fireplace corbels

[This is part of my FIREPLACE MANTEL-103 series.]

Don’t Worry, They are Very Easy to Make

Years ago, when I was first thinking about starting a diy molding site, I debated long and hard over whether or not I should include a project difficulty scale, like other diy sites have.

Ultimately I decided against it because none of my projects are very difficult, even the ones with so many layers of moldings around them. More layers of moldings rarely means more difficulty, just more time to complete.

And these triple pilasters make this point perfectly.

They may look complicated to build, but I assure you they are not.

Like most of my designs, all you need to do is build an mdf core, nice and square, and then wrap it with moldings.

I’ll take you through each step of building these highly detailed fireplace pilasters, with lots of pictures to help guide you.

The Middle Pilaster as Example

If you are like me, then you sometimes neglect reading through an entire how-to manual and just dive right into a project.

And if that applies to you, then do yourself the favor and at least look at the picture below, otherwise you could end up being slightly confused if you skip ahead.

free fireplace plans

The arrow in the image above is pointing to the only U-shaped pilaster core you’ll have to make — even though it looks like there are three stacked on top of each other.


Step 1: Cut MDF Blanks

When I cut my mdf “blanks,” as I like to call them, I leave them about 1/8″ wider than what the final width needs to be.

diy fireplace

That’s because they will need 45 degree bevels ripped along some of their edges, so not having too much material to take off helps create a more precise bevel.

So this is how I cut my bevels:

  1. Pass your blank through the table saw to make the first rough 45 degree angle. Leave a blade thickness or less for the second pass.
  2. Send you blank through the table saw again. If you’re happy with your bevel, then you’re done. If not, shave a little more off.

You will get a feel for this in no time at all. Make some practice runs with scrap material.

A Note About Table Saws

I don’t like to spend too much time talking about tools, since other websites cover them in such great detail already.

But for this project you’re going to need a good table saw, so I’d like to at least say this about my old Bosh contractor’s table saw…sniff, sniff, … I miss you!

I loved that saw so much.

You see, one hot day in Phoenix, Arizona, a battered and dirty Datsun pickup truck pulled up to my job site.

Out jumped a bunch of fellas (I didn’t catch their names), who, apparently, desperately needed a table saw that day. And so took mine.

So if you’re looking for an all-around great table saw for your molding projects — one with an excellent fence and strong arbor — give the Bosh a close look.

Step 2: Assemble the Core

This time I made one long blank and then cut it in half with my miter saw.

I don’t always do it this way, sometimes I make them individually.

The long pieces can be harder to assemble accurately because they are harder to hold in place while you’re gluing and nailing.

There’s no right or wrong here, whatever length you’re more comfortable working with is the one you should use.

do it yourself

I used Titebond woodworking glue on the mating beveled faces.

Step 3: Spackle & Sand

It’s a lot easier to prep the corners on your core while they are laying like this on your work bench than when the whole thing is assembled.

diy mdf

I use my trusty Porter Cable palm sander to get the job done.

palm sander

In no time at all, you’ll have a perfectly square pilaster core like the one pictured below.


And that, my friend, is all you have to do to build a build a pilaster core.

Posts in this Series

1. How to Build FIREPLACE MANTEL-103 for $333.08

2. How to Build FIREPLACE MANTEL-103 Part 2: Materials Inventory

3. How to Build FIREPLACE MANTEL-103 Part 3: Pilaster Cores

4. How to Build FIREPLACE MANTEL-103 Part 4: Corbels & Inset Panels

5. How to Build FIREPLACE MANTEL-103 Part 5: Shadow Pilasters

6. How to Build FIREPLACE MANTEL-103 Part 6: Wrapping the Crown Molding & Base

7. How to Build FIREPLACE MANTEL-103 Part 7: Pilaster Extensions

8. How to Build FIREPLACE MANTEL-103 Part 8: Lanterns

9. How to Build FIREPLACE MANTEL-103 Part 9: Lantern Crown & Collar

10. How to Build FIREPLACE MANTEL-103 Part 10: Paneled Frieze

11. How to Build FIREPLACE MANTEL-103 Part 11: Making the Hood

12. Before & After: Great Room Fireplace Mantel with Overmantel

13. How to Make OVERMANTEL-100 for About $87.39