Blade Replacement 20" General Planer With Helical Head

[Daner Steel]

He all,
I picked up a used planer General#30-300-HC With the 2 sided carbide knifes.
I looked like to me that the previos owner ran some boards through full of nails
Almost all knifes were nicked and chipped.
Anyway I ordered 60 new blades and they only sent me 30(there mistake) 30 more on the way.

There were some of the blades chipped on both sides so I replaced them, but some I was able to flip over to the unused side and managed to get the whole cutter head with sharp blades.

Its now planeing the stock down good and fast but I'm getting about 5 groves that are cutting a bit deeper.
Any Idea what this could be?
Any help would be most appreciated

Thanks

Dan

[Mark Carlson]

I got this from the byrd site on how to replace the inserts. If you dont do it correctly you might get inserts at different heights.

When replacing or rotating inserts, the seat should be as clean
as possible. This will prevent breakage of inserts and ensure
proper insert alignment. To properly align the insert, press the
insert away from the seat while tightening to approximately 55
inch pounds torque. This allows the countersink in the tip and
the taper of the head on the flathead screw to slide the tip into
its proper position.

[Andy Pratt]

There's always the chance the replacements they sent are not the same dimension as what you are keeping on there from the original set, I would check that before anything else.

Second (most likely if the defects are minor) option is that they are not perfectly fitted in. I think the usual cause of this is sawdust/debris against the registration point when you put the new cutter in position. A tiny piece of sawdust/chips can throw the angle off a little which makes the leading edge gouge and cause what you are experiencing.

[Daner Steel]

Thanks guys.... I did check the size and there the same as the old knifes.
I did blow the sawdust out where the knife assembly goes.
There not off too much...I wonder if the old chipped knifes are not going in far enough.
If that's the case then any chipped knifes on this planer should be scraped not flipped.