Replies

1. 
   BG | Feb 10, 2003 12:30am | #1

   BJ,

   I used 16/4 oak from old pallets on my workbench.  Finding them was pure luck.  I just finished a new table the same size as the workbench only this is for the lathe and has a 5/4 poplar top and the legs are 16/4 doug fir. 

   Personally, I'd use either wood and glue up if necessary.  This is a work bench and your gonna beat the hell in it. 

2. 
   HowardAcheson | Feb 10, 2003 04:53am | #2

   The primary problem in gluing up 8/4 oak is getting enough pressure on it go get an optimum bond. For hardwoods and yellow glue, about 200 lbs/square inch is required. A 3.5" x 30 inch long surface will require 21,000 lbs of force (10.5 tons). A 6" "C" clamp exerts about 1,000 to 2,000 lbs/square inch so you will need 10 or more clamps to get the optimum bond.

1. 
   SVSander | Feb 11, 2003 01:58am | #3

   Howie,

   Can you tell us where the figures for clamping pressure came from? This is exactly the opposite of what I was taught -- just enough pressure to bring the smooth (jointed) surfaces in contact. I was taught that excess pressure could actually starve the joint of glue and result in failure.

   Thanks,

   Dick Baker

   Sunnyvale, CA

1. 
   HowardAcheson | Feb 11, 2003 03:02am | #4

   Understanding Wood by Hoadley, Taunton Press

   US Forest Service, Forest Products Laboratory, Chapter 9

   http://www.fpl.fs.fed.us/documnts/FPLGTR/fplgtr113/fplgtr113.htm

   In most shops it's virtually impossible to put too much pressure on a glue joint. "Starving the Joint" is a myth.

1. 
   SVSander | Feb 12, 2003 05:03am | #7

   Thanks for the guidance. I checked the refences and have "recalibrated" my thinking. (I also found an additional reference: "Gluing & Clamping by patrick Spielman.) I will use more clamping pressure in the future. The Wood Handbook by Forest Products Laboratory does indicate that excessive pressure can cause a starved glue joint, but the pressures involved are unlikely to be achieved with hand-operated clamps -- except, possibly, with very small work pieces. I love to learn...

   Dick Baker

   Sunnyvale, CA

1. 
   RANGERP75R | Feb 12, 2003 08:42am | #8

   Dick

      A little late here, as what needed to be said has been already. I thought I would throw in you might pick up a copy of Hoadley's book, "Understanding Wood". You will open up a whole new avenue of approach an a wealth of information with this book. Nothing short of fantastic.

   Have a great day...

   sarge..jt

3. 
   JsHerbel | Feb 11, 2003 03:53am | #5

   It does not matter if the material for the legs is "quartsawn" because if the legs are square, meaning equal width on all sides, there will be equal amounts of radial and tangential surfaces.

4. 
   dpearce | Feb 11, 2003 04:38am | #6

   BJ: I assure you, that if you use the 8/4 material, and you joint the glue-up surfaces with a jointer, and then use Gorilla Glue, they will NEVER COME APART !  I have laminated legs out of every kind of wood imaginable, and then turned, planed, and tortured in every way I can think of, and have not had a glue-joint failure.  Iwould recommend that the wood be appropriately dry prior to using it and that you wet both surfaces prior to applying the gorilla glue. I would place a clamp about every 6 inches or so.  If you have larger clamps, you can place two sets of leg parts back to back in each group of clamps.  Good luck. [email protected]

5. 
   BenM | Feb 12, 2003 09:14pm | #9

   8/4 should be fine and may be a little more stable because it takes a long time for 16/4 to dry.  Coose the woood very carefully for a good grain and color match.  If you do you will never see the joint line.  Also, try to glue it up so the heartwood side is on the outside (assuming the pieces are flatsawn).  Then if there is any movement in the wood due to additional drying you won't get an open joint.