My PC is a 7518 so, I'm not sure speed settings are the same but, I cope at the 2nd from the highest speed.
You should have sandpaper on the backer block. Stop it before the cut, though. It'll dull your bit.
You can make a good sled with a piece of 1/4" hardboard and some scraps of 3/4 hardwood and two De Staco clamps. It's no biggie to build, it's dirt cheap and it works great.
If you are interested, I'll post a pic of my sled. It's not hardboard, but you'll get the idea.
'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton
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