Let's talk skilsaw/ portable circular saw issues

If the factory shoe is not parallel to the blade , no way will the cut be accurate , period . If the bearings are worn in the saw , same result . I use a 7 1/4" worm drive Skil with a metal shoe . To make a saw guide : cut 2 pieces of 3/4" plywood (not chipboard) 1 @ 8" and one @ 6" . Fasten them together with an offset a little more than the offset from the shoe to the blade . Run the saw down the offset . The jig is complete except for clamps of your choice . Hope this helps .