I wanted to mount the TV above the fireplace but the heat rising up the outside of the chimney just gets too hot. I decided to make a mantelpiece to divert the heat away.
You will need:
4 lengths of wood (pine as it's the most commonly available in New Zealand)
2 corbels - these are the end supports
My chimney is 1.1m wide and conveniently the wood comes in 1.2m lengths. Exact measurements 1200mm x 100 x 12
The cables look pretty ugly - fear not though,, these will be tackled in another instructible.
Step 1: Cut Wood to Size
Stagger the 4 lengths of wood as shown - this will be the finished look from the front. I'll refer to the lengths as steps from now on. Staggering not only looks nice but also helps push heat away from the chimney.
Each step overlaps the next by 10mm at the front and sides so cut to size.
Then cut the back of all steps to the same depth so it they will sit flush against the wall. I cut mine individually but as you wish. When finished it should look like picture 2.
Step 2: Glue Stage 1
Just glue the bottom 3 steps at this stage. This is to avoid screw holes in the top - you'll see in a later step. Be generous with the PVA glue then clamp the pieces together while glue dries - yes I know the photo shows 4 pieces clamped.
Step 3: Choose Screws for the Corbels
Corbels are the supports - yes it was a new word for me too.
The corbels will be screwed to the steps so select screws long enough to pass through all 3 steps and into the corbel - again the photo shows 4 steps - sorry about that.
Step 4: Drill Holes Stage 1
At this stage we're working from underneath side of the mantel
Place the corbels in position and mark around them - you can just see the outline in picture 2
Now remove corbel and drill 3 holes inside your pencil outline. Drill the holes in from the edges.
Step 5: Drill Holes Stage 2
Now working from the top side of the mantel.
Place the corbel back in position and redrill the same 3 holes - this time drilling into the mantel itself
Then counter sink the holes.
If you're keen, you can combine drill stages 1 and 2 and just drill once through the steps and the corbel together. I did it in 2 steps as it was difficult to gauge positioning.
Step 6: Screw Corbels to Steps
Remember we're still working with 3 steps
Step 7: Attach Top Step - Glue Stage 2
The 4th and final step goes on now - this is the top ledge
Lots of glue and clamp it again while it dries. I've also stacked some heavy weight on top to ensure good contact.
Step 8: De-lamination Screws
I've called them de-lamination screws as that's exactly what they are. I thought this job was finished after the last step but I found that the heat from the fire caused the steps to bow. The glue let go and large gaps appeared between steps.
So, add extra screws and don't be shy.
Step 9: Trim to Allow for Poor Planning
The mantel and corbels was originally placed completely above the fire but it just didn't look right. The corbels need to hang lower unfortunately they wouldn't fit so I trimmed them. See before and after photos.