Overwhelmed by plywood

[Batgirl1047]

Hello smart builders,
The hardest part about my oven build so far is the overwhelming number of choices in material. I am currently stuck on... plywood for the frame? Obviously I am very new to construction projects. Why are there so many different kinds of plywood?! Can one of you smart folks just tell me what kind of plywood I should use for the bottom tray? Does it matter? Should I just get the cheapest one? Do I need to worry about warping?
Thanks in advance,
Taylor

[UtahBeehiver]

I suggest you buy the FB eplans (3 bucks) and study them. It is a good base line for designing and building an oven.

[JRPizza]

Taylor if you have an idea what size of an oven you want to build and how you want it to look in terms of chimney and shape (igloo vs enclosure), in addition to looking at the FB plans as Russell suggests you should find a couple of builds that look like what you want to end up with and bookmark/study them. You will get many of your questions answered this way.
For a quick answer to your question - most builds only have plywood used for temporary forms and supports, which makes quality less important (with possible exceptions). You mention "bottom tray" which I'm guessing is the support for pouring the hearth, is that what you meant?

[Batgirl1047]

Thanks for answering. I do have the FB plans and I've read them a few times. I'm building the 36". The issue i'm facing is brand of material, which they don't really cover. Like I said.... I'm very green.
Bottom tray is what they call it in the plans, but yes, the support for pouring the hearth. Thanks for the tips. I'm definitely gonna go bookmark some builds.
Seriously thanks for the help. So as long as I get the right dimensions the material will most likely hold up?
Thanks again!

[UtahBeehiver]

Some of the best documented builds are located in a stickie called "treasures hiding in archives" or something like that in the Newbie Section. You can use cheap plywood, at least 1/2" (which you remove once the pour is done) or you can use 1/2" concrete backer board which you leave in place after the pour. Either one, you must build a solid temp support system under the material during the pour.

[Chach]

Yes I agree with both UtahBeehiver and JRPizza the plans are important and more as a guide nothing is set in design but it gives you a good base to start on. Brands of product don't really matter as long as the product itself is used for it's intended purpose but you do need the correct type of material to achieve a successful build. What location are you building the oven? This usually will help everyone help you as different areas have different climates and place to purchase ceramic blanket and fiber board (insulation products). Don't be afraid to ask questions this forum is a great resource.

Ricky