How easy to knick jointer knives?
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Just got my first less-than-perfect surface from my jointer knives. It appears there’s a very, very tiny knick in one (or more?) of them that’s producing a tiny raised line on the surface of the wood. Straight as an arrow.
I’ve run nothing but very clean wood, and not much of that, over this new jointer. Is it super-easy for these knives to get tiny knicks in them? Or did I pick up a piece of grit somewhere I didn’t know about.
forestgirl — you can take the girl out of the forest, but you can’t take the forest out of the girl 😉
Replies
Jamie: Doesnt that PYO?? I have had this happen to me a few times, once or twice right after I had them freshly sharpened and remounted in my jointer, could be grit or they hit a very hard knots or hard wood?? you sure there wasnt something imbeded in the wood you didnt notice??
ToolDoc
This was S4S oak stock that I bought long before I had the machinery to do it myself -- I was getting it nice 'n flat. S'pose it's possible I picked up a bit of grit somewhere. Would hope that there wouldn't be anything (short of a knot) in the oak itself that would do such a thing. Will take Sgian's advice and move the knives if it bugs me too much. Small enough blemish that it can be taken out with sanding.
How many linear feet of oak (face-jointing) does it take to dull my knives? Have to confess, I'm dreading that first knife-change experience. Spun the planer blades around tonight -- that's a piece of cake of course. Except for the Delta gorilla that installed them -- there was one screw in each blade holder that was put in with twice as many ft-lbs of torque than the others. Actually had to get an extender to put on the huge allen wrench they provide to loosen up one of them. Got a few sparks off of it as it came loose. Sheesh! The same gorilla helped put together my Delta drill press -- took a 2-foot pipe extension on the goodly-sized closed-end wrench to get the bolt to the table loosened up so I could tilt it to 5 degrees. Must be the great-grandson of the Samsonite simian.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
FG,
Same, same here with the very first board I nicked my planer knives. Altough in my case there was no riddle, the nail shined brightly after going through the planer....also had the same screw removal issues when I did turn my blades around.
What confuses me is what is the difference between changing the knives and spinning the blades around? As you said spinning is a piece of cake. When I bought the planer people said how tricky it was to change the knives...but having turned the blades once already, I can't figure out the issues I'll confront when I change the knives. Am I missing something here?
Assuming you have the Delta 22-560, we don't have the flexibility to shift our blades or get re-sharpened..what ever nicked your blade probably did it to both in the same place. I continued to use the nicked blade for some time hitting the high spot with a hand plane afterwards....I can still see the line in every piece I worked with those blades...no one else notices, but I do
Edited 10/4/2002 5:46:30 AM ET by BG
Hi BG. Those horror stories about changing blades in a planer relate to planers that do not have the quick-change, indexed knives like we have. Our blades sit on little pins that keep them the exact correct distance from the cutterhead. Older planers had to be set the way jointer knives do.
Actually, I believe you can shift them a bit to compensate for knicks. Just loosen all the set screws and jig one blade to the right and one blade to the left. There is just a tiny bit of play right-to-left in the knives, probably just for that purpose.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Edited 10/4/2002 11:46:39 AM ET by forest_girl
Jamie: Delta Gorilla?? I dont know if they have them, But did I tell you the Delta Girls are cute!! <G>
ToolDoc
FG, Grit, wee nail, lead shot, knot, etc., might all nick a blade. If it's bothersome to you, slacken the gibs, and slide all the blades left and right a bit to offset the nick in each one, about 2 mm each way should do it and retighten the gibs, thus moving the nicks in the blade away from each other resulting in a flat surface, until the next nail, etc.. Alternatively, just run a smoothing plane over the ridge in the timber if it's severe prior to thicknessing. Slainte, RJ.
FG:
A newly ground knife or blade will sometimes have a small burr left from the grinder. If this is not removed, it could cause the micro nick that you describe. My jointer and planer knives have to be set the old fashioned way.
After installing newly sharpened blades,I always rub the edges with a fine hone.Sometimes the burr is hard to see but can easily be felt with the fingernail.FWIW¬¬¬¬¬¬¬¬¬¬¬PAT¬¬¬¬¬¬¬¬¬¬¬
"Sometimes the burr can be hard to see" -- tell me about it! Sheesh, this middle-aged can't-see-in-front-of-my-nose thing is a real pain!
Thanks for the tip. I'll check any new blades as I'm installing.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
All wood here is sold rough sawn. About 10 years ago we had trouble with wood coming out of Slovinia and Croatia, oak mostly . the problem was bullets. You would not believe what that does to jointer and planer knives. I got into the habit of keeping an old (knicked) set around and installing them to do the first cuts. Thus all "grit" is removed, you can see if there are and suspisous holes and the finish knives smooth the boards perfectly once installed. Fine you loose a bit of time changing knives but in the long run it pays off.
Philip
Those boards have been on the ground, on other boards, in your truck, and are most likely dirty! Clean them with a wire brush before jointing or planing. A woodworker that writes for Fine Woodworking recently explained this to me.
It doesn't take much you know. A piece of dirt or grit from the floor would nick your blade for sure. Maybe even something in the wood like a nasty knot or errant piece of metal, staple, etc. Bummer.
Welllllll, my shop is already cleaner than my house (which isn't saying much, truth be told). I'll keep a pair of white gloves around to check before I mill, LOL.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I'm a bit confused about whether you're worried about Jointer or Planer knives... As I recall you have the same 6" jointer that I have...I too was very reticent to change these..would I get it right, etc, etc. I bought one of the metal "Planer Pals" at Woodcraft and it couldn't have turned out better. It was SOOOOO easy...even I can do it (smile).
I have no experience in changing the blades on my planer (yet...).
Good luck Forect Girl!
lp
Jointer blades, as stated in discussion title. We did get a little off-track in the thread :-) but then again, what are threads for?? We shall weave a tapestry, LOL.
The planer's a snap, of course, with the quick index knives. Anyone know why they don't do something similar with jointers? Thanks for the 1st-hand recommendation on the "Pals" -- I've wondered how well they work.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Hardy har har.
Forrest Girl fuuunnnny. I've got so many of those darned nicks on my planer blade that the boards exiting the planer look like an honest man taking a polygraph test. Even when I change out the blades, its just a matter of time, usually hours or minutes, until the fresh new blade is nicked. Sure, I plane ultra thin portions at a time, but alas to no avail. I guess thats what red oak will do. I end up having to sand those lines down until they disappear. There have been a few that I have missed with the sander, only to leap out in utter anguish when that first coat of stain goes on. Nicks bad. Smooth good.
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