You might have bought Flex Seal Tape for your project after seeing the infomercial that claims – Flex Seal Tape can stick to almost anything.
But does that mean it can stick to anything?
After trying the product myself and discussing the same with industry experts, I have found that Flex Tape is ineffective on surfaces made of certain materials and objects under high pressure and temperatures.
Test it on your material to see if Flex Tape is the right product for you. While it might stick to surfaces like those listed below, I don’t recommend relying on Flex Tape in those situations and areas.
This article will discuss in detail – when you should not use Flex Tape – while examining seven things the tape won’t stick to.
Surfaces Flex Seal Tape Don’t Work On?
Flex Tape is designed to work almost immediately, and it usually takes around 24 hours for the adhesive to be completely set.
Even though Flex Tape’s adhesive is strong, it, unfortunately, can’t stick to everything.
The pressure, temperature, and type of chemicals present all play a part in Flex Tape adhesion’s success (or lack thereof).
Here’s the list of things that I’ve found Flex Tape doesn’t adhere well…
1- Rubber Tires
Although Flex Seal’s rubber-like backing allows it to be flexible and sturdy, it is not as infomercials led us to believe.
According to the manufacturers, their Flex Tape product is recommended for normal hydrostatic pressure.
It’s not designed to withstand high pressures, such as pressurized pipes or engine machinery.
The raised ridges on the tires (of cars, motorcycles, or bikes) can make it tough for your Flex Seal Tape to adhere.
Also, the high pressure from being used on the road will stop Flex Seal Tape from sticking for a long, thereby not making the tires completely leakproof.
That said, Flex Seal Tape can be your temporary fix in case you need a quick band-aid solution for a small hole or crack in your tires.
2- Water-Repellent Surfaces
Flex Tape will not adhere properly to surfaces that repel water, generally hydrophobic surfaces made with water-repellent material.
When the adhesive on Flex Tape comes into contact with these types of surfaces, it has trouble bonding and creating an even layer.
To check if the surface you’re working with is hydrophobic, splash some water on it.
If the water droplets start beading up and rolling off, the surface is not ideal for Flex Tape.
3- Siliconized Surfaces
Flex Tape adhesive does not stick to siliconized surfaces as well.
Silicone is a material used to create a water-resistant seal. It’s generally a blend of rubber and plastic, which you’ll find in many different items like caulk, aquariums, lubricants, and kitchen utensils.
The problem with Flex Tape and silicone surfaces are that when the two come into contact, it creates an uneven surface, which makes it difficult for the adhesive on Flex Tape to bond evenly.
In the same way, Flex Seal Tape will not adhere to paint. If you need to seal a painted surface, I recommend using Flex Seal Spray instead.
4- Radiator Hoses
You may think Flex Tape would work perfectly on radiator hoses, but this is not true.
The Flex-Seal brand advises against using Flex Tape on these types of hoses and surfaces that are either too hot or too cold.
Radiator hoses connect your vehicle’s engine, radiator, and water pump to move cooling fluid around the engine. This process creates a lot of heat and pressure within the hose.
Even though Flex Tape might adhere to similar surfaces, it will not last for an extended period due to outside factors.
The high pressure from the mechanism will cause leaks, while constant exposure to heat will stop the Flex Tape from setting entirely.
5- Gas And Oil Tanks
Flex Tape is also known to adhere to metal gas or oil tanks temporarily. However, similar to hoses, it’s not the best idea.
The pressure and heat from these types of tanks will eventually cause Flex Tape to no longer stick. Not only that, but this could be a safety hazard as well.
If you try patching up a hole in your tank with Flex Tape, any gas or oil content can still leak through – because Flex Tape is strong enough to bond materials together but not prevent other elements from passing through.
6- Surfaces with Grease Oil or Chemicals
Flex Tape does not adhere well to greasy or oily surfaces. The tape is also not effective when used with harsh chemicals like acids, mineral spirits, and acetone.
If you want to use Flex Tape on a typically sticky surface that has somehow come into contact with chemicals, grease, or oil, it’s good to clean the surface first.
The easiest way to do this would be with soap and water, but it could vary depending on what exactly you are cleaning.
Once the surface is cleared of residue, your Flex Tape should stick as normal!
What Will Flex Seal Tape Stick To – Does it Work?
Flex Tape can be used for a variety of applications, both indoors and outdoors. Some common uses include:
- patching holes in walls or roofs
- sealing leaks in pipes or hoses
- repairing cracks or holes in boats, RV roofs, or pools
- temporarily patching holes in car tires
The good thing is that the Flex Tape sticks well and works on a large number of surfaces like steel, copper, aluminum, acrylic, glass, wood, stone, cement, ceramics, plastic, and fabric, to name a few.
In fact, Flex Seal Tape’s key selling point is that it works even underwater – a claim they advertise on their website.
If the material is compatible with the tape, it will stick no matter how wet; however, some surfaces (such as porous ones) may require a little heat for optimal bonding results.
For best results, use a hair dryer to heat the adhesive tape before attaching it to such surfaces. The tape should be set and adhered firmly in about 24 hours.
How to apply the tape?
Applying the Flex tape is straightforward:
- Clean the surface; you want to apply the tape. Ensure the surface is dry and free of dirt, grease, or oil.
- Cut the tape to the desired length and width using a sharp knife or a razor blade.
- Peel off the transparent backing from the tape.
- Apply the tape to the surface, and smooth out any bubbles.
- Press down on the tape to ensure it is firmly attached. And allow the tape to set for 24 hours before putting it to use.
You can use a hair dryer to speed up the bonding process. Just make sure not to overheat the tape.
Is Flex Tape waterproof?
Flex Tape holds stronger and longer than other tapes and is water-resistant.
Although the tape is waterproof and you can use Flex Tape to cover up leaks, take care when applying it to certain areas because high water pressure or incorrect application will diminish its effectiveness.
Flex Tape MAX is another upgraded version of Flex Tape that supposedly covers 400% more area.
If you require a more powerful waterproof material, it may work better for you.
A more dependable long-term option would be Flex Seal, a waterproof liquid sealant. Like Flex Tape, it will take 24 to 48 hours to completely bond or cure in this case.
Is Flex Tape Removable – How to Remove it From the Surface?
When Flex Seal Tape dries, it will stay in place for a long without any move. You would need an adhesive remover to get rid of the tape because its adhesive is very strong.
Flex Seal has their brand of adhesive remover (The Flex-Seal Adhesive Remover) – a specialized product designed to work with Flex Tape.
The remover comes in spray form for easy application and works on other tape types. So you can be sure it’ll do the job when it comes to removing the tape.
If you cannot find one on the market, worry not, as other brands can work.
The bottom line
Flex Tape is not a long-term solution but works best as a temporary or emergency fix.
Therefore, if Flex Tape is your only option, you should still plan to get the damages adequately repaired or replaced as soon as possible.
You only need to remember that it doesn’t work on all surfaces and has the right surface to adhere to.
If done correctly, Flex Tape should work great and save you a lot of money.
Jack Luis is a semi-retired painter who loved painting his clients’ ideas on their walls.
He had worked as a painter for more than a decade to serve the customers in areas such as Charleston, Mount Pleasant, Beaufort, Georgetown, SC (South Carolina). Today in his free time, he likes to read and write about the newer techniques that are being implemented in his profession. You may read more about him here or get in touch with him here.
Just in case you want to hire pro painters in your local area, you can click here. We can instantly send you free quotes from trusted painters based on your specific requirement.