set screw identification

[jberend]

Hi - does anyone know the size of the set screw for a Tetrix axle wheel collar 739092? I was also wondering what Andymark motor would work well with a Tetrix motor mount and would spin faster for shooting balls.

thanks

[Peyton Yeung]

The AndyMark NeveRest 3.7:1 has been shown to work for a side by side wheeled shooter.

[GeeTwo]

Based on some measurements of the photo, it looks like a 10-32 with a 3/32" allen drive.

[pilleya]

I was also wondering what Andymark motor would work well with a Tetrix motor mount and would spin faster for shooting balls.

If you are limited to purchasing only from Andymark the NeveRest 3.7:1 is your only real simple option and will work well with the Tetrix motor mount:

http://www.andymark.com/NeveRest-3-7-12V-Gearmotor-p/am-3461.htm


The lowest reduction gearbox in the Helical gearbox series( 20,40,60) is the 20:1 which has a free-speed of around 300rpm. This is approximately twice as fast as the Tetrix DC motor, but unless you have a wheel with a very large diameter( or a two wheeled shooter) this will still be far too slow.

You could use something like a 20:1 and have another set of gears that increase the speed( something like a 1:3 or 1:4), but it ends up a little complicated.

Because the NeveRest motor is a 550 class motor there are quite a few different gearboxes available to use if you are ok with ordering from another supplier.

- The VersaPlanetary Gearbox which will allow you to adjust your flywheel speed easily: http://www.vexrobotics.com/vexpro/motion/gearboxes/versaplanetary.html

-The 4:1 Planetary Gearbox for RS550 available directly from Banebots( Andymark is out of stock of this particular gearbox):
http://www.banebots.com/product/P60S-4-5.html

However neither of those two gearbox are compatible with the Tetrix motor mount, the VersaPlanetary has a few different mounting plates available which shouldn't be too difficult to integrate with the rest of the Tetrix construction system.

[FrankJ]

From the FTC forum (http://ftcforum.usfirst.org/showthread.php?5734-Tetrix-axle-set-collar-set-screws) (2015 thread):

I just received an email from Pitsco that [one of] their vendor(s) mistakenly shipped collars with metric set screws that would require a 2 mm Allen wrench / "hex key", which is 5.04/64th's of an inch.
Per http://www.tetrixrobotics.com/gettin...ools_guide.pdf, the correctly-manufactured collars require the 1/16" (or 4/64") hex key.
Since the hex socket is 0.016" bigger than the 1/16" hex key, this explains why we are rounding the sockets.

It had also confused me why I had found that they were 4 mm set screws, but another Mentor found that a #6 screw fit perfectly - just luck of the draw.

We will segregate (discard) the metric collars. Pitsco has said they would replace the ones with the wrong set screws.

Most hardware stores have thread gages if you have a loose set scew to test.