If you weld on a regular basis then you may consider purchasing a welding table, but these can be very expensive. As you're already a skilled welder you can actually make your very own table at a fraction of the cost.
Making a welding table by yourself isn't half as difficult as you might imagine and as long as you have the right tools and materials you shouldn't find this very difficult at all.
Step 1 - Making the Frame
The first step is to make the frame for your table, it's very important that this is done correctly as will affect the success of the whole project. Cut four pieces of the square box section at 45 degree angle to make a rectangle the size you want for the table. Use your magnetic clamps to keep everything in place and put the frame on a flat surface a concrete floor will be a good enough surface to work on.
Weld the frame and continue cutting pieces until the basic frame is competed. It's a good idea to have a slightly larger frame than the piece of metal that you will use so that there are no sharp edges. If you're making a large table then you will probably want to include an additional cross-member to offer support and rigidity.
When you are making the frame you need to ensure everything is square. Measure the diagonals to check that everything is in square.
Step 2 - Feet
Whether or not you want to fit adjustable feet is up to you. If the table is being positioned in one place and will never be moved then you don't actually need adjustable feet. Adjustable feet will make levelling the table much easier once it is finished.
Adjustable feet can be purchased easily and often come with inserts which fix inside of the box section to make the task much simpler. The inserts are simply tapped inside the steel box section and then the feet can be screwed in.
Step 3 - Welding
The next thing you need to do is weld the top of the table onto the frame. This will be very easy and is normally done using a tack weld every few inches. If there are any protruding welds then these can be ground down using your angle grinder so that they don't cause any inconvenience.
If you want to store a gas bottle on the shelf under the table then you will also need to weld in additional support to make sure the bottle is secure and won't move anywhere. Using a chain should be enough to secure the chain and stopping it from being dangerous.
Step 4 - Leveling
Once you have finished making the table you then need to decide where to put it and use the adjustable feet to level it. Use a spirit level to check that the table is level and is a good surface for welding.