and now Flexner has confirmed (in my mind) why it's not needed.

@Fred W. Hargis JrCannot get the link to work

Let me try again.

 

Crap, I can't get it to work: cut and paste, I guess.

https://www.popularwoodworking.com/article/finish-both-sides-is-it-necessary-to-do-this-or-not/

On the tables I build, when the stain and finish go on...table is sitting on it's top, legs in the air.    I work down from the bottom of the legs, and even stain and varnish the underside and the insides.   I leave the top's edges alone until I turn the table right-side up....do the top, and then clean up the edges. 

 

Necessary ?   No...until one realizes people will be looking under the tables.    Most of the ones I do, are small enough one can be carried around...either by the legs, or they get turned over, and carried by the top....and peoples' fingers will go along under a top, as much as across the top.  

 

Just presents a more "Finished" job.

Totally unnecessary and a waste of time and finish?? Not on my tables! 

I agree with Bob. It is not necessary to finish bottom or inside. I might apply shellac to the inside of drawers if intended for clothes,but nothing else. All that furniture made over 100 years ago they did not even smooth the unseen areas that would be labor intensive. Ok maybe 200 years.

This subject has been a lively one on a another forum. While I agree that finishing the underside of a table might be important for esthetics, I think Bob's point is that many do it for the "protection" aspect; and that's the part that's unnecessary. I think a lot of of us skip the underside more than we think. For example, I've never finished the underside of a top for a dresser or other type of cabinet before I assembled it.

 

PS, does anyone know why I can't get that link to work...I've done links before and never had this problem.

I even finish the backs of book cases and cabinets. Heck, ya got the spray equipment out, why not? 

And if you are brushing, just slop er on, thats the fun part.

Herb

Edited October 10, 20187 yr by Dadio

I yam cornfused.  I thought that cupping (on a top, per photo) would be due to drying out, the departure of moisture causing the grain to shrink.  It seems non-intuitive that adding moisture causes that face to shrink. 

 

Just googled it:  the internet thinks moisture makes wood swell, not shrink.  So that must be true because it's the Internet.

 

Bonjour.

Edited October 10, 20187 yr by PeteM

I believe that finishing both sides will give both sides the same qualities and therefore keep the top straight.  Seems to me if the bottom is left as bare wood it can absorb more moisture than the top causing it to cup because the wood does swell when moisture is added.

I will jump in with both feet, You don't finish the underneath of wood flooring and it doesn't warp unless it is flooded,and that is only because the water is trapped under the floor and the underneath can't dry out as fast as  the top does.

Just saying,

Herb

I'm still working this link thing...let me try again:

linky

 

SUCCESS...don't know why it didn't work above.

Edited October 10, 20187 yr by Fred W. Hargis Jr

45 minutes ago, Fred W. Hargis Jr said:

I'm still working this link thing...let me try again:

linky

 

SUCCESS...don't know why it didn't work above.

 

Yes.  It does work now.

As to the finish slow adsorption you would have to have the same number of layers top and bottom. DO you do that or just apply a seal coat????

1 hour ago, Dadio said:

I will jump in with both feet, You don't finish the underneath of wood flooring and it doesn't warp unless it is flooded,and that is only because the water is trapped under the floor and the underneath can't dry out as fast as  the top does.

Just saying,

Herb

I'd be willing to bet the floor would warp under those conditions even if it was finished.

In commercial construction it was quite common for 3'X10'X 1 3/4" office doors to have a warp, and we would have the painter spray the opposite side with a coat of lacquer,and they usually flattened back out. They were factory prefinished doors.

 

Herb

1 hour ago, Fred W. Hargis Jr said:

I will jump in with both feet, You don't finish the underneath of wood flooring and it doesn't warp

 

Hardwood floors come in 3" wide pieces so they lay flatter.

@kmealy hasn't been around for over two weeks.  On vacation I hope.

1 hour ago, HandyDan said:

 

Hardwood floors come in 3" wide pieces so they lay flatter.

I've installed a couple floating floors, hardwood (and 3"), and the instructions are very clear to underlay the flooring with plastic sheeting to trap moisture away.  Would laminate flooring be something like plywood, more resistant to moisture effects?  I usually coat the "offside" of any finished wood with a quick 1-layer seal coat.  Doesn't hurt, might help.  Gotta get the finish off the brush somewhere.