Jointer Use - Tips?

[vernal888]

Hello All: I've been able to become proficient with all my powered woodworking tools. Except the jointer, which I thought would be the easiest to use. Can't seem to get an uniform cut across the length of the board, and there is a noticeable taper from front (first end through) to back. I've paid close attention to setting infeed and outfeed table heights, and a steel straight edge across the length of both tables shows them to be flat. Still, when I feed the stock through, I get machining at the start, lessening to about the mid point, and then little to none until the last few inches. Multiple passes result in a tapered board. The machine is the Jet 6" stationary long bed.

Any and all tips appreciated.

[Duane Bozarth]

1. Hold the piece on the infeed table until roughly halfway along the length, then keep same pressure on outfeed table to end.
2. If same symptoms occur, indicates one (or worse case both) of the following...

a. Outfeed table is proud compared to knives, raising the work as you progress resulting in the observed lack of contact towards the end.

b. Outfeed table is not coplanar w/ infeed -- one or the other sags wrt to the other.

Start by making sure all knives are both at the same relative height and even across the head. If that is ok, lower the outfeed table a little and try again.

Check that besides the tables themselves being flat and straight that the are, in fact, coplanar.

Is this a new jointer so that you still have manufacturer's warranty to help?

[Greg G]

I, and many others, have posted fairly detailed summaries concerning the technique of setting up and using a jointer. I'm not trying to be a smart-a#$, but if you will DAGS (Do A Google Search) for the terms [jointer technique] in the rec.woodworking group, I'm certain you will find an entire day's worth of reading on the subject.

Then, if you have more detail questions, ask here again.

Sounds as though you are putting too much pressure on the feed side. You want to hold the stock down flat, but not press too hard. As the wood goes over transfer some of the pressure to the outfeed side. It's kinda hard to explain. Balance, technique, practice.

Our hands get tired of typing after a while... Good Luck!

Greg G.

[Dan Kratville]

I am a newbie to this news group stuff (woodworking too). Could you explain how I do a google search of a news group. I have many basic questions that I am shy to ask for the very reasons you just stated. Thanks! Dan

[Greg G]

Just go here, bookmark it for later.

type your search criteria into the box in the yellowish bar, and have at it.

Good Luck,

Greg G.

[wood_newbie]

Okay...here's a newbie's advice...

I don't know if what you describe is happening to you on all of the boards you're working with, but I'll pass along some advice given to me by the teacher who taught me.

Now before I start a flame-war, keep in mind, this guy was teaching a class of rooks, myself included. You pros out there may have better/different technique, and if so, please share it _politely_!!

If the board you are jointing is convex _towards_ the knives, it is very difficult to straighten it out on a jointer. This is due to the rocking effect that takes place. In a gross exaggeration, think of trying to "straighten out" a rocking chair's "foot"...where along the foot would you put the pressure in order to begin flattening it?

This would be true regardless of whether you were jointing the edge or the face of the board.

His advice was not to bother, but instead flip the board and joint the _concave_ side first. Then, if you're jointing the face, run the board through the planer with the jointed side down and it would flatten the the concave side. If you're jointing the edge, run the board through the table saw with the jointed side against the fence...the blade will do the rest.

Of course, the other issue with the tables/knives being co-planar and well-aligned is also true, but look into technique as well. This has worked well for me.

Now, again, for those of you with _fantastic_ technique, BE GENTLE IN YOUR REPLY!

[David]

I always sight down a board to be sure the concave side is down, as you've already mentioned. Figuring out which end to put first to reduce tear out is beyond me, so I make a pass and then check for tear out. If there is some, of course I reverse the board and that usually resolves it.

See! I was gentle.

Dave

[tom]

A newbie wrote: "His advice was not to bother, but instead flip the board and joint the _concave_ side first. Then, if you're jointing the face, run the board

through the planer with the jointed side down and it would flatten the the concave side. If you're jointing the edge, run the board through the table saw with the jointed side against the fence...the blade will do the rest. Of course, the other issue with the tables/knives being co-planar and well-aligned is also true, but look into technique as well. This has worked well for me. Now, again, for those of you with _fantastic_ technique, BE GENTLE IN YOUR REPLY!"

I think, except for getting concave/convex a little mixed up, you've decribed the technique very well. . Now grow a thicker skin so's we can abuse you! (Insert smiley face here) Tom

[wood_newbie]

You're right...my sentence should have read "...if you're jointing the face, run the board through the planer with the jointed side down and it would flatten the conVEX side."

In other words, joint the concave side, plane the convex side.

The thick skin thing made me laugh my ass off...so my butt is of course now concave...

[vernal888]

[bridgerfafc]

the jointer is for getting an edge straight, not for getting it parallel to anything else. once you have an edge straight, get the other one parallel on something like a tablesaw or thickness planer.

that said, it sounds like your jointer is still slightly out of tune. my guess is that the outfeed table is a hair high (or that the blades are a hair low), but it could be table droop.

here's a practise exercise for you. take a board that is at least twice the length of your jointer, straight or not, and mark a series of lenghtwise lines on it, about 1/8" or so apart. make the lines as straight and accurate as possible. now set the jointer for a shallow cut- 1/64" or less and start jointing the edge to the first line. flip the board end for end as necessary and start in the middle of the board if necessary, but joint to the line. then do it over again to the next line. do this a few times and you will gain considerable understanding of and skill with the machine.

[bridgerfafc]

sometimes the other edge of the board is worse, or you want to use it for something else, for some reason you really want to joint from the convex edge. sometimes both edges are convex. for this reason, it is a good idea to understand and be able to joint a convex edge.

[Mike O.]

Lets assume that the machine tables are good to each other and that the highest knife is not too much higher than the others. Assuming the machine is basically okay then the problem you describe has to be that the out-feed table is too high as has been suggested.

My suggestion would be to set the machine so that that it should be taking off a small amount. Run a piece a straight stock through to make sure your taking off just a small amount. Next, lower the out-feed table a small amount and run the piece of stock through again. Check the stock to see if you get snipe at the very end of the piece. If there is no snipe bring the out-feed table down a little more and run the piece again. Continue this (with small adjustments) until you see a little snipe at the end of the piece. Once you see some snipe at the end of the piece, you are a little too low on the out feed table. Now, go the other way and raise the out-feed table very slightly. Run the piece again and check for snipe. If you still have snipe raise the out-feed table a hair and run the piece again. You want no snipe but there is a fine line between snipe and no snipe. That's the line you're looking for.

Mike O.

[Mike Berger]

[JGS]