I just found out my servo drivers are analog +10/-10 v What are my options?

[Setlab]

I had a pretty big hit to my wallet today I think, I'm doing a retrofit on a mill planning on using the existing servo motors and servo amp controllers (made by Glentek) and I just found out they are analog input whereas I need a step and direction input to run off Acorn.

Do components that will adapt a step and direction signal to analog +10/-10v exist? Or do I have to buy brand new drives? If I do need to buy new servo drivers can someone recommend a place to buy some cheap Chinese-made components? My current servo motors and drives are powered by a 160vdc power supply, the small axis servo motors are 48oz-in and the spindle drive is a 30lb-in servo. This small benchtop mill is turning into a money pit

Could an option be to keep my old drives and buy a much more expensive oak or allin board that appears to allow analog signal output?

[cncsnw]

You could probably use the existing drives with an MPU11 and GPIO4D (a better fit than the Oak, for Glentek analog drives). Still better, it is likely you could use the Allin1DC to run the existing motors, and ditch the analog drives.

I believe there are also DC servo drives available that receive step-and-direction input, and of course monitor the axis encoders and do position control themselves. Others here can probably identify makes and models, and offer any experiences.

[knastenrad]

could this do the trick?

https://www.audiohms.com/en/cnc-electro ... -dcs-100-a

[Muzzer]

A few of us are using the cncdrive DG4S https://www.cncdrive.com/DG4S_16035.html

These take step/dir inputs and drive DC brushed motors. You need to check you have encoders in your motors (rather than resolvers). I've got 3 of those on my bigger machine and they have been fine. You can buy them in the US or EU depending where you live, to avoid import duties etc.

[martyscncgarage]

I had a pretty big hit to my wallet today I think, I'm doing a retrofit on a mill planning on using the existing servo motors and servo amp controllers (made by Glentek) and I just found out they are analog input whereas I need a step and direction input to run off Acorn.

Do components that will adapt a step and direction signal to analog +10/-10v exist? Or do I have to buy brand new drives? If I do need to buy new servo drivers can someone recommend a place to buy some cheap Chinese-made components? My current servo motors and drives are powered by a 160vdc power supply, the small axis servo motors are 48oz-in and the spindle drive is a 30lb-in servo. This small benchtop mill is turning into a money pit

Could an option be to keep my old drives and buy a much more expensive oak or allin board that appears to allow analog signal output?

Would really like to see pictures of your control cabinet, labels on your drives and motors, what kind of spindle drive if any do you have?
And a picture of the overall machine and its condition. History of the machine? Did you own it working and the control suddenly died or did you buy the machine with a dead control in the hopes of fixing up for hobby OR for full time commercial for profit use?

For example, I just retrofitted a Clausing Kondia knee mill, I was going OAK and DMM AC Servos until I found that the frame of the DMM AC servos would interfere with the table, alerted by another user who had this problem. I did not want to "hack" at the table and decided to backtrack and put DC Brush Servos back on and go the All in One DC route. True closed loop motion controller.

Marc Leonard offers another Centroid closed loop solution, MPU11 and GPIO4. I think it has some complexities.

The other issue, how much experience do you have with CNC conversions? Do you have reasonable electrical/electronic background to carry out a simple conversion or a bit more challenging conversion?

What is your desired result? What is your budget? I estimated my first All in One DC conversion in parts alone to be about $4k by the time it was said and done, BUT that machine was pristene and I felt the money was a good investment, and it turned out to be so.

When you move to bigger machines, the budget goes up.

Share with us your thoughts and details about the machine, we're always happy to give you an opinion. I hate to see two things, 1. Someone starts a conversion and can't see it through, project turns to scrap. 2) Person looks at the bare cost of a control and doesn't add up EVERYTHING involved and either #1 above happens or they pour so much money into the machine, that they can't recoup the cost because the machine isn't worth it or find out the machine needs mechanical fixes. So, continue to do your research and make the best decision for you.
Marty

Marty

[Setlab]

Would really like to see pictures of your control cabinet, labels on your drives and motors, what kind of spindle drive if any do you have?
And a picture of the overall machine and its condition. History of the machine? Did you own it working and the control suddenly died or did you buy the machine with a dead control in the hopes of fixing up for hobby OR for full time commercial for profit use?

For example, I just retrofitted a Clausing Kondia knee mill, I was going OAK and DMM AC Servos until I found that the frame of the DMM AC servos would interfere with the table, alerted by another user who had this problem. I did not want to "hack" at the table and decided to backtrack and put DC Brush Servos back on and go the All in One DC route. True closed loop motion controller.

Marc Leonard offers another Centroid closed loop solution, MPU11 and GPIO4. I think it has some complexities.

The other issue, how much experience do you have with CNC conversions? Do you have reasonable electrical/electronic background to carry out a simple conversion or a bit more challenging conversion?

What is your desired result? What is your budget? I estimated my first All in One DC conversion in parts alone to be about $4k by the time it was said and done, BUT that machine was pristene and I felt the money was a good investment, and it turned out to be so.

When you move to bigger machines, the budget goes up.

Share with us your thoughts and details about the machine, we're always happy to give you an opinion. I hate to see two things, 1. Someone starts a conversion and can't see it through, project turns to scrap. 2) Person looks at the bare cost of a control and doesn't add up EVERYTHING involved and either #1 above happens or they pour so much money into the machine, that they can't recoup the cost because the machine isn't worth it or find out the machine needs mechanical fixes. So, continue to do your research and make the best decision for you.
Marty

Marty

The mill is a Dyna Myte DM2800, it's a pretty small benchtop machine just a little it smaller than a tormach 440. I just finished taking everything apart and putting it together after a good cleaning and replacement of consumable parts. All the machined surfaces that weren't surface ground still have the 'scraper' marks. I bought the mill at an auction and paid a little too much thanks to an impulse buy and one other bidder that I really don't like right now lol. In a previous life, the mill looked to be only used to machine brass as nothing but brass shavings were compacted all over it when I tore it apart. Ball screws look and feel great too. The not so good, the table and z-axis ways had some surface rust that I carefully removed, you can't see staining on the z-axis any longer, but the table does have some 'pitting' where the rust ate some of it away. My solution was to buy a saunders machine tool fixture plate, with that I don't think I'll ever notice a couple of spots on the table that are lower than the rest. Also, the BT30 spindle taper has some galling in it that needs to be resurfaced. I just brought the spindle to a machine shop today for a quote on regrinding it.

I stripped everything out of the electrical cabinet to clean and start fresh with wiring so that picture is pretty underwhelming at the moment. I have 4 glentek drives and a working 170vdc power supply, which was all I was planning on saving.

I'm going to be pretty stubborn with this mill, I promise you it won't end up as a pile of scrap parts. Even if my last option is to spend another couple grand on it I'll do it begrudgingly eventually before the end of the year. My budget is pretty tight, I'm a college student so this is the biggest purchase I've made in a long while, actually, it will be my most expensive tool I own when all is said and done lol. I'm motivated to get it done and learn how to do it as an engineering project I can boost my resume with, that was/is my biggest motivation to buy get the mill up and going. It will mostly be a hobby machine, but I do plan on making small batches of widgets I can design and sell (more resume bullet points). My space is really limited so this size mill is about the biggest machine I can get away with right now, it will probably be something I will never sell so trying to recoup a bunch of lost money isn't going to cross my mind. I paid about $2400 for the mill after a bidding war that should have stopped at $800 but it is what it is and I wanted a CNC mill lol. Add in the acorn board, mill pro, digital probe, a bunch of bt30 tooling, a fixture plate, and probably a couple of other things I'm not thinking about right now the cost is adding up fast! Thankfully as far as tooling is concerned I have all that I need unless i come across something I just have to have.

This is my first venture into real CNC controls/retrofits outside of 3D printing and just general knowledge gained reading about the subject over the years, which is probably not too much lol. The most I've ever dove into electrical theory is a Circuit Analysis class I had a couple of semesters ago so it's still mostly fresh in my mind. I'm a mechanical guy so electrical anything really isn't my favorite subject if I have to wrap my head around complex circuits, I can do it but I really don't wanna.

[martyscncgarage]

Pete should be your inspiration

[martyscncgarage]

I do not think I would keep the DC brush motors on that machine. I would stick with a new closed loop drive/motor solution. What is the spindle motor drive? Glentek? Can you post a link to the manual?

[Setlab]

I do not think I would keep the DC brush motors on that machine. I would stick with a new closed loop drive/motor solution. What is the spindle motor drive? Glentek? Can you post a link to the manual?

All 4 drivers are Glenteks

Axis manuals: https://www.glentek.com/download/sma811 ... wpdmdl=379

Spindle manual: https://www.glentek.com/download/sma811 ... wpdmdl=357

Why would you scrap the motors too?

[Setlab]

I'm going through looking at the options you guys have posted slowly.

Has anyone dealt with viperservo.com out of Canada before? They make a servo drive that would work as well as a $90 step/direction to analog converter that would allow me to use my current configuration supposedly. http://032c30a.netsolhost.com/catalog/p ... ucts_id/56