Circular Saw Base Grips the Timber

I recently bought a Renegade 1800W 185mm circular saw in Australia from Trade Tools.



I plan to use the saw for constructing stage speaker boxes from 12mm pine ply.

I was attracted to the saw because it was relatively cheap, but mainly because it had a magnesium cast base.



Before I started building my speakers, I used the saw to cut some Shadowclad, which is also 12mm pine, but is treated and has rough saw faces.

Right from the start, the saw needed considerable effort to push it through the ply sheet - as if the blade was blunt.:?

As I wasn't familiar with the saw, I didn't take too much notice. All up I probably did about 8 metres of cutting through 12mm ply.



When I went to start my main project (speakers), I changed the blade from a 24 tooth to a 40 tooth.

It was then that I noticed that the undersurface of the magnesium base was very rough (finely pitted).

This I now believe was why the saw appeared so hard to cut through the 12mm ply sheets.



What can I do to fix the problem?

I was thinking of coating the surface of the base with a silicone product - say car polish? Or maybe some sort of dry lubricant?

But should I try to smoothen the surface first?



I am a newbie to woodworking, so any help would be greatly appreciated.:)