kenh
What is the best foam for building now that Depron is going away? I have tried model airplane foam but it is way to flimsy. What is the closest to Depron? Thanks
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Wildthing
I still get my Depron from RC Foam, does have a slight curvature to it so you plan carefully the layout of the pieces so everything is equal and easy to straighten. Some are starting to use the foam from HK .
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TomMonton
I moved over to MPF grade-A entirely for everything anymore. I still have a box of crooked depron and only use that for the odd little things that aren't near as critical.

I've had very good result with grade-A mpf.
I did not care for grade-B mpf.
I have used XPS but requires more support.
Foam board and remove the paper for light weight skin work.
Fly like your mad at it.
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Nightswatch
I personally think foam board is easy to find great to work with rather then spend money on shipping, for MPF Its a Gimmic you see MPF at hobby shops and the price tag on it is rather funny

But DT foam . the paper is easy to peel off foam is easy to form bend or do what ever with and the best part is once you do some research you can find bigger sizes of foam board for instance my Su 34 build wings and fuselage is one piece one 4 x 8 sheet or main set up instead of only 2 foot wide MPF foam which is really good for nothing other then skinning or making small planes

As for strength foam is foam double it up do what ever in stress point areas but for what its worth dollar tree foam is cheap and i would think the go to foam least in my experience with working with foam
Although i use Balsa 99 percent of the times for wings etc and only foam for fuse area with wood reinforcement as well as silk span or fiber glass she is one strong light weight plane

IMG7519.jpg 
If you think you got your flying under control, Your not going fast enough
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SukhoiLover
This is not a timely reply, but here goes . . . .

In class we use Adams Foam Board--it's cheap and available from Dollar Tree. It can be a challenge to fit plans/parts onto a 20" x 30" sheet, but sheets/parts can be splice together. Recently we found some Ross Foam Board at Walmart for . . . $0.88 a sheet! While they all should be the same, we found slight differences.

The Adams white is the benchmark. I still love building with the stuff--probably because I've done it so much I'm comfortable with it. The paper adds a good bit of strength, but (according to Flite Test) makes up roughly 40% of the foam board weight> The paper can be removed fairly easily.

The Adams black paper seems to peel off very easily, much easier that the Adams white board. In fact, it can be difficult to keep it in place (especially as score folds or control hinges).

The Ross Foam Board paper seems to be very slightly thinner (could be my imagination?), and is a chore to remove compared to either Adams Foam Boards. Ross Boards may (?) be ever so slightly stiffer than the Adams Foam Board.

I also have some left over green Lowe's fan-fold. I don't care for the perforated finish, and peeling the plasticy covering off is the most difficult of all--unless you know the secret. The uncovered foam is stiffer and more brittle than either uncovered Adams or Ross, but it sands like a dream. (Oh, the secret? Tape over the foam with cheap packing tape and peel off the tape. The underlying plastic coating lifts off without complaint.)

So here are the ways I use each type of foam:

*  Adams White for general-purpose building.

*  Adams Black if I want bare foam.

*  Ross for general building, or for structural members.

*  Lowe's for KF airfoils (plastic coating removed).

Completely non-scientific--your mileage may vary--don't wear white after Labor Day--you have been warned--etc.

Fly safely--more than 6' from others--and keep building. It helps one's sanity, doncha know?
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