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AWillette
01-04-2011, 11:48 AM
I posted this over in the developer section of the forum, but realized that since there are a lot of DIY indexers being made that I could probably get a quicker response over here:


So over my winter vacation (one of the the perks of academia) I started sketching out an idea for custom tool that would require use of the A/B-axis, ideally with a small 12v stepper. Basically I saw some work people have done with a 6-axis arm and knew I could do similar with only a 4-axis machine (because thats what I have access to). I figured it would be something fun to work on so decided to hit the ground running when we started up after the break.

I have a couple questions that I thought I'd post here for some advice. I did go through the indexer installation documents that came with the machine as I figure that would be the best place to look, but they're for an earlier version of the control box and I wasn't able to gleam too much from it.

1. I have a PRSstandard with the latest control box and opened up the cabinet first thing when I got into the shop today. I see there are 4 stepper controllers - are the two X-axis's controlled separately or is the 4th controller available for the A-axis? I'd like to avoid having to buy a new controller as I don't own the machine and don't have too much money to be throwing into this project.

Answered this with some digging through the archive. Since I'll have to buy a stepper controller this project will be need to be put off for a bit. I wonder if ShopBot sponsors projects...

2. What are the properties of the stepper pulses (voltage, etc.). I'm hoping that I would be able to step-down the voltage in-line without degrading the pulses, but would need to know what I'm dealing with before I start developing the circuit for this.

So any help would be appreciated. I've done enough reading that I'm pretty sure that all the hardware pieces are in place, its just a matter of putting them all together properly. I'll be able to develop the G-code for the task via some basic scripting in Rhino so I'm not worried about that part of the project either.

Thanks in advance!

myxpykalix
01-04-2011, 02:44 PM
If you have an indexer, you have a controller. You have 2 for X, 1 for Y, 1 for Z. If you are thinking you could just go buy a stepper motor and go then you are mistaken. You need both a stepper and a controller. Someone else may have more specific model numbers for you but others have set up indexers for 2 to 5 hundred. Go back in the indexer section and you should find specific models and numbers for a setup. Lokk for a post titled something like "setup an indexer for $200.00" or something like this.

AWillette
01-04-2011, 08:01 PM
Yeah, I got turned around and read the PRT indexer instructions I have to mean that the alpha needs a new controller but the standard doesn't. I should be able to do the project without the 4th axis but without a good chunk of the 'wow' factor I was hoping for. Despite how tempting it is I'm not (yet) going to dump the money for the controller and stepper into a machine that I don't own.