The Technical Side of Primer — Resins, Stain-Blocking Chemistry & What Really Creates a Durable Finish

If you’ve ever wanted to peek under the hood of primer and understand exactly what makes it perform the way it does, Episode 20 is your grand finale. Val breaks down the technical side of primer — from resin types and solvent behavior to stain-blocking chemistry and why certain formulas outperform others on specific surfaces.

You’ll learn what’s happening at a molecular level (yes, really), why some primers grip like a dream while others fail, and how these details impact your sanding, painting, curing, and long-term durability. Even experienced flippers will walk away saying, “Okay… I did not know that.”

And since this episode covers more science than your average paint aisle conversation, the Primer Power Workbook includes simplified notes and diagrams to make everything easy to revisit later. Print it out, keep it nearby, and impress people by casually throwing around words like “resin structure.” 😉 Grab your workbook here: ValFrania.com/PrimerWorkbook

Ep20 Advanced Primer Skills Every Furniture Artist Should Know

Val Frania

Hi friends. Welcome back to Flipping Furniture for Profit. This is Val Frania, and today we've arrived at the finale of the Primer Power Series. I've learned a lot just in the research I've done, so I hope this has been a great benefit to you. I was going to do a Beginner Mistakes episode at the end like I originally planned, but I'm not going to do that. This one turned into something so much bigger and honestly, much better. This is the Advanced Primer episode, the "Okay, you're really doing this now," episode where we take everything you've learned so far and elevate it.

Today we're going to talk about how primer actually behaves chemically, what ruins a primer, and what makes a primer fail, how to know when the primer is too old. Spraying versus brushing at an advanced level. Compatibility rules nobody ever tells beginners, tannins, wood structure and why some woods fight back, cure time mistakes, safety, VOCs and respirator, reminders. And yes, that goober filled story of the spoiled primer that I opened once. By the end of the episode, you won't just be using primer, you'll understand primer. And that's what separates hobby painters from true furniture artists. So let's dive in. Primer doesn't just sit on wood. It interacts with it. Most beginners think primer is just the first coat of paint, but advanced flippers know better.

Primer is chemistry, primer is engineering. Primer is the foundation that makes everything else work. Primers designed to grip and seal and block tannins. It fills pores, creates microscopic tooth, it stabilizes surface tension, regulates absorption, and bonds to slick surfaces. And here's the part most people never learn. Primer isn't just on the wood. It bonds into the wood. Wood is full of little capillaries. Tiny tubes and tannins travel through those tubes like water moving through a straw. Primers job is to fill and seal those tubes so nothing can sneak back out.

Here's a picture of another God's creations that helps this make sense. And once you hear it, you're not going to forget it. Did you know that polar bear fur isn't actually white? Each hair is really a tiny hollow tube. Those tubes reflect light, trap heat and help the bear survive in the cold. Wood is designed the same way. Beneath that smooth surface are millions of microscopic tubes, capillaries, and tannins travel through those tubes like little commuters at rush hour.

Now imagine painting over that wood with water based paint. The moisture wakes those tannins up and then they start moving. They ride right through those tiny tubes and rise to the surface like, "Oh, the highway's open. Let's go. Let's bleed through." It's not you. It's the wood doing what God designed it to do. And here's where primer steps in. Especially shellac or oil based primer doesn't just sit on top of the wood, it fills those tiny tubes. It's like closing all the highways so nothing can travel upward. Once the tubes are sealed, the tannins have nowhere to go. They stay put.

I love how even this tiny detail reflects God's creativity, Whether it's a polar bear fur designed to protect or wood grain designed to move nutrients through a tree. And in our work as furniture artists, understanding how he designed these materials helps us steward them well and create finishes that actually last. So the short version, polar bear fur and wood have something in common. They're full of tiny tubes, and primer's job is to fill those tubes so your paint stays beautiful, solid and frustration free. So primer is the seal that says, "No more moving around. Everyone stay where you belong." Just like the polar bears insulation works because the tube is sealed. Your paint job works because primer seals the wood's internal structure. That's why stain blocking primers are so powerful, and why sanding them too aggressively will break the seal.

So if you understand the personality of a wood, you'll understand exactly what primer it needs. Open grain woods like oak and mahogany have deep pores, strong tannins and texture that loves to telegraph through paint. Closed grain woods like maple, poplar, birch, they're smoother, have fewer tannins, are easier to paint. The soft woods like pine and cedar have knots filled with sap. The warm undertones will bleed through everything unless sealed properly. Tannins are hydrophilic. They love moisture. So when you paint with water based paint, tannins will say, "Oh yay, water! Let's rise to the surface." And that's why we see yellow and pink spots.

Primers job is to say, "Nope, stay where you are." So now let's talk primer compatibility rules, the ones nobody teaches beginners, and we're advanced furniture artists get the edge. Don't put shellac over uncured latex. The alcohol softens the paint underneath. Don't put oil primer over damp wood. Moisture plus oil equals peeling later. Don't put water based paint over glossy shellac without a quick scuff. It needs a little tooth. Don't mix water based and alcohol based products without respecting dry times. Different expansion contraction rates equals trouble and do test on the back first tiny two inch patch will save hours of heartbreak and do follow recoat times like gospel. Those instructions aren't suggestions or chemistry.

Now just a few quick reminders for you. I keep beating this drum. VOCs, masks and advanced safety. This is where we drop being casual and start being smart. Shellac based primer has strong alcohol fumes and high VOCs, so you'll need protection for your lungs. It's extremely flammable, too, so be careful. Don't use near any flame. Oil based primer requires mineral spirits for cleanup. The odor lingers, and since it's slow drying, gloves and ventilation is a must. Water based primer has the lowest VOCs and is easy cleanup, but it's the weakest stain blocker. If you can smell it strongly, your lungs are absorbing it. A good mask isn't optional, it stewardship of the body God gave you.

And do be aware that primer has shelf life. Yes, primer ages. And yes, old primer fails even when you did everything right. Signs it's going bad. You'll find a gritty or rubbery texture. It won't mix well due to separation. You'll see discoloration and a sour, nasty off smell. And the worst of it all. Goobers. I hate paint goobers. One day I opened a can of primer that had floating chunks and rubbery blobs. I had to strain the entire thing. And yes, there's a video proof for my Blueprint members. I decided to strain it because nothing else was off. It mixed okay. It didn't stink up to high heaven. It just had the paint goobers, so I was able to get those out by straining it into a glass jar. But if primer looks or smells wrong, don't use it. Unpredictable primer gives unpredictable results.

And as far as sanding primer, you don't sand primer for adhesion, only for smoothness. So a light scuff is plenty aggressive. Sanding breaks the stain blocking seal, especially with shellac. And here's the advanced rule for your scratch test if you decide to do one. Don't scratch test early. Cure Time matters. Primer gets twenty four hours. Paint gets twenty four to forty eight. And always test the back, not the front. Early scratches prove nothing except impatience. And as we wrap up the series, I want to leave you with a principle that guides my own work. Proverbs twenty two: twenty nine, "Seest thou a man diligent in business? He shall stand before kings." Primer is the unseen step. Customers don't watch you do it. They don't applaud you. If you do it, they don't even know you do it. But you know, it's diligence. It's integrity. It's the hidden work that honors God. And just like the Holy Spirit works in the unseen places in our hearts that perhaps other people will never know about, primer works in the unseen places of our efforts to create beautiful, functional art for our clients. The unseen work shapes the visible result.

In conclusion, you've reached a new level of mastery. If you're still here at the end of the episode, at the end of this series, I want you to hear something. Most people never make it this far. Most people never invest this deeply in their craft. They don't even care about the details. And most furniture painters never learn what you now know. You've just completed an advanced training on primer. The kind of knowledge that separates hobby painters from true furniture artists. You didn't just stick around for the pretty parts of flipping. You sat through the science, the chemistry, the troubleshooting, the unseen parts, the quiet work, the work that actually makes pieces last. And that tells me something important about you. You care about excellence. You want to serve your buyers well. You want your work to reflect integrity and craftsmanship. And you're willing to learn the details most people skip. These qualities, they make you dangerous in the best possible way.

You now understand what anatomy, tannin behavior, compatibility rules, adhesion science, cure times, safety, troubleshooting, and even how to spot a can of primer that has given up the ghost. This knowledge changes everything about the quality of your work. It elevates you. It sets you apart. It gives you tools other people don't even know exist. And I want you to know this is just the beginning. If you are the kind of person that wants to keep growing, If you want hands on support, behind the scenes demonstrations, deep dive lessons, and a community that believes in learning the art and the heart of flipping, you're always welcome inside Furniture Flipping Blueprint. It's where I pour the rest of what I know. It's where all the advanced techniques live. It's where beginners become confident artists and confident artists become professionals. And before you go, make sure you grab your free Primer Power Workbook at ValFrania.com/ Primer Workbook. It's the perfect companion to everything we've covered in this series. And thanks for joining me for leaning in, learning hard things, and showing up with a desire to do beautiful work that lasts. Now go create something stunning, something you can be proud of. Something that was primed with excellence. And I'll see you next week.