rough surface with 747 blade

[postville]

I tried some 747 blades and got rough surfaces. LT40, 28 HP motor. I tried to vary the feed and checked the belt tension. Looks like blade was vibrating.
Material cut- poplar and basswood, 14 inch diameter.
I put on a Double Hard 10 degree,  1 1/4", 7/8 pitch, .042 blade and everything settled down.
It was suggested I don't have enough power, that the 747 blade is very aggressive.
Your thoughts?
Bob

[barbender]

Aggressive blade profiles like the 747 and 739 require a fast feed speed, or they make ripples.

[Magicman]

Looks like you do not have the HP/speed to empty those deep sawdust filled gullets.  

[postville]

Would sharpening to 10 degrees help?
Otherwise, anyone need some 747 blades?

[YellowHammer]

747's do like a fast feed, and will resonate in softer wood and slower speeds.

Here is a video that shows the effects of sawing speed on cut quality, and I'm using a 747 band, which I prefer.  Your cuts are illustrated at about 10 minutes in. 

Yes, you can reprofile the bands.

[jpassardi]

I have seen the same YH.
I'm now using some EWP for B&B siding that I milled before I upgraded from 15 HP to 25 HP. I'm running into some of them that had similar chatter (wider cuts so feed had to be slower). With 25HP and 737's I'm now able to feed fast enough where I haven't gotten chatter since. I have also used some leftover 747's I have with more HP and don't recall seeing chatter.