Countertop form ?? - Contractor Talk - Professional Construction and Remodeling Forum

DavidC · 07-21-2009, 09:00 AM

We are ready to pour our first concrete counter top, just waiting on the grinder to arrive before we do. I went with melamine to build the form thinking that it would release easily w/o oiling. Now that the moment is near I'm second guessing myself.

Care to straighten me out?

Good Luck
Dave

6stringmason · 07-22-2009, 07:39 AM

Concrete countertops are not something you want to just jump into. They are alot different than pouring a slab.

Many think its concrete, whats so hard about it, but the truth is if I had known there were going to be so many variables and things that could go wrong with countertops, I may not have ever started. But now I've spent so much time learning and honing my skill that I cant really stop.

Be ready for a commitment if you chose to do this for a living, or even side work. But that being said, please make them look good so you dont give concrete countertops a bad name.

But to answer your question, Ive never used form release with melamine and have never had any problems.

CaseyJones · 07-22-2009, 07:48 AM

I have poured counter tops for years. With melamine I would use a very thin release agent. Pam cooking spray is easy, non toxic. Spray on and wipe off excess. (Make sure not to use floured spray

).
Vasaline also works.

DavidC · 07-22-2009, 10:09 AM

Thanks gents. I was hoping 6string or Gene would chime in. I've admired the work you both have posted here.

I've been interested in the product since first reading about it several years ago. I see it as a unique offering with endless possibilities in the right hands. It took no less than 2 years to find a guinea pig customer because I've been honest about the fact that we've never done one. This client has agreed to take a chance with us and accept either minor defects or a post form laminate in the event of a complete failure in exchange for a decent discount on the value of the counter. The real pressure would be to deliver a good product this time and sell the next with no disclaimer or discount mattress to land on.

It's a simple rectangular counter top with no cut outs or bump outs, just a slightly out of square corner. We're using Quikcrete counter top mix, liquid dye and melamine form. Bought enough material for a second pour just in case. While we are at it we are making 2 desk tops for our office in the hopes that the will be photo worthy enough to help fuel more sales.

I agree that it's better to let those that can do. But once upon a time I had never walked before. I'll post the pics for your critique when finished.

Good Luck
Dave

gallerytungsten · 07-22-2009, 06:48 PM

If you don't have it already, I would suggest getting the Cheng book on concrete countertops immediately. He does suggest using melamine, although he has lots of other details, for example, running a bead of silicone along the seams.

**genecarp** · 07-22-2009, 07:54 PM

Quote:

Originally Posted by 6stringmason

Concrete countertops are not something you want to just jump into. They are alot different than pouring a slab.

Many think its concrete, whats so hard about it, but the truth is if I had known there were going to be so many variables and things that could go wrong with countertops, I may not have ever started. But now I've spent so much time learning and honing my skill that I cant really stop.

Be ready for a commitment if you chose to do this for a living, or even side work. But that being said, please make them look good so you dont give concrete countertops a bad name.

But to answer your question, Ive never used form release with melamine and have never had any problems.

That says it all, not much i can add, take your time constructing the forms, dont forget to vibrate, I could go on and on, there are so many things that can affect a pour, i have been involved with pouring tops for 3 years now, and i am still learning. I know it is hard to believe that pouring tops can be that sensitive, but it is, trust me

PS. if you have specific questions PM me i will gladly help if i can. G

DavidC · 07-23-2009, 07:59 AM

Quote:

Originally Posted by gallerytungsten

If you don't have it already, I would suggest getting the Cheng book on concrete countertops immediately. He does suggest using melamine, although he has lots of other details, for example, running a bead of silicone along the seams.

Got it already. We ordered our grinder form his website. And we have siliconed the exposed edges using a penny for consistent tooling. We will be following the instructions religiously.

Thanks for chiming in Gene.

Good Luck
Dave

DavidC · 07-29-2009, 11:40 AM

Well the forms are filled and we wait. Practiced on 2 desktops before going after the customers top.

First batch we thought looked to dry. We reasoned that we weren't using any dye in this batch and the recipe was short that much liquid. So we added 10 oz. water to make up and it went the other way. Screeding was more like scrapping of the cream.

Second batch was better looking, plastic looking and sticky. I had to be careful because the screed board was pulling material up from behind it. Charcoal in color, this and the plain one will be desk tops in our office.

Thirdly we did the clients counter. That seemed to be the best mix, moist enough to work but not to sticky or runny. This one also seemed to release the most air when we vibrated.

Made 4 6x6 blocks to play with and test out using the grinder. Tried out a couple of different edges also. Everythings covered with a plastic sheet while it sits.

I will post photos after I remember how resize them for this forum. I have some posted on Facebook if you care to look us up there.

Good Luck
Dave

DavidC · 08-04-2009, 08:27 AM

Grinding has revealed that we could have done a better job vibrating. Pinholes have shown up after the first grind with 50 grit. The mix we thought was the worst (1st, too loose) fared the best and the mix we liked the best fared the worst in pinholes.

Some holes were evident before grinding and we mixed some grout to fill them. The grout does not grind as smooth as the concrete.

For vibrating I first tried the palm sander on the edges but it didn't seem to be doing anything. Switched to a bladeless sawzall and liked it much better. Vibrated until I thought the bubbles had stopped. More would have been better but maybe the looser mix is better.

The undyed slab has the fewest pinholes and I'm moving on with polishing with wax to see if I can fill them as I wax. The charcoal I'm playing with some epoxy filler but hope thats not the way to go, hate working with it. The clients slab waits for now. Wondering if mortar mix sweetened with a little extra portland would do it.

Really liked the colors after they set up, but they are a lot lighter after grinding.

Comments welcomed.

Good Luck
Dave

neolitic · 08-04-2009, 10:10 AM

Absolutely no experience doing these,
but I wonder why no one seems
to use architectural plywood (HDO)
for the forms?
I know we used the same stuff for
slip forms on 6 different elevator shafts
(6-8 floors on 3 different jobs)
and the stuff got recycled several
times after that.
Just curiosity here.

DavidC · 08-04-2009, 12:01 PM

I am not familiar with HDO. Is it sealed or waterproofed somehow? My concern (remember I'm new at this) would be the moisture raising the grain and imprinting the slab.

On the pinholes - epoxy is not the answer, which makes me glad. However we did have to regrind the slab substantially to remove it.

In theory you can apply enough wax to fill a few. In practice it doesn't seem, well, practical. After 3 coats of wax there are still a few that linger. This slab is destined for our office where defects will most likely be covered in paperwork. A little more elbow grease and it will be done.

Our next attempt is a recipe of Portland, latex bonding and dye. Its been applied, waiting for it to set and then light grinding to remove the haze. We'll let it set overnight before grinding again.

I was dissapointed with how the color faded with grinding, but the wax brings it right back.

I've been taking photos all along but haven't had a chance to sit down and resize them for this forum. I will get to it but in the meant time you can try this link to our FaceBook page. http://www.facebook.com/home.php?#/p...8044340?ref=nf

Good Luck
Dave

neolitic · 08-04-2009, 12:12 PM

http://www.sylvanproducts.com/products/armorply.html
http://www.freemansupply.com/HDOFirPlywood.htm

"....MDO plywood is a form of overlaid plywood. What this means is that MDO plywood starts with a core of overlapping veneer, much like traditional veneer core plywood. But instead of having a surface veneer of finished woodgrain, MDO plywood features a surface layer of medium density fiber, much like MDF. The result is a sheet of plywood that can typically be used once for forming concrete.

HDO plywood

HDO plywood is much like MDO plywood, except that the density of the fiber surface layer is much greater. This greater strength means that HDO plywood can usually be reused several times for forming. Thus the density of the surface layer is the distinguishing factor between MDO and HDO plywood. "

DavidC · 08-05-2009, 03:28 PM

Thanks for the clarification Neo. I don't see why HDO couldn't be used. Any idea how the cost compare? We are paying about $35/sheet for the melamine.

Gene mentioned once about using a plastic sheet (coke bottle material?) to line the form. We set some leftover material on a trash bag, when we picked it up after setting it was smooth as a baby's a$$, wrinkled but smooth. I'd be interested in a source for the sheets.

The more we work on it the more ideas and questions I have. The possibilities seem endless. The finished product is extremely heavy. These three are relatively small pieces and I'm wondering how we'll handle larger ones. I know the granite guys that have worked on our jobs brought enough guys to brute it in, but it's easier to watch than lift.

Good Luck
Dave

neolitic · 08-05-2009, 06:55 PM

Quote:

Originally Posted by DavidC

Thanks for the clarification Neo. I don't see why HDO couldn't be used. Any idea how the cost compare? We are paying about $35/sheet for the melamine.

Gene mentioned once about using a plastic sheet (coke bottle material?) to line the form. We set some leftover material on a trash bag, when we picked it up after setting it was smooth as a baby's a$$, wrinkled but smooth. I'd be interested in a source for the sheets.

The more we work on it the more ideas and questions I have. The possibilities seem endless. The finished product is extremely heavy. These three are relatively small pieces and I'm wondering how we'll handle larger ones. I know the granite guys that have worked on our jobs brought enough guys to brute it in, but it's easier to watch than lift.

Good Luck
Dave

HDO will be more than $35.

It's just that it would last like
forever if you are building a
permanent bench to pour 'em on.
Like to hear from Gene.
You should ask him about his
lift cart deal.
Works kind of like a piano dolly.....

DavidC · 08-07-2009, 06:33 PM

Sorry, I tried to post a photo here, don't know what I did wrong.

Better than the photo is this (from our FaceBook page today):

Gari Vibber GREAT JOB!
To everyone out there... that is my laundry room countertop... and even though I left NY before it was installed today, by the miracle of technology I can sit at the dinette of our RV going down the road in Michigan and see what these AMAZING contractors have accomplished in my home.
Dave, Jon, Scott and all... thank you. Can't wait to see it in person!

Anyone looking for SUPERIOR contractors... get ahold of these creative, talented, TRUSTWORTHY guys... you will NOT be disappointed.

about an hour ago · Comment · Like Unlike · Report

Good Luck
Dave

neolitic · 08-12-2009, 11:34 AM

Bumped up...
I see genecarp is here,
maybe he can link to that
cool cart video......

DavidC · 08-12-2009, 01:04 PM

Thanks to a PM from Gene I've spent a bit of time this afternoon @ http://www.concretenetwork.com. Haven't found the cart yet, too much to be distracted with otherwise.

Good Luck
Dave

neolitic · 08-12-2009, 01:16 PM

Quote:

Originally Posted by DavidC

Thanks to a PM from Gene I've spent a bit of time this afternoon @ http://www.concretenetwork.com. Haven't found the cart yet, too much to be distracted with otherwise.

Good Luck
Dave

Have fun!

**genecarp** · 08-12-2009, 01:43 PM

Here is a link gang, G

http://www.concretecountertopplant.com/index.asp

jcalvin · 09-18-2009, 01:59 PM

I know this post is a little old, but I was looking around for some info and found this. I know absolutely nothing about concrete countertops and only slightly more about concrete for that matter. I have been toying with the idea of starting what would be, to the best of my knowledge, the only company in at least 45 miles that even offers this service. Looking for a book, manual, hooked on phonics, concrete countertops for dummys sort of thing. The local and expanded local market has gone almost exclusively to quartz or granite and I believe there would be a good niche in the market for this. Am I completely out of my mind? Tell me if I am. I want to learn as much about it as I can before I decide to get into it or not. Where can I go for some schoolin?