Marmorino & Stucco application
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Always mask before priming and plastering. Good masking will result in a razor sharp line between the plaster and anything adjacent. When masking, be sure to buy the right tape. Blue tape is the best. Don't use low tack blue tape. It generally falls off trim under its own weight. White tape is too sticky and can either leave a sticky residue on the trim or tear off the paint or varnish to which it sticks. If using white tape, make sure it's not exposed to the sun, otherwise it will over stick to the trim. On remodels, sometimes the wood is very lightly varnished and even blue tape can peel off the finish. In this case, use low tack blue tape. When masking, use a hand masker that applies paper directly to the tape. Mask about 1/16" or less from the adjasent substrate (expose a little of the trim). Make sure when plastering not to get too much plaster on the tape. This will make it difficult to remove the tape later.
TOOLS / MEANS OF APPLICATION
There are 2 ways of plastering. One, with a hawk and a trowel, and the other is with a pan and a knife (usually for drywallers). We prefer hawk and trowels.
The hawk is the pallette or square with which you hold your plaster. And the trowel is the thing you apply the plaster with on the wall. (Just making sure.)
You can buy trowels, hawks and anything else you need from most major hardware stores.
Make sure you have the appropriate equipment:
-small spatulas (or something that will get into hard to reach areas)
-box of latex gloves
-goggles / glasses (to avoid getting plaster in your eyes)
-spray bottle of water (for cleaning and extending open time)
-fine sanding sponge for sanding unburnished plaster, smoothing out corners and bullnoses.
-respirator if you plan to work with dry goods or dust from sanding
-little 2" spatula to get into smaller nooks and crannies
ALL ABOUT TROWELS
The trowel is the most important piece of equipment on your job. It can be a source of great frustration or a bad job if it's not perfect, so pay attention...
As said, you can use trowel from any major hardware store. Most trowels will work fine. Some pros would differ with this statement. The most important thing is to have a super smooth and straight edge. When you buy a trowel run your finger down the edge to make sure it doesn't have any dings or nics. Also, look down the edge of the trowel to make sure it's not bowed or wavey. All trowels are made a little diffferent, so make sure you're getting a good one.
Stainless steel trowels are preferred, but you can also use the non-stainless. Stainless steel won't rust and most importantly, they will leave less potential grey marks as a result of the metal rubbing off a little when burnishing (as will be discussed). If the plaster is getting even a little too dry when you are burnishing, a non-stainless steel trowel can leave some very dark marks, especially when doing lighter colors.
When you get a trowel, you have to sand down the edges with 220 grit or less. You can also use a fine file. Sand it until you can run your finger down the edge and feel nothing. Even sand the top edge of the trowel. This will make difference. Don't use a mechanical grinder on the edge. It can damage it. You would go through this method even with special Venetian plaster trowels. With Marmorino, when applying the first coat, the sand in the plaster will sand out most inperfections in the trowel, so you might not have to hone the trowel at all when first using it.
You can grind down the corners a little with a grinder or on concrete. This will eliminate any potential lines on the plaster left from sharp corners of the trowel. Pool trowels work well, but you need a smaller tool to get into corners.
Don't buy trowels that are manufactured with the metal 'grain' running perpindicular to the length of the trowel. These type of trowels are very hard to smooth out.
You'll be applying Marmorino with creany but thin strokes, so any imperfections in the trowels can leave some very obvious lines. Prevent any dings at all times. You can usually get rid of imperfections with fine metal files.
Again, make sure your trowel is perfect. Before you do the last coat, always test it on a sample board to make sure it's not leaving any lines or scratches.
Some recommended trowels are Marshalltown and Taskforce (pool trowel) that are available at larger hardware stores. Kobalt is not so good for Marmorino. Buy whatever fits best, wether it's size, steel or the grip.
WHAT SIZE TROWEL DO YOU NEED?
16" - if you're a pro and have more than 200 square feet to do and have a good shoulder.
12"-14" - If you're doing less then 200 square feet and you can take your time or if you have a modest shoulder.
10" or less - If you're doing a smaller intricate application with lots of variation or just need to get into tight areas.
Ultimately, just get what feels most comfortable. We can sell you a trowel, but you should definitely check the stores first. They pretty much have what we have. They have all the other tools and accessories you will need, too.