Reaction to walnut

Bill

I have problems with edge alignment without something to help. Biscuits didn't.

Test scraps and a good table/lift.

Making two accurate passes is easier than one?

LOL ... check for those left and right arrows on anything I post. ;)

There are indeed a lot of cabinets in that album to look at.

Leon and I built and installed that particular job last year ...

Frameless cabinets have a challenge all their own, and it's a tough market to compete in because, with the precision and tolerances required, very few can afford to take their time and build each cabinet individually, then install them to meet the specs as we do ... they are usually mass produced, with very high equipment costs, which means many of those who do them often don't survive the inevitable ups and downs of the industry.

You gotta be brave, or foolish, or both to undertake some of these projects ... that, and a large measure of problem solving ability, confident optimism, and the tools to do the job, are just some of the things we both have in common that seems to gets r' done. :>)

I just came home with 2 selections from Half-Price Books:

Shelves, Closets & Cabinets, P. Jones, 1977. Success With Biscuit Joiners, A. Bailey, 2007.

I think I'm brave and foolish enough for my current project.

I've been thinking a "practice box" makes a lot of sense. I could practice my joinery and my finishing on it to help avoid more expensive surprises.

Bill

I see now that you were either being kind or being sarcastic by your use of the term "casework". : )

Yes, I liked that idea as soon as I read it.

I also like the idea of building a base frame--slightly smaller than the bottom, and floor-levelers.

I had been reading about biscuit joinery today, but now I see you prefer dadoes for the verticals over butt joints done with biscuits. I suppose you would attach cabinet face frames with biscuits, and use biscuits also to help align the bottom to the base frame, huh?

BTW, my wife told me today that she would prefer I make a new coffee table first. None of this will be wasted, however. I could use biscuits to afix some drawer frames to a coffee table. I could not of even written that statement a week ago, so I'm making progress! : )

Cheers, Bill

P.S. I'll probably work on the TV-stand first anyway. Relieved to find out they don't cost $1000 (like the jointer and TS I showed her at Grizzly), I sort of have her budgetary approval for a biscuit joiner--lol. I know she didn't know what I meant, but I told her I wasn't planning to buy a green one.

P.P.S. Something that has been troubling me the whole time I've been working on this post, but I didn't bring it up, was the fine line between a board fitting ornot fitting into a dadoe grove, particularly since I'll probably be cutting the grove with a router. Is there a decent fix for if the dadoe is cut just a little too wide? I know shims would look tacky, but no one would see them anyway and that would work, right? :) When you distribute "a little wide" over 16 inches or so, it doesn't seem like too much. Maybe I should take my humor over to David Letterman' Show? It's late.. :-)

(Same As Before)

Bill

I assume I make the "back" from the rest of the 1/4" plywood? Rebated-in, of course! A router table would be nice... even make-shift one.

BTW, in a similar model in a magazine, I noticed that they connected the ends of the top and bottom to the case with "tongue-and-dado" joints, rather than just rebates. Am I likely to accomplish that with a router? : ) Delivery of my TS is only a button-click away, but I keep postponing it, until I "really need it", or I (start and) finish painting! : )

Didn't you have a nice local cabinet shop supplier who could provide your cabinet-grade cherry ply rather than going through HD?

Here ya go.

? That's a new one on me.

Sure, that and a mallet and chisel, once you figure out how they've done it in the mag.

So put those higher on your To-Do List, Bill. I don't recall where you ended up in your shop makeover. (Electrical, drywall, prime, paint, and lighting would be the order of my list)

-- Every day I remind myself that my inner and outer life are based on the labors of other men, living and dead, and that I must exert myself in order to give in the same measure as I have received and am still receiving. -- Albert Einstein

Sagging furniture, a function of its span, is indeed a major consideration to take into account in designing and building casework.

I spent a goodly number of years noting and observing the effects of span on antique casework, and the historical attempts to mitigate sagging as a result of too great a span in furniture like sideboards and hutches.

Each time I ran across a wide antique piece I really liked, it seemed to suffer the ravages of sag due to its longevity ... drawers that no longer opened or closed fully, and doors no longer coinciding with their openings. This propensity for sagging was particularly apparent in those type pieces made in the Arts & Crafts period of the late 1800 and early

The obvious solution to sagging casework is to decrease the span, either by making the piece less wide, something that does not always lend itself to the preferred design, or by adding interim support.

One of the traditional ways to mitigate sag in these wider pieces was to add middle legs:

When I decided to design and build a wide sideboard to my own tastes, I totally discounted the idea of six legs. Not only did the addition of extra legs not fit in with my preferred style, it also increased the problems of situating a piece of furniture on floors that are not perfectly flat.

I did a good bit of research into the matter in the intervening years and it was not until I ran across an article in the Sep/Oct 1999 issue of "Fine Wood Working" magazine, by Will Neptune, entitled "Sideboard Strategies", whereby the author, a teacher at a respected woodworking school in Boston, taught/proposed a four part, casework construction method that was a bit unusual for traditional sideboard construction - basically a dovetailed box, turned on its side, with legs attached to the box, that I found a solution I thought I could live with.

In a nutshell, the basic principle of this particular casework construction method is:

"If a case part joins another at a corner, dovetail it; if one part meets along another's length, use multiple through tenons."

Since then I have used this basic principle, with some occasional modifications, in quite a few pieces of casework, both furniture and kitchen cabinets.

Careful studying the photos in the links below should give you an idea of how to use this principle to mitigate sag in your casework:

(If you can get a copy of the above mentioned article, do so ... it covers using this principle in many more styles than what I show above)

---------------------------------------------------------------------------------- Depends on the vertical height of the side and rear panels.

The larger the height value, the stiffer the box.

Some basic strength of materials.

I (Moment of Inertia) = (b*h^3)/12

For a rectangle

Where b = base; h = height

----------------------------------------------------- The larger the value of "I", the stiffer the beam will be.

The above is a very basic explanation.

For an in-depth explanation, construct a Strength of Materials engineering text.

Lew

----------------------------------------------------------------------------------

Are you saying that *sag* is related to a rotational force?

Concerning "sag", it seem like we should be measuring the distribution of mass between supports. If F=md is the force in the middle (of the horizontal beam) and it is low, then we should experience less sagging, right? The "trick" seems to be to make sure d is small. h appears to have little to do with it. Not being an engineer, I only have a very basic grasp of the concepts.

Please feel free to correct me, I like learning new things.

Cheers, Bill

...

...

Well, that's a moment of inertia, yes, but it's not particularly apropos to the problem at hand--that's I for a solid rectangle about it's horizontal axis of rotation. That really is not a good model for the casework problem.

The problem there is a combination of several factors including

joint stiffness -- that's what the article/construction methods address mostly

material properties -- wood isn't terribly stiff as compared to metals so w/ time it will droop if unsupported spans are too long or not sufficient material in cross section. It's that piece of (say) 3/4 face frame spanning an opening that is dependent on the above moment of inertia--as you're well aware, if you make a piece 2" wide it's much stiffer an will support more load than will a piece 1-1/2" wide (loaded vertically, piece on edge). That's the explanation for that particular part of the problem.

On a casework box, though, making it taller and looking at the penchant for the piece to sag between legs is more to do with how stiff the joints of the box are. The box is open to the face and so the sag is crossways, not lengthways that is significant so the aforementioned I isn't the right direction nor for the geometry.

hth...

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Thank you for your post. I haven't finished getting all of the meat off of the bone yet! : )

Bill

I was able to read a page and a half of the article online. Then I realized I owned the book I was reading out of (at Google books), Taunton's (Best of FWW): "Designing Furniture". I will read the whole article before the evening is over. Though, I'm not sure that my situation is like the one in the article because I'm using plywood. No one makes dovetail or M&T joints in plywood, right?

I found the picture of the sideboard at the link you posted above to be insightful

I was able to read a page and a half of the article online. Then I realized I owned the book I was reading out of (at Google books), Taunton's (Best of FWW): "Designing Furniture". I will read the whole article before the evening is over. Though, I'm not sure that my situation is like the one in the article because I'm using plywood. No one makes dovetail or M&T joints in plywood, right?

I found the picture of the sideboard at the link you posted above to be insightful

I didn't try him this time around, at least not yet. When I explained a while back that I wanted 1 sheet of Formaldehyde free (for my drill press), he wasn't too enthused. At least Rick (that's what I call him now), at HD, is nice. He was telling me about some of his projects. It may be worthwhile to try the lumberyard again... Thanks for mentioning it.

I got an error on that link.

It don't think it's "that" novel. You route a 3/8" groove on a side,

I'm basically down to my finish coat of drywall compound--1 wall down, 2 to go. Then I can prime and paint, etc. I've already got the paint rollers, etc., as I was hoping to get to that last summer.

----------------------------------------------------- Bill wrote:

---------------------------------------------------- The math confirms the following.

A 2by4 supported at each end will be stiffer if the 4" side is vertical rather than the 2" side.

The taller a vertical panel is the more "sag resistant" it is.

That's why the face frame is so important for case goods or the apron for a table.

It is also why 1/4" plywood panels nailed to the studs at the corners of a building makes the building far more earthquake proof.

Lew

Now, I appreciate the clarity of that explanation! : )

I learned, at least, that I'm not going to undersize my face frame!