Can i control "linear speed" through my prt96 to control a retrofitted stone grinder

[snowstorm]

Hi guys
just throwing this out there.

I bought an older prt 96 probably 2004 model, which isnt my main focus right this moment but will be shortly.

My main focus right now is my stone grinder an older german machine, which is pneumatically run using air pressure and hydrolic oil to slide a shaft in and out about 12 inches. At the time this was an excelent method of controlling linear speed through valving the oil feed. The big issue with this method is that temperature affects oil viscosity and hence settings are contanly being affected by temperature and are hard to set accurately.

I need to accurately be able to set "linear speed" at say 350mm/min on the outward pass and say 450mm/min on the inward pass.

I also need to be able ramp up and ramp down the "linear speed" through the pass as well.
for eg. start at 100mm/min build up to 300mm/min mid pass then back down 100mm/min at the end of pass

Now that you have an idea what i need to accomplish.

Here is my question??

1. Can i somehow use my PRT96 to control a Ball screw if i removed my pnematic system to retro fit newer elctronics.

2. Can the PRT96 be able to control Ramped up and down linear speed

I know its a lot to take in but i'd appreciate any feedback at all
big newbie in the cnc department.


Thanks
justin

[Brady Watson]

I'll have to think more about this...but I think it is at least partially doable with some post processor modifications. You can get the 'crescendo effect' of ramping speed by modifying the VR settings, to a certain degree.

I'll think more on this...

-B

[donek]

Is this a snowboard or ski grinder? I plan to retrofit ours this summer with an arduino (http://www.amazon.com/gp/product/B006H06TVG/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) and TB6560 (http://www.amazon.com/gp/product/B008BGLOTQ/ref=oh_aui_search_detailpage?ie=UTF8&psc=1)
Preliminary tests with the arduino and TB6560 indicate programming will be relativley straight forward.
If you are trying to cut chevron patterns, you may have a tough time controlling the speed with the shopbot software. If you want to run linears and cross hatch patterns, it should do the trick.

I'd be very interested to see the linear slide system on your grinder. Our old Grindrite's primary problem is the linear slide that is bathed in water and easily gets grit in the ball bearings. I plan to redesign it to run on round stainless linear bearing rods and most likely UHMW bushings.

[snowstorm]

yes exactly
This is an older ski grinder.
you can pay a pretty penny buying new
I can acomplish a couple different kinds of linear structures for different snow conditions ranging from wet snow to really cold conditions, as well as cross-hatch structures for racing

Arduino-6560, this is new to me. Are you able to ramp up and ramp down linear speeds in a programed manner. What kind of investment are you looking into spending to retrofit these items to your grindrite?

**My linear slide system that holds and supports the diamond dressor is basically composed of 2 cylinders(about 1.5"-2" diameter)
there spaced about 2 inches apart,
one infront of the other
The diamond dressor is sleved through these 2 cylinders and is supported far from the water and dirt that is produced from grinding skis.
In your case is it possible to lower the water level to get the linear slides away from the grite or reposition the slides above water level.

[snowstorm]

Any chance you can elaborate a little on the arduino and tb6560

I'm not to savy in this department it's really another language to me.
what it is?
how you use it?
what program do you use to control things?

i can take a picture of my sliders if you like

[donek]

An arduino is a microcontroller that can be used to control many things. It's commonly used in small robotics projects, home automation, basically anything you might control. As the links show, they are very inexpensive. The TB6560 is cheap stepper motor controller that can be controlled easily with an arduino or a computer. The two units run less than $50 together, but would require some additional components to develop a complete functioning system.
You could start here:
http://www.arduino.cc/
Arduino is programmed in a version of C. There is a ton of information on that site. If you're not familiar with them, you may not wish to embark on such a journey unless you have additional automation projects to implement. It is relatively simple to write code that would control a ramped motion with a stepper motor if you are mathematically inclined. There are many training/educational videos on the use of arduino. I started with Jeremy Blums:
http://youtu.be/fCxzA9_kg6s?list=PL54C74D0DC52BC0D1
By video 4, I started simply searching for the bits and pieces I wanted and developed a control system for our dye sub station. I'm also creating a temp control system for our presses that performs several other functions. I have several different projects I'm working on with them.

[Brady Watson]

Check out the MI command in SB3.

You might want to consider managing the oil temperature first (either heat or cool) to get that machine where it needs to be...an Arduino can be used for this as well.


-B