Structural question?

[glider]

Doing some mock up before I cover the wall. The plan is a 9'x22"x3" slab of wood mounted below the window. I will adjust the framing and use some angle securing to the wall and one side. The pipe is 1 1/2". There is three supports but the center support is just the upper half. How sturdy is this going to be?

View media item 81046

 

[dfiler2]

So a 3" thick x 22" x 9' piece of wood with one support at midway. I think it needs a center bracket the same as the ends. Of course a lot will depend on the species of wood and what it's being used for. I really like the brackets and the whole idea.

 

[NUTTSGT]

What type of work are you planning on doing on this bench ?

 

[ddawg16]

The ends will be real strong....if you do the center as you described, it's not going to do much for you.

If it was me, I'd run a 2x4 under the back of the table and anchor it to the wall. If the slab is in fact 3" thick....that ***** will be pretty strong. But, personally, I'd make the bottom leg of you 'bracket' go down a little closer to the floor. And I'd make sure the top is really secured well. If you know for a fact exactly where it is going....maybe install bolts from the backside of one of the boards so you can bolt the 'bracket' to it at the top. The bottom will be in compression...the top will be trying to pull away.

 

[kbs2244]

I never like to see NPT used in tension.
The taper makes it all wrong.
Your shown design makes up for that by putting the bottom joints in compression
Use the same design in the middle

 

[gahrajmahal]

The weak spot is the middle of the window area. I cannot see the studs for the window opening but I assume with 2 x 4 king stud on either side, a single 2 x 4 jack stud next to that. Under the window a double 2 x 4 sill and cribbing from window sill to mud sill. You could reinforce it with some steel angle.

Is this your workshop or the inside of the house?

 

[glider]

What type of work are you planning on doing on this bench ?

This is not going to see much work. Finished piece of Hickory with a live edge, few bar stools.

The weak spot is the middle of the window area. I cannot see the studs for the window opening but I assume with 2 x 4 king stud on either side, a single 2 x 4 jack stud next to that. Under the window a double 2 x 4 sill and cribbing from window sill to mud sill. You could reinforce it with some steel angle.

Is this your workshop or the inside of the house?

This is my workshop.

 

[glider]

This is what I was copying.

 

[matt_i]

I think its going to be as strong as the upper attaching screws can be. It looks like the pipe flange almost splits between two face-members which could leave a weak screw pocket close to the end-grain of the cut. The more that I look at it, I think the short vertical 2x4 on the flat is also going to be a weak link. That should be solidly screwed into framing directly behind. Ideally at least one screw thru the pipe flange should go all the way thru the face and rest in the framing behind.

I agree a mid support is a good idea for a 3" x 22" piece of hardwood. It could be a weldment or a flat bar folded into a triangle that's lower profile than the ends so it "hides" better.

Looks like a great interior and a really nice view out as well!

 

[dave_dj1]

You will be just fine as long as you don't put more than say, one, maybe two exotic dancers on it at one time! A piece of Hickory 3" thick and 9' long won't need any center support for a simple bar top. I would make sure the two end supports are in about a foot from each end thereby making the span even less, you'll be fine.

 

[NUTTSGT]

This is not going to see much work. Finished piece of Hickory with a live edge, few bar stools.

Ahh, my concern was if it was a workbench and maybe some heavy duty use that the weak point of the cast flanges could fail resulting on it being in your lap and you on the floor.

 

[matt_i]

Just another thought...I feel like the Sch40 pipe and its threads can hold 300 psi reliably, with probably a safety factor of 2. For 1-1/2" nominal ID (1.767in^2) @ 300psi => 530 lbs axial load if used as a pipe system holding pressure. With my safety factor I would WAG the pipe can handle 1000 lbs of "dead" axial tension...however asking wood screws to hold that in tension is a little scary.

 

[glider]

With a piece of angle on the wall supporting the wall edge. Also keeping the bar from pulling away from the wall. With weight on the front edge of the bar. Is that transferring the weight towards the wall at the lower wall mount?

 

[TractorJeff]

I don't know?
Looks like a "Deer Sniper Bench"
LOL!

 

[memphisnate]

To reduce weight, you could always carve out (router?) some of the underside wood while still preserving the live edge. Likely take out 30% of the weight without losing any functionality or looks...

 

[joe_padavano]

The ends will be real strong....if you do the center as you described, it's not going to do much for you.

^^^This.

I never like to see NPT used in tension.

You do realize that if the pipe has pressure inside of it (like a steam pipe), the NPT is in tension, right?

 

[lakeroadster]

With a piece of angle on the wall supporting the wall edge. Also keeping the bar from pulling away from the wall. With weight on the front edge of the bar. Is that transferring the weight towards the wall at the lower wall mount?

Yes, the weight on the wooden slab will transfer through your pipe brackets and push against the wall at the bottom, but will be trying to pull the bracket out of the wall at the top.

That's why the angle is a great idea, attached to the wall and to the underside of the wooden slab counter top.

That takes much of the stress off the screws in the top pipe flange.

Looks like a neat project.

 

[kbs2244]

"You do realize that if the pipe has pressure inside of it (like a steam pipe), the NPT is in tension, right? "

Very true

But internal PSI is very different then external pull.
That is why the codes call for all the many kinds of pipe supports they make.

 

[BADSIX]

With a piece of angle on the wall supporting the wall edge. Also keeping the bar from pulling away from the wall. With weight on the front edge of the bar. Is that transferring the weight towards the wall at the lower wall mount?

do this and you'll be golden! now get the dancers.
really like the pipe concept nice job. BE SURE TO POST A COMPLETED PICTURE.
Jay D.

 

[GMCGarage]

I never like to see NPT used in tension.
The taper makes it all wrong.
Your shown design makes up for that by putting the bottom joints in compression
Use the same design in the middle

I think at a min the steel is 48KSI steel for that type of pipe.

 

[Captain Spaulding]

I'd be afraid that vertical 2x4 at the end will be a weak spot. It looks like it is just toenailed in place, and it also looks like 3 of the 4 holes in the flange are going to be over it. Weight down on the surface will be trying to pull that upper flange off the wall and I don't see that 2X4 doing much to help stop that from happening.

 

[glider]

I'd be afraid that vertical 2x4 at the end will be a weak spot. It looks like it is just toenailed in place, and it also looks like 3 of the 4 holes in the flange are going to be over it. Weight down on the surface will be trying to pull that upper flange off the wall and I don't see that 2X4 doing much to help stop that from happening.

I will be doing the adjustments to the framing.

 

[joe_padavano]

"You do realize that if the pipe has pressure inside of it (like a steam pipe), the NPT is in tension, right? "

Very true

But internal PSI is very different then external pull.
That is why the codes call for all the many kinds of pipe supports they make.

Tension on the threads is still tension on the threads. I understand that tension on the threads while under internal pressure does increase the thread holding, but it does nothing for the shear forces in the thread roots. That will be the same under either load condition.