Bon Tool Anti-Crack Concrete Fibers

This Bon product is actually a bag of Owens Corning Anti-Crak HD (High Dispersion). According to the Owens Corning product sheet, "These fibres are designed to be used with normal concrete mixes at very low addition levels – typically 0.6kg/m3 (1lb/yd3) of concrete. Added directly to the mixer or ready mix truck, they disperse instantly within the concrete. This complete uniform dispersion ensures a three dimensional reinforcement throughout the matrix and thus an effective suppression of cracking during the plastic shrinkage period. The large number of filaments gives a very small distance between fibres whilst the high aspect ratio gives maximum effect in the setting period." Technical details: Product form: Monofilament as a result of dispersal of fibres bundles on contact with moisture Numbers of fibres: >100 million/lb Aspect Ratio: 857:1 Specific surface area: 518 ft2/lb Typical addition rate: 1 lb/yd3 of concrete

Putting in a new concrete floor in my garage...price difference at the store for bag of concrete with and without fiberglass reinforcement is about $2 each. A bag of these concrete fibers costs $15 or so and contains enough for sixty 60 pound bags of concrete. That's a huge savings and the fibers are way easier to deal with than mesh or rebar (neither is "required" for unheated garage floors). I used a scale to measure out 1/3 oz of fibers for each bag of concrete...that means each 1lb bag of fibers reinforced 48 bags of concrete. Did 12 at a time, put them in small plastic cups and just grabbed one cup at a time as each bag got mixed. Added water to my running cement mixer, added the fibers, then added the concrete. The fibers mixed evenly and don't show in the finished product.

It is a bag of fiber, and it mixes into the concrete fine. However, the most important aspect of the fiber, it's alkali resistance, can't be determined by inspection so I was not very happy to see that the product is no longer labeled as Corning Anti CRAK fibers. Since the long term performance of the fiber depends on the fiber composition, I would not use this for anything other than plastic shrinkage control since the provenance of the fiber is unknown.

This product significantly reduced plastic cracking on stucco base coat. It is difficult to get it mixed properly. I had the best luck pre-mixing it in a jug of water. It expands significantly when added to water. I measured it using a gram scale for individual bags of cement - 8.4gm per 80lb bag.

It’s best to mix the cement to your liked consistency then mix the fibers in, it added to dry cement mix it’s difficult to mix by hand. I tried wetting the fibers first then mix and this caused the fibers to clump up together. Best results for HAND mixed is to mix the cement and mortar first with needed water then add fibers, mix, add more fibers and mix more. Best consistency achieved this way for mixing manually.

I used 3 pounds of fiber in this concrete table and no cracks. It's been 5 years and I can't even see any small cracks.

I have mixed and poured 8 cubic yards of concrete with these glass fibers (flat patio) and have no cracks so far. The fibers are easy to work with. I mix them with water in the mixer first. I like these compared to nylon fiber because they do not produce much fuzz on the surface. The slab I have poured is 2.5 inches thick. I have 3/8 rebar in it, but the fiber is an inexpensive way to add strength.

I've heard a lb. of fiber per yard but doesn't seem like much if these bags truly have 1 lb. of fiber in them. Mixed a yard by hand for small pour and only put a small pinch in each batch. Going back to rebar on the next pour. Not sold on this idea.

I had no problem with clumping like mentioned by people who probably didn’t mix this product properly. My slab came out amazing I see no fibres sticking through and I used double the recommended weight. Highly recommend this product for any slab pours/caping.

Great product. Used to strengthen concrete countertops. Shipped very quickly.

worked well in the application. Will need to see how it holds up.

Very good product to add to cement as you are mixing it. Adds and extra reinforcement factor to the concrete above the rebars use. Still use rebar but adding this will make sure it solid no cracks. Did a walkway with last year and it solid no cracks. I do want to add one thing on the mixing process; do not use a drill wand mixer as it will just pick up all the fiber around the drill end. We mixed everything in a large wheel barrel with shovels. Or you could use a cement mixer machine.

I use the fibers to add a dimensional strength to my outdoor concrete countertop in addition to a wire mesh. The fibers separated easy and mixed very well. I used an electric drum mixer. However I did not follow the suggested usage of one bag per cubic yard but instead used the entire bag content for 7 cubic feet of concrete. None of the fibers are sticking out. Only time can tell if the fibers do the job but for now the entire slab dried and cured without cracks.