> -----Original Message----- > From: R C [mailto:[email protected]] > Sent: June-19-20 12:45 PM > To: Chris Albertson; linuxcnc-users-list > Subject: Re: [Emc-users] Universal spindle speed control for $7 > > > On 6/19/20 1:34 PM, Chris Albertson wrote: > > A 4:1 reduction is possible with gears. The sensor would be mounted the > > same way but displaced off axis 24 mm then fitted with a 80T gear and > > driven by a 20T gear that is itself driven by the drawbar. I would buy l > > gears (mod. 0.5 or Pi/2 mm pitch) as printed gears are not great in that > > tiny size. > > > > I think gears are good because they can be small mod 0.5 or even smaller. > > Two minutes of hunting found this > > https://www.mcmaster.com/2662N31 > > for $3 each. This could be the "large" gear fixed to the sensor. > > > > There is "all the space in the world" above the spindle on the mini mill > > but you need to preserve a way to get a wrench on the drawbar. > > > > The harder part is getting the encoder data into LinuxCNC/HAL. It is > > easy if you have some Mesa cards. More work if the data must go in via > > USB. > > I am still messing with reading quadrature encoder(s) on an RPI, it can > be done.� I am doing that for a few reasons, one > > is for adding something like that to a benchtop mill and lathe, the > other is to track the axes of a telescope mount that I am building. >
A Pi isn't the most suitable unit for that sort of thing. The BeagleBone has two hardware QEI devices. Alternatively there are other processors out there that have the hardware interface. John _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
