Having just bought my first jointer,I’m a bit confused about setting the height of the cutters in relation to the outfeed table. I’ve read that it can make a big difference as to whether the edgecut will be convex,concave or straight. some say the cutters should be even with the outfeed table,others say .002 above,and others say it’s a thing that varies from jointer to jointer. I need some help!
Thanks Anselme
Replies
my jointer manual called for the outfeed table to be even with the top of blades.
this allows the cut surface to ride directly onto the table.
I think, the cutters should be even with the outfeed. The infeed one should be a bit lower and planar with the outfeed.
If the piece you are jointing is bent, you should first approach the concave face, and if the bend is really pronounced, probably a slight pass only to the tail and the head of the piece would ease the next whole passes.
Alastar Moody
I'll pass along a tip from John White, manager of the FWW shop, that has worked for me. Once you're sure the knives are all the same height above the cutterhead, and even with the outfeed table, lower the table just a tad. Then edge joint two boards that are straight-grained and 2 to 3 feet long. When you're done with the 2 edges, place them together ("kissing" as it were). There will probably be gaps, snipe or both. Gradually, verrrry gradually, raise the outfeed table and joint until the 2 surfaces meet perfectly in a "gap-free joint." He cautions to always finish with a raising motion of the table, not lowering.
I set my blades the other day using this approach, and then face-jointed a 6" wide maple board, 3' long. It was a beautiful sight to behold. Another tip: a straight-edge is your best friend! I bought the 38" model on this page from Lee Valley, very reasonably priced and accurate to .003" over the length.
John has some very handy jigs and lots of good information in his book Care and Repair of Shop Machines, including shop-made magnetic set-up jigs for the jointer.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
This is a very tip if the jointer has an adjustable outfeed table. Some jointers don't have that feature and then you're stuck with trying to adjust each knife to the height of the outfeed table. Some woodworkers feel that the wood compresses a tiny bit as it passes over the cutter knives, hence the 0.003" elevated height of the knives. Please note that this comes from print, not my heads.
I always think back to a post by Richard Jones when this topic comes up. I've lost the bookmark, but IIRC his opinion (and he has boatloads of experience) is that different woods react differently to the knives and the best setting may vary from one wood to the other. Hopefully, if I mis-remember or misinterpreted, he'll jump in here and give me a good slap upside the head.
I know mine are set a fraction of a smidge above the table, but didn't measure it. I just did John's test and called it good. The piece of maple I face jointed afterward was slighly cupped to begin with and came off quite flat after 2 passes. Significant improvement over the way it was behaving before that. :-oforestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
No slaps fg, but your memory is correct. I have said that in the past, and it's still true. Ttimbers vary a little bit in their reaction to the knives entering the wood and scooping a chip out. There's a certain amount of hammering going on as each knife enters the wood-- it's not all just a clean cut.
Blunt knives impart a greater hammering action than do sharp knives and the wood will spring back a little. Also springy timber (or two examples of the same species, one wet and one dry) will spring back after being compressed by the knives.
Generally there's not much in it, but sometimes a slight adjustment of the outfeed table is in order to compensate for blunting or particularly springy timber. Slainte.Richard Jones Furniture
An easy way to check your set up is to make a partial cut. Just cut into a straight board, on edge, a few inches. Stop the machine and look at the contact the board makes on both tables. There should be exact contact on both. If there is a space on the outfeed side, your knives are too high and/or the table is too low. You can make it complicated with all kinds of special tools, theories and tests but the cut is the bottom line. Either you have it or you don't.
Beat it to fit / Paint it to match
A jointer does not create a flat surface. It is more of a washboard, a series of little scooped out troughs parallel to each other. There is a crest between troughs. The board rides on these crests when pressed against the outfeed table. If the table & knives are in exactly the same plane, the board would need to ride on the bottom of the troughs, not on the crests, which is an impossibility. Therefore, the out feed table must be slightly lower than the knives. How much lower depends on the rate of feed, so keeping your feed rate consistent is also important.
Forestgirl describes a good technique for adjustable outfeed tables. I used jointers with non-adjustable outfeed tables until about a year ago. If that is your case, adjust knives above the table until they engage a flat stick or something similar lying on the outfeed table but overhanging the cutters. While rotating the cutter head, adjust the knife height to touch the stick just enough to move it about 1/8 inch fore or aft. That is about as close as you can make an adjustment without going crazy anyway. BTW, this is an adjustment that must be made WITH adjustable outfeed table BEFORE adjusting it to the knives.
Cadiddlehopper
Well, Clem, you are the FIRST person to explain this in a way that I understand. It always defied logic to me to set the outfeed lower, but now I understand why. Then three posts later gbNUMBER says it again... THANKS guys. :)My goal is for my work to outlast me. Expect my joinery to get simpler as time goes by.
Wow!!! That makes me feel so necessary!! Thanxx!!Cadiddlehopper
Cadid,
As a result of this thread, I went down to the basement to play with my old old old Craftsman jointer which does not have an adjustable outfeed table. The old handbook says to adjust the cutters .003 higher than the outfeed table. This is about the height that moves a flat board about 1/8" as a cutter passes. It does work better at this setting than either a higher setting or keeping the cutters even with the outfeed table. It is also consistent with what others have reported in this thread.
Mel
Measure your output in smiles per board foot.
Glad to help. It isn't a method which I originated. A writer for FWW described that same procedure a few issues back also. Usually I don't have to adjust the outfeed table after setting the blades that way. BTW, I purchased 2 jointers such as yours, one about 1967, another about 1978. Both had outfeed tables with a hump in the middle which made them impossible to use. Fortunately for me, at that time Sears would return your money quite pleasantly.Cadiddlehopper
Caddidlehopper,
Your Sears jointers had hills. Mine has a slight valley in the middle of the infeed and outfeed tables. I believe it would be good to move up. Any recommendations in the 6" category -- either of what to look at or what to avoid? I was watching one of those idiotic Kung Fu movies the other day and heard the "Master" utter a great line that is probably more true in woodworking than it is in mortal combat: "Some things cannot be taught. They must be lived." Thus it is with jointers.Thanks,
MelMeasure your output in smiles per board foot.
I can't describe the humps as slight. No board could be straightened. Valleys may not be as much of a problem. I would say that if you can get good joints with it, use it as it is.The best jointer I ever had was a Powercraft from Montgomery Ward. It appeared to be a relabeled Delta 6-inch, late 1960s vintage. That style is no longer available except at Harbor Freight & without blade height screws. FWW magazine lately compared 6- & 8-inch jointers (#160 & #180). If you must have a new one, read the articles. In a later issue, FWW praised a new Grizzly 8 which they could not get in time to review with the others. Mine now is a Yorkcraft. No complaints except that shipping costs were very high for me. You may live within driving distance.Cadiddlehopper
Powercraft from Mongomery Ward was made by ToolKraft in Springfield Massachusetts. You can find documentaion at OWWM. I used to visit the factory showroom when it was still in business.
There are a lot of tool brands that were never familiar to me. Did Toolkraft make all Powercraft tools? I saw an older Delta which looked almost exactly like mine. Anyway, it was a fine tool.Cadid
Sears jointer. My Sears outfeed table was straight for about six inches before it started down hill. Things to avoid. Yes avoid Sears. Maybe that is to all encompassing and blunt. Surely they make some good stuff.
To get a perfectly straight cut on a jointer the knives must be set so that the bottom of the scallops which are produced by the knives on the board are equal with the top of the outfeed table. Usually that requires setting the knives about .002" higher than the outfeed table.
Thanks for your post. Yours and others along this line make it come to light. It is so much easier when you have the adjustable outfeed table that trying to adjust the knives.
Over the years I have used a piece of notebook paper to get the height difference. It seems to be just perfect.
Thanks.
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