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wallyblackburn
25-10-2017, 04:03 PM
So, just came across this today:

http://www.centroidcnc.com/centroid_diy/acorn_cnc_controller.html

And, honestly, trying to figure out why everyone isn't freaking out about it? Seems like the answer to a lot of prayers in the DIY CNC world. What am I missing?

Regards,
Wallace

Web Goblin
25-10-2017, 09:43 PM
Ive been looking at this myself as I'm building a new machine and I really don't want to use mach 3 or 4. I should have stuck it out with eding cnc but this does look interesting.

Nr1madman
25-10-2017, 10:00 PM
I am just a happy hobbyist so take my opinion with a huge pinch of salt.

This did not look attractive to me because of gcode limitations and only 3 axis in cheapest software option.
Also the GUI does not look intuitive for me..
Im not using mach for my future machine, went for uccnc instead. :)


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m_c
26-10-2017, 02:02 AM
The two things that standout to me, are you need to add the cost of the software to do anything more than basic machining, and outputs/inputs are limited, with no obvious way to expand.

Ger21
26-10-2017, 03:25 AM
Seems like the answer to a lot of prayers in the DIY CNC world.

You're praying for less features for more money?

Zoprano
26-10-2017, 11:56 PM
http://weihong.adcomma.cn/en/chanpinzhongxin/yundongkongzhika/20160422/15.html




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wallyblackburn
27-10-2017, 02:50 PM
You're praying for less features for more money?

That's fair - I may have overstated a bit. Also, I was thinking that this was a standalone controller similar to the DDCSV1.1, but now I see that it only works in conjunction with their software.

Still intriguing though. I really do not like depending on Windows PC for realtime functionality.

Regards,
Wallace

Ger21
27-10-2017, 03:09 PM
With the exception if Mach3 running on a parallel port, just about all hobby controls rely on their motion controller for the "real time" stuff. Windows is not an issue at all. I've been using machines costing well over $100,000 with Windows based controls for nearly 20 years, and I've never seen Windows cause an issue.
I would not want a machine control that didn't run on a PC, as you lose all of the advantages that having a PC at the machine brings.

Web Goblin
27-10-2017, 08:41 PM
Most of our new machines at work now run on windows based controls and I must admit that it does give a lot of options that were missing before. But on the other hand we still have a couple of old machines that run on plc's and they don't give us any problems at all with the control side of things. If something has gone wrong most of the time it has been a hardware issue.

Bravin Neff
27-10-2017, 10:29 PM
You're praying for less features for more money?

Just out of curiosity, why do you say this? I am currently designing my first DIY CNC machine, and from the homework I have been doing, this seems like the ideal CNC control for those looking for the closest thing to a commercial CNC control.

Ger21
28-10-2017, 01:24 AM
There is no perfect control for everyone. If there was, then there wouldn't be so many different ones available.

I just don't see the Acorn as the holy grail of cnc as so many other do.
There are other controls that offer more, for less money.
The Acorn has some advantages in some areas, and others have advantages in other areas.

If the Acorn is what you're looking for, than by all means go out and buy it.
I decided to go with UCCNC, which is a better fit for me.

My UCCNC setup (UC300ETH + UB1 breakout board) is roughly the same price as the Acorn with the $99 pro level software.
The Acorn gives you 4 motors, UCCNC gives you 6.
The Acorn has 8 outputs, the UB1 has 14.
The Acorn has 8 inputs, the UB1 has 23 + 2 analog inputs.

The Acorn does have software advantages.
UCCNC does not have rotary axis support at this time. It will eventually, but it might be a year or two.
UCCNC does not have screw mapping.
UCCNC does not have cutter comp, but it will soon, as it's been under development for a few months now.
I believe that the Acorn is much better at digitizing, but it's limited unless you buy the $499 software upgrade.

It all comes down to what you need from your control.

Bravin Neff
28-10-2017, 01:56 AM
There is no perfect control for everyone. If there was, then there wouldn't be so many different ones available.

I just don't see the Acorn as the holy grail of cnc as so many other do.
There are other controls that offer more, for less money.
The Acorn has some advantages in some areas, and others have advantages in other areas.

If the Acorn is what you're looking for, than by all means go out and buy it.
I decided to go with UCCNC, which is a better fit for me.

My UCCNC setup (UC300ETH + UB1 breakout board) is roughly the same price as the Acorn with the $99 pro level software.
The Acorn gives you 4 motors, UCCNC gives you 6.
The Acorn has 8 outputs, the UB1 has 14.
The Acorn has 8 inputs, the UB1 has 23 + 2 analog inputs.

The Acorn does have software advantages.
UCCNC does not have rotary axis support at this time. It will eventually, but it might be a year or two.
UCCNC does not have screw mapping.
UCCNC does not have cutter comp, but it will soon, as it's been under development for a few months now.
I believe that the Acorn is much better at digitizing, but it's limited unless you buy the $499 software upgrade.

It all comes down to what you need from your control.

Interesting. I'm new to DIY CNC, and I'm curious to know what one would do with all those inputs and outputs on the UC300eth? Are those actually similar to the 8 outputs on the Acorn? After reading the documentation on the Acorn, they call them "PLC outputs" which seems identical to what commercial CNC has always called spare M-codes, whereby you can control external things via M-code, and the acorn ones are even programmable as latching or non-latching, under full ladder control. This is exactly what commercial CNC controls have had forever - are you saying UCCNC has this too?

I have downloaded the UCCNC software and played with it, fell in love with it and swore this was the direction I was going to go until I realized it didn't have cutter comp, fanuc macro B and some other things. Those were deal killers for me. I've grown up my entire professional life around Fanuc, Mori Seiki and Okuma, and the Centroid hardware+software was the first control system I came across where I said "ah, here it is." Then after some homework, it made sense in that they've been a commercial CNC house for a long time just now crossing over to the DIY world, whereas these other solutions I've been looking at started out in the DIY world, pushing more and more to match the commercial feature set.

By the way, I've enjoyed seeing your website for a while now.

Ger21
28-10-2017, 03:32 AM
I'm new to DIY CNC, and I'm curious to know what one would do with all those inputs and outputs on the UC300eth?

Whatever you want. Inputs can be used with sensors, switches, pushbuttons, signals from servo drives, encoders, probes, MPG's,....
Outputs can activate relays, contactors, solenoids, LED's, .....

You can create your own M-Codes in UCCNC, which are written in C#. It doesn't have ladder, but you can write what they call macroloops, which are macros that run continuously in the background.

If you need full Fanuc macro B, I think your only option is Mach4 Industrial. But you can do more basic parametric programming in UCCNC and most others.
I have no use for parametric programming, doing everything I need in CAM.


You're not going to get a $10,000 control for $300. No hobby controls are perfect. UCCNC is relatively new to the market, and I expect it will be maturing for a few years still. But for me, it's headed in the direction that works best for me.

Bravin Neff
28-10-2017, 03:50 AM
Whatever you want. Inputs can be used with sensors, switches, pushbuttons, signals from servo drives, encoders, probes, MPG's,....
Outputs can activate relays, contactors, solenoids, LED's, .....

You can create your own M-Codes in UCCNC, which are written in C#. It doesn't have ladder, but you can write what they call macroloops, which are macros that run continuously in the background.

If you need full Fanuc macro B, I think your only option is Mach4 Industrial. But you can do more basic parametric programming in UCCNC and most others.
I have no use for parametric programming, doing everything I need in CAM.


You're not going to get a $10,000 control for $300. No hobby controls are perfect. UCCNC is relatively new to the market, and I expect it will be maturing for a few years still. But for me, it's headed in the direction that works best for me.

I could have swore I just read on the Centroid site that the CNC12 software with the acorn (and the higher DIY boards) have macro b. Their retrofit controls do. Funny you say you're not going to get a $10K control for $300. Today's $300 control easily outspec the way more expensive controls from the 90s, in most respects. I just read on the Centroid spec sheet that it does 2,000 block look ahead. In the late 1990s I used to work on Mori Seikis where a "data server with RISC processor" was a $10,000 *option* and that gave you... wait for it... 480 block look ahead! And we thought that was that cat's meow, LOL.

What's frustrating is seeing something like UCCNC - which I'm very attracted to - has all these features, clearly way ahead in many respects of what we had in the 1990s, yet it doesn't do cutter comp, which we had in the 80's'. I haven't paid attention to the DIY CNC world until fairly recently, but what I have been studying suggests it really took off with mach2/3 about 10-15 years ago. Its very impressive in many ways, but with these frequent and frustrating blind spots.

Ger21
28-10-2017, 01:46 PM
99% of DIY CNC users don't use Cutter Comp, because they have their CAM software do it. That's why UCCNC didn't have it.
But, as I said, it's being developed, and should be available soon. (I've seen some screenshots of a comped toolpath).

I didn't say you can't have the features of a 25 year old control for $300, I meant a current $10K control.
Yes, hobby controls can do a great many things that high end commercial controls can do, for a fraction of the price.

As for the Lookagead. There's a lot more to it than just how many lines it looks ahead. Different controls have different methods to determine how they follow the commanded path, and how much they are allowed to deviate from the path. The trajectory planner can make or break a control.
If I had to guess, I would expect the Centroid planner to perhaps be a bit better than UCCNC's, because it's been around a LOT longer, and it's been known as a higher end control. But I also know that UCCNC's planner is much better than Mach3's.

Bravin Neff
28-10-2017, 02:57 PM
99% of DIY CNC users don't use Cutter Comp, because they have their CAM software do it. That's why UCCNC didn't have it.

It makes sense. Its probably a function of how one uses a machine, what one cuts and one's expectation. If you run into material you haven't cut before, or a geometry that forces you into to a setup that isn't ideal, and the tool deflection creates an outcome out of tolerance, you can either lie about the cutter diameter in cam, re post and rerun it. Or make a quick radius comp and rerun just that section. I think the latter is baked into most machinist's habits. The former has become perfectly reasonable beccause cam has become nearly ubiquitous at all levels, even in the home.


As for the Lookagead. There's a lot more to it than just how many lines it looks ahead. Different controls have different methods to determine how they follow the commanded path, and how much they are allowed to deviate from the path. The trajectory planner can make or break a control. If I had to guess, I would expect the Centroid planner to perhaps be a bit better than UCCNC's, because it's been around a LOT longer, and it's been known as a higher end control. But I also know that UCCNC's planner is much better than Mach3's.

Interesting. I played around with both mach3 and UCCC, and I couldn't get along with mach3 at all. Not sure why, but UCCNC seemed way better thought out. I could make things happen immediately. Speaking of lookahead, for my day job I sell Okuma machines, and its amazing how they do it. The look ahead is infinite... the entire program is calculated. The other part is that the tolerance is adjustable, both by a dialog page or in the g code itself. Giving the cutter path more tolerance makes it more aggressive in corners and cycle times speed way up. Think roughing a mold, where 0.020" is left everywhere. There's no reason to hold tight tolerances, and time is money. Then for finishing passes you tighten up the tolerance and the acc and decs get less aggressive accordingly.

Ger21
28-10-2017, 03:30 PM
On big, expensive machines, the controls are often tailored to the machine. Where a hobby control like UCCNC is a general purpose control, used by many different types of machines. So what you end up with is something that works well on most machines, but could always be a bit better. CNC Drive is planning on working on a new trajectory planner soon, with S Curve acceleration, which will be very nice for machines capable of high speeds.

My day job is running big Italian routers, in the cabinet industry. The controls on these machines are tailered to both the machine and application. So while I can easily cut cabinet parts at 1500ipm, any type of 3D work is a real struggle for the machine we have.

m_c
28-10-2017, 09:12 PM
What exactly is macro B?
Just the ability to have variables, and do calculations within the code?
If it is, Dynomotion KMotionCNC can do it, as they include some examples

It's something I've never had any dealings with, as most stuff I do on the lathe I just write manually, and the mill gets done using CAM.

Ger21
28-10-2017, 11:40 PM
Most controls can do some parametric g-code. But it appears that Macro B gives you access to just about every thing the control is doing, through variables.

Bravin Neff
29-10-2017, 01:14 AM
Most controls can do some parametric g-code. But it appears that Macro B gives you access to just about every thing the control is doing, through variables.

Yes, macro b isn't just variables, though it is that too. It also is access to system variables (eg., on a 2 pallet HMC, you can query: what pallet is currently inside?). Also, variables #1-#99 reset on power cycling, but #500-#599 do not. That is very useful for certain times you want information to survive regardless if power is interrupted. Access to just about everything in the control, and you can also have external I/O write to macro variables, depending on their state.

In the old days, people did their entire robot interface and gauging interfacing through m-codes and variables.

Bravin Neff
29-10-2017, 01:17 AM
Even to this day, if you buy a CNC machine that has a fanuc control (or one like it, like the Haas and Mitsubishi controls), and you want a Renishaw or Marposs probe, all the routines are written in macro b, and all the calculations and intermediate steps are just clever use of the variables.

Ger21
29-10-2017, 12:15 PM
Like I said, Mach4 Industrial is supposed to have full Fanuc B. I can't tell you what the current state of development is, though. I have a copy installed here, but don't see any documentation covering it.

I would say that it's highly unlikely that you'll ever see it on any other inexpensive controls, as the percentage of users that need/want is would be really small.
And the macro scripting in some of these controls is quite powerful, allowing you to do a lot of things.

Documentation on the Acorn is rather sparse, but looking at the docs on the website, in looks like you need to go to their top of the line controls to get the full Macro B.
The centroid manual that lists all of the variables says it's for the M39 and M400, which are over $11,000

m_c
29-10-2017, 12:28 PM
Thanks for clarifying that.

Similar things can be done with a KFlop, however not using any industrial standard.
I do have a Mach 4 Industrial license, however I doubt I'll ever use it. Dynomotion have no current plan to develop a Mach4 plugin, and the only controller that might temp me would be a CS-Labs, but I far prefer the flexibility of KFlops.

As Gerry says, anything that's not a true industrial controller, is not likely to ever have macro B.