Simple Y/N question

[Chris Fougere]

I am planning on building a case with a base that measures 76" wide. Do the rails need extra support? I was planning on laminating two boards together to have rails 1 1/2" in width. They will be floating mortised in to 2 1/4 square legs.

Thanks.

[Quinn McCarthy]

Youo are going to have to be a little more specific. Is it a built in case or stand alone? WHat kind of wood are you using? Are you talking about gluing together 2 pieces for the bottom rail?

Sorry about that.

Quinn

[Mike Cruz]

I would say yes right off the bat. But the more pressing issue is good luck getting a simple yes or no out of this group. :D

[Chris Fougere]

Youo are going to have to be a little more specific. Is it a built in case or stand alone? WHat kind of wood are you using? Are you talking about gluing together 2 pieces for the bottom rail?

Sorry about that.

Quinn

Bottom rail is a lamination of QSWO and white oak.

It is built into a case. There will be a 50lb plasma tv on the stand.

[Chris Fougere]

This thread has the rough design of what I am trying to build:

http://www.sawmillcreek.org/showthread.php?t=121642

[Cliff Rohrabacher]

That all depends. Weight, density, coefficient of friction, thermodynamic properties of the atomic structure, dielectric resistance, and whether ya got any beers.

[Mike Cruz]

What did I tell ya? :D

[Bill Arnold]

I would say yes right off the bat. But the more pressing issue is good luck getting a simple yes or no out of this group. :D

What did I tell ya? :D

OK, so what is the answer? You criticize others for not providing an answer when no information has been provided but you don't offer any type of answer yourself! :)

[Chris Fougere]

What did I tell ya? :D

A little surprised actually...

[Jim Rimmer]

Yes, if it works out.

No, if it doesn't work out.

:D

[Chris Fougere]

Lots of comedians it seems, that's too bad. There goes my belief that most strangers are inherently helpful....

[Rob Fisher]

Lots of comedians it seems, that's too bad. There goes my belief that most strangers are inherently helpful....

You are asking a difficult question and expecting a simple answer. Of course you are going to get some joking responses. On top of that you have provided incomplete information.

But I will try to answer your question as best I can.

It depends. You say the rails will be 1 1/2" wide but how tall will they be? Are these the rails in question only at the bottom of the case? (I am assuming they are.) Will the bottom have any pieces that go from the front rail at the bottom to the back rail at the bottom? Will you make the bottom a torsion box type construction?

Also, regarding the 50 lb plasma TV, I would make sure the weight of the TV (and any other weight that will be place on the top) is supported by the rails that hold the top of this piece. Is the top supported in any way other than at the edges? Like is there a subtop or will it be torsion box type construction?

I think it is possible that you could construct this piece in such a way that there would be no other supports needed for the rails. I would probably use a torsion box type construction for the top and bottom horizontial surfaces and make sure that your rails are deep enough to support your expected weights without sag. You could also build intermediary legs near the center of the piece so that they would not be seen at the front edge.

If you would provide a section of how you intend to construct this piece it would be very helpful to this discussion.

Rob

[Myk Rian]

OK, so what is the answer? You criticize others for not providing an answer when no information has been provided but you don't offer any type of answer yourself! :)
Mike did provide an answer. He answered YES to a yes/no question.
Did you really read his post?

I would say yes right off the bat.

[Rick Moyer]

To get back on track here: Chris, you ask for a simple yes or no answer to a question that has too limited information to qualify a simple answer. You shouldn't be disappointed when you in fact got a simple answer. Unfortunately, sometimes simple asnwers are not the best answers. If you really want some reasonable reponses to your question, you're going to have to give more details on what you are trying to do. (I see you referred to another thread. I'm sorry I didn't see that when posting this.)

[Mike Cruz]

Okay, this is EXACTLY why I posted what I did in my first post.

It is not a simple yes/no question. I FULLY understand why you asked for one, believe me, but there are WAY too many people here that understand architecture and weight bearing factors WAY too much to give a simple yes/no answer.

I said yes, you need more support for two reasons:

First, I almost always over build. I love making a project...I HATE re-doing a project. So I would rather over build at look at something that "might" be a tad bulky than see a sag 3 months later;

Second, I don't have the architecture background to figure out what the load capacities on your specified dimensions are. I go by what my gut says, and if I were building what you are building, I would give it more support.

I built a bridge over a creek on my property (well, two, both the same). Did I KNOW that five 2 X 12 X 12's with 2 X 8's across them (okay, there's a little more to it then that) would support not only horses crossing it, but my JD 4500 with front end loader full of gravel and a bush hog on the back? No, but my gut said yes. Those bridges support (with said above weight...about 7000 lbs) the tractor without so much as a wiggle.

I know, I know, I took a risk. But I was confident in my gut.

So, back to the question. Yes, I think you need more support. Do you HAVE to? No, it might not sag. You might be okay. Do you want to find out later that you should have put in a support?

The other posters that say they need more info are, in my opinion, trying to be more critical/acccurate with their answers. They may or may not know more than me. I don't know them, so I can't say. But if you give them more info, we will all find out what they do or don't know.

How's that for not giving a simple yes/no answer?

Oh, BTW, thanks Myk for responding EXACTLY what I was going to say. ;)

[Frank Drew]

Chris,

It's better to be safe than sorry; doubling up on your bottom rail is a good idea, considering the span your considering. Another idea is to screw a piece of stout angle iron into the inside corner between the underside of the bottom shelf and the back of the front rail; firmly screwed into both members, it should give you a good deal of sag resistance, and no one would ever see it.

[Mitchell Andrus]

I am planning on building a case with a base that measures 76" wide.


ANYTHING that wide needs central support, even for it's own weight alone. A 50# TV... plus cable box, DVD, vase filled with water, stacks of books inside. I'd also plan on another 250 pounds for when someone uses it as a platform for changing that bulb in the ceiling.

I seem to remember a site with a deadload, pounds/foot standard used by furniture designers. Anyone know of it?
.

[Chris Fougere]

Thanks all, this is great information.

Unfortunately I don't know how I am going to build it. I was unable to find any plans for an entertainment center this wide in the craftsman style. In my design thread I referenced earlier there is a diagram of what I am trying to build. So far all I have done is mill the 2 1/4 inch legs.