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http://www.vhipe.com/product-private/SuperPID.htm
Thought this might be of interest to guys using router motors on CNC.
Nelson

I saw one in person and it was pretty darn cool. He had it wired in to Mach 3. Only thing that might be a little odd was that his computer crashed and it went to full speed. ick!

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Well I just installed one on my CNC Router. Man this is very nice. Now cutting the acrylics that I do is so much better. No melting with small endmills. Less problem trying to find that feed and speed that is almost right.

As far as testing it to make it run away (crash the PC or anything else?) I have not been able to do so. I would suspect that the guy Andy referred to did not have it set up correctly. The instructions are vague on MACH3 setup and config. But with a little reading on some forums and tweaking this thing is great.

Just wanted to pass along this for anyone that is contemplating it. I'll be more than happy to help with your config as well.

Mike

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I'm outside looking in, just farther from the window than most.

Mike, are you running Mach3?
I also find that being able to control feed and speed "on the fly" is a benefit.
Nelson

Yes I am running mach3. I also milled some aluminum today. WOW, that was nice. before I have had to go to my friends machine shop. Now I can at least do some basic milling without need of his shop.

Mike

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I'm outside looking in, just farther from the window than most.

Mike, are you saying that you have some low end torque now that you didn't have before?

That's a BIG You Betcha.

MK

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I'm outside looking in, just farther from the window than most.

This is something I've been wondering about. I'm getting a VFD powered spindle for my machine that apparently good down to about 4500rpm min. I guess you can go slower but you lose power and cooling ability. As far as I know, VFD controlled spindles are not speed controlled right? i.e. if you set it for 5krpm no load, it will drop in speed when you add a load yes?

If this is true, a router with superPID would I think, out perform a standard VFD/Spindle set up as it would increase power to maintain the set speed where the spindle would just bog down, at least at low speed.

I know that there's a feedback loop in Mach3 for spindle speed but I haven't looked into it much. I wonder if it's possible to add an optical sensor to a Spindle and get similar control. Anyone know?

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

What are you using for a router?

I just use the speed control that is built into my router. Is there an advantage to using this setup verse the built in speed control?

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Brad
Avon, OH

Brad, in order to use the SuperPID you must first bypass the speed control on your router. The advantage of the SP is it can be controlled by Mach3 or EMC2. Not only on and off but speed settings using Gcode commands. These are usually definable in your Tool database as well. You still have the advantage of using the override in MAch3 as well. If you decide to wire it with a Spdt switch you can use the manual control pot as well as Mach3.

So far I am very pleased with this setup. One thing though. If you plan on running a long time at the lower RPMs below 10K, it is recommended to add an A/C fan to the top of the router to help cool them, as the fans that are built in are designed for higher RPMs. I plan to add a 32mm highspeed A/C fan to my PC 690, this must be wired separately so that it is not controlled by the SP so as not to slow it down as well.

One other note, the LCD is mounted to the board and I don't like that setup. I have found using a single row 16pin header and an IDE cable between them, I can then have the LCD remotely mounted. This allows more flexibility to mounting the SP with your other electronics for better cooling from your enclosures fans.

Mike

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I'm outside looking in, just farther from the window than most.

I'm going to have teknomotor 1hp spindle but don't have it in yet. I'd send a link but their website seems to be down



Yes - the SuperPID will maintain a set RPM irrespective of load. i.e. if spindle speed goes down, it will up the juice to hold RPM until it runs out of juice. This is especially useful at low RPM where it takes very little current to maintain a given no-load RPM. Move it into material and the spindle speed goes down. With the SuperPID, it stays constant.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I'm no expert on this, but since VFD powered spindles are controlled by the frequency of the 3 phase current going to them, they should maintain a constant RPM under load even though they are usually "open loop" devices with no feedback like the Super PID router speed has. VFD spindles are a lot like stepper motors--they might drop some "steps" along the way, but the speed doesn't change much until it stalls. Routers are always running at 60 (or 50) Hertz, so there is no set "timing" that is determining RPM. It's a function of voltage/current exclusively.

On my Colombo spindle, unless I run it too slow, it doesn't change RPM under load. Too slow and it doesn't slow down--it stalls. The power curve on my spindle (and I think most spindles for that matter) really drops off quickly as the RPM/pulses per second drop. I was skeptical about the value of VFD spindles over routers until I got one. It's so much quieter, and has a lot more power than a router of the same rated HP.

Dave

That's excellent news!

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Now that I think back, I do remember that from squirrel cage motors from school. In the lab, they had these big old motors (like 400lbs - 12"+ in diameter, 460v) and I vaguely remember that we'd load them up until they "slipped" as it's called for those types of motors. It would get louder and louder until the slip point.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Just an update for everyone on the use of the Super PID2.

I have been using it almost daily for months now. Many times for long periods at low RPM's. I mill a lot of plastics that require low RPM's as well as aluminum. I have yet to have a problem over heating the router even at 5000 RPM for hours on end, without adding an external fan. When milling wood I have found that lowering the rpm to around 16000-18000 results in much quieter working conditions with no loss in cutting results.

All in all, this has been a great option for the dollar and I would highly recommend it if you are on a budget.


Mike

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I'm outside looking in, just farther from the window than most.