Concrete Mix Question Fire Clay

[Taye]

So I have been messing around with stuff to get a vertical mix to work so far nothing is going well.

It just seems that the mix is not sticky enough so it is hard to stamp and hold. It would slide off  all the time. I do use a scratch coat and diamond wire.

My question do you think fire clay would help make it more sticky? I read that fire clay can be be added to mortar to make it more sticky.

If not what can I add to make it more sticky and hold better?

any admixture?

My mix

I use  1part portland, 2 part sand, 1 part perlite, some polymer, some plasticzer.

It so hard to stamp and it slide off all the time.

any help would be great, i am on the end of the stick and am about to quit.

premix bags are out of the question because they are too expensive to ship.

Other products like SpecMix, customFloat is not sold at my home depot or lowes.

Thanks!

[Gabe Polanik]

with out a good scratch coat,it doent matter what mix you use!

[Taye]

i have a scratch coat, and i even use bonding stuff on the surface. The stuff slides off  when i try to go thick.

[Gabe Polanik]

too wet, if it slides  trys add a little lime, Nathan shows the exact procedure on his subscription!

[Nelson Lasaosa]

Hi Taye,

This is my view points:

1- More info needed for pros (not me) to give you advise. Pics of your mix over scratch coat would be helpful

2- What about the sand, is it coarse, river type or what.

3- Perlite grain size?? Is it expanded perlite ? 

4- Did you run different mixes say like three different ones as a start point to get your base mix and do fine

    adjustments thereafter'

5- Did you wet the scratch coat before throwing your mix lump on? This would work against you, sliding off too.

6- I would decrease the amount 0f water, increase the ratio of fine ground expanded perlite, decrease the amount of screened river sand, add  like   

     25% the amount of   ( perlite + sand) in fire clay.  If you get a light sticky, moist not soaky lump of your mix, sling 

     it on your scratch coat and give thought as to what could be happening. If it slides off it could be due to lack of 

    stickyness (adhesion), too much water, or too heavy a mix. If you`re using fine groun expanded perlite, the 

    weight of your mix should not be an issue, because your final resulting weight will be at least 3 times lighter than

    regular masonery mixes. Run small amounts of different mixes, writing down your exact quantities of each of your 

   engredients, and you will arrive at a mix that works best for you. Good luck. Hope to be of any help. Folks here 

  may provide sound advise.

     

[Taye]

I wish I could subscribe  but, i cant afford it at the moment. It quite expensive. 

I heard that if it too wet it surface cracks. So i don't add water at all. All i use is the polymor and it get wet enought.

Should there be water+polymer?

I usually mix it drain and add plaszier to make it more wet.

Gabe Polanik said:

too wet, if it slides  trys add a little lime, Nathan shows the exact procedure on his subscription!

[Taye]

Fly Ash is so hard to find around here. I been looking everywhere but no clue where I can buy it locally.

I live in Hayward, California 94541, if anyone know where i can get some fly ash locally it would be great.

Mark Whitten said:

If you can find fly ash were you are it will make your mix sticky.

[Taye]

Thanks very much for your tips.

My mix, I use stuff I can buy at Home Depot.

 2 part number 30 cleaned silica sand

 1 part clement type 2 - 4

1 part perlite Home Depot Perlite this is what I use from Home depot. Only stuff I can find.

i use polymer, no water 

little bit of plastizer.

I have tried different mixes to see what works. But none works so far.

1. mortar mixed with more cement, and polymer, no good

2. Top sand mix with a bit of type s mortar and polymer, no good

3. 1 to 1 cement and sand, no work.

I dont add water to mix, only use polymer to mix. Should I add water?

So fire clay will help? and lime will help?

thanks!

any more tips to make my mix more sticky would be great!

Nelson Lasaosa said:

Hi Taye,

This is my view points:

1- More info needed for pros (not me) to give you advise. Pics of your mix over scratch coat would be helpful

2- What about the sand, is it coarse, river type or what.

3- Perlite grain size?? Is it expanded perlite ? 

4- Did you run different mixes say like three different ones as a start point to get your base mix and do fine

    adjustments thereafter'

5- Did you wet the scratch coat before throwing your mix lump on? This would work against you, sliding off too.

6- I would decrease the amount 0f water, increase the ratio of fine ground expanded perlite, decrease the amount of screened river sand, add  like   

     25% the amount of   ( perlite + sand) in fire clay.  If you get a light sticky, moist not soaky lump of your mix, sling 

     it on your scratch coat and give thought as to what could be happening. If it slides off it could be due to lack of 

    stickyness (adhesion), too much water, or too heavy a mix. If you`re using fine groun expanded perlite, the 

    weight of your mix should not be an issue, because your final resulting weight will be at least 3 times lighter than

    regular masonery mixes. Run small amounts of different mixes, writing down your exact quantities of each of your 

   engredients, and you will arrive at a mix that works best for you. Good luck. Hope to be of any help. Folks here 

  may provide sound advise.

     

[Don Hansen]

I got fly ash from my masony supplier. I had to tell them what is was and then they found a place to get it. It depends on what % of solids in polymer whether to add water or not. The most common full strength polymer is 44-48% solids. The you can dilute it 2-1 up to 5-1 with water. Some polymer is only 20-30% solids so you can not add as much water. If you do not add water to a high solid polymer you are wasting money.  Another source for fly ash is a concrete (ready mix) company.

[Don Hansen]

Silica sand is too fine and expensive for rock carving. Use masony or morter sand that you can get at a  block  (building material) company.

[Jeff Tobler]

Taye,

Try a little thinset (tile setting mortar)

1/2 shovelful thinset

1 shovelful portland

60 lb bag quikrete mortarmix

This works decent for a locally available mix.

[Taye]

Hi Jefff

I really appreciate the tip.

is the Tile setting mortar sold in a bag? called thin set mortar?

Jeff Tobler said:

Taye,

Try a little thinset (tile setting mortar)

1/2 shovelful thinset

1 shovelful portland

60 lb bag quikrete mortarmix

This works decent for a locally available mix.

[Jeff Tobler]

dat be da stuff

Taye said:

Hi Jefff

I really appreciate the tip.

is the Tile setting mortar sold in a bag? called thin set mortar?

Jeff Tobler said:

Taye,

Try a little thinset (tile setting mortar)

1/2 shovelful thinset

1 shovelful portland

60 lb bag quikrete mortarmix

This works decent for a locally available mix.