Oliver # 299 Planer ITCH Head Grinding
Updated: Oct 15
Let me start by saying I get asked a lot about this procedure. I have wanted to post something about this for a long time to help people figure this out, this procedure can be daunting. I have gotten a lot of calls from shop teachers that get a job in a shop with one of these planers, and have no idea how to handle it, and they find me on the internet. God bless shop teachers, right? So the situation I am in is this; I have a new to me planer (hope you saw my post on the restoration), and the grinder I have I have not used and did not start life with this planer. So let me say right now that after you do this once, it will be 100 times easier than the way I'm starting out, especially if you are sharpening your own planer. I also want to add that these are awesome planers and it will be worth it to you! The first thing I am going to do is check the grinding bridge for parallel with the cutter head. This is an easy step. Here's a couple pics of that;
This is a really easy step because mine is within a thou and that's close enough! Next lets get the grinder out. This stuff is expensive and I made a dovetailed box to keep it all in.
Unfortunately the grinder cannot stay on the planer so that's why they are often separated. Someone gives these parts a quizzical look before tossing them in the dumpster. So the grinder motor and diamond wheel is first. The studs in my grinder carriage were not rock solid so I used some stuff to lock them in. Heres a couple of pics;
Now the grinder can mount on two studs with hex nuts;
Make sure your wheel is tight. The motor and wheel are CW rotation and the little wheel shaft is right hand threaded, and it will loosen up on you. On this one there is a button head set screw on the backside I was able to hold with an allen wrench while applying some good torque to the wheel nut. The next step is where some black magic comes in; I'm not sure how to put this all into language but here goes. The part is the arm bracket and what I call the "duckfoot" tooth guide. Here it is;
This part has several adjustments that are all important. It mounts to the carriage with 2 hex bolts. The height of this is not affected by the adjustment dial that lowers the wheel. You need to get this as close to the cutter head as possible without touching it. That height is adjusted by the 2 little set screws in the recess. Once I have these adjusted, when I remove them from the carriage in one piece to be as repeatable as possible. This time I went one step further and removed the cast piece with it as shown in the top middle pic above. I did have to cut some off the bottom of my bracket to allow me the get the cap head screws out of that cast piece without taking everything apart. The lateral movement of the bracket on the cast piece is important because that is how you will be able to remove the "baseball outfield mowing lines" on your cut. Wow I hope that makes sense cause we got more! The duckfoot movement forward and backward changes the actual grind angle on each tooth. Make sure you have some negative relief on the back of the bevel. So once you set all this you should not have to do any of this again. Yay! Another thing I do is mark the rows of teeth on the cutterhead on the motor side, to help me keep up with where I am at. I stamp them but you could use a sharpie. There are 6 rows of 14 teeth for a total of 84. If you don't have to change any teeth we can proceed to grinding. If you do lets circle back on that. Without starting the grinder I do some dry runs on row 1 tooth 1 to see that everything is working. That dial adjustment knob on top probably has some backlash in it so it is good to get it close now.
These grinders are not meant to remove a lot of material; they won't do it even if you try. Once you get started you are going to be taking off .001", a thou, off every pass. The system I use is to grind the whole head then lower .001 and grind again. In my situation now I have ground 5 passes on 2 different days. This was unusual because the teeth on left side were a lot lower than right. I suppose that was because some dudes used the same side of the 24" planer over and over. I will never know but the point is to take your time. About 3 passes is all my attention span can handle at once! But keep in mind when I go back to resharpen this it will probably be 1 pass and I can usually do that in 30 minutes, start to finish. Most of that time is getting everything out and putting everything back. Before starting to grind there is a good trick for the lateral position of the duckfoot to the diamond wheel. The left side of the wheel should align with the "point" of the duckfoot, when looking straight down on it. Below is a drawing of what I am trying to say;
Getting setup from scratch is a lot of work. But after that these are so cool! I love my planer because it is so quiet and smooth and lovable! Alright here is a short video of my grinding technique:
Rinse and repeat 84 times. You have to put pressure on the cutterhead, with one hand, to keep the tooth and duckfoot in contact with each other. As you crank the grinder across, with your other hand, the cutterhead is turning slightly. This does take a fair amount of hand and eye coordination and is another skill to acquire.
Here is a late arrival;
Next time I grind this I will have a spanky new "Wedding Cake" from Staitoplane.com! These are so nice they are made from aluminum billet. The old ones were made from blue cheese....
Thanks for looking, hope this helps yall to a better Oliver life!
Life is short, enjoy your projects!