Jointing/Planing

Paul_H · February 02, 2003, 04:39:33 PM

The topic of jointing came up here the other day in regards to planing cupped boards.Can some one explain it again in laymen terms,or point me to some links?.I have never been able to learn much from reading,unless I can see what is being described(picture,diagram,or watching someone do it)

When we were planing the floors,cupping wasn't a problem,but there was some slight crook in some of the boards.Most of the boards were 8'-12',should they have been cut shorter prior to being fed into the planer,or chopped afterward?

By crook I mean with the board laying flat,wide side facing up if you looked down the length of the edge,it would tend to go to the right or the left.

Is that the proper term?

Tillaway · February 02, 2003, 04:53:25 PM

That term works for me, I knew what you were talking about.

I don't know about when you should cut but I don't see as how it would make a difference. Leaving them long would mean fewer pieces to feed the planer then cutting them shorter to joint out the crook/sweep would seem to make sense to me.

But heck, this is out of my area. So I yield to those with actual experience.

Tom · February 02, 2003, 04:55:52 PM

Board drying defects

Click on the the above link to go to a thread that has pictures and descriptions of some board drying defects/movement.

Usually crook is a common wood movement for quarter sawed boards. Straightening a board with a crook requires sawing one edge straight by using a straight edge and a skill saw, a jig on a tablesaw or multible passes on a joiner, cutting away the convex side. Once one edge is straight, the other is made straight by use of the fence on a tablesaw.

Crook can be pulled tight to the first board and nailed by use of a board straightener. It is a jig that fits over a joist or a nail driven in the subfloor. Of course, straight boards are best.

Paul_H · February 02, 2003, 07:20:47 PM

Tillaway,
I'm just happy to be understood,it's hard to talk without waving my hands around ;)Thanks

Thanks for the link Tom,I remember another thread where you had mentioned that flooring should be put down bark side up that has been cut from near the center of the log.

Is that to avoid pith getting on the floor? :P

Bro. Noble · February 02, 2003, 07:32:39 PM

Paul,

We uthe tile on the bathroom floor tho we can juth mop it up.

Noble

Paul_H · February 02, 2003, 07:41:28 PM

Noble,
I couldn't help mythelf :-/

Tom found me the link to the thread on flooring.

Pith Problems

Fla._Deadheader · February 03, 2003, 04:16:18 AM

Use sawpalmetto berry pills to cure yer problem, Paul ;D

Rick Schmalzried · February 03, 2003, 11:41:55 AM

Tillaway,
The biggest problem with planing rough boards is that the reference surface is on the opposite side of the board as the cutter. The only thing that a cutter can do is cut the board to be the same thickness throughout the board.

A jointer has the cutter on the same side as the reference surface. It cuts away a surface, and then immediatly supports that surface with the outfeed table, which is a flat plane. By keeping the outfeed securely on this flat plane, you end up with a flat surface on the board. When this is then ran through the surfacer you end up with a flat board on both sides.

I haven't seen problems with the rollers flattening out cupping, but I certainly have had problems trying to remove twist and bow from rough lumber without first running it through the jointer.

People also run into problems when trying to use a jointer to also thickness lumber. There is no way to keep the thickness the same across the board because the top surface is free to float in mid air. If the board is tapered at first, it will end up tapered when you are done.

Let me know if this is unclear.

woodmills1 · February 03, 2003, 12:21:52 PM

If boards are badly curved with what we are calling crook i will put them on the woodmizer for one pass before I joint them. a sharp blade will make a nice straight edge. this is also a way to get boards of slightly different width to be more uniform, using a pass on both edges on the woodmizer.

I bought my dry kilns from a person in peperel(sp) mass, he buys a lot of rough cedar and sells it finished. He has a lot of machinery, including a 5 head moulder. but one piece really interested me, it was a 20 inch jointer that was rigged with a sort of down pressure device. not quite a roller, it had a large drum with many L shaped feet sticking out of it. each L had an individual spring on it, so while it did put down force toward the cutter it road over the irregularities in the piece and cut like a true jointer. he passed the rough lumber through this then flipped it over and finished it on the thickness planer.

he also had a pairof large wheels with bar clamps coming out of them like spokes so he could glue up a wide panel then rotate the wheels to get another set of clamps for another panel.

Rick Schmalzried · February 04, 2003, 08:32:03 PM

I have seen (well actually not in person

) both types of devices you are describing and really drooled over the jointer power feed. I have been trying to figure out how I could do something with some spring loaded pneumatic wheels like on a hand cart. Of course that would mean that I would need a 16" jointer to mount it on and that won't quite fit in my existing 2 car garage.
If only I had a new shop.

I know...I need to bring out the free shop chain letter. You know, send a board to the 5 people on the top of the list and put your name at the bottom, and then send to 10 people. By the time your name gets to the top you will only have had to send 5 boards, but you would have enough boards to build your own shop for free !! 8) 8) 8)

Hey Jeff, would this fit better in the For Sale area or the Wanted area. I would be willing to put your name at the top. ;) Of course I guess that would mean you would only get 10 boards :D :D

Brian_Bailey · February 05, 2003, 05:21:10 AM

I would be hesitant in putting a power feed on a jointer because you would basically encounter the same problems in flattening a board that a planer would have.

If the board has any bow to it, it will spring back after being run thru the jointer using a power feed.

Rick Schmalzried · February 05, 2003, 08:29:22 AM

Brian,
I guess that I have to say "it depends".

Proper operation of a jointer has a majority of the pressure on the outfeed side so that it is pressing the just cut surface onto the flat outfeed table. I have thought about having the power feed only on the outfeed side such that I would manually have to start feeding the board through, which would keep from flattening the board. The other thing to keep in mind is that you don't need 1000 lbs of down force to feed the board. I doubt that I put even 50 lbs of down force manually when jointing. As long as I keep the total pressure in that range I don't think I would have problems flattening the board. Now if I were to install pressure rollers such as are on a planer, I agree that uncupping with the resultant spring back would be a problem.

I guess it really doesn't matter as right now it is all a pipe dream that I will probably never get to. :

--Rick

Don P · February 05, 2003, 08:37:10 AM

The machine you guys are describing is called a facer. The "fingers" provide soft feed that guides the board across the cutterhead much like your hand would. Facing and then planing is the best way to surface. The facer was relegated to the back lot at one shop I worked at when we got a throughfeed moulder to replace the pushfeed like Paul's. The front feedwheel was "soft" and preceeded a bottom facing head to which was attached a fence side rabbeting cutter that gave a jointing reference line for the 1st side head to use...essentially it faced and jointed and then the other side matched and finally the top planed. On that machine there was finally a 5th universal head that could be put to work on any side. Feed wheels were distributed all the way through the machine. It was limited to 7.5 inches wide and we only used the planer for wide boards. If an order came through for wide panel stock or whatever, we then selected the best, flatest for that. Old woodworkers used "winding sticks" to see and hand plane out the twist in their lumber, a long jointing plane was used for the edges.
We broke down most wide boards for panel stock and presurfaced it through the moulder before sending it to the glue jointer and then the high frequency glue machine. Another plant used a straight line rip in place of the jointer. The glue reel Woodmills described was a nice shop scale piece often clamped with air impacts to assure even clamping force. As the "ferris wheel" came back around the stock would be ready to unclamp and the next layup ready to go in.
The RF gluers I worked on had a top and bottom platen about 4x8 and side clamping blocks all air operated. A group of panels was laid up and slid into the machine. The top platen comes down, the sides come in. Then in our case 15-20KW of radio waves is shorted through the glueline from top to bottom platens.About like shorting a college radio station out through the wood. It excites the water molecules in the glue and cures the glueline to a "handling bond" in 30-60 seconds. In one shop we used catalyzed PVA glues, in another urea formaldehyde. When in full tilt production the rf machine could keep up with 2 straight line's, a double end tennoner was used to size the panels and then a triple belt wide belt sander finished them.
One interesting aside, you hear about more oaks getting hit by lightning than about any other tree...oak would "peg" the machine often, drawing too much current and tripping. I would have to turn the output down on the rf generator. The wood itself was a pretty good conductor.

Brian_Bailey · February 05, 2003, 11:39:02 AM

Rick - I agree that power feeding a board with just cup wouldn't be much of a problem. But, how many roughcut boards have just cup as a defect. If you are using figured lumber or a board from a tree that has spiral grain, you'll be encountering many other kinds of warp. Many of those kinds of warp will be in the same board. Each has its own way of being delt with. Too just run a board over a jointer using power feed will not correct the board for a flat face in a lot of instances.

Here are some examples of warp.

Don P - I'd love to have a machine like the one you describe, but, I think it would take up my whole shop and make me poorer than what I am now. Sounds like a production unit.

Your statement, " Old woodworkers used ...." made me feel older than what I am :D. I currently use winding sticks, a scrub plane, and various other fossil woodworking tools to make a lot of the furniture that I produce. A hand planed surface will beat a machined one any day IMHO.

Bro. Noble · February 05, 2003, 12:57:11 PM

DonP,

Your comment on lightening striking Oak is interesting. Seems to me like lightening always hits a walnut if there are both oak and walnut nearby. I've heard that walnut is higher in minerals and therby attracts lightening. It sure leaves a lot more ash than oak when you burn it, seems like.

I'm not saying you're full of prunes :D :D, just telling what I've heard and observed.

Noble

Don P · February 05, 2003, 01:56:29 PM

I can't remember what the gluer did on whirlnut, we never did to much with it. Now prunes would have likely blown the...end clean off the machine.
The platens on those gluers was a sheet of plate aluminum about 1/4 inch thick and periodically we took them out back and scraped them down. I forgot and got doing something else one afternoon and left one outside overnight. The shop was not on the best side of town. The next morning I get there and this "lady" is jumping up and down on the thing trying to fold it up and put in her grocery cart :D.

Brian, The facer was about the size of a full size pickup with topper, the gluer took up about 3 parking places, the drums on the wide belt ,like the drums on your belt sander, were 5' long, 12" dia and weighed a ton each

. It was some neat equipment...I got Craftsman and Jet :D.

This is a sketch of a ripsaw we used upstream of the moulder. It's built on 2 rollertables with an old powered ripsaw in the middle. The fence pivots on the red arms and is a 20 foot stick of 3/8x4 flat stock. If you put the boards on it concave edge to the fence on the first edging pass it did a pretty fair job of straightening.

Brian_Bailey · February 06, 2003, 05:59:31 PM

Here's my low tech way of dealing with warp in a board. The board has some twist (rack). It is to wide for my 8" jointer, so I use a scrub plane to level off the high spots. I use my bench table as a reference for flat. When the board doesn't rock on the bench I know it's ready to be thickness planed. If I feel really ambitious, I'll use the the fore plane to flatten the board, but, most of the time the board goes to the power planer.

This is the business side of a scrub plane. It can remove a lot of wood in a hurry. You can see the cuts in the board above the plane.

Obviously, this isn't a production setup, but it sure is soul satisfying to listen to the hand plane doing it thing.