Thread: VEX Tetras
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Unread 22-10-2006, 11:46
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AKA: Arthur Dutra
FRC #0228 (GUS)
Team Role: Electrical
 
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Re: VEX Tetras

The 1/3 scale tetras Art04 and I constructed, and have been used heavily for two years now, were made out of 1/2" CPVC water pipe available at Home Depot. Use CPVC (it's yellowish in color not white), NOT PVC, it has a smaller OD.

1 Cut the CPVC to 10" lengths to get good 1/3 scale tetras.
2 To connect the CPVC into tetras cut 1" long pieces of 3/8" wood dowel.
3 Apply gorilla glue and drive plugs into the pipe ends until flush.
4 Let dry.
5 Photo reduce the drawing of a FRC clover to 33%, or draw your own in CAD.
6 Cut clovers out of a scrap piece of vinyl siding with heavy duty scissors
or sheet metal sheers.
7 Pre-drill plugged pipe and clovers for #6 screws.
8 Assemble tetras with #6 x 1" sheet metal screws.

These tetras cost about $1.50 each to make.

We made regular tetras, vision tetras (with 1/8" Lexan painted green), and hanging tetras (with magnets from home depot). Each tetra weighs about 1 pound. A good scale match to FRC tetras. We found that vinyl siding (also a PVC) was the most durable for clovers. It would still occasionally break, but would last through several ROUGH demos before failing.

The goals were made in a similar fashion using 1/2" EMT (electrical metallic tubing) also available at Home Depot.

1 Cut the EMT to 24" lengths to get good 1/3 scale side/end goals, or 16"
and 13.25" for a center goal.
2 To connect the EMT into goals, cut 2" long pieces of 5/8" wood dowel.
3 Apply gorilla glue and drive plugs into the pipe ends until flush.
4 Let dry.
5 Photo reduce the drawing of a FRC clover to 33%, or draw your own in CAD.
6 Cut goal clovers out of a piece of 1/8" thick Lexan with a band saw and
bend it with a heatgun.
7 Pre-drill plugged pipe and clovers for #6 screws.
8 Assemble goals with #6 x 2" sheet metal screws.

Goals cost around $6-8 each to make.

Everything was purchased at Home Depot. Except we didn't buy a length of vinyl siding, we had some left over from building our house. A one foot long piece of siding should make many dozens of clovers.

Here's some of the finished products at the National Science Teachers Association conference being played with by a Vex 228 Gus and FRC 173 Rage!



Best mini tetras we've seen yet!
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2009 CT Regional Motorola Quality Award
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2012 WPI Regional Finalists
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