Box making

HI All

looking for some advise. I tried making a wooden box recently (simple you say) so i went about it by making the box using biscuits, glued and nailed a plywood top and bottom, then thought i could just slice through at the appropriate spot with the triton set in ripping mode,

Problem is that the saw as it touched the timber kicks slightly enough to make the cut through the box not exactly straight enough to make the lid sit nicely on the base.

What is the best way to do this or should i be using some sort of flat plate to find the hight points on both the base and lid and planing flat as possible?

Any advise would be appreciated

Adrian

You've done it the right way, but you need to make sure it's up firm against the fence when you cut it. Don't cut all the way through - leave about 0.5 mm that you cut throgh with a hand saw. Then remove the waste with a plane or pare it away with a sharp chisel.
If the cut isn't quite straight you can use a plane set fine to straighten them, or use spray-on craft adhesive to attach a bit of 240 grit sandpaper to a piece of flat laminate and use it to flatten both the lid and the base.