Do I need biscuits?

[Jeb Sawyer]

Rather new to woodworking, so this may be a simple question. I'm making a tabletop out of 1" cherry on top of 1" MDF. I am going to band the table top with cherry also to cover up the MDF. My question is where do I need to put biscuits? I am glueing together 5 pieces of cherry for the top, but since it is long grain to long grain is there still a need for biscuits. And what about the banding on the sides (with grain running perpendicular) should I be concerned about the wood expanding and cracking?

Any suggestions would be much appreciated. Thanks, Jeb

[Brian D. LaVoie]

In my opinion biscuits will do little more than help with alignment in a long-grain to long-grain glue joint. The glue alone will create a very strong bond, provided your joints are nice and tight/gap free, and thus I have never seen the need for them.

Since edge joining the 5 boards for the top is long-grain to long-grain orientation, as will be the edge banding (face grain is also long grain), I'd skip the biscuits and just use a good glue like Titebond (or Gorilla if your interested in poly glues).

*However* -- Your description is not entirely clear with respect to how the MDF comes into play. I got the idea that you are planing on "laminating" the cherry glueup on top of a MDF panel of equal dimensions???? If so, this is a no-no, as the cherry will be robbed of its need to expand and contract across its grain with changes is seasonal moisture. If the MDF panel is somehow integral to the design (which I can understand why -- maybe you can give us more detail into the piece you are planning), you'll have to figure out a way to attach it that will still allow movement of the cherry panel, which obviously precludes you from gluing the edge banding to both the cherry and MDF as well.

Clear as mud??? LOL. Give us somemore detail as to the table design, and its intended uses and we can get you rolling in the right direction. Likely the 1" cherry top will suffice on its own, and with a properly constructed apron & leg assembly will be very solid. If a thick appearance to the top is what you desire, the wider edge banding can still be applied to be flush with the tabletop, but extend below the bottom edge.

Hope this helps. Good Luck -- Its a great hobby. Welcome to the group.

[Brian D. LaVoie]

Oops! I meant *can't* understand why, here. \/\/\/\/\/

[HarryM]

Don't glue the cherry to the MDF unless you are building an arch. If the humidity goes up, the table will cup upwards as the cherry expands and the MDF doesn't -- downward if it dries out. If you must use the MDF, use screw slots and omit the glue. Believe me, I did this once with a red oak table and it bowed a good two inches in the middle. The customer put the table in a room with about fifty house plants which she watered daily. I had to practically rebuild the table. harrym

[Nut Tree]

Only if their hot and you have fresh honey.

[Jeb Sawyer]

Glad to know that what I was going to do is a big no-no before I actually did it. The reason I was planning on adding the MDF is to increase the rigidity of the table top as I am building it as a desk for my girlfriend and I have some reservations about 1" cherry being able to handle the weight over time and not bending in the middle. But this once again could be my own naivete.

Also, a quick clarification. Are you saying that even on the edge banding (where endgrain will be joined with long grain) that I don't need biscuits there either?

Thanks again for your help, you are saving me many headaches and a lot of money in wood.

-jeb

[Luigi Zanasi]

On 14 Jul 2003 21:48:06 -0700, apt [e-mail] (Jeb Sawyer) scribbled

The MDF is a no-no, like the others have said. Check out the "sagulator" to see if your 1" will be enough. If it is, or there is little sag, then adding the edging will add suspenders to your belt. :-)

"no" with "yk" twice in reply address for real email address

[McQualude]

Jeb Sawyer spaketh...

Brian already answered your other question, let me add that 1" cherry will be plenty thick for for a desk under normal loads, the MDF won't be necessary.

I'll also say that although the biscuits aren't necessary, they will make glue up much easier and getting a good glue up will make finishing much faster/easier. If you have a biscuit joiner, use it; if you don't have one, don't buy one.

[Brian D. LaVoie]

Jeb,

You are correct. The edgebanding will be OK on what I will assume will be the longer dimension of the desk, i.e. long-grain to long-grain orientation. But as far as the end grain of the cherry top, an edge band would pose a cross-grain problem and should be avoided, as it (like the MDF we spoke of) will prevent seasonal movement of the cherry.

If you are intent on covering up the end grain of the cherry top, consider using breadboard ends, which allow the panel to move as it needs. Check out the "Projects Gallery" on my site below for an example of breadboard ends on a cherry table with a 3/4" top. Conversely if what you really want is an edge banding all the way around the top to give it a look of thickness, i.e.

2 inches, then you may want to use a cherry veneered plywood panel instead of the hardwood as it would not expand and contract, thus eliminating any cross grain concerns.

-- Brian

"laminating"

[Jeb Sawyer]

First off, thanks to all who posted, it's nice to not have to rebuild a piece too many times. Secondly, my initial plan for the desk has been scrapped (although I am still planning on building the tabletop according to the above recommendations). So, my question is: can you point me towards a plan for a basic desk (by basic, I eseentially mean that I want a table, with perhaps one drawer in the front apron). Break down assembly would be nice as it will be going around a rather tight corner. Thanks again for your help, jeb

Quick question: Do you really think a 1" (3/4 actual) cherry table top would look ok. Seems kind of chincy to me.

[McQualude]

Jeb Sawyer spaketh...

It depends on what 'look' you want. Also, if you can buy 5/4 or 6/4 cherry instead of edgebanding.