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21

My only guess is that a watery mix will have the layers settle in their different sedimentary layers with the fine cement settling to the bottom... One reason is that the aggregate can settle to the bottom much too easily, yes. This is called segregation and results in non-cohesiveness of concrete. Another reason too much water is bad is that it can ...


14

Color This is the easy one. If you're going to use dark grout, you can use grey thin-set. If your grout is a light color, or you're installing glass tile or a porous stone, use white thin-set. If you use grey thin-set with light grout, glass, or porous stone, the color may show through. To modify, or not to modify In most cases, you'll want to use some ...


13

It certainly is acceptable to do a tile job in phases. There's no structural reason that tiles need to have their supporting mortar connected mechanically. The critical bond is to the substrate, not adjacent tiles or mortar. Large residential and commercial tile jobs are done in stages every day, and with no special procedures or materials. One caveat ...


12

It's all about particle size, which is classified using the Wentworth scale or The Krumbein phi (φ) scale. Sharp Sand Sharp Sand, also known as Concrete Sand is a coarse sand with larger particles. This type of sand is typically used in concrete. φ scale - 1 to 0 Size range - 1/2 to 1 mm (0.020–0.039 in) Builder's Sand Builder's Sand, also known as ...


11

The white powdery substance is called efflorescence. It's bascially mineral salts leaching out of the masonry. The efflorescence itself may not be anything more than a cosmetic problem, however the appearance of efflorescence indicates that there's moisture present in the masonry. This is not entirely surprising--you're talking about an old brick wall ...


11

If you have a pulley and no way to anchor it overhead, you could always lift from the top, with the pulley attached to the bucket. Of course, you'll need to have an anchor for the rope somewhere on the floor you're at, but it only has to be at the height you want to lift the bucket to. The resulting load will be half of the bucket that you're lifting. If ...


9

The reason is because of the hydration chemistry that takes place in the cement while it cures. When cement cures, it doesn't really "dry", the way a towel dries, but instead it reacts, the water ceases to be water and merges with the substances in the cement to form new molecules. Having too much will disturb the chemical interactions taking place and will ...


9

If the mortar is crumbling and flaking, it MUST be removed. It is a tedious job, bit to assure a good solid surface, you have to remove all loose mortar, key it, and point all the joints. Let it cure a few weeks, be absolutely it is dried, then go for the finish. If you don't get to a solid base, you will be wasting your time and paint. Remember, the right ...


7

If you do it your self (not endorsing, and see comment by The Evil Greebo) you could put a more secure plug in by using hydraulic cement. To ensure that it does not come out, holes or cracks are usually back cut (the hole is made wider below the opening so that its diameter is greater than the diameter of the opening). This can be done with a small masonry ...


7

Mortar is not waterproof. However, there are products that can be applied to mortar (and other concrete materials), that can make the mortar waterproof.


6

I have been a practicing stone mason for fourty years and I have seen the long term affect of the 1:3 mix compared to the 1:2 mix. With proper preparation from the base under the footing and throughout the build, I recommend the 1:2 mix particularly with flagstone and surfaces that are going to experience a lot of weather. My experience is almost ...


6

you can certainly stop for the day. the things you have to watch are: a) finish your tiles all in one line or row, not on the diagonal. that way you can check it with a laser or string to make sure everything is straight. once it sets, you can't nudge tiles to get a good line. b) depending on your pattern, you may have adjacent joints lap one, two, ...


5

I have been working on my field stone basement as well (170 years old), and here is what I have learned: Having hired an actual stone mason (that's right; they still exist) to repair an area of wall that was very decrepit I learned some things that are helping me now, and I have also learned that some of what he was doing was not necessary. I have begun my ...


5

Next time, tamp the cement into the corners (using a putty knife, large screwdriver, gloved finger, etc.) after a couple inches is set down. If you wait until the form is almost full, it forms stronger bubbles and they are harder to coax out. Structurally, the curb is more than strong enough unless you anticipate automobiles driving over it. The major ...


5

Considering how little exposure you will get to the mortar for your small project, you're probably fine with just your work gloves. Wearing latex gloves under your work gloves will provide additional protection. I would suggest that for the people who will be working directly with the mortar. Big picture, more important than gloves is breathing protection. ...


5

Lift the dry materials, run a hose for the water, mix in place, avoid having to lift the weight of the water. The REALLY EASY but rather expensive method - hire a concrete pump truck for the day.


5

I had a project some years back building a 28 foot high chimney. Needless to say there was a need to hoist a lot of buckets of mortar and then all the chimney blocks and flue liners up to the work site. I ended up renting some scaffold bracket assemblies that came with a overhanging cross bar with a large pulley hanging on the end of it. You could try this ...


4

Figure 5 shows the effect of porosity caused by excess water. http://matse1.matse.illinois.edu/concrete/prin.html I recommend reading the entire article. "The strength of concrete is very much dependent upon the hydration reaction just discussed. Water plays a critical role, particularly the amount used. The strength of concrete increases when less ...


4

The less water the better, to a point. Excess water will weaken the mix. At some point in the other direction, there is not enough water for the hydration process(around 0.25:1 water:cement). In general though, to have a workable mix, there will be enough water for hydration. Use as little water as possible to make a workable mix, around 0.45:1 is fine. Don'...


4

You probably (and hopefully) have a large amount of sand/grout stuck in the P trap. If so your best bet would be to remove the P trap and give it a good thorough cleaning (out in the yard, with a hose). (While the trap is off you'll be able to inspect the tailpiece and the drain line as it goes into the wall and clean those up too if necessary.) If you can'...


4

It depends on the concrete permeability and the tile permeability (is it porcelain (essentially zero permeability) or a ceramic bisque (most non-porcelain tiles))? A sealed concrete floor and a porcelain tile will greatly extend the cure cycle by limiting moisture migration. It is for this reason that Schluter (a tile membrane manufacturer) specifies a ...


4

In my years in the construction trade, here is my synopsis of concrete floats and trowels and their uses. I will start with the screed. A screed can be as simple as a short piece of framing, 1X3 or 2X4, long enough to go from side to side of a concrete form, whether it be for a 12" thick foundation or a 3' wide side walk. For larger poured slabs the screed ...


4

Since you're working with other minors, at a very minimum, you should follow OSHA guidelines: Skin Irritation: Wet portland cement can cause caustic burns, sometimes referred to as cement burns. Cement burns may result in blisters, dead or hardened skin, or black or green skin. In severe cases, these burns may extend to the bone and cause disfiguring scars ...


4

Yes, mortar is waterproof. It is "relatively unaffected" by water "under specified conditions". Water-proof or water-resistant describes objects relatively unaffected by water or resisting the ingress of water under specified conditions. –Waterproofing, Wiki However, anything claiming waterproof is likely a long way away from being watertight or ...


4

Probably not a good idea. As you said, the stones are heavy. If you could guarantee a solid rest on the floor, maybe, but I'd simply cut out the drywall a few inches inside your stone area, replace it with 1/2" cementboard, and call it good. This would be simpler than the wire lath business. I'd float backing at the joint of the cementboard and drywall to ...


4

Contact of the bottom of a steel tub with a mortar bed could cause corrosion of the tub from the bottom. If the instructions do not call for a mortar bed, I would not use it without expert opinion to the effect that it is a benefit. A good quality steel tub does not need the support of a mortar bed.


4

Tile mortar is actually fairly soft. If you have access to a belt sander, take a coarse grit to it. Otherwise, scrape at it with a robust flat tool like a cold chisel.


4

Tapconing into a mortar joint is to be avoided. See the discussion here. And the one here about how 3/16" are garbage. Use 1/4". If the Tapcon goes into a mortar joint it's pull out strength will depend on the compressive PSI of the mortar and the depth of the mortar joint in combination with the length & diameter of the Tapcon. – forums....


4

For something as substantial as a mantle, I would not use simple Tapcons. Tapcons are great for simple fasteners, but aren't that great for something like this. I would highly suggest installing a sleeve anchor of some sort. You'll get better traction on the brick/mortar and it will penetrate the surface easily. If you're absolutely set on using Tapcons, I ...


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