Bodgers":1k52lhve said:
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- I heard the pressed steel extension table wasn't up to much, but it is really bad. When I first got it out of the box, I thought "how bad could it be?". Pretty bad actually. The aluminium rails that it hangs on, and connects to the saw by, are perfectly fine and true. Problem is the actual pressed steel table - it is a joke. Basically the pressing near the edges push the corners up, resulting in a difference in height of around 10mm between the edges and the middle. There is also a support strip welded half way on the underside, which results in more unevenness. I am going to swap it out for some thick birch ply at some point.
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I don't quite understand in which direction your extension top is out of square, but 10mm is nuts! Is it possible your extension top is damaged? Might be worth asking Axminster about? After playing about with the levelling screws, my top is pretty good – though obviously not as flat as the cast iron.
One thing I noticed with the fence is that the source of the judder and movement seems to come from the tendency of the fence clamp nylon screw cap (if that makes sense?!) to ride against the fence rail. If you pull the fence clamp block back with your hand while you slide it, the judder seems to go away. This also stops the large lateral movement of the fence when tightening the clamp. So as you've done, packing it out is the right thing to do. I think I'll do the same but with some PTFE tape.