7 years in the waiting i get to start my 42" pompeii

[Caliea]

I'm lurking on your thread too, Leetheldc. I'm getting close to finishing my dome, and have started to think more seriously about the concrete countertops we're planning on pouring. I know exactly what you mean about 'looking too much!' There's great advice out there, but it's hard to keep it all straight. I've been looking a lot at the Cheng concrete website, and just ordered a few bags of their "Pro Formula Concrete mix". As I understand it, it has all the plasticizers/colorant/whatever in it to make bagged concrete suitable for a countertop application. I'm going to do some test pieces in the next week or so and try to get a feel for what I'm dealing with.

Looking forward to see your results! Good luck and thanks for sharing your experiences here!

[leetheldc]

Yes I've hammered Google with searching concrete counters and to be honest I've looked too much and boxed my own head in with it! So many different ways and opinions I'm now abit lost I think I need to have another search and try to stick to one method the things I have taken on board are: sharp sand for the sand mixed 2 to 1 with the cement , around 5 to 6 percent of pigment to cement. Stainless steel ladder wire for the thin counters. Superplasticizer to reduce the water amount.Slurry coat at 200 grit not before which is going to be a big point for me as I have wooden lettering to go in the landing piece form to be filled at the point with another colour naming and dating my oven. Maybe the agents react with the melamine in some way or because it's coating is so dense it doesn't adhere il try the veg oil on my test piece see how it goes

[Gulf]

Those forms look great! Yes, you will definately need some help flipping those chunks. They will need some good reinforcemet. It's been a few years since I did my shelves. I looked at a lot of Buddy Rhodes and Fu-Tung Chen videos back then. Are you looking at any of those videos and sites for tips? If not, it would be a good idea. I did a search this morning to see what they were recommending for a release agent these days. The Concrete Countertop Institute Blog says not to use a release agent in a melamine form. I'm not sure why?

I'm looking forward to seeing those finished counters .

[leetheldc]

I got a load of the shells from eBay ready cut didn't cost much at all there is some great ones I'm going to use in the final pieces. Il keep that in mind about pre filling them. Looking at my final forms the size and angles I have on some of them I'm defiantly going to need that month you say to let them dry I did post a pic of the forms it seems to have gone. Here it is again the 2 big pieces that go round the oven will be a pain they are massive think I might need an army to help me flip them !

[Gulf]

Lee,

Sorry, I did not see post #252 until just now.

I have one of those it didn't come with any attachments though but il give it try did you just blow it down the seams?

I remove at least 3 sides and try to nudge the cast sideways. That usually does it. If not, I give it a few blasts of air down the longest side. Aim the the nozzle at a 45 degree angle between the cast and the bottom of the form. I would not use the air on a cast that hasn't cured for 3 or 4 weeks. It could blow some small chips loose. I'm jumping back and forth from small test casts to the larger casts. So, please bear with me . Your final pour needs to set 28 days before you try to release and flip the cast imo. Have some help with you if it is a fairly large piece. That is insurance for the cast and also for your back .

[Gulf]

Looks great! Did you cut the shell? One trick that I used was prefilling the shells with colored concrete a week or so before. That gave me less to worry about during the big pour.

[leetheldc]

I got the other test form prepared I just dotted a small dab of the caulk to the form like you said joe and the mother of pearl stuck in place great I have high hopes for this one il try to get some soap oil or some release agent tomorrow and maybe get it filled I have one sample left of the metallic pigment not the colour of choice but I need to see how it polishes And if the metallic shows before I go for the counters

[leetheldc]

I have one of those it didn't come with any attachments though but il give it try did you just blow it down the seams? Yes I suppose I should have used some form of release agent il take more time on the next test piece I can just flip the form pieces over and use them again I got some caulk so il have a go later on after I seal my paving. I will defiantly oil the edges I've got plenty lying around cheers for that one

[Gulf]

I have one of those dust blowing attachments. It came with a couple different size needles. I don't think that I acturally had a needle on it when I used it to help separate the forms. Looking back at my build, I think that I waited close to a month for the trickier shelves to cure.. There are better release agents out there. But, I carefully wiped vegetable oil on as much of the forms as I could without getting any on the sides of the glass and shells. Here is the only pic that I have of the dust blower attachment. When you do your final forms, you will want to seal the edges of the melamine so they don't take on water and swell. I taped mine. But, coating them with an oil based paint would probably be better.

[leetheldc]

Lee,

I may have had larger objects to apply to the form than you. What ever I was sticking to the form, I applied only the bare minimum of acrylic latex caulk to stick it in place (not enough for it to squeeze out from under the object). I did not have any problems with any of the deco pulling loose from the concrete. I think that I waited about a week to remove the shelves from the forms. I removed the side forms before trying to remove the shelves. If you have an air compresser and the right needle attachmet, you can use compressed air to help separate the shelf from the form.

Ah caulk yes o didn't think about that il pick some up today and have a try with that. I do have a compressor but not sure which attachment you mean is it like a ball inflating needle?

[Gulf]

Lee,

I may have had larger objects to apply to the form than you. What ever I was sticking to the form, I applied only the bare minimum of acrylic latex caulk to stick it in place (not enough for it to squeeze out from under the object). I did not have any problems with any of the deco pulling loose from the concrete. I think that I waited about a week to remove the shelves from the forms. I removed the side forms before trying to remove the shelves. If you have an air compresser and the right needle attachmet, you can use compressed air to help separate the shelf from the form.

[leetheldc]

So I poured some test slabs and made a f up I used spray adhesive to stick the mother of pearl down and the glass but I used way to much as it has held most the aggregate to the form resulting in the pic a rough face slab i have taken the forms off a bit early maybe that hasn't helped. I have another slab I have done il let that set another day or so see if that is any better but I don't have much faith in it think I might have to do another test peice and spend a little more time maybe dotting the pieces down with silicon. I also cracked the slab getting it from the bottom form. I also spent yesterday making 12 corbels for my wood gutters just finished sanding the last one so all ready for oiling

[thevance53@gmail.com]

Oh, found the perlite at Lehi Block, if anyone in Utah was interested.

[thevance53@gmail.com]

Yes, I have 1" of cf blanket and I will put approx 3" of p-crete over that. I have the CF rope gasket for the heat break as well. Thanks, don't want to hijack this thread.

[UtahBeehiver]

Mike, even though I had a rotating template, I agree with David that you can achieve good results with hand work. Are you installing cf blanket underneath or only vcrete?