My 735 planer put a continuous crown on some 35" long pieces I put through it.

The pieces were on a sloped sled, to taper them. The sled is flat and the wood was secured so it couldn't move around during the milling. It's been a few years since I last used this sled. Back then I got flat sides from the planing.

I bought the planer new in 2011, and it has seen moderate use. The blades are about 6 months old.

Could this be due to wear on the rollers? If so are they easy to replace? Or is there another reason for the crowning?

I have not run test pieces through the planer since this happened - it was last night. I'll do that today. I haven't noticed this issue before.

This photo is of about 2/3 of a board with a straight edge that shows the crowning.

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