Starting new 36" build

[deejayoh]

Re: Starting new 36" build

Following Russell's approach here - I got the pigment and the fiberglass additive all weighed out and bagged for the big pour. 250g of "Smokestack" pigment per 80lb bag of mix, and 10g of the fiberglass. The second one seems pretty minimal - but the instructions called for 1lb per *yard* of concrete. 45 bags per yard, so each bag gets 0.02 lb of fiberglass. Hopefully my math is right, or someone will correct me!

[dvm]

Re: Starting new 36" build

I lost a day to digging out the bamboo that had grown under a retaining wall in into my yard. It grew thru 4 feet of dirt! I dug a 5 foot deep hole, picked out all the rhizome I could find, and poured in some herbicide for good measure (I don't have anything growing that deep...) Capped the place where it got into my yard with 8 inches of concrete. Hopefully that will do the trick! Running bamboo is not something you want in your yard around here. It grows all too well.

Tomorrow I will get my forms all corner caulked, the reinforcement in place, the concrete on site, and the pigment weighed in prep for an early sunday pour.

Wish me luck

I can't help with the answer to the fiberglass additive question - though I am looking forward to the answer. I don't think you will need any luck with the cement pour - your skills will win the day... the Bamboo however could be a big problem. I once waged a 4 year battle with Bamboo at a rental house in Davis CA while attending grad school - the Bamboo won - Good Luck with THAT!

[UtahBeehiver]

Re: Starting new 36" build

Stone work looks very nice. Good luck tomorrow, fyi there is a pigment calculator on directcolor's web site for calc pigment per bag of concrete. I have been polishing with 50 grit now moving to 100, going to prepare some colored slurry to fill in the bug eyes. Looking forward to seeing the counters

[deejayoh]

Re: Starting new 36" build

I can't help with the answer to the fiberglass additive question - though I am looking forward to the answer. I don't think you will need any luck with the cement pour - your skills will win the day... the Bamboo however could be a big problem. I once waged a 4 year battle with Bamboo at a rental house in Davis CA while attending grad school - the Bamboo won - Good Luck with THAT!

I think I won this battle. We will see about the war. Since my house is higher than the neighbors who planted the weed, I can make liberal use of herbicide to kill anything growing that deep . I put a piece of PVC pipe into the bottom of the hole just in case there is a rematch.

Russell -
thanks for the tip on the calculator. I found that and used. I have a "5 Lb" color, so it's quite a bit of pigment. You definitely don't want that stuff to get on anything! I put down a big sheet of paper, and covered the scale in plastic. Still got all over my hands.

[deejayoh]

Re: Starting new 36" build

Countertop update:

I got the concrete for the countertops poured yesterday afternoon! Well, more like "positioned" as the countertop mix is pretty stiff stuff. It would hold it's shape when dumped into the form out of a bucket. Very little slump! I tried using the recommended amount of water per the instructions (1g per 80lb bag) and it would not even mix in. I probably added 50% more water than called for in order to get it to mix with some workable consistency. At the end, I didn't have any water at the surface so I think it will be ok. I guess what I did was technically GFRC, since I used both fiber mesh and cut strands in the concrete.

The cast-in-place section went well. I hard troweled the finish and I think it looks pretty good. Where the concrete meets the existing wall, I used a piece of galvanized "z" flashing with some double stick tape as a temporary form to create a slot. For the final join, I bought some Schluter metal tile edging that will go into the slot created by the flashing for the finished product. I plan to secure it with Silicone Caulk. I did make a mistake with the pigment - adding only one of the ziploc bags to each batch instead of two. So the final product will be a bit lighter than planned, but I can live with that. It was also tough to screed the section, since there was no back wall - but I laid tape there as a guide before the pour and I think I got it pretty level. Passed the eyeball test which was all I needed


Pouring the precast section for the landing was super easy. Two bags of concrete, easy screed, and easy to vibrate the mix into the form. I did not use any aggregate in either section - but in this one I decided I wanted to put a tile mosaic in front of the oven opening - so I placed a piece of ~4.5' x 8" x 3/4" piece of melamine inside the form to create a space for an inlay. It's going to say "I Cinquanta Passi" (Italian for "The Fifty Steps") - which is what I call my oven since there are fifty steps from the street to my backyard. The picture shows the bottom of the counter - and you can kind of see the grid from the Glass Fiber that I used for strength.


Looking forward to getting the forms off and the first pass with the grinder to see how things look.

Russell - if you see this, can you provide a link to the sealant you chose for your counters? Would love to piggyback your research!

Dennis

[Gulf]

Re: Starting new 36" build

Dennis,
What you experinced with the "slump" of the counter top mix with it's recomended amount of water is very interesting. I found this video a few days ago.
Concrete countertops: How cement particles are like socks. - YouTube
The video refers to Superplasticizer. That is above my paygrade and I am still going to school on that one. I had already decided to make my own countertop mix from white portland cement. I have already bought a fortifier made by sylka which replaces the water added to to the concrete. I plan to do a small test with it before I commit. Maybe someone else can shine some light on the fortifier/plasticizer subject.

[deejayoh]

Re: Starting new 36" build

Interesting. I used QC specialty countertop mix, which has the plasticizer in it. I used a barrel-type mixer. At the recommended water ratio, the mix looked like his first example. After adding 25-50% more water - the mix was more like what you see in the Buddy Rhodes video that is also on Youtube. Dense, but workable. It did not "form itself" as he shows.

[Gulf]

Re: Starting new 36" build

Thanks for the info DeeJ,
The concistency in the Buddy Rhodes video is sort of what I want to achieve. I'm not looking for the fluid type shown in the Concrete Institute vid. but, maybe somewhere in between .

[UtahBeehiver]

Re: Starting new 36" build

DeeJ,

The lithium food safe sealer is at the same place the pigment color calculator is located at (directcolors). We get in trouble by putting direct links if you know what I mean. Just go to directcolors site and look under sealant. 1 quart $31 bucks incl shipping good for upt to 450 sq ft. BTW, nice pours and hard trowel..........!@!# i am still polishing but time to fill in bug eyes with a slurry before I go farther.

[UtahBeehiver]

Re: Starting new 36" build

Gulf,

I used super plastizer in my pour, roughly 100 grams per 2- 60 lb batch of concret. To be honest, the 1/2 bag I had to run to ACE because I was short was easier to work and finish. But that could be user error.

[Gulf]

Re: Starting new 36" build

Did you get your plasticizer from Ace?
Edit: Reread post. I think that you meant that the concrete that you poured without the plasticizer was easier to work?

[brickie in oz]

Re: Starting new 36" build

Maybe someone else can shine some light on the fortifier/plasticizer subject.

Its just use dish washing detergent, it breaks the surface tension so all sand/cement/gravel particles are evenly coated in water, you use less water per mix, I used it for years.

[david s]

Re: Starting new 36" build

Super-plasticiser allows you to add the correct amount of water to the mix. Typically a ratio of around 0.5 of water to cement by weight is about right. If you mix it up you end up with a brew that seems too dry and won't flow. Adding water to achieve this results in a weaker product. Adding some super plasticiser thins the mix out and makes it flow. Too much however creates separation (heavy aggregate falling to the bottom). There are many specific chemicals to achieve this characteristic and the products have been designed accordingly. Be wary of using dish washing liquid, which has been designed to wash dishes. Although it works it probably contains phosphates and other chemicals which may have adverse effects on the concrete product either short or long term.

[brickie in oz]

Re: Starting new 36" build

Be wary of using dish washing liquid, which has been designed to wash dishes. Although it works it probably contains phosphates and other chemicals which may have adverse effects on the concrete product either short or long term.

Ive asked everyone who quotes this to provide the written scientific evidence, after 30 years Ive never seen it?

Hear say wont do.

[david s]

Re: Starting new 36" build

Ive asked everyone who quotes this to provide the written scientific evidence, after 30 years Ive never seen it?

Hear say wont do.

I'm not an industrial chemist, but if you check the chemicals these products contain and you usually have to research their data sheets, you find that the chemicals vary considerably and all have ridiculously complex names. So I defer to those applied chemical engineers and trust that the product they've designed for the application is suitable.
If there are any applied chemists on the forum, maybe they might chime in.