Horsepower, bad blade, wavy cuts question

[azmtnman]

I got wavy cuts with a new blade (new, not a resharp). My idle jet was partially clogged too. I cleaned the carb and changed blade and it cut fine.
   First question:
      Will resharp fix a blade that makes wavy cuts or do you toss them?

   Second question:
       It seems my old LT30 (20HP Onan) doesn't cut right when the idle jet gets clogged. It still runs decent at high speed but won't idle. My thinking is it can't be lack of HP because there are mills with 1/2 the HP from the mfg. I don't notice a lower blade speed.
   What do y'all think is going on with that? 

[SawyerTed]

If the blade that made the wavy cuts didn't hit any metal or get excessively hot Resharp should be able to sharpen.

Here are the first things I consider when I get a wavy cut.
Dull blade
Pitch build up on the blade 
Cutting too fast
Loose/slipping drive belt
Lower blade speed - could be from engine running slow

[SeaPickle]

I agree with SawerTed
Also check blade for levelness. It may have a bump/dish which is causing deflection. I commonly find these near the front 1/8 of the blade, often caused by overfeeding.
Is it tensioned correctly?
Tooth set even?
Too small of a gullet?

[esteadle]

>   Will resharp fix a blade that makes wavy cuts or do you toss them?

Yep, usually. But sharpen and set this blade. 

Get a magnifying glass and go outside in bright sunlight and look closely at these teeth. Look down on the teeth, along the width of the blade, and look at 3 teeth in a row, and make sure one is straight, one is swaged left, and one is swaged right. About 1/2 the blade width is where you should expect a new sharp, set blade to be. If they are not swaged out at least a little bit, the blade needs to be set. 

[barbender]

If your engine isn't maintaining a steady RPM you will not cut straight, either.

[kelLOGg]

Also check blade for levelness. It may have a bump/dish which is causing deflection. I commonly find these near the front 1/8 of the blade, often caused by overfeeding.

Is levelness the same as curvature?
Bob