Four FIRST Choice items that could actually harm your season

FIRST Choice is a virtual extension of the Kit of Parts: a pool of donated robot components, tools, and other interesting stuff.  These items are available for teams to claim for only the cost of shipping from Indiana.

In this article, we explore four FIRST Choice items that could actually make your 2019 season worse if you order and use them.


1. Norgen Pressure Relief Valve

It's simple: teams should not be using this relief valve.  Since this is an adjustable device, and since it's not pre-set to the correct relief pressure (125 psi) at the factory, teams must adjust the relief AND prove to Robot Inspectors that it has been set correctly at each event.  At best, this adds a slight delay to every inspection process.  At worst, the design of your robot's entire pneumatic system may be called into question as you reach inside your robot with wrenches to change the relief setpoint.

Instead, teams should use Control Devices' ST-series soft seat safety valve, which is sold as McMaster-Carr part number 48435K714.  This nonadjustable $5 ASME relief valve was made explicitly legal in the 2018 FRC game manual.

2. Diligent DMC 60 Motor Controller

This discontinued product from Diligent Inc., a National Instruments company, is a blatant and unapologetic ripoff of the (also discontinued) Victor SP.  Introduced for the 2015 FRC season, the Victor SP was the result of an epic and unprecedented collaboration between VexPro and CTR Electronics, two great organizations which have done more than their share to improve the quality and competitiveness of FRC robots.  On the other hand, Diligent's product was just intended to undercut sales of a successful existing product without offering our community any new features or better performance.  Instead, this motor controller is more poorly supported, is used by far fewer teams, and is physically larger and heavier than the Victor SP.

If you're still looking for a PWM motor controller in FRC, get yourself a SPARK.

3. Denso Throttle Motor

A few teams have found a use for them, but they are still mostly only useful for memes.  Why an average team would ever willingly use this motor on a robot is one of the universe's greatest unanswered questions.  Attempting to answer this question will be a poor use of your time this season.

4. Norgen Pressure Regulator and Pressure Gauge

Not only are these components larger and heavier than the alternatives, they'll require you to use additional brass fittings to mate with standard 1/4" OD tubing.  Using these products require you to seal an 1/8" NPT fitting with either Teflon tape (small pieces can tear away and get stuck in bad places) or a liquid thread sealant (must account for curing time and temperature).

Teams should instead purchase Nitra push-to-connect regulators and gauges using their $35 Automation Direct voucher.

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