Replies

1. 
   eddiefromAustralia | Sep 10, 2003 01:06pm | #1

   Maurice,

   In my opinion (added these words as an afterthought), the way in which you've drawn it is the best way to orient grain - to make short grain sides is asking for trouble in this design.

   You will run into trouble with expansion.  I allow 1mm per 100mm width (oddly enough, 1%) movement summer/winter.  I'm guessing that the pottery barn shelves have a base of 8mm ply, which avoids this problem.

   If you have to use solid wood, use a barefaced tongue and groove (or full housing) to anchor the base to the side, pegged at the front (or nailed/screwed somehow) and allowed to float in the trench.  The backboard will cover up the movement due to shrinkage, so you should be fine.

   All this hinges on the fact that your wood is close to equilibrium moisture to begin with.

   Cheers,

   eddie

2. 
   BG | Sep 10, 2003 01:52pm | #2

   Maurice,

   I would agree with everything Eddie said.  I gotta believe the Pottery Barn shelves are plywood with wood faces.  I would only add that if you do a T&G connection between the shelf and the sides make the ends closed...like a vertical breadboard...that would provide additional strength to help keep the shelf flat.  You could then peg and glue in the center and peg and let float on the ends.  But I'm not sure its worth all that...and I would consider ply for the shelf.. 

1. 
   Robin | Sep 10, 2003 06:22pm | #3

   Pottery Barn's are MDF - looked at the addtional detail.  Glad I looked at this one.  Think I might give this a try with some adjustments for my plants that I bring in for the winter.  The way it sits on it's 45deg angle with no back legs would make it perfect for placing in front of a window.It's football time in Tennessee!  Go Vols!!!!

1. 
   mauric6943 | Sep 11, 2003 07:28am | #11

   Rob - If you went to the detail link at Pottery Barn it does say the shelf sits at 45 deg but I'm pretty sure that is wrong. If it were 45 deg the shelf and wall would be an isosceles triangle.

   I'm estimating about 11deg for my design. This link shows a shelf built by another WWer and I think his are about 15deg.

   http://odin.ac.hmc.edu/~dougw/

   The sliding dovetail sounds good but not sure I'm up for that quite yet.

   Thanks again

   maurice

1. 
   Robin | Sep 11, 2003 05:12pm | #12

   Thanks so much - hopefully I would have figured that out before I made the first cut!  15deg does sound better and is probably closer to the angle of the one from the PB.It's football time in Tennessee!  Go Vols!!!!

2. 
   mauric6943 | Sep 10, 2003 06:29pm | #4

   Thanks for the suggestions.

   PB shelves are painted MDF. $230 for painted. They have a newer version that is plywood veneered for $300. I said I could build for less that that.

   Not sure I understand the 'ends closed' part.

   T&G - glue and peg in the middle. As shelf bottom expands will move out the front and back of shelf - correct. I should not glue the shelf back to the bottom at all just the sides. Along this same line could you glue/peg the front and have all expansion happening out the rear of the shelf?

   Thanks again

   maurice

1. 
   BG | Sep 10, 2003 08:39pm | #5

   maurice,

   Eddie mentioned 'fully housed' on the T&G and I express this as closed end.  In other words, rather than run a dado the complete length of the side, stop short of both ends so you can't see the tongue of the shelf coming through.  As far as gluing in the front verses the center..sure.. and let the rest float ..but attach additional pegs.  This all assumes you use solid wood...not necessary with ply or MDF/MDO. 

   One other point, I may be misinterrupting.  The back rise can be glued to the shelf bottom the whole length...long grain to long grain...

   Edited 9/10/2003 1:42:15 PM ET by BG

1. 
   mauric6943 | Sep 10, 2003 11:06pm | #7

   BG - Thanks for the explanation.

   Mahogany versions may be ply b/c I haven't purchased the wood for the shelf bottoms. I have all the Lyptus already so will work with the suggestions you guys have provided.

   As for the back rise, long grain to long grain. Got it. But wouldn't there be a problem gluing to the sides. If the back is glued to the bottom AND to the side when the bottom expands, somehting has to give. Am I over analyzing?

   maurice

1. 
   BG | Sep 10, 2003 11:50pm | #8

   mauric,

   "As for the back rise, long grain to long grain. Got it. But wouldn't there be a problem gluing to the sides. If the back is glued to the bottom AND to the side when the bottom expands, somehting has to give. Am I over analyzing? "

   But if you put your glue on the back of the bottom shelf, inside the T&G, and let the rest of the bottom shelf float in and out with humidity..then all should be okay?

2. 
   eddiefromAustralia | Sep 10, 2003 11:02pm | #6

   Maurice,

   I'd anchor the front somehow and let the back move - the movement will be under the backboard of the shelf, so it won't be visible.

   I was originally talking about through housing joint(US dado), but a stopped housing does look neater.

   If you don't have a router bit to match the thickness of the bottom/shelf, you could go with a barefaced tongue and groove.

   Cheers,

   eddie

   edit:

   Yes, you don't glue the base in, it has to float to avoid cracking due to shrinkage.

   The other reason to anchor the front is simply structural.  The backboard holds your two sides together at the back.  The only thing holding the sides together at the front is the shelf - make sure that the shelf is securely fastened at this point

   Edited 9/10/2003 4:05:34 PM ET by eddie (aust)

3. 
   ron61 | Sep 11, 2003 02:37am | #9

   You say you want to use Lyptus with hand tools good luck its like working with Hickory.

   Who Ever Has The Biggest Pile Of Tools When You Die Wins

1. 
   TomFerreira | Sep 11, 2003 03:13am | #10

   Maurice,

   I would consider using a sliding dovetail along the cross grain connection to the sides. Leave it blind with enough room for expansion toward the front. I would then anchor the back to the base. this way you would never notice the expansion/contraction and the sides would be fastening to the base across the grain, by the sliding dovetail.

   TDF