Plywood - talk to us about how you use plywood

[DonRotolo]

I can only competently answer a few of these:

S2S (Sanded two sides) is the term for very smooth on both sides.

Aircraft Plywood is one term for high-ply material, 'hardwood plywood' is the term for what used to be available only in Birch (but now in oak, maple and cherry for example).

Both are available at my local Lowe's, and the really thin aircraft stuff is available at Michael's and A C Moore (craft store chains here in NJ).

Lasers leave a charred edge, most saws don't. Straight cuts are superior on a table saw, curves and complex shapes are trivial for a laser. But thick material (3/4") isn't easy on some lasers.

[Ian Curtis]

We have not used that much of it in the past, but our pit neighbors in Seattle did. 1899 had a gorgeous plywood robot, and we plan on borrowing some of their construction techniques this season.

I've attached a few pictures I took at Seattle this year. For robot building they had cycled through a bunch of different kinds, but ultimately settled on this 5mm sanded ply, which is actually slightly thinner than 5mm. It is super cheap (under $15 for a 4x8 sheet). They sealed it as sheets, and then just put it in the laser cutter and got out puzzle pieces. In cutting the joints they didn't consider the kerf of the laser and the joints were definitely plenty tight.

Because the wood is so cheap, they built multiple iterations of their frame. I forget the exact number but it was at least five. Due to the puzzle-piece nature they also had some fun figuring out the best order to put it together. To hold it together they buy wood glue in 5 gallon buckets, and spent a sizable amount of money on Harbor Freight clamps. Anyone who went to their pit can attest that they had a lot of clamps.

If someone from 1899 is around feel free to correct me or send me a PM, because I've actually got a few more questions.

[fb39ca4]

Originally Posted by Ian Curtis

We have not used that much of it in the past, but our pit neighbors in Seattle did. 1899 had a gorgeous plywood robot, and we plan on borrowing some of their construction techniques this season.

I've attached a few pictures I took at Seattle this year. For robot building they had cycled through a bunch of different kinds, but ultimately settled on this 5mm sanded ply, which is actually slightly thinner than 5mm. It is super cheap (under $15 for a 4x8 sheet). They sealed it as sheets, and then just put it in the laser cutter and got out puzzle pieces. In cutting the joints they didn't consider the kerf of the laser and the joints were definitely plenty tight.

Because the wood is so cheap, they built multiple iterations of their frame. I forget the exact number but it was at least five. Due to the puzzle-piece nature they also had some fun figuring out the best order to put it together. To hold it together they buy wood glue in 5 gallon buckets, and spent a sizable amount of money on Harbor Freight clamps. Anyone who went to their pit can attest that they had a lot of clamps.

If someone from 1899 is around feel free to correct me or send me a PM, because I've actually got a few more questions.

1899 member here. You got most of that correct, except the plywood we used was slightly over 5mm-5.2 to be exact. We originally used wood that was 5.1mm thick, but it had issues with voids and the filler used in them not being cut all the way through, while the final wood we ended up using did not have that problem. However, our CAD model still had slots for 5.1mm wood in many areas, and we never got around to changing them after switching to the 5.2mm wood, which is why the joints were tight. Also, I believe we built eight chassis, including the competition one, and a backup chassis we bagged with the robot in case the main one was irreparably damaged.

[s_forbes]

One of the best robots I got to help design was made of plywood. Our chassis design used various thicknesses of baltic birch plywood (1/2, 3/4) depending on the load seen by each frame member. Some lower quality 1/4" plywood was used to brace the frame members. All were held together with good wood glue and long staples. We were fortunate enough to have a shop with good saws to get all the pieces cut precisely, and a pneumatic staple gun. 2009 was a year with low loads on the drivetrain, so this was a great material.

http://www.chiefdelphi.com/media/photos/32671

To my knowledge this is the only robot built with 2x4s and plumbing supplies to win a quality award. Krylon paint works wonders!

[fb39ca4]

Originally Posted by s_forbes

To my knowledge this is the only robot built with 2x4s and plumbing supplies to win a quality award. Krylon paint works wonders!

Speaking of plumbing supplies, there was a team at Championships this year that had a PVC pipe chassis. Anyone remember which team that was?

[donkehote]

We used layered plywood to make prototypes, such as our shooter this year.
Other than that, we dont really use much plywood.

A bandsaw is great for making curved cuts when you don't have a laser. smaller cuts may require thinner, wood specific blades, but other than that, bandsaw, table saw, and jigsaw are all the tools you need to make just about anything out of plywood.

My favorite for assembled/disassembled are dowels and screws. I made a locker organizer that was assembled in situ, and disassembled when you had to swap lockers. Just used dowels with some #8 screws to hold it all together. I could easily stand on the shelves in place (3/4 marine ply ftw) and it all came apart in about 5 minutes.

[Jay H 237]

We've never used much plywood, In the past we used 1/4" to fasten and support the electronic components since it made it easy to mount them but now we have been using a lighter corrugated plastic the past few years.