Planer blade replacement question

[ed kerns]

I've just put new blades on my Delta 15" planer. I think this is just the 3rd time I have changed the blades out. The process seemed to go fine. I always have a bit of a struggle with knife height, but think I've got it zeroed in pretty well. I just ran a couple of test boards and I seem to be getting more tear out than normal. I also seem to have more chips sitting on the board than usual as it exits the machine. Nothing has changed with the dust collection. I understand all boards are different and maybe I just grabbed a couple of finicky pieces (to be honest one board was tiger maple, I just wanted to see how pristine sharp knives would cut it, but the other was minimumly figured maple). My question to you old hands is is there something I could be missing? I'm thinking about the chip breaker. I didn't pay much attention when I put it back on. As a bonus question, where do ya'll recommend to sharpen steel planer blades?

[fredhargis]

It will vary with how much would you're removing at a pass (the chip stuff), and if you're getting a smooth cut I wouldn't worry about it. As for a sharpener, I used Bull Sharpening in Oak park IL (they have a website with their prices).

[atgcpaul]

Is it possible that you installed them backwards?

[mike4244]

Try running another species thru and see if the results change.

mike

[ed kerns]

You know, I have to admit that the first thing I checked was to make sure the knives were in the right way - fortunately they were. I also tried planing some white oak, with about the same results. Not terrible mind you, just a little more tear out than I would like, especially with new edges. For what its worth, I swapped these blades because I found a nail (the hard way) buried in the last board I planed. At least the new boards don't show the tell tale blade nicks their full length.

[jasfrank]

Ed, can you slow the feed down? Or is it a single speed machine? Some figured woods and some woods due to MC don't plane worth a dang. A back bevel on your blades would cure the issue, but its not easy on the planer either.

[ed kerns]

Yes, I can and will slow the feed rate. The crux of the question though is why are these new blades not cutting as cleanly as the old blades. Specifically is there a mistake I may have made in the installation to cause the difference? Or, I suppose, might my having hit a nail with the old set of knives caused damage to the machine, other than the obvious nick in the cutting edge? I probably still haven't run enough lumber through the planer to say definitively that my results have suffered, but it's looking that way. One thing I didn't do is clean the oil off the new set of blades. I figured a board or two run through the machine would take care of that.

[jasfrank]

oil sure wouldn't cause problems. I have used kerosene to clean pitch with no issues. I doubt its your angle of grind but sure could be. In my experiences its been a moisture or grain problem.

[oakey]

Ed
there is a guy at marine city mi that I use for all my sharpening
does a nice job
called progressive tool co
his phone is 810 765 5030 he is just outside marine city
not sure if he ships I am not to far from there to take a drive when necessary
sam

[jteneyck]

Are you sure the angle on the new blades is correct. I once tried putting a micro bevel on my blades. It worked so well that the next time the blades needed to be sharpened I just extended the micro bevel. When I was done the micro bevel was nearly half the width of the cutting edge, and changed the attack angle from 45 deg to something a lot less. There wasn't enough clearance and the trailing edge of the micro bevel hit the wood, leaving broken compression scallops. I have one planer that has sharpening angle of 45 deg, the other 42 degrees. Maybe yours weren't sharpened correctly?

If you are using steel blades it's not hard to sharpen them yourself using the scarey sharp method or waterstones. All you need is to make a wooden jig to hold them at the correct angle.

John