[OP]
Guest
I have 36" boards 5 and 1/4 wide that are twisted to the point one corner is 1/16th above the jointer table when the other corner is pressed down. I tried ripping it in two and then face jointing but after four passes (about 1/32 per pass) I am not getting any where. The tables are in the same plane.
What is the proper technique to use?
Once the face passes over the knives is is theoretically flat. As soon as there is enough board past the cutter head to be safe, apply your pressure there to continue feeding. This allows the twisted portion to stay twisted as it passes over the knives thereby removing material from the offending area.
"A hen is only an egg's way of making another egg".
– Samuel Butler
[OP]
Guest
Thanks Glen; This is the first time I couldn't get something flat. I guess I was forcing the twist to follow the table thus keeping it twisted.Originally Posted by glenn bradley
Is that the way I should face joint all boards or just twisted ones?
I think you are pressing the board flat and the twist is springing back to some degree.
Like Glenn said, figure out which corner you want to be your "contact" or "control" point. Keep that point on the table by applying pressure there.
As the part moves over the cutter head and onto the outfeed table, you can provide gentle downpressure but not to the point of flattening the board or rocking it over onto the high corner.
Rob
Member
Power jointers are pain for removing twist on longish sticks. You have to keep the same 2 corners on the tables through the cut. You have to do this over multiple passes. One slip up and you're back to square one....which means kiss that 7/8 final thickness goodbye. Could easily mean 13/16 is gone too. Heck, you might be lucky to get 1/2 inch...
2 solutions for me:
1. Hand plane. Knock off the high corners with a hand plane and then go to the power jointer (or keep going with the hand planes).
2. Hot melt or CA glue some wedges to the low corners...giving you a more stable face to rest on the jointer tables. You have to be careful with this one. Dull knives can knock these wedges/shims off and send them flying.
Tim
on the neverending quest for wood.....
Member
Twist is when God wins.
Moderator
Twist is where the board goes back on the lumber rack or is cut down into small pieces for small components or kindling...
But, the hand-plane idea to knock off the corners is good. If the board does fit on the tables, then MINIMUM pressure for the passes and concentration to keep the board in the same orientation until it gets enough "flats" to do it by itself is necessary. It's somewhat an "art"!
--
The most expensive tool is the one you buy "cheaply" and often...
Member
Can you steam the twist out? Or will it come back later?
The opinion of 10,000 men is of no value if none of them know anything about the subject.
- Marcus Aurelius ---------------------------------------- ------------- [SIGPIC][/SIGPIC]
No Problem. That is the way I 'mostly' joint boards but jointer technique can almost become a religion to some folks. The raw basic is to move the material across the cutters safely but not with such a death-grip (I've done this my fair share of times) that you defeat the tool's purpose.
Twist is a bear on longer boards but can be dealt with. I try to cut close to length and width (no too close) on twisted boards so I don't fight anymore twist than I have to. Unnecessary length will require you to remove more material than otherwise might be required. Also, don't be afraid to use a handplane or rough grit sanding block to "pre-knock" (is that a word?) the high spots off.
"A hen is only an egg's way of making another egg".
– Samuel Butler
[OP]
Guest
Thankyou to everyone. I figured it out mostly. Tim Sproul kinda gave me an idea. On one of the worst boards I did the end in about 8" and then did the same to the other end and then ran the whole thing through. It helped quite a bit.
Member
Gary Rogowski demos a good jointer technique for removing cups and twists in a video clip on the FWW site.
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