This is an awesome project. Lots of fun and plenty of room to learn some more skills! It's a great entry-level project for beginner welders or those who already have plenty experience. Cost me around $80 in steel and free pallet wood. Turned out great! Enjoy!

***Please use every tool with caution and stay safe!***

Tools:

Welder
Welding Helmet
Welding Coat
Gloves
Grinder
Cut off wheel
Chop Saw (for metal)
Mitre Saw (for wood)
Screw gun/drill

Supplies:

4 x 46" pieces of 1" square tube steel
4 x 24" pieces of 1" square tube steel
4 x 15" pieces of 1" square tube steel
2 x 43" pieces of 2" x 1/8" flat bar steel
2 pallets disassembled
Screws

Step 1: Cut Your Steel

I got 10-foot pieces of 1" square tube, and 2" flat bar from my local metal supplier. Measure out your cuts so each piece is measured from tip to tip of 45-degree cuts. Your two rectangles you will build all have 45-degree cuts to keep it looking classy! The rest will be straight cuts. I used a grinder with a cut-off wheel (zippy cut) but then used a metal chop-saw to finish off the rest of my cuts (much easier).

Cut your pieces as follows:

4 x 46" pieces of 1" square tube steel - 45 DEGREE CUTS
4 x 24" pieces of 1" square tube steel - 45 DEGREE CUTS
4 x 15" pieces of 1" square tube steel - STRAIGHT CUTS
2 x 43" pieces of 2" x 1/8" flat bar steel - STRAIGHT CUTS

Make sure to clean off all your cuts with a grinder! Be careful!

Step 2: Weld First Rectangle

Assemble half of your square tube together so you have a rectangle. I advise working on a metal table that's smooth and level. Steel is not nearly as forgiving as wood in my opinion. I used magnet squares to keep everything square and flush.

Grab two 24" pieces and two 46" pieces
It should look like a rectangle
Tack weld in place so it allows a little movement before final welding
When all is square and your happy with it, weld all corners together
Clean up your welds using a grinder disc

Step 3: Weld Second Rectangle

Repeat the same steps as the first rectangle. This rectangle will become the top or bottom of your coffee table.

Grab the other two 24" pieces and two 46" pieces
It should look like a rectangle
Tack weld in place so it allows a little movement before final welding
When all is square and your happy with it, weld all corners together
Clean up your welds using a grinder disc

Both rectangles should be same sizes. If they are not, you can slightly adjust where the legs pieces are welded.

Step 4: Weld Wood Supports

The wood will run widthwise on the coffee table for this build. We need to create a bracket to support/mount the pallet wood. The two pieces of 43" flat bar will be those supports. They need to be welded lengthwise along one of your rectangles on the inside edge. This will be your top facing rectangle so choose the one you want. Place the pieces flat against the inside of your rectangle on your work surface. See photos/video for more info.

Flush against inside length of your rectangle
Tack weld in place
Flip over rectangle and weld thicker longer beads along the two pieces for strength
Clean up welds with grinder disc

Step 5: Weld Leg Pieces

Now you should have two rectangles. They need to be mounted together using your 15" pieces of 1" square tube. One on each corner flush to all sides to give that perfect square feeling that the square tube carries throughout the entire table.

Make sure the pieces are flush and square
Tack in place
Before final welds wait for the next step

Step 6: Weld Both Rectangles Together

Now it's taking shape! It's now time to weld both rectangles together using your leg supports. Get your second rectangle and place it on top of the legs you just tacked on. See the photos for an example.

Assemble first and second rectangles together using leg supports
Square and flush it all up
Tack weld in place
When everything is looking good, begin your final welds
Try and get nice weld lines for less cleanup! (easier said than done)
Clean your welds with a grinder disc and steel brush
To a final clean using a rag and Mineral Spirits (use gloves!)

Step 7: Prepare Pallet Wood

This is fairly straightforward. You will need to get a couple pallets (make sure you like the look of them and they aren't too beat up). Cut them along the inside of the pallet spines and remove using a hammer and crowbar.

Get at least 2 pallets
Cut the pallet along the inside edges of the outer two supports (spines)
Remove using a hammer and crowbar
Square off one edge on each piece for proper cuts/measurements
Cut pieces to 22" 1/8 (measure the inside of the top of your coffee table to make sure length of pallet pieces)
Lay them out on your metal frame to see what looks good
Sand them all down

Step 8: Drill Mounting Holes

Leave the wood in the placement you like and lift them one by one marking the centers on the flat bar supports.

Mark wood centers for drill holes
Use oil on the marks for lubrication for the drill
Drill away (using a drill press prior to welding this together would have been ideal)
Take your time as drilling metal is harder than wood!

Step 9: Paint & Stain

Spray paint your metal (I chose black)
I used extra fine steel wool to slightly rough up painted finish to give a nice rustic look
Apply Danish Oil to pallet wood (a stain of your choice will also work)

Step 10: Mount Pallet Wood to Metal Frame

Place your pallet wood how you'd like them mounted
Screw using short screws to minimize grinding later (you could also use ultrashort screws so it doesn't go through the wood at all)
Screw them in from underneath using the holes you pre-drilled
Grind any screw tips that came through the wood (I really liked the look of this for some reason)
I chose to scuff up my wood a little more with the grinder to blend everything in a little

Step 11: Finish It!

Apply polyurethane or a finish of your choice to the entire piece
I applied 2-3 coats on the coffee table (don't go too heavy on the finish! Thinner is better than thicker!)
LOOKS AWESOME
ENJOY!