I'm a total novice when it comes to wood working. I'm looking to
build a large shelf inside an 'entertainment center' that was built
into my house. The dimensions I'm with here are 60" wide by 28" deep.
The front, obviously is open. If I use planks for the top, what I
can I do to prevent it from sagging?
Thanks, guys! I really appreciate the quick responses! I'll give it
a try and see what happens!
Phisherman <[email protected]> wrote in message news:<[email protected]>...
> On 25 Sep 2003 15:13:10 -0700, [email protected] (Dan Wheeler)
> wrote:
>
> >I'm a total novice when it comes to wood working. I'm looking to
> >build a large shelf inside an 'entertainment center' that was built
> >into my house. The dimensions I'm with here are 60" wide by 28" deep.
> > The front, obviously is open. If I use planks for the top, what I
> >can I do to prevent it from sagging?
>
>
> Sixty inches is a large span. A 3" lip on the front and another on
> the back should provide some stiffness to the large shelf. But in
> theory, there will be some sag directly related to the load.
On 25 Sep 2003 15:13:10 -0700, [email protected] (Dan Wheeler)
wrote:
>I'm a total novice when it comes to wood working. I'm looking to
>build a large shelf inside an 'entertainment center' that was built
>into my house. The dimensions I'm with here are 60" wide by 28" deep.
> The front, obviously is open. If I use planks for the top, what I
>can I do to prevent it from sagging?
Sixty inches is a large span. A 3" lip on the front and another on
the back should provide some stiffness to the large shelf. But in
theory, there will be some sag directly related to the load.
"Dan Wheeler" <[email protected]> wrote in message
news:[email protected]...
> I'm a total novice when it comes to wood working. I'm looking to
> build a large shelf inside an 'entertainment center' that was built
> into my house. The dimensions I'm with here are 60" wide by 28" deep.
> The front, obviously is open. If I use planks for the top, what I
> can I do to prevent it from sagging?
Some ideas (you can combine some of them)
1) Use really thick planks
2) Run a cleat along the back that it can rest on
3) Build a "torsion box" - that is use fairly thin plywood for the top and
bottom surfaces and inside use some wood (say 1x2) on edge inside. This
gives a very stiff and light shelf. Depth is the key in resisting
bending/sagging
4) Put a support in the middle - effectively cutting the span in half.
5) Use very stiff materials - like steel.
6) Fill whatever is resting on the shelf with helium.
-Jack
"Dan Wheeler" <[email protected]> wrote in message
news:[email protected]...
> I'm a total novice when it comes to wood working. I'm looking to
> build a large shelf inside an 'entertainment center' that was built
> into my house. The dimensions I'm with here are 60" wide by 28" deep.
> The front, obviously is open. If I use planks for the top, what I
> can I do to prevent it from sagging?
You need to make the shelf as light as possible but as deep as possible with
as stiff a material as possible.
Make a fairly thin shelf, say about 1" thick and screw steel strips say 2" x
1/4" onto the front and back edges. Then cover this with wood, possibly the
same as the top. The key is in the depth. Without going into detail, double
the depth = 8 times the bending strength. Steel is best here as wood can
creep over time.
You may want to consider a strip of steel in the centre of the shelf as
well.
John
>
>Some ideas (you can combine some of them)
>
>1) Use really thick planks
>2) Run a cleat along the back that it can rest on
>3) Build a "torsion box" - that is use fairly thin plywood for the top and
>bottom surfaces and inside use some wood (say 1x2) on edge inside. This
>gives a very stiff and light shelf. Depth is the key in resisting
>bending/sagging
>4) Put a support in the middle - effectively cutting the span in half.
>5) Use very stiff materials - like steel.
>6) Fill whatever is resting on the shelf with helium.
Jack's suggestions are good ones. If you are going to put
anything even remotely heavy on the shelf, #3 would be the one to try.
If you're going to put something really heavy on the shelf, #3 is
still best but use larger lumber inside--or maybe steel.
Good luck.
Peter