Edge joints in case back boards

[klkirkman]

I am looking for information on the alignment ( vertical versus horizontal)  and the way to make joints ( butts, half laps, tongue and groove, etc )  between the individual secondary wood boards that make the back of a case piece. In particular, I am wondering how they dealt with  the difference in expansion rates between back  boards that were tenoned into sides if the grain in the back was  perpendicular to the grain in the sides.

Karl

 

[Antiquity]

Karl,

For a bookcase the back boards are usually set into a rabbit.  It is best to use a T&G joint with a space between them, say 3/32-1/8".  I nail the boards into the rabbit and glue just the center edge into the rabbit.  This way the board will expand and contract from the center only.  If you use a half lap joint the boards can eventually bow and then you will not have a tight joint (I speak from experience).  Run the back boards horizontally as this will keep the sides from bowing outward.

Dennis Bork
Antiquity Period Designs, Ltd.

 

[Adam Cherubini]

I always thought the backer boards attached the tail boards together.  The pin boards can't pull out.  So that would explain the orientation of the backers.  I'm not sure that's always the case on period furniture.

The backs of some of the really fine Philadelphia cases look like packing crates.  Its hard to believe the guy who made the front could bring himself to do such a poor job of the back.  (and some of have speculated that they were two different people, tho I'm skeptical)  I don't recall seeing any edge joints- t&g or half lap.  Now obviously the backers have shrunken after all these years;  Gaps between the boards are fairly typical.  I don't recall seeing glue in those gaps and it doesn't appear that they fit particularly well in the first place.
 
Backer boards were typically nailed into rabbets. I don't know about glue on originals I've seen.  Splits around the nails are not unheard of.  Though I recall seeing pretty sound backs. (I'm just going by memory here)

What's funny is that the boards that make up the back don't always have parallel edges (drawer bottoms too) so you see these boards butted together looking like crooked teeth.  Clearly, in Philadelphia they went to no extravagance with backs.

Can we bring oursleves to mimic this work?  Will our customers accept this?  What is an responsible or appopriate way to make and attach backer boards? How prevelant are the "packing crate backs that I've described here?  All good questions, and I'm sorry I don't have any answers.  I'm trying to think if I have any pictures for you. 

Adam

 

[rdare]

Adam,

The "packing crate" backs that you describe were the rule rather than the exception. Even the vaunted Goddard pieces look like they were hacked together from the back.

Considering that flattening timber was very labor intensive, and therefore expensive, pieces which were intended to go against a wall received little attention on the reverse. Your patron was only willing to pay for refinement on the areas which his guests could see.

As to whether that would fly today, I guess that would depend on your client. Does he/she want an exact reproduction or a piece of modern furniture that looks like the original but which is finished inside and out.

Dick Dare

 

[Adam Cherubini]

Dick,

My experience is that many woodworkers, includng some reproduction furniture makers, have trouble believing this.  There's no question in my mind (because it's happened to me and I've done it myself) that furniture owners don't want the shoddy sides of their pieces photographed for financial reasons. 

When I look at period furniture, I'm continually struck by how bad it really is.  For me, that makes me feel better as my furniture starts looking okay by comparison!

Seriously, I DO find it interesting that people like us can look at a piece of furniture and see a record of someone's decisions and values.  Maybe for that reason alone I love to see the little contradictions so prevalent in pieces from this period.  I don't find such things inferior.  Indeed, I think this is an aspect to period furniture connisseurship that has escaped some clever furniture dealer.

Adam

 

[dkeller_nc]

"I don't find such things inferior.  Indeed, I think this is an aspect to period furniture connisseurship that has escaped some clever furniture dealer."

Agreed - You've had the chance to examine a heck of a lot more colonial period furniture than I have (for which I'm jealous!), but even to this neophyte it's very interesting that I can walk into some of the local collector's homes and instantly spot the difference between a colonial - period piece of furniture and one made during the early 20th century.  Some of these 20th century repros have an exterior "show side" surface that's just as scuffed, worn, and dirt-encrusted as some of the originals, but the absolutely regular joints, moldings, and dimensions are dead give-aways, and so far as I've seen, the backs of these pieces of furniture are just as smooth and regular as the show side.

The interesting thing about this is that I've struggled to reproduce the secondary and tertiary surface characteristics of colonial pieces.  It's not that I don't have plenty of rough boards to use for the purpose, it's just hard to make myself consciously avoid spending time making tight-fitting joints and taking the smoothing plane to the backboards.  That's 20th century training coming through - no doubt the colonial makers did it as a routine matter of course - they would've had to consciously make themselves clean up the secondary and tertiary surfaces.