[jgray152]

This is something that has been bugging me and I think it may be due to the extra calcium in the redi-mixed concrete compared to the very little in portland cement??

Anyone know the reason? If I mix portland cement and sand together to get a grout mix which I use for my faux rock retainer walls, it will usually cure a dark grey or mild dark grey where as if I get it delivered from the concrete company it cures very white which is better for acid staining.

 

[CJKarl]

I have found it to vary from....Manufacturer of the cement, quarry that mined the sand and even how much water is added to the mix.

 

[jgray152]

hmmm. Well thats a bummer. I usually mix my home made concrete mix real dry for strength. Is it possible if using a lot of sand or maybe a lot of silica or another fine filler to allow the cement to maybe not be so dense or turn it white or at least a light grey? I have got portland / sand to turn white after 3-4 days of curing but that is not always the case, I guess I got lucky on that mix.

 

[6stringmason]

I have found it to vary from....Manufacturer of the cement, quarry that mined the sand and even how much water is added to the mix.

Same here.

 

[user50444]

slag mixes get really white. pretty much every redi-mix producer is either adding fly ash or slag, unless you tell them straight cement.

 

[CaliDesigns]

Your percentage of portland in concrete is a lot less than your slurry mix. That's why a lot of concrete guys add white portland to their slurry mix to wet face steps.

 

[concretemasonry]

Mortar color is highly influenced by the sand color, while ready-mix is not because of the difference in the cement content. The lightest mortar will be a traditional portland/lime mix that has more workability and long term healing from the weather.

 

[naptown CR]

This is something that has been bugging me and I think it may be due to the extra calcium in the redi-mixed concrete compared to the very little in portland cement??

Anyone know the reason? If I mix portland cement and sand together to get a grout mix which I use for my faux rock retainer walls, it will usually cure a dark grey or mild dark grey where as if I get it delivered from the concrete company it cures very white which is better for acid staining.

Portland cement comes in two colors white and gray. next time by white portaland.

 

[jgray152]

I know it comes in gray or white in bags but thats why it didn't make sence that portland in redi-mixed concrete trucks cured white or very very light gray where as portland in backs mixed roughly the same way cured gray or dark gray.

Its just something I will have to keep in mind thats all. White Concrete here is about $22 a bag verses $9.80 a bag of standard portland.

 

[harpomason]

thanks for asking as i have pondered over this same thing. I like my work to be consistant through out the job. Its one reason i try to avoid using dye or powdered color. when i can't talk them out of using it. I will measure very carefully every mix.
The man who schooled me on this trade told me that he remembers when a bag of masonry cement cost him 75cents and portland was $1-$1.25 per bag.

 

[jgray152]

Bringing this thread back as I want to find or make something that can be lighter in color other than spending $22 a bag on white cement. Home Depot does not carry it anymore so the only place I know I can get it is an hour away instead of 25 minutes away.

Masonry Cement I have read has more lime in it? Lime I read can make the cement whiter? So is masonry cement lighter in color than gray portland cement

I will be using Perlite in my lightweight mixes for now on which is white so that would help as well.

If I were to mix White cement and Grey Cement together...what proportions should I mix at? Anyone have experience with this?

 

[Tscarborough]

In my area it is, but only by a tiny amount. You can buy titanium dioxide to lighten it if you want, but it is not cheap either, about 10 bucks per bag of portland used.

 

[6stringmason]

Save yourself the headache and go get the white portland. Then charge more for your products containing the white portland.

 

[superseal]

White is what your looking for - buck up or cut it 50/50 25/75 if you a cheap azz

 

[masonlifer]

I've been using a mix with white portland to patch precast. Most of the time suppliers in this area don't keep it in stock unless someone places a large order. It's too expensive to sit in a warehouse waiting for someone to use it a bag or two at a time, and if not used soon enough it gets hard.
One source I have found is the local pool supplier. They keep some in stock for repairs on pools.

 

[Tscarborough]

Funny how very different areas are. We go through a couple of trucks a week of white portland and masonry, and we are slow. Plus our gray portland/masonry is very light.

 

[jgray152]

Funny how very different areas are. We go through a couple of trucks a week of white portland and masonry, and we are slow. Plus our gray portland/masonry is very light.

Its aggravating... I think I'll start ordering portland from china, probably cheaper and lighter!

What brand of portland do you use Tscar?

 

[Tscarborough]

Lehigh, but I have sold imported white from Turkey. Not reliable enough for our volume though.

 

[stacker]

i agree with six.bite the bullet and buy the white.when i manufactured stone,and when we had an order for white stone,thats all we used.white portland and haydite.altho my dad did experiment with puting a gallon of white paint in with regular portland once.i didnt work:whistling.

 

[Tscarborough]

If he had used just the pigment KX, Titanium Dioxide, that made the paint white it would have worked but he would not have saved any money.