Concrete Countertops Blog
Most of the Precast students have stayed on for the rest of the week, and we gained a Precast alumni who has returned to take the GFRC.
The students are out in the shop now, watching/doing a demo on hand-packing and spraying GFRC sink molds. Each student will have their own sink to make, and will learn all of the basic techniques involved in GFRC production... and a few techniques that only an experienced expert would know! Students are already planning how they will incorporate what they've learned this week into their business.
GFRC is great for so many reasons... you can use recylced materials, it's lighter weight, less density, you can make fantastic shapes and designs without the stress of trying to reinforce it with steel... plus, start-up costs are very low!
*Video clips to come soon*
Precast class, day 3: Jeff has the students in the classroom today, going over their mix calculators and formulas...
The end of the Precast class approaches! Students have been in the classroom all day, going over the science behind the mixes and formulas, and treatments, etc. It's amazing how much can be learned in just three days!
In a while we'll go out to the workshop and take a look at the pieces that were cast yesterday. They are not done curing yet, but they have hardened to the point where they can be installed in the mock kitchens, for the purposes of the demo. The students will be able to see what their hard work accomplished! And they'll get to experience the joys of hauling a 300 lb top around, and manhandling it into place--without damaging the property it's being installed into!
TIP I LEARNED: 2-3 days is fine for curing the average job. 7 days is a luxury, not a necessity. Be sure to monitor the moisture, and make sure it cures evenly. No leaving it flat on the casting table, make sure to at least prop it up several inches, so the whole piece stays evenly moist and cures at the same rate.
Tuesday was so busy I didn't even have time to blog about it until now!After the class lecture, we moved out to the workshop, where Jeff shows the students how to layer the steel wires into the forms. Who knew zip ties could be so useful in countertop production! I decided that, while laying out the reinforcement is great to learn, it's less than entertaining to watch.
Jeff talked a lot about layers, and mixes... made me think of cake. It was a lot like a massive baking project, come to think of it...
The students checked the oil on the tables (and made sure there were no pieces of sawdust, or any other large particles) to prepare for the pour. I love seeing the camaraderie that builds up in the groups. Students go from disinterested strangers to coworkers and friends, in a remarkably short amount of time!
The demo was done in run of the mill lunch trays, the kind you see in fast food restaurants. They are great to make samples in! Part of Jeff's demo covered ghosting, and how to avoid it. That is something even veteran countertop makers struggle with! Some of the students have been making countertops on their own for years, and say that they've already learned a wealth of valuable information, things they'd never known to do, short cuts that are efficient, not lazy.
In the workshop, it's always essential to put safety first (and fashion a close second) with safety goggles and face masks. Cement dust is not something you want to inhale too much of! Two batches of concrete are mixed, one with pigment, the other just regular gray cement. Students made the mix from scratch, of course, using sand and stone as the main ingredients. When you build every mix yourself, you know exactly what is going into it, and the condition of the elements you're adding (whether the sand is a little damp, or there are chunks in the aggregates); mixes from a bag are much less controllable. Two types of drums are used, too; Jeff prefers the steel drum; he's had the one in the shop for years, and it's still in excellent condition. Ingredients are poured in, and the mixing begins...
TIP I LEARNED: You don't need fancy or special ingredients. It does not have to be stylish. Just because something claims to be "new" or "adds" a lot to your mix, does not mean that it's not an old product that's been relabeled, or something completely superfluous. If you find a mix that works for you, and that gives you solid results, why change it? If it ain't broke.....
Once the pour is complete, and covered with plastic, Jeff brings the students to a demo piece, and shows them wet grinding, polishing, and sealing. This takes up the remainder of the afternoon, and the students are absorbing the information like sponges. It makes a huge difference in learning when you can actually put your hands on a project, and make it yourself, with an expert standing by!
The day closed with dinner & drinks downtown. Wednesday they'll learn how to make the mix they used today!
The students are in the classroom this morning, learning how (and WHY) reinforcing needs to happen. They'll be heading out to the shop soon to begin learning how to make their own mixes, using whatever is available from their local hardware stores and dealers.
Time for a coffee break.
And so the first day is complete. It's amazing what you can learn in a day! In the afternoon, we learned how to build the forms on the casting tables, after a discussion on how to make the tables, what surfaces are best to use, and why vibrating tables are overrated....The two groups set out their forms, using the templates they had made this morning. The casting tables were swept and prepped, the borders secured, the calk applied.
The students are ready to mix and pour tomorrow!
Now for chips & salsa at Lane & Jeff's house...