Mounting a Concrete Mantle, Building a Better Casting Table, and Solving Curling for Good

“With SCC GFRC and Maker Mix you do not need a vibrating table anymore - just mix, pour, and cure correctly for clean, strong, flat concrete every time.” -Brandon Gore

 

Some days in the shop call you to level up, not just in your craft but in the person you’re becoming. This episode walks with you through the practical wins that help you get there.

Brandon and Jon break down how to set paddles on a vertical shaft mixer so your fiber reinforced mixes behave the way you need for concrete countertops and sinks. You’ll hear different approaches to mounting a floating mantle or fireplace surround, is a vibrating table necessary to make concrete countertops, and why a torsion box casting table can tighten up your workflow. We also cover the simple steps that prevent curling, and which Kodiak Pro polishing pads to pair with a Dewalt sander for a clean, efficient finish.

Then the conversation shifts to something that sharpens more than your craft. Justin Burd’s Concrete Athlete Design Competition challenges you to create a meaningful piece using no more than 50 pounds of Maker Mix or RADmix, paired with thirty days of workouts and daily discipline. It’s a reminder that stronger concrete and stronger character both come from showing up with intention.

By the end, you’re equipped with better methods, clearer thinking, and the confidence that comes from choosing the right tools and the right habits. Kodiak Pro stands ready to help you make work you’re proud of and a life that feels just as solid.


#MakerMindset #CreativeGrowth #ConcreteCraft #SelfDevelopment #ArtisanLife #BuildSomethingBetter #GFRCCommunity #ConcretePodcast #KodiakPro

TRANSCRIPT SUMMARY:

3:34 – Workshop Recap: Ramm-Crete, GFRC, And Fundamentals For Concrete Countertops & Sinks

Ramm-Crete Workshop – Turning Rammed Earth Aesthetic Into Shippable Pieces

The classic rammed earth look is thick, heavy, and nearly impossible to ship. Traditional walls are 18 to 24 inches thick, which is great for architecture, not so great for a concrete sink or bench.

That is why we created Ramm-Crete, an ultra high performance concrete system that delivers the layered rammed earth aesthetic in a thin, shippable profile.

In the Ramm-Crete Workshop, we teach you how to:

  • Create the layered rammed earth look with a high performance mix

  • Keep pieces thin, strong, and shippable

  • Apply the technique to wall cladding, planters, benches, and concrete countertops

It is built for architects, designers, and makers who want that earthy, premium look without building a full rammed earth wall.

Fundamentals Workshop – Your First Step Into DIY Concrete

The Fundamentals Concrete Workshop is the first stepping stone if you are listening to The Concrete Podcast and thinking:

  • “I want to make a concrete sink or countertop, but I have no idea where to start.”

  • “What tools do I actually need?”

  • “How do I mix, pour, cure, and seal without wasting time and money?”

In a day and a half we cover:

  • Tools and setup for DIY concrete

  • Mix design, with a focus on modern GFRC and Maker Mix

  • Pouring and casting techniques for concrete countertops and concrete sinks

  • Proper curing, demolding, and sealing so your pieces last

The goal is simple. You are the hero in your own shop, and this is the roadmap that keeps you from wandering in circles, wasting bags of mix and weekends of time.

5:20 – Kodiak Pro Maker’s Holiday Haul: Smart Spending For Concrete Businesses

Brandon talks about the Maker’s Holiday Haul, a Kodiak Pro promotion that rewards cumulative purchases in November and December with custom Yeti gear.

One customer placed a $15,000 order of Maker Mix without a specific project on the schedule. Why?

  • They know concrete projects are coming.

  • They want to reduce taxable income before year end.

  • They would rather stock up on materials they will actually use than buy another depreciating toy.

This leads into a bigger conversation about DIY concrete profitability.

DIY Concrete And Profitability:

For years, Brandon’s accountant in Arizona would give him the same advice:

“You made money. Go buy more equipment, another truck, a skid steer. Write it off.”

Yes, bonus depreciation on a truck or machine can lower your tax bill, but it also:

  • Adds a big monthly payment

  • Requires insurance, taxes, and maintenance

  • Ties you to years of overhead

With Maker Mix and Kodiak Pro materials, you still reduce taxable income, but you are:

  • Buying inventory that turns into revenue

  • Avoiding long-term payments

  • Stocking materials that make concrete countertops, concrete sinks, and custom GFRC work possible

You are not just lowering taxes. You are stacking the deck in favor of future profit.

9:39 – A Potluck Of Questions From The Concrete Community

This episode is not one single topic. It is more like a potluck dinner.

Brandon and Jon pull real questions from the Concrete Countertops, Concrete Sinks, Concrete Furniture, and Concrete Tile Facebook group and walk through:

  • Vertical shaft mixer setup for GFRC and SCC

  • How to mount a floating concrete mantle or fireplace surround

  • Why you probably do not need a vibrating table anymore

  • How to cure slabs so they do not curl

  • How to set up torsion box shop tables

  • Whether Kodiak Pro Festool-style diamond pads fit DeWalt sanders

  • How the Concrete Athlete Design Competition helps makers stay healthy

Each answer is aimed at a specific problem that slows makers down. The goal is to help you move faster, with fewer headaches, so your concrete work actually supports your life instead of consuming it.

10:29 – Fiber Loading And Flowability: Dialing In Vertical Shaft Mixers For GFRC

Listener Matic just bought a vertical shaft mixer with arms that reach down into the barrel. His question:

“Do the arms need to touch the barrel, or how close should they get?”

The Short Answer

  • No, the paddles should not touch the barrel.

  • Leave about 1/8 to 1/4 inch of clearance from the bottom and sides.

Why The Rubber Pads Become A Problem With GFRC

Many mixers ship with rubber “squeegee” pads on the paddles, meant to scrape the barrel. That sounds smart on paper, but once you are mixing GFRC with fibers:

  • Fibers get trapped between rubber and barrel.

  • They build up into a thick ring.

  • Friction increases, heat builds, motors strain, and mix quality suffers.

Brandon’s own IMER 360 arrived with rubber pads touching the barrel. With SCC GFRC it squeaked, but when Jon ran a PVA-fiber ECC-style mix in it, the noise and heat were brutal. They ended up cutting the rubber back to the metal edge.

Since then, they have mixed SCC GFRC and ECC with:

  • No rubber squeegees

  • Paddles set about 1/4 inch off the barrel

No issues. No buildup. Just smooth flow.

Best Practices For Vertical Shaft Mixers With GFRC

  • Set bottom and side clearance to 1/8 to 1/4 inch.

  • Remove or cut back rubber pads for fiber-reinforced mixes.

  • Use a strong enough motor (2 hp, 220V works well for larger mixers).

  • Remember that modern SCC GFRC and Maker Mix do not need aggressive scraping to blend, they need consistent, gentle movement.

17:39 – Surface Quality In GFRC: Mounting Floating Concrete Mantels & Fireplace Surrounds

Another big question came from Mark, asking how to mount a concrete mantle. His photo showed a full surround with no hearth, which brings several mounting options into play.

Floating Concrete Mantels – Hidden Steel

For a true floating look, Brandon often treats a concrete mantle like a floating concrete sink:

  • The general contractor installs steel supports or a welded bracket into the framing, with arms projecting from the wall.

  • The concrete mantle is cast with sleeves or cores that slide over those arms.

  • No visible brackets, no drop edge to hide hardware, just clean concrete.

This approach works well for concrete countertops and floating concrete sinks too.

Thin Fireplace Surrounds – Straps Plus Adhesive

If you are cladding around a firebox with 1 inch GFRC panels:

  • Cast pieces with plumbing strap or perforated galvanized strip embedded in the back.

  • Fasten straps to the framing or masonry.

  • Back up the install with construction adhesive.

Brandon does not like relying on adhesive alone. The extra mechanical support gives you peace of mind that a panel will not come down years later on someone sitting in front of the fire.

Using A “French Cleat” For Heavy Concrete

For larger three-dimensional surrounds and mantels, a French cleat system (or just “cleat” if you are teaching in France) is incredibly strong:

  1. Rip a 2x4 with a 30–45 degree bevel.

  2. Cast the beveled 2x4 into the back of the piece, face down in the mold, making sure it is perfectly parallel with the top of the form.

  3. After demolding, cut the wood back so you have some lateral adjustment.

  4. Mount the mating cleat to the wall, level and secured into multiple studs with structural screws.

  5. Drop the concrete piece onto the cleat and fine-tune left/right.

  6. Add a bead of adhesive on the back as insurance.

Spread over multiple studs, a properly built cleat can hold thousands of pounds. The same idea works for heavy concrete wall art, concrete picture frames, or thick concrete countertops that hang without legs.

Heat, Foam Cores, And Hairline Cracks

With concrete mantels over working fireplaces, you might see small hairline cracks over time from thermal movement, but concrete itself is non-combustible and generally performs better than wood.

The one big caution:

  • If you use foam cores to make a mantle lighter, do not leave raw foam inside.

  • Foam expands and contracts with heat and can put pressure on the shell.

To avoid that:

  • Design an access hole into the back of the piece.

  • Use acetone to melt foam into an inert goo inside the void, not as an expanding block.

  • Keep that goo off the face of the concrete or you will scar the surface.

41:44 – Curing, Curling, And Keeping DIY Concrete Slabs Flat

Listener Corbin posted a painful but common story:

  • He cast a piece and covered it with plastic for 48 hours.

  • Then he removed the plastic and left it in the form, uncovered, for four more days.

  • When he finally demolded, the ends were curled up a strong quarter inch or more.

He also used a lower quality bag mix, which did not help. But the real issue was uneven curing.

Why Concrete Slabs Curl

Concrete curls when one face shrinks differently than the other.

  • One side dries, shrinks, and cools faster.

  • The other side stays wetter and warmer.

  • The piece pulls toward the drier side, like a potato chip.

It does not matter whether it is a concrete countertop, concrete sink deck, or a fireplace slab. Different cure on each face equals movement.

A Simple Curing System For Flat Slabs

Here is how Brandon cures SCC GFRC and Maker Mix pieces so they stay flat and develop rich color:

  1. Cast the piece in the form.

  2. Let it firm up on the back for 1–3 hours, depending on shop temperature.

  3. Once it has gelled, cover the back with:

    • Polyester felt

    • Plastic sheeting

    • A moving blanket

    • A low-setting Sunbeam heating blanket

    • Two or three more moving blankets as insulation

  4. Let it cook. The piece exotherms, gets hot, then slowly returns to ambient temperature over about 24 hours.

You can even use a Bluetooth sensor like SensorPush to track the temperature curve, but the low-tech version is just feeling underneath occasionally with your hand.

The Most Important Step: Demold And Flip Early

Once the slab returns to ambient temperature:

  • Uncover, demold, and flip it within 20–30 minutes.

  • Set the piece face up on foam strips so air can circulate top and bottom.

Do not:

  • Leave the piece uncovered in the form for days.

  • Set the slab on a flat melamine sheet with no air underneath.

  • Stack 2x4s directly on the face while it cures.

Those mistakes cause:

  • Curling, as the exposed side dries faster

  • Uneven color and ghost patterns where wood or foam sat on the face

If a piece is a week old and curled 1/4 inch at each end, you are usually better off recasting with a quality mix like Maker Mix and following this curing process than trying to force it flat.

50:07 – Tools Of The Trade For DIY Concrete & GFRC

Diamond Pads: Will Festool-Style Pads Fit A DeWalt Cordless?

Listener John Farley asked if Kodiak Pro diamond pads that are designed around Festool patterns will fit a DeWalt cordless sander.

Short version:

  • The pads are hook and loop, so they will attach.

  • The hole patterns for dust extraction may not line up perfectly.

A couple of tips:

  • Compare your sander’s pad pattern to the photos on the Kodiak Pro site.

  • If you want better dust alignment, use a leather hole punch to add extra holes where needed, rather than drilling and tearing the pad.

These diamond pads are designed for concrete and stone fabrication, so they pair beautifully with Maker Mix concrete countertops and concrete sinks when you need to refine an edge or flatten a surface.

Shop Tables: Why A Torsion Box Beats A Heavy Steel Slab

Listener Scotty asked about shop tables and vibrating tables in general.

Do You Still Need A Vibrating Table?

If you are still using old-school bag mixes like Quikrete for upside-down precast, vibration can help chase air.

But with modern SCC GFRC and Maker Mix, Brandon’s advice is blunt:

“You do not need a vibrating table anymore.”

Self-consolidating GFRC degasses on its own if you mix, pour, and cure correctly.

Building A Torsion Box Table

For flat, strong, and surprisingly light work surfaces, Brandon uses torsion box tables, following the classic Wood Whisperer approach:

  • Rip 3/4 inch plywood into ribs.

  • Build a grid of long and cross ribs, like a honeycomb.

  • Skin top and bottom with 3/4 inch plywood.

The result:

  • Dead flat, airplane-wing stiffness.

  • Minimal deflection under heavy concrete pieces.

  • Easy to shim level anywhere on an imperfect shop floor.

Brandon sets torsion boxes on rolling steel bases for mobility, then shims at each new location to bring them to level. For very heavy or tall pieces, he will even drop a torsion box to the floor and cast there to keep the work ergonomic.

Underneath, he often uses the “wasted” space for steel storage, so the tables serve double duty.

53:53 – Work-Life Balance For Makers: The Concrete Athlete Design Competition

The episode closes with something that does not involve a mixer, a sealer, or a grinder, but it might keep you in this craft longer than any tool:

The Concrete Athlete Design Competition, led by Justin Burd and sponsored by Kodiak Pro.

It is a fitness and design challenge for the concrete community. Last year, Brandon did not know how many people would actually show up. The answer was: a lot.

  • Makers posted daily workout videos.

  • They shared in-progress shots of their concrete design projects.

  • People admitted they were tired, then showed up anyway because they saw everyone else doing it.

This is not about who can deadlift the most or who has the lowest body fat. It is about:

  • Well-being in an industry that is brutal on your body.

  • Community, so you remember you are not alone in your shop.

  • Creative momentum, tying physical movement to concrete design.

You might never run a marathon. You might never touch a barbell. But maybe you:

  • Try your first push-up.

  • Walk more.

  • Sketch a new concrete countertop design in the notebook Kodiak Pro sent you.

You stay in motion, and that motion keeps your work, your body, and your mind a little healthier.

Closing: You Are The Hero In Your Shop

If you are making concrete countertops, concrete sinks, fire features, or custom furniture, you already know the stakes:

  • A small mistake in curing can curl an entire slab.

  • Bad mixer setup can wreck a GFRC batch.

  • Poor mounting can make a concrete mantle dangerous.

  • Buying the wrong “tax write off” can chain you to payments for years.

This conversation was never about showing off how much Brandon or Jon know. It is about handing you a clearer map so you can win in your own shop.

  • Tune your vertical shaft mixer so GFRC and Maker Mix flow clean.

  • Cure your slabs so they stay flat and rich in color.

  • Mount mantels and surrounds with confidence.

  • Stock materials that build your business instead of draining it.

  • Take care of your health so you can keep creating for years.

If you want to go further:

  • Check out the Ramm-Crete and Fundamentals workshops at Concrete Design School.

  • Stock up on Maker Mix and other Kodiak Pro materials so your next project is easier than your last.

  • Join the Concrete Athlete Design Competition and let the community help pull you forward.

You are not just pouring concrete. You are building a life. Kodiak Pro is here to help you do it with less stress, better results, and a little more joy along the way.