Welcome back to the NPC Smooth Finish podcast, where we dive into the pool of knowledge and fish out the pearls of wisdom! Today, we’re tackling Technical Bulletin #8, which isn’t just a number—it’s a lifeline for those braving the elements to create the perfect pool finish.

Plastic Shrinkage: It’s not your average shrinkage; it’s the villain of plaster, lurking in the shadows of the first few hours’ post-application. This dastardly phenomenon occurs when plaster loses water faster than a camel on a treadmill. To combat this, water must multitask like a circus juggler, balancing the Wick effect, curing chemistry, and the mood swings of ambient conditions.

Now, let’s talk about the Fab Five Factors that can turn your pool project into a dramatic reality show:

1. Ambient Air Temperature: It’s not just hot air; it’s a potential project melter!
2. Substrate’s Thirst Level: How quickly does it gulp down that moisture?
3. Material Temperature: Is your plaster chill, or is it having a hot flash?
4. Humidity: The invisible pool party guest that can really dampen your spirits.
5. Wind Speed: The ultimate diva, blowing away your hard work with a gusty attitude.

Mix any of these factors, and you’ve got a recipe for a pool party disaster. But fear not, for every complication, we’ve got a comedic countermeasure:

• Decreased Set Time: It’s a race against the clock, so move faster than a teenager asked to do chores!
• Increased Drying Rate: Plaster’s drying out faster than jokes at a bad comedy show.
• Water Demand Spike: Your plaster is thirstier than a marathon runner in the desert.
• Cold Joints: Not the hip kind, but the kind that makes your pool finish frown.
• Discoloration: Like a bad tie-dye job, but on your pool.

Our trusty nomographs are like the weather forecast for evaporation—just with less chance of getting it wrong. And remember, when it comes to Plastic Shrinkage, wind is the big bad wolf trying to blow your house down.

So, how do we outsmart Mother Nature? Here’s our weatherproof plan:

• SSD (Surface Saturation Dry): Keep it as dry as a comedian’s wit.
• Control Hydration: Like a bartender for your plaster, mixing the perfect cocktail.
• Maintain Equipment: Treat it better than your car; it’s what gets you to the finish line.
• Increase Labor: More hands make lighter work and better punchlines.
• Weather Timing: Be the early bird or the cool cat in the shade.
• Reflective Gear: Shine bright like a diamond, or at least like a well-placed tarp.
• Tent It Up: Because every good project deserves its own circus tent.
• Chill with Materials: Literally. Use chilled water and slow-setting cement.
• Admixes & Pozzolans: They’re like the secret sauce to a gourmet meal.
• Water Reducers: Because sometimes less is more.

And there you have it, folks! With these tips, you’ll be the pool whisperer, taming the wild elements with a splash of humor. Until next time, keep your plaster happy and your pools smoother than a dolphin’s dive!

Remember, always refer to the manufacturer’s recommendations and the nomographs for the best results. Happy plastering!

 

Tech Bulletin - Plastic Shrinkage Temperature vs. Wind | NPC (nationalplastererscouncil.com)