Replies

1. 
   JimW | Nov 01, 2004 08:56pm | #1

   Whether or not your planing by hand or machine, it is better to flatten the panel after it's glued up.  No matter how hard you try, the joints will probably never be perfectly flush.  This isn't to say that your boards don't need to be flattened at all.  If there is an obvious bow or twist, take care of it before glue up.

   Each board should be squared and flattened (see FWW #160) for a good article about jointing and planing.  Even though it's geared toward machines, the same ideas apply to hand planing.

   Jim

   Coventry Woodworking

2. 
   JohnWW | Nov 01, 2004 10:30pm | #2

   Each board should have one truly flat face and one or both edges accurately squared to the good face, depending on which edges are being glued.  If you are moderately careful during your glue up, it will only take light scraping for a few minutes to get the table's surface ready to finish.  If each board's face and edge is correctly squared, the glued up top will come out flat automatically, you won't have to flatten it. 

   Gluing up "rough" and then trying to flatten the whole panel afterwards is doing it the hard way.

   John W.

   
   

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   Edited 11/1/2004 3:51 pm ET by JohnW

3. 
   Alan | Nov 02, 2004 12:19am | #3

   Dimitri,

   I have to disagree with John W, and agree with Jim W. 

   Because each board will have its own little faults, trying to plane everything straight and square prior to glue up will almost always accomplish little more than doubling the amount of work you have to do.  The easiest, and less time consuming way is to wait until the panel is glued up, and then work on all three boards at the same time.  That way you'll know you're dimensioning all three the same.

   I love using planes to dimension stock.  A sharp scrub plane makes the going easy and amazingly fast.  Have fun.

   Alan

1. 
   dimitri | Nov 02, 2004 03:25pm | #6

   Alan,

   Thanks for your wonderful advice. My thinking process was also in the same direction as yours but I wasnt 100% sure. It makes sense to true the face of the panel after glue-up. What about if one of the boards is fairly cupped before glue-up? Is it still advisable to glue all three and then plane or to do some quick flattenning on the one cupped board and then do the glue-up and flatten after that?

   I have been tinkering on making a scrub plane from some planes I have as spares. I read in Garrett Hacks book on planes that you can even use a beat up #4 and modify it to be a scrub plane. He also mentions using old wood coffin smoothers or even transitional planes. I have the following planes in my shop that can be modified to work as a scrub plane:

   1. A #4 stanley. (I already have one as a smoother)

   2. 2 wooden very old coffin smoothers with a wide enough throat to be used as a scrub.

   3. Two transitional planes.

   Garrett Hacks talks about curving the blade on the grinding stone slowly to form a scrub plane blade. Also he mentions about opening the frog up so large shavings come through(this would apply to the #4 only). In addition he says you have to raise the chip breaker up.

   I just purchased last week the new #4 low angle smoothing plane from lee valley. Its really nice. I also got the high angle blade as an option for it.

   What is your opinion? Which plane would be best to modify?

   thanks,

   Dimitri

1. 
   Alan | Nov 03, 2004 02:25am | #7

   Dimitri,

   As to which plane to turn into a scrub, I would think the narrowest one would work best.  A scrub hogs off lots of wood in a hurry.  A wide scrub would be more work to push through the wood than a narrow one.  All the scrubs I've seen are pretty narrow, about the same as a #3.

   You should flatten one side of a cupped board prior to glue up, for the simple reason that otherwise it will be next to impossible to get a flat panel.  Flatten one side, then plane both edges square to the flattened side.

   When you glue up the panel put the flattened face down.  That should bring underside of all the boards into pretty good alignment, which will reduce the amount of work you have to do flattening both sides of the panel.

   Trying to get all the boards exactly the same thickness prior to glue up is a lot of work, which will usually accomplish very little.  The panel will almost always be a little uneven no matter how careful you are when you glue it up.  You'll wind up having to plane both sides anyway, so IMHO there's no reason to do it twice.

   Alan

4. 
   Froed | Nov 02, 2004 02:37pm | #4

   I agree that you should establish one flat face for the individual pieces, along with squaring the edges to those faces.  This should give you one flat face after you glue up, if done with care, and results in more useable thickness.  Why?  Because you'll take less stock off each individual piece than you would if you glued up three boards (meaning less work), then trued the whole face.  You'll still have to flatten the second face of the assembly, after touching up the first face, if necessary.

   Also try to orient the pieces so grain direction is consistent between adjacent boards.  Then you won't have to switch directions to avoid tearout from one piece to the next.

   Froed

5. 
   BG | Nov 02, 2004 03:11pm | #5

   Dimitri,

   You've got some knowledgable people responding and some interesting perspectives.  From a novice point of view, it would seem flattening first would be the best idea.  Tight seams would be the first objective and detecting that with unflattened boards would seem to me to be more difficult.  Also, I'm a left hand planer..I can't plane form the right side so reaching over a long distance would be problematic to do a major flattening.  Yes, I could flip the board but the grain would have to be consistent with that effort...or access to the other side of the workbench.  So if I flatten first and just have some smoothing and scraping to finnish up that would seem to be best and minimize risk. 
6. 
   Crunk | Nov 03, 2004 02:38pm | #8

   ALWAYS, ALWAYS, ALWAYS after glue-up.  Straighten edges, do your glue-up and then flatten the panel as if it were one of the really wide boards available 200+ years ago.

   That's the whole point.

   Anybody who suggests otherwise hasn't quite figured out the craft I'm afraid.

   
   

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   Edited 11/3/2004 7:44 am ET by BossCrunk