To cut bigger pieces I bought the extension rails for my Mafell Erika table saw. There's also an extension table available, but it's very expensive. To save money I decided to build one my self.
Step 1: Dimensions
The exension table must fit into the V-groove of the extension rails. To get the correct dimensions, I take them directly from the rails.
Step 2: Cut Table to Size
The extension table is made of 18 mm resin coated plywood. Befor I cut through the wood I start with backwards scoring cut of about 1 mm to prevent tear out.
Step 3: Cut Grooves
To fit the table intot the V-gooves, I have to cut a groove on the smaller sides. The dimensions are taken from the extension rails with a calliper.
To make the alignment of the router easier, I'm cutting a spacer with the width of the groove.
Since the groove is 13 mm deep, I'm cutting it in two steps.
Step 4: Spacer
To align the top of the extension table with the table of the saw, a spacer is necessary. It also serves as reinforcement, since there are only 5 mm of plywood left on the sides.
I'm taking the dimensions of the spacers with a caliper.
The spacer is fastened with screws. This allows to remove it and add some layers of paper if its' not at the same hight as the table of the saw.
Step 5: Recess for Clamping Srews
I'm using an awl to mark where the clamping screws have to go. The recess is then drilled with a forstner bit.
Step 6: Finished
And this is it. I'm using the extension table very often. Actually I just leave it at the saw and use it to cut big pieces or just as an additional work table.
It's of course much cheaper than the original extension table. One feature I think is very handy, is the fact that it covers the full extension width. This prevents the fence from falling through as you can see im my kitchen shelf video.
The next project shows how to convert the extension table into a router table.