Replies

1. 
   scooter1 | Dec 01, 2004 04:12am | #1

   Whatever finish you used on the top, use on the bottom.

   Regards,
   Boris

   "Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934

1. 
   HowardAcheson | Dec 01, 2004 06:43pm | #8

   >> Whatever finish you used on the top, use on the bottom.And at the same time.Howie.........

2. 
   billballeza | Dec 01, 2004 06:06am | #2

   If I'm reading you correctly, you laminated something on the order of 37 or 38 maple strips roughly twice as thick as they are wide to get a tabletop 36 inches wide. Is this correct?

   If so, was there any particular reason for such an arduous glue up?

   I recently made a maple table too. It was six, 6" boards one inch thick. As soon as I got the table flat I stain/sealed both sides. The same day I got a first coat of poly on both sides.. coating the underside first and then flipping it over and coating the face side. My understanding is that it's important to finish both sides as quickly as possible in order to stabilize the panel and retard movement.

1. 
   rosewood41 | Dec 01, 2004 04:08pm | #5

   You read me correctly.  I glued up 3 sections of 13 strips and glued the 3 sections together.  I want it to look like a butcher block.

1. 
   billballeza | Dec 02, 2004 12:12am | #12

   The reason I ask is because ripping your boards into thin strips as you did must cause the parts to become very unstable from an EMC standpoint.

   Did you go immediately to glue up or did you wait awhile?

   In any event I'm sure the panel will flatten out again after the topside is finished and I'll bet the butcher block effect is terrific.

1. 
   rosewood41 | Dec 02, 2004 05:19am | #13

   I waited perhaps a week or 10 days to glue up the strips.  I used                          kreg jig face frame clamps for alignment and screws spaced about 6" apart.  I built up 3 sections, sanded them with my drum sander, and assembled them using my kreg jig and screwing them together.  Everything went well until I messed up the varnishing process.  I now have one coat on the top side.  I hope for the best.

1. 
   billballeza | Dec 02, 2004 05:58am | #14

   Sounds like an ingenious plan using pocket hole joinery. I've used  the Kreg system too.. mainly for leg to apron joinery and face frames. The guys on this tread are of the opinion that pocket hole joinery does not equate to "fine furniture" so I used mortise and tenon on the maple kitchen table I just made for my daughter.

   But I talked to the Kreg people on the phone once and they swear pocket hole joinery is stronger than mortise and tenon.. and even works well for attachment of the table top to the leg/apron assembly if you do it properly. (widen the holes to allow for movement)

   I am also partial to biscuit joinery for alignment in panel glue ups. I think all the new technology is good and very useful in many circumstances.

3. 
   forestgirl | Dec 01, 2004 09:36am | #3

   "Is it possible that the unfinished side dried out...."  Absolutely

   "would it be advisable to dampen the unfinished side with a sponge?"  You could try that.  The standard way to unwarp a board is to put it concave-side down on a high-humidity surface (the lawn works great).  I've done the same thing inside by using a barely damp towel with newsprint laying between it and the board, and a light shining from above to keep the upper (convex) side warm.

   "At present I have it clamped, overcompensating the warpage."  Gotta get rid  of the "warpage."  Take it out of the clamps before trying to even up the MC of the two sides.

   "I plan to spray varnish it this weekend."  Good idea to solve the flatness problem beforehand.  Then get finish on both sides ASAP.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
   Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

4. 
   UncleDunc | Dec 01, 2004 10:53am | #4

   Don't make any irreversible changes to it before you get it finished on both sides and give it a chance to reach equlibrium. If it was flat before you started finishing it, there's a good chance it will be flat again when it's finished the same on both sides. Finish it. Put it where air can easily get to both sides. If you have it lying flat, get some substantial stickers under it. If it's vertical, don't lean it closely against the wall, or whatever. Don't let the heat register blow on one side of it, etc. Then give it time. If it hasn't flattened back out after a week or two, then you can start thinking about modifications.

5. 
   VomSorb | Dec 01, 2004 05:00pm | #6

   You MUST put a coat of finish on both sides in the same day.  You can't do one side and come back the next day to do the other. 

   Go ahead and do the unfinished side and maybe the thing will settle back down for you.

6. 
   JohnWW | Dec 01, 2004 05:16pm | #7

   The unequal finish is the source of your trouble. 

   With the heat on, the relative moisture level of your shop's air is probably dropping to levels lower than when the top was glued up, causing the wood to further lose moisture.  The unfinished face of the table has lost moisture faster than the finished face, causing the unfinished side to contract more, and that contraction is the direct cause of the cupping. 

   You don't need to dampen the top or clamp it down, once the second side is finished, the moisture in the top will redistribute itself equally throughout the wood and, in a few days, the top will flatten out, it won't take a permanent set.

   John W.

1. 
   rosewood41 | Dec 11, 2004 04:40pm | #15

   Thanks for your expert advise on my warped table top.  After varnishing both sides it gradually flattened out and is now a proud addition to my newly remodeled kitchen.

   Thanks every one for your help.

7. 
   forestgirl | Dec 01, 2004 09:30pm | #9

   JohnW said:  "once the second side is finished, the moisture in the top will redistribute itself equally throughout the wood and, in a few days, the top will flatten out"

   Please let us know if it works this way.  It could save me some time in the future, if I space out and make the same mistake.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
   Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

1. 
   JohnWW | Dec 01, 2004 11:09pm | #10

   You doubt me?

   Seriously, wood expands and contracts all the time and it will do so forever, even wood that is hundreds of years old.  The wood will go back to flat when it gets back to the moisture levels the wood was at when originally flattened. 

   The problem right now is that the wood on the finished side of the table top is probably still at 10 percent MC and the unfinished side has probably dropped to 6 percent MC.

   John W.

1. 
   GHR | Dec 01, 2004 11:45pm | #11

   JohnW is correct.There is no need to worry about putting the same finish on both side. Just put enough finish on both sides to slow down the moisture loss.

8. 
   JohnWW | Dec 11, 2004 09:16pm | #16

   Peter,

   On my machine this type size is difficult to work with for any length of time, I get headaches from eye strain using the default 2 point type , so I go up just one type size to this, 3 point size, because it is a lot easier to use when working for hours on end at the computer, which my job sometimes requires. 

   This isn't the same as Bold, which is used to emphasize something and it isn't the same as ALL CAPITALS WHICH ARE UNDERSTOOD TO CONVEY SHOUTING and are very difficult to read in any case.

   I'm sorry if you misunderstood why I use a slightly larger type, it has nothing to do with ego or trying to get noticed, it is just a practical necessity.

   John W.

   ---

   Edited 12/11/2004 1:18 pm ET by JohnW

   
   

   ---

   Edited 12/13/2004 10:20 am ET by JohnW

1. 
   IanC | Dec 11, 2004 10:11pm | #17

   John, Please continue to post in the slightly larger yet unoffensive typeface.  I've come to equate it with good information I can rely on. 

   Ian

1. 
   JohnWW | Dec 13, 2004 06:21pm | #19

   Ian,

   Thanks

   John W.

2. 
   JeffHeath | Dec 12, 2004 04:41am | #18

   JohnW

   Please continue to print in any fashion you wish, as long as you continue to advise here.  I have come to trust and appreciate the advise you give in these threads, and don't care if I need a universal translator to get the information.  Besides, your slightly larger print IS easier to read.  Peter36 must be one of those guys always looking for a fight, so to speak.  Where I come from, we just take em' out in the alley and explain it to em'.  And on that note, Happy Holidays to all!!

   JC

1. 
   JohnWW | Dec 13, 2004 06:22pm | #20

   JC,

   Thank you also.

   John W.