looking for flexible shaft coupler for 1/2 inch hex

[Bruceb]

Originally Posted by yarden.saa

We had last year 775Pro on VP gearbox 3:1 direct drive a hex shaft with vex hex shaft coupler with no problem of vibrations. You are probably going too fast, I don't think you need 18000 rpm for a shooter.

no probably not all that but we are spinning a 2 inch wheel

[Bruceb]

Originally Posted by cbale2000

If you're using a versa-planetary anyways, why not just use a versaplanetary encoder?

because the encoder made for the RS-775 pro is much smaller and I have heard good things about it.

[Cothron Theiss]

Ok, so I think there are a few things you should look at to try and fix the problems in the design rather than patch over them. You should have some reduction coming off of an RS-775. You already have the VersaPlanetary in there, why not change it to an actual reduction? This will vastly improve the accuracy and consistency of your shot anyways. As for the encoder, if you already have the encoder set up for the RS-775, that's fine. But you can also use the VersaPlanetary integrated encoder. It works very well also.

[cbale2000]

Originally Posted by Bruceb

because the encoder made for the RS-775 pro is much smaller and I have heard good things about it.

What motor and encoder specifically are you trying to use? Perhaps provide links?

To my knowledge there is no such motor as an "RS-775 Pro"; there is an "RS-775" and a "775 Pro" but these are very different things.

[Tom469]

For a rotary encoder, I suggest you turn the end of the Hex shaft down to ~ 1/4" and use a piece of 1/4" fuel hose, ~ 1 1/4" in length and use a couple of flat spring clamps to clamp the ends. Then carefully align it. The fuel hose and flat clamps are standard lawnmower items.

The harder mechanical flex couplers transmit a lot of vibration to the encoder, and can cause pre-mature failure. The company, that I worked for introduced a flex coupler then discontinued their use. And, went back to the fuel hose.

[PAR_WIG1350]

Originally Posted by cbale2000

<snip>To my knowledge there is no such motor as an "RS-775 Pro"; there is an "RS-775" and a "775 Pro" but these are very different things.

The designation RS-775 is borrowed from Mabuchi Motor Co., Ltd. and it indicates a round, carbon brushed DC motor with a 5-pole, size 7 armature (diameter) and a size 7 housing (length). There are at least four legal motors that satisfy that description:

• AndyMark's RS775-5
• AndyMark's RS775-125
• BaneBots' RS-775 18V
• WestCoast Products' 775pro

The first two are almost identical. The latter two are much more powerful than the former, but distinct from each other. Any one of them could be called an RS-775 with roughly the same degree of accuracy. It is prudent to clarify, but I believe that the motor in question is a 775pro.