Need tips building a 30 ft wooden octogon

[CapSmashy]

The technical name is waferboard, though most call it chipboard.

Particle board looks like mdf and is made of sawdust.
None are treated, as fencing is.

I thought the name was OSB: Oriented Strand Board

What is pictured is OSB. OSB differs from wafer board in that the wood strips utilized to manufacture it are mostly rectangular and woven/laid in mats in cross oriented layers to give it structural rigidity. It has replaced plywood in most construction applications as it can sustain higher load pressures and is significantly cheaper to manufacture. It is bonded together in the same manner that plywood is with a mixture of mostly wax and resin based adhesives. Composition of the material is approx 95% wood and 5% wax and resin. The wax being pressed into the wood during manufacture imparts a fairly substantial amount of moisture resistance and exposed OSB will last for several years with no significant loss of structural rigidity unpainted and exposed to the elements.

Wafer board is essentially nothing more than particle board except it utilizes wood chips instead of sawdust. Both are made in the same manner as OSB in terms being pressed and formed into the proper dimensional finished product. It is used primarily in the manufacture of cheap furniture that has a laminate finish. Wafer board has largely replaced particle board because it is lighter with the same amount of strength and it is not suitable for any kind of significant, load bearing construction since it's strength relies on glue and it has little, if any, moisture resistant properties.

In terms of burning OSB as part of an art installation, it is no different than burning non-pressure treated plywood.

[CapSmashy]

I've seen osb too.
Home depot told me they purchase it under the name waferboard.

Home Depot sells both OSB and wafer board.

It's all crap.

No it isn't. OSB is structurally stronger than plywood for a third the cost. It is also significantly more environmentally friendly than plywood since it can be manufactured from the wood scrap produced from making dimensional lumber.

[gyre]

Thanks, Smashy.
I'll look into that.
I tested a sheet with a sledge and wasn't impressed, but perhaps I should take another look.
There is a definite cost advantage at the moment.

I recently got a lot of laminated sheets, many mdf, some a composite of some sort, laminated.
Seems quite stiff and light.
I'm using it as decking on racks.
I've avoided using the pressboard so far, but I've got a bit of it and the laminate gives them some strength where there isn't water damage yet.
I'm still getting splinters out.

I'll check into osb more.
Do you really consider it superior?
To exterior grade?

[CapSmashy]

It of course depends on application. There are going to be some where thick exterior ply will still be superior such as when you need to span a horizontal surface that is not on 2 foot centers. OSB has a higher vertical load strength.

In terms of general construction though, I find OSB to be equal to ply in every respect for pitched roof decking, sheathing, etc.

[chiefdanfox]

you can call me.
510-612-0664
or
[email protected]

I have lots of info. think about buying a bunch of ratchet tie-downs at HD or Lowes. 10,000 lbs per(~$15), using ground anchors (org will supply). You can mitigate incredible wind loads. We were good to UBC loads (125 mph). Anywho, I was the Anubis artist and we had a 50' high structure that was basically a flexible tower. Dan Swain came up with the ratchet tie-downs, and it saved our bacon.

The ground anchors are rated at about 3k-4k lbs. each. This is uplift. You need to run your design through a loading program and get those calcs to the org. If it flies, they will normally accept it. They don't have structural engineers on staff, and as of last year, they did not require a SE stamp on plans. But you should engage an SE just so you can sleep. The wind really kicks up, and it can become a fucking nightmare in far less time than it takes you to understand it has become a nightmare. Belt and suspenders. No injuries or death.

Regarding the setup crew: get a crew chief in place now, make her/him responsible for the care and feeding. Lots of ice cold water, coconut water, zip-fizz. Think: Those kids who retrieve tennis balls at the US Open. Dash in, hydrate, dash out. Honestly. You will run your crew raggedy no mater what you do, so do as much as possible.
-Fox

[chiefdanfox]

I reviewed all of the posts here, and i think you need to consider positive connection between each level, and without a doubt you will need tie downs and guy wires. Remember, you don't get to pour a foundation. You are building a temporary structure that cannot be anchored into the playa with anything other than the ground anchors the org provides. Period. You need to understand how each layer overlaps, and build in a positive connection that goes from the the top of your structure to the ground anchor.

Look into 3/8 structural. Short-leaf pine, USA-Canada. Trojan Horse and Anubis. Structurally skinned with 3/8. If you do a scheduled nail pattern (UBC) you can achieve wind loading integrity.

[Snow]

don't forget to be prepared for wind during construction too. we had some damn crazy winds building this year! we lost many sheets of ply and they caused much damage, and these were all nailed down as is typical. That was one hell of a night and luckly it was pretty much only us and the man/temple crews out there then. I was scared, and that takes a LOT.

DAN!!!

[Snow]

50 ft high and fairly slender. It was a reasonably rigid member...

tehehe

[Peacekeeper]

But you should engage an SE just so you can sleep. The wind really kicks up, and it can become a fucking nightmare in far less time than it takes you to understand it has become a nightmare. Belt and suspenders. No injuries or death.

Amen Brother, sing it!