or even on Amazon. Prices start at $12.99 and will vary depending on the size you order.

There are a few claims we have not tested yet. It's supposed to be UV and mildew resistant. The commercial shows how it can be used indoors, outdoors to make repairs or even crafts for projects.

Also, it's not intended for high water pressure, like fixing a garden hose.

According to the website, Flex Paste, "will work on wood, glass, tile, concrete, aluminum, metal, brick, stucco, masonry, copper, fabric, fiberglass, ceramic, porcelain, natural stones, roofing, PVC, EIFS, EPDM, CSPE, Hypalon polyurethanes and so much more."

Here's another reminder. When using the product, it's important to cover Flex Paste with foil to keep it from drying out in between scoops. When you're done with the product, place the foil and silica packet back on top, close the lid and store in a humidity-controlled environment.

There are even more steps to preserve Flex Paste, including removing the skin and more. Click here to read more about the directions, description, clean-up process and more. Here's a video showing how to use the product, and here's another video showing how to apply the product.


What do you want me to try before you buy? Email me!