Best way to replace planer knives

[Tom Jones III]

I was certain this topic would be beat to death already so I did a search ... not much came up. I'm trying to replace the knives in my Jet 13" planer for only the second time. The first time was a nightmare. The second time is traveling the same route.

Attempt #1: A local ww'ing store sold me 1 planer pal and said that 1 would be enough for my 13" planer. It seems to need 2, because the single one acts like a pivot point. A test run produced a wave pattern.

Attempt #2: I tried using my dial indicator to set the left side to all the same height. I then repeated the process on the right side. A test run produced a wave pattern.

Attempt #3: I tried using my dial indicator to set the left side to .075 above the cutter head. I then repeated the process on the right side. A test run produced a wave pattern.

So, what method do you use to set your knives? I'm trying to decide if I should pick up a second planer pal on my way home from work this afternoon, or if I should save the money and try something else.

[Travis Porter]

I have a Grizzly 1021 and it came with a knife setting jig. I know there are jigs out there that make it easier and will hold the knives in place across the entire length.

[Dennis McDonaugh]

You need two planer pals to work properly, but I find the jig supplied with the machine actually works better anyway.

[Sam Chambers]

Tom:

I use a pair of Mini Planer Pals in my 12" Delta planer, and they work great. Best little jig I ever bought.

Now the Jointer Pals I bought are a whole different story. Sure, they hold the knife in place, but mine aren't accurate. It's a sound idea though. I'm thinking about getting a few rare earth magnets and making my own version.

[Neil Bosdet]

I built a jig that straddles the cutter assembly, resting on the spindle. Through the middle of this I drilled a hole and mounted a dial indicator. I slide this from one side of the knife to the other adjusting until they are exact. I use the same adjustment for the other knives. I works well and provides decent results but is not the quickest in the world. I too, am wanting to make my own with rare earth magnets. My only concern would be how to get them identical (within say .002" of each other)?

[tod evans]

neil, build your jig out of aluminum and drill and tap 1/4-28 holes. the magnets will stick to the 1/4" bolts to allow adjustment. .02 tod

[Neil Bosdet]

Great idea!!! Thanks.

[John Miliunas]

Tom, I've got a magnetic set (pair) from Woodcraft, which I use to do my 15" planer. They were only $50.00 for the pair and work great.

But, that doesn't help your situation. As long as you have one Planer Pal and the dial indicator, how about trying this: Before proceeding with using your dial indicator, make sure the surface you're mounting to is truly parallel to your cutter head. Zero it out on one side (just on the head, not a knife) and go to the opposite side and see if it matches. If not, you need to find a way to index off the head itself. If you can't, forget the rest of what I've written below!

Loosen up the jack screws to allow the blade to slide up/down. Put the PP on one side and take your dial indicator measurement as close as you can to the PP and note it. Now reposition your indicator on the opposite side and adjust the jack screw to match your noted measurement. At this point, I'd go over to the PP side and put the indicator back on it and snug up the jack screw on that side, as well. Tighten everything down.

[CPeter James]

What idiot sold you ONE Planner Pal? They obviously know nothing about woodworking machinery. Find a store that does have some knowledgeable help. I had a set of the mini planer pals that I used on a 12" bench top planer. They were great. On my Jet 15" I use the jig that came with it. It works fine. I made jig to hold the supplied jig in place as I only have two hands and a third would have been handy. Lacking that, get the mate to your planer pal if in fact it will work on our planner.

CPeter