Hi,
I’m pretty new to woodworking and brand new to this forum. I have a Ridgid 6-inch jointer in my garage newly on loan. Just starting to use it to face-joint some mahogany for a couple nightstands. I’m immediately having problems.
My boards are coming out tapered. Some of my stock is a bit twisted to begin with, so I’m having to make several passes, and with each successive pass, the boards are acquiring more of a taper (and I’m not doing a lot to eliminate the twist).
I don’t know if it’s a set-up problem or my technique. I read several articles on jointer tune-up and it *looks* like everything is ok: tables seem parallel to each other, knives seem parallel to tables. Don’t know if in my inexperience I’m missing something.
Just to see if I wasn’t being patient enough with my stock, I ran a piece of dead-flat MDF through a few times and sure enough, after a few passes it was tapered (and maybe even a bit twisted).
Any thoughts? Thanks much,
Jeff
Replies
"I ran a piece of dead-flat MDF through a few times and sure enough, " Oh dear, oh dear. Pleeeeeze don't run MDF through your jointer. Unless you love sharpening and/or buying new blades.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Is the taper along the width of the board, so if you are looking down the edge from the end, one side is narrower than the other? If this is the case it's either your infeed/outfeed tables are not parallel (most likely cause) or one or more blades are not parallel to the outfeed table. I had the same issue on my Griz, and just live with it since shimming it is a pain. I solve the tapering issue by running it through the planer.
Slacker Extraordinaire
Specializing in nothing but knowledge in everything.
You may want to check your outfeed table. It should be somewhere between 1/32 and 1/8 depending on your jointer's specifications HIGHER than your infeed table. This is to replace the material that is removed.
(Oh yeah definitely agree with forestgirl. Running MDF or any other engineered wood products through your jointer or planer for that matter is a bad idea.)
Hope this helps.
This may or may not help with your problem, but as you're new to woodworking, you may find it helpful. Mark Duginske's book, Mastering Woodworking Machines covers set up and adjustment of many of the machines you're likely to have in your shop and has quite a bit on the jointer. It was first published about 15 years ago, but most of the information is still relevant. You may find more detail in single-machine type books, but this one is nice if you want a little bit of everything.
http://www.taunton.com/finewoodworking/store/pages/070136.asp
The problem may be twofold, technique and table height or parallelism. Set the infeed table for a 1/32" or lighter cut. Keep pressure on the INfeed table until most of the board has passed the cutterhead. Then switch pressure to the outfeed table to finish.
Assuming your technique is good, then the tables may not be in plane ( called coplanar).Adjust the infeed table to the exact height of the outfeed table. With a good straightedge,steel preferably, there should be no gaps under either table.
If there is a gap,the tables may not be machined perfectly or the outfeed table must be adjusted to parallel with infeed table. Refer to manual for adjustments if it needs it. Also, the knives must be parallel along the cutterhead and all knives set to the same height.Check the archives,there is an excellent post that describes the fix better than I.John White may be the author if I recall.
mike
Mike4244 has good advice, but he omits that the blade to outfeed table relationship must be such that the blades are slightly proud of the table by a few thousandths of an inch. If absolutely coplanar or below, your cut will taper. To check this, place a steel scale on the outfeed table extending over the blades. Rotate the head as if cutting. The scale should move toward the infeed table as the blade drags across it. It should move no more than 1/8". You may correct the problem by adjusting the blades individually or by adjusting the outfeed table height. The latter works if you are lucky.
Cadiddlehopper
You're correct ,I had it in my mind when typing the post to set the outfeed table a hair lower. Maybe the thickness of a piece of paper.Thanks for adding this omission.
mike
It's possible that you have an adjustment problem, but the "problem" that you're describing sounds normal for a jointer.
Face jointing makes one face flat, but there's nothing to guarantee that it will stay parallel to the opposite face of the board. If you're getting a flat face, your machine is doing the right thing. If you want both sides parallel, you may need to plane the board afterward.
Even with flat and parallel faces to start with, it's really easy to put a taper into a board with successive passes. Taking light cuts and practice will reduce this tendency.
Pete
Edited 6/5/2006 9:43 pm ET by PeteBradley
"Taking light cuts and practice will reduce this tendency."Someone told me that taking light or shallow cuts was hell on your blades, and dulls them quickly. Were they full of it?
That's a new one on me. Hard to belive it's good parctice to only take heavy cuts on a jointer.
Pete
Pete,
Very light cuts, where only a hundredth of an inch is taken off or as often happens in this case, there is no cutting real action and the blades are merely rubbing against the boards surface will accelerate wear.
A moderate cut of a 32nd of an inch through whatever the machine can handle without bogging down is the best. Taking a too shallow cut is especially damaging when taking the first passes on rough sawn wood because the rubbing action against the dirty surface of the stock will do quite a bit of blade damage.
John White, Shop Manager, Fine Woodworking Magazine
I'll buy that. When I wrote "light", I had in mind a cut that still takes off a noticeable amount of material. I avoid putting any knife tool to a raw or dirty surface whenever possible.
Pete
This was good info for me, from both you and John White, who is a very good person to work with at FWW, BTW. Someone told me never to run wood through my jointer at 1/32" cut. I was told a 1/32" cut would dull my blades immediately. Maybe I should not hold all the info on this board as gospel.Nevertheless, I still cut wedges on my jointer when face planing. I just need to buy a planer and be done with the problem.
> Maybe I should not hold all the info on this board as gospel.Ain't that the truth!! There's a lot of great information on FWW, but there's always a certain percentage that's off the mark. I try very hard to post advice only from firsthand experience. I find myself hitting the Cancel button a lot more than I used to.Pete
Jeff,
There are several possible reasons for your problems: improper technique, incorrect settings of the outfeed table and blades, dull blades, and possibly, but not likely, misalignment of the tables.
Rather than take an inefficient random approach to solving the problem, you should read an article on using a jointer and an article or book chapter on setting up and checking your machine. Without this basic knowledge you will be frustrated needlessly when trying to use the machine.
In the mean time, running a piece of MDF has probably dulled the blades very badly, even just one pass, and you will need to change out the blades before trying anything else since a jointer with dull blades simply can't be made to cut properly.
John White, Shop Manager, Fine Woodworking Magazine
Here is a good web page that will take you through your jointer setup. http://woodworking.homeip.net/wood/Tuning%20Tools/Jointers/Jointers.html
I had the same problem, and this cured it. Just go through all of the steps and it will be set up correctly. Make sure you have an accurate straight edge.
Dan
Great site - good advice. I printed all three guides and put them in a binder to keep in my shop.
Thanks!Regard it as just as desirable to build a chicken house as to build a cathedral. Frank Lloyd Wright
I do not have a jointer just yet, however I have used one in the distant pass. I seem to remember and this may be bad advice so someone chime in, that it is a good idea to feed the stock into planer one way and then on the second pass to feed the stock from the opposite end. This seems like it would reduce the taper effect. Again, it has been years since I used a jointer and I am just now setting up a shop and have not gotten to the jointer purchase yet, so if this is bad advice please say so.
Wayne
Running the stock through in both directions can reverse any taper caused by bad adjustment but it also increases the chance of tearout. The grain direction should be such that the knives won't grab and pull the fibers down, with tearout as the result. Same principle as hand planing.
"I cut this piece four times and it's still too short."
Makes sense....thanks for the clarrification
Some tips, no.11.
I agree with Cadiddlehopper. My jointer worked fine for quite a while, then I started getting a taper problem like you refer to. I patiently set the outfeed table of my jointer to the height of the blades and taper problem didn't go away. Experimenting to make it work better and easier, I dropped the outfeed table a couple thousandths and that seems to have solved the problem with no change in technique. I occasionally get a couple thousandths of snipe at the very trailing end of the board.
Steve
Just wanted to check in and say thanks for all the great responses. I checked and rechecked the tables for parallel, checked the knives, still seemed okay, so I'm going to try the suggestion of lowering the outfeed table just a hair. I'll post again when I get it figured out.
Jeffro
I would set and adjust my jointer as has been described.If after getting everything properly fettled, you still have a problem, consider your technique:1. Do you chalk the face of your board before jointing? (Helps to see where material is being removed).2. If you have a twisted board, and you see a taper beginning after a few passes, alternate ends with each pass (take off no more than 1/32" on each pass). If you get tear out, you can clean it up later on your second milling- either on the jointer or with the planer.3. If you have a really twisted, wound board, knock it into approximate square with a scrub plane, then joint it.Glaucon
If you don't think too good, then don't think too much...
I have a 6" Delta with the same problem. I have triple checked every setting, checked the knives, table heights, everything. Never have been able to figure it out. I must have bad technique, doing something wrong. My solution was to quit doing face jointing with it, because I was ruining every piece of wood I put through it.
I once owned a device for measuring blade/outfeed table height. Instructions recommended that blade be proud of table by .003-.004 inch. Consider that each cut is actually concave. It explains the need for clearance.I once owned (but returned) a Sears jointer because the outfeed table had a huge hump in it. No board could be straightened with it. If all adjustments have been attempted & it still doesn't work, lack of planarity or coplanarity of the tables is suspect. A machinist's long straight edge & feeler gauges are all you need to check it.Cadiddlehopper
Your problem is typical of most jointers. First of all, do not run any type of manufactured board on your jointer as it will destroy your cutting edge. Even plywood edging will dull the knives at the glue lines. I have used many jointers over the years and have found that tapers occur when planing both sides of a board almost always. I agree with another post that stated it can be kept at a minimum by reversing the direction of feed after each pass. This problem seems to become worse as knives become dull and also in wider stock. It also seems to be worse in harder woods. Always plane one face on the jointer and the second on a planer. If you have no planer, and you have the time and muscle, you may plane the second side by hand.
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