Jointer basic considerations

[Jules Dominguez]

In the very early days of my amateur woodworking I acquired a 6" Craftsman jointer. I tried unsuccessfully to use it and finally gave it away (about 20 years ago) as being of no practical value to the type of projects I did. I have done quite a bit of edge gluing since then and have always managed it okay using a tablesaw and hand planes to touch up the edges when necessary. I have a large stock of unplaned black cherry and a (pretty old) Ryobi 10" thickness planer.
I have some questions for those who are able to make good use of a jointer. How much thickness do you typically have to take off of a board which is moderately warped, cupped or twisted in order to end up with two flat parallel faces? What thickness wood do you normally start with? How long a board can you successfully control doing face-jointing on a joiner?

[Stephen Dixon]

I don't consider myself an expert by any means, but I'll try to answer. I usually have my jointer set for a light cut, about 1/64, and it always seems to take 3 or 4 trips across the knives to straighten anything out for me. Conventional wisdom says you can joint a board twice the length of your jointer tables, I haven't tried that, but I can joint 8' boards on my 65" jointer.

Steve

[Mike Holbrook]

I use to know a Jules, calls me all the time about camping & fishing, use to be a river rat, you know that guy? You did not say you are new to the Creek. Good to see you finally here making this post. Welcome to the Creek!

[Karl Laustrup]

Welcome to the "Creek" Jules. There are a lot of knowledgeable people here. While not all inclusive, let me impart my limited knowledge about jointers.

There is no rule for how much has to be taken off when prepping a rough sawn piece of lumber. The jointer is used to make one face flat and then using that face against the fence make one edge flat and 90* to the face.

Once that is accomplised it's time for the planer or TS.

Usually rough sawn is done in 4/4, 5/4, 6/4, 7/4, 8/4, etc. and you would be trying to finish it to 3/4" or whatever respective size you need.

[Charlie Plesums]

Key to how much you have to take off is how badly it is warped or cupped. If the warp is 1/4 inch, you need to take off 1/4 inch, or 1/8 inch from each end. If the warp is 1 inch, you need to take off too much.

I normally cut my boards to approximate length before planing. If I have a 1/2 inch warp across the whole length of an 8 foot board, rather than taking 1/4 inch off each end (in multiple shallow passes), I cut the board into the 2 foot (or whatever) pieces, and have much less warp to remove in each of the smaller boards.

Generally it is much easier to use the jointer on the concave side of the wood (so you are cutting the ends rather than the middle). Once it is perfectly flat, use the planer to make the other side parallel.

[Jules Dominguez]

Thanks, gentlemen. Thank you also, Mike Holbrook.

I understand the theory of using a jointer, i.e. you flatten one face of a board with the jointer and then cut a parallel flat face with a thicknesss jointer. I would consider a board that you can accomplish this with by removinga total of only 1/16 of an inch to be near perfect to begin with.
You can usually pull a very slight warp, twist, or bow out of the face of a board in the assembly process without building in any significant stress. It may not be possible to do that with a cupped board.
Another option to reduce face defects in a long or wide board is to cut it into smaller pieces at the start. before thickness planing it. And of course use a hand plane to reduce very small defects.
As for edge jointing, I normally have no problem matching the edges of boards after ripping them on the tablesaw, which is a 20 year old Delta contractors saw with the original fence. I use a home-made sled-type jig on the tablesaw to get one edge of a board straight when necessary, which is not uncommon given that I start with rough lumber. I adopted this approach based on the recommendations in one of the early Woodsmith issues.There is occasionally a small mismatch between board edges after ripping. These are usually easily corrected with a hand plane, and I definitely don't consider myself to be a highly skilled hand planer. I have pieces of furniture that I made 20 years ago with edge-glued boards that show no sign of separating today.
Do you jointer guys use your jointers mostly on the faces, or on the edges of boards? How much art is involved in jointing a board which is longer than the infeed table?
I'm not trying to be a smartass, but I'm still not convinced of the need to sacrifice the high $ cost and shop space for a jointer. Tell me more. Mike Holbrook will attest to my mule-headedness and the need for a really compelling argument to get me to spend money, even when I can afford it.

[Bill Arnold]

Jules,

I rely on the jointer (6", in my case) to flatten a face and square an edge, the typical way to use a jointer. Like Charlie, I cut my rough lumber to a bit oversize so I'm dealing with shorter (and usually narrower) lengths; i.e., ripping 8/4 to 2x2x30 (or whatever) for leg stock, let it acclimate for a week or two and then joint it and plane it. When I need wider stock for a panel, for instance, I cut it a bit longer than I need and use the thickness planer to flatten it; taking light cuts keeps the planer from pushing any bow out of it. Most of the time, I have my jointer set to 1/32" or less; light cuts are easier on the machinery and the material. I typically take even lighter cuts on the planer.

Regards,

[Mike Holbrook]

Attest, attest, attest, attest... for jeees 20+ years already. Ahhhh Holbrook you don't need a jointer :)