Rain Cover for a pit

[Ste1978]

Well, here's a good one. I've been given a task from a training book as follows:-

create a basic 3D sketch for a rain cover to fit over a large pit!

Outside Dimensions 26m x 9m split into 5 bays

Height to the eaves will be 1.5m

Pitch of roof 10 degrees to apex

5 rows of purlin rails each side

Please show cladding on roof (grey or white)

You can show some typical bracings if you like...


ok, I'm not asking anyone to do this for me, but I just can not visualise how this should look. Does this make any sense to anyone?

[kencaz]

Probably something similar to this: Much smaller of course.

[Ste1978]

Thanks Kencaz, I guess the 26m is the length of the 5 bays combined, and the 9m is the width of the rain cover. The horizontal beams across are the perlins. I suppose the height of the rain cover can be worked out using the 10° to the apex. What would be the braces? Are these the supports holding the beams? Sorry, I'm not a mechanical engineer!

[kencaz]

The perlins are on top of the Rafters (yellow beams), and support the roof, (cladding in your case). The bracing would be the supports holding the perlins to the rafters. The bay's would be the area between the rafters, so you would need 6 rafters to get 5 bay's

I think that sounds about right.

KC

[JD Mather]

... from a training book as follows...-create a basic 3D sketch

I would use 2D sketches and Frame Generator. I see too many people fight with 3D sketches for something like this. 3D sketches have their place - this design is not one of them.

I decided I might use 3D sketch for part of the design, but
even if I were to use a 3D sketch for this design I would use 2D sketches to set up and control the 3D sketch.

[Ste1978]

I would use 2D sketches and Frame Generator. I see too many people fight with 3D sketches for something like this. 3D sketches have their place - this design is not one of them.

I decided I might use 3D sketch for part of the design, but
even if I were to use a 3D sketch for this design I would use 2D sketches to set up and control the 3D sketch.

Yeah, good point. I've already decided to use the frame generator. The use the sheet metal for the cladding. I'll upload what I've done when I'm finished if anyone is interested/wants to laugh at my efforts!

[pinco pallino]

No one should laugh at it.
I designed a few of these sheds and can be an interning challenge.
KC, did you design that one on the picture?
Bloody good work.
As for the bracing I think it refer to the diagonal strapping placed to prevent twisting of structure.
The purlins are attached to the beams by cleats.

[kencaz]

I found it easier to just sweep a beam profile for a single rafter then add a rib support.

Then just inserted and constrained the beams in the assembly. Add some corrugated roofing and siding and your pretty much done.

rafter.jpg

shed.jpg

roofing.jpg

Don't forget the railing around the pit.

KC

[Ste1978]

That's excellent kencaz, I might give the sweeping a try. I didn't think of that. My first effort looks like this so I'm not a million miles away, although I'm been advised to add diagonal bracings. I guess the cladding will go all the way down around and down the sides of the building too to stop rain coming from an angle.

How did you create your cladding? Did you do this in sheet metal or was it just a sketch you extruded?

[kencaz]

How did you create your cladding? Did you do this in sheet metal or was it just a sketch you extruded?

I arrayed a simple profile to get the width I needed for the panel then extruded for the length. Use a standard sheet size.

roof1.png

roof2.jpg

I'm sure you could do it in Sheet metal as well but I did not try that yet.

KC