Modified jointer cutter head

[wayne booker]

Hey all,

I've had this old Jet 6" jointer for over a year now and it's been working great. What's not so great is pulling and re-installing, adjusting the knives. To be honest, it sucks. My method is using a dial indicator on mag base and steel straight edge. What takes so long for me is the constant end to end check/adjust/re-check/re-adjust stuff on each knife. When you move one end of the knife, the other end is affected.

I bought a jointer pal jig. It made it easier to adjust the knives parallel to the out feed table, but then another issue was not resolved: The fact that I have to hold the cutter head by hand with the edge of the knife at top dead center while wrenching on the knife locking bar nuts. The constant rolling the cutter head back and forth to make sure I'm touching the jointer pal ends up blunting the knife in that spot a little bit. Not by much but I can tell by touch. Steel on a steel edge, which one will lose.

What I needed was a way to hold the cutter head in one place, the same place for each knife. I know that some guys will wedge a piece of wood in there to jam it in place, but there's just something about that that I hate.

What would be nice is if the jointer manufacturers included an index locking feature. I did some web searching and was not able to find anyone talking about such a thing. I don't know, maybe I'm just being a weenie and should just live with it, I thought.

After more thought I came up with this. I got ahold of a 1/4" pin from Ace Hardware. Then I located the right position to drill a 1/4" hole through the small bearing housing, and with the housing in the right orientation on the cutter head bearing, I continued that hole into the end of the cutter head about 1/4". Then I made a wooden jig that would allow me to drill the same hole in the same place in the cutter head next to each of the knife positions. The pictures are pretty self explanatory.

So with this, I set up my knives using the jointer pal in 5 minutes flat. I never had to make one re-adjustment, each knife went in with 0.001" accuracy end to end and from knife to knife. I didn't have to roll the cutter head back and forth scraping against the straight edge, the knife stayed in one spot while I tightened the lockdown nuts, and because each knife was held at exactly the same position in relation to the center of it's rotation, all three knives were at exactly the same height in relation to the out feed table.

Take what you want from this, but it's working quite well for me. I know many of you guys can do it the old way with one had behind your back while hopping on three toes. That's all well and good for someone who has the years experience to do it. I'd rather spend my time cutting wood. If I've peaked your interest here, I have a more thorough writeup with more pictures here: http://lumberjocks.com/ic3ss/blog/30122

Wayne

[Van Huskey]

Very cool. Lots of old iron jointers and planers had indexing heads, they had to have them since they were designed to be used with jointer/ginders which sharpened the blades in place. It is one of the ways the modern light weight machines save money.

You did a great job!

[Peter Quinn]

Excellent modification. I've struggled with the same issues. My solution was a BYRD HEAD in a bigger jointer. Solves the knife changing issue for good. I wonder why jointer makers haven't included a feature like yours, seems simple nought to include?

[Larry Edgerton]

Nice Mod! I use Esta's on one jointer and a Bryd on the other but what you are talking about is why I switched. Good thinking.

I don't believe I have a single machine that I have not modified to improve its function. Things can always be better.....

Larry

[David Kumm]

The old jointers had that modification and it worked very well, although the heads were balanced after they were drilled. That might be an issue with a larger heavier head. Dave

[Larry Edgerton]

I don't know if you change all of your knives at once, but I don't. So to keep track I have stamped the heads at each knife with 1-4 for example and under the hood write on a piece of painters tape what my last move was, for example "#3 new" or #2-4 turned. Each time I turn, shift or replace a knife I write it on the tape.

Even if you are sharpening you do not necessarily need to do all the knives at once as long as you are not taking off much weight. Saves time and money. For roughing out stock I will slip in some old knives and change them back when the stock is clean. What ever it takes to save a buck is money in my pocket.

Larry

[Bobby O'Neal]

Very cool idea and great execution.

[wayne booker]

I've run the jointer and I don't detect any more vibration than normal. I replaced both of the bearings a few weeks ago and it's running very smooth. Good point though.

Wayne

[J.R. Rutter]

Great modification. I used to have a Grizzly "ultimate" 8" jointer that came with an indexing pin that was spring loaded to pop into the hole as you rotated the head.