Latest Discussions : Tools & Workshop

Woodbe

07:50AM | 05/03/03
Member Since: 05/02/03
Since I can't buy one ready made, I am going to try to build a picnic table. I know this is probably dumb, but I can't quite figure the best way to nail the top boards to the 2x4 cross pieces on the underside and still end up with the thing being square! (All the plans say to assemble the top first by nailing thru to the cross pieces) There has to be an easy trick to this, but I don't have a clue what it is! Have thought that maybe I should start with the two outside boards, get the thing square then work in to the middle? BTW, I am still looking at plans and thinking about the process...have not yet made the first cut! I would rather have no table than have a crooked one!

Altereagle

08:55AM | 05/03/03
Member Since: 12/27/02
Use the 3-4-5 method (The Pythagorean Theorem) from corner to corner as a final check.

3' on the backer, 4' on the top board then 5' on the angle from 3' point to the 4' point makes the first board square.

For a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides: a2(3) + b2(4) = c2(5)

From there you can measure for the rest then at the end measure from corner to corner (they will be equal) and adjust.. you'll have the squarest picnic table on the block.

Mark Hammond

01:22PM | 05/03/03
Member Since: 05/09/01
Hi Woodbe,
You can try this simple trick. Nail a jig or form to a flat surface like a piece of 1/2-3/4 inch plywood laying on the floor. The pieces can be 2x2 inch stock or really whatever you have lying around that have the length that you need. Using a framing square on the corners to lay it out. It will have to be the size of the top of the table so that the top will fit inside. Four pieces to form a rectangle in the dimensions of the top. Use the square to get the angles on the corners right. Lay the pieces for the top, bottom up, in the jig with the correct spacing. Then you can lay the cross pieces in place (again using the correct measurements to position them and the framing square to get the angle right). Use whatever fasteners that you choose (galvanized screws work well) and a waterproof glue on the cross pieces. Let the glue set to give the top some ridgity and then fasten the legs as the plan suggests. Good luck and enjoy the picnic.....MJH

Woodbe

02:33PM | 05/03/03
Member Since: 05/02/03
Hmmm...OK. I was thinking I needed to screw or nail the boards from the top side into the cross pieces below, not the other way around, and I figured that was going to be next to impossible and still keep everything square. I suppose I could do as you suggested but just use the glue, then when it is set, flip it over and nail it. Thanks for the suggestions!

rpxlpx

08:05AM | 05/05/03
Member Since: 03/13/00
I think you'll be happier with screws than nails, especially if you will sometimes move the table. Nails work loose - screws don't.
Also, I recommend stainless, rather than galvanized screws if you want it to last without any rust.
One more thing: a simple way to get a square angle is to use a sheet of plywood as your guide. They are square when you buy them. Lay the pieces onto the plywood on the floor/ground.

Altereagle

03:26PM | 05/06/03
Member Since: 12/27/02
Ya, I too thought of that simple ply thing after I posted.. still it's good to check with the basic math...

You know I always use electroplated fasteners, but read in a book just a couple of days ago zinc coated is better.. I, like you rp, haven't found that myself, I find the zinc get's knocked off easier especially with gun nails... hmmm? Goes to show you got to take everything with a grain of salt huh?