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SMW Precision
11-19-2006, 08:00 PM
I have just finished the Mechanical installation part of my Industrial Hobbies CNC retrofit kit. In this case on an Enco RF45 mill/drill. I am going to try to give a fair evaluation of the kit as I complete major sections.
This kit is Aaron’s latest version. First element of these kits is number of boxes delivered in my case it was 7 different packages. When opened each different part assembly is packaged, labeled and specialized instructions are included within many of those bags.
I had originally thought too build my own system there are lots or mill/drill plans out there. I purchased this kit after examining everything I could find. Along with going through groups and studying the technology. For me it has been a several year process with a long way to go before I will feel comfortable in CNC operation.
Kit installation directions are excellent in providing information needed. They reflect a lot of experience with many users. Parts included in this kit are meticulous in both machining and quality control. After installing the mechanicals it became clear to me how silly a complete system build would have been for me. I would have exchanged 1000 to 1500 dollars in possible cost savings for a 150 to 250 more build hours. What I would of ended up with would of been a much lower quality of system.
It is very obvious that Aaron has thousands of hours of thought and design experience in these kits. There are no weak spots that I could find ¾” ballscrews, powerful motors and heavy duty installation brackets. System is beautifully designed to operate in a fluid coolant environment.


Ken

wildcat
11-20-2006, 12:28 AM
Have to completely agree with Ken on the kit. Wished some Loctite had been included but that was the only thing that I needed to pick up from town. A couple of items were not included but Aaron took care of that fast (one was shipped before I know it was missing). Also he replaced a couple of items where I had screwed up. That's service!

Below are some pics of what $4200 gets you. A little dissappointing on the quantity perhaps but I am very happy with the quality. :) The transformer arrived a little later (not shown here) mounted to a wooden support in a big box.

http://www.cnczone.com/gallery/data/500/medium/CRW_3635-1.jpg
http://www.cnczone.com/gallery/data/500/medium/CRW_3636-1.jpg
http://www.cnczone.com/gallery/data/500/medium/CRW_3637-1.jpg

SMW Precision
11-20-2006, 01:47 AM
Wildcat,

Great pic's I did not take a set. Have you completed your installation yet? I found an a lot of parts in those bags. There must of been close to 250 fasteners. Encoders and covers alone had 13 screws each.
At least for me a key advantage of this kit after putting it together is knowing how to repair and service it. As most of us are aware most Chinese tools require some tweaking.

Ken

wildcat
11-20-2006, 10:37 AM
Ken - I have everything together and on except for the limit switches and shields which were shipped separately. The power supply/controllers/breakout board are mounted on a piece of MDF until I can make or locate a suitable enclosure. This weekend I trammed the mill which required shimming the column or the head. I have the old style head though and tightening those boles is a pain. Anyway, it was great to mount a test indicator, zero it out against a stop, rapid away and then back and find the test indicator dead on zero for all axis. Doing very small movements (<10 thou) was a different story but still good. I did goof-up in a few spots. I cut the Y ball-screw .25-.5 inch shorter than I should have. The ball screw must not have been completely slid into the Y assembly when I measured. Also, the Y-axis ball-screw is at a slight incline but this does not seem to affect the Y-axis movement. [If necessary I will remount the Y-axis assembly - no way am I going to try to shim the Y-axis bracket. It baffles me why Aaron suggests on the IH mill to cut the back of the bracket off and insert a bolt from the top side of the slide. If you ever want to remove the bracket the table has to come off. Also, if I had left it full size my undercut ball-screw would have come past the wiper.] I cut the base a little to increase the Y travel which turned out to be completely unnecessary. I forgot to put the chip guard back under the saddle (though I don't see it in Aaron's shots either - perhaps it can jam?) Cut the X-axis motor wire short (that axis moves :) And I forgot the cut the strut out of the front of the column and had to do that after mounting the head and find that it was not possible to get the head down to the table. Also, the SIIG card I got kept locking XP up for some reason - the built-in parallel port on this Dell seems to work fine though. Seems like a long list but nothing too tragic. Cutting the ball-screw short is a little sickening at the time though. Been cutting a lot of shapes into MDF to get the hang of everything and have really been enjoying it.

SMW Precision
11-20-2006, 07:02 PM
Sounds like you are getting close to completion. I think on electronic's box I am going to just form it myself likely light gage aluminium. Ordered B/O board today with VFD and fluild control. I purchased a C11 board at CNC4PC.
Talked too Aaron about these boards and he did not like any of them. So I guess I will see if board will work. This week I need to complete mill enclosure or at least make some progress. Stand is done and I need too form an aluminium pan. Likely use 1/8th inch plastic for walls; I need to be able to pull enclosure apart. So it will be built with ability to be disassembled.

wildcat
11-21-2006, 12:11 AM
Ken - did you get a sense from Aaron why he dislikes the breakout boards? Not knocking his kit but the suggested wiring seems a little limited on safety features (not to mention hard to read). The geckos reset after a fault without shutting Mach down, there is limited isolation, no charge pump protection, emergency switch, etc. It is nice to keep the price down but I would not have minded paying a little extra to have the electronics well packaged and safe.

SMW Precision
11-21-2006, 12:40 AM
Wildcat,

It was several months ago I talked to Aaron about boards. He mentioned he was going to offer boards for VFD and pump. I asked him to let me know when they were available; I have not yet heard back from him. I know they are not listed on website.
From our discussion I got the feeling from Aaron various boards have caused him support problems. He was not big on opto isolation either.
I wish he would find a set that works well and at least reccommend them. Kit is designed for VFD and fluid pump. It would be nice if a box and the rest was an available option. Frankly electronics are not one my expert areas though I have support if needed.

Richards
11-21-2006, 02:16 AM
Let's discuss opto-isolation a little. In my designs over the last thirty years, I've almost always used opto-isolation. With well over 100 designs that ended up as fabricated circuit boards, that's a lot of design time (well, some of the designs were simple little ten-minute things). When I hear that someone doesn't like opto-isolation, it usually comes down to them not wanting to install extra power supplies - or even worse, using the same power supply on both sides of the opto-coupler, which defeats the opto-isolation. If we understand it, it is a wonderful and wonderfully easy concept. With opto-isolation, there is NO copper connection between the computer and the controller. There is only a light going on and off to transfer the state of a signal from one device to another. With opto-isolation, when used properly, most of the electrical interference problems that plague industrial electronics can be eliminated. The common opto-couplers like the TIL-111 are available for a few cents each. Granted, there is a signal delay involved, usually about 5us, and there are some current requirements, usually about 10ma, but both of those factors are common with a lot of TTL circuits.

They're very easy to use. For instance, with a TIL-111, you can connect pin 2 to your active LOW signal line. You connect pin 1 to a resistor (330 ohms is a good starting point). You connect the other end of the resistor to +5VDC. When the signal goes active (LOW), the internal light turns on. On the other side of the circuit, you connect pin 4 to ground. You connect pin 5 to another resistor (2,200 ohms to 4,700 ohms usually work fine). The other end of the resistor is connected to a separate 5VDC supply. You also connect the device you're sending the signal to, to the junction of pin 5 and the resistor. In a typical TTL circuit, you're ready to run. Assuming that everything in the circuit works off an active LOW signal, when the input circuit goes LOW, the internal light turns on. When the intermal light turns on, the internal light detector turns on. When the internal light detector turns on, the internal transistor turns on, and the voltage on the Collector drops to zero. Thus, an active LOW input signal produces an active LOW output signal.

The beauty of the system is that if something happens on the controller side of the circuit, like fluid splashing the electronics or metal chips shorting out the electronics, you might burn up the controller, but your computer is safe. On the other hand, if your computer decides to take a dive, it might fry, but the controller is saved.

Some breakout boards have opto-isolation built in. If they do, you won't have to add your own circuits. To me, one of the main advantages of using a breakout board is that I don't have to build high-current step/direction circuits to drive the Gecko's step/direction lines. The documentation that I have states very clearly that the Geckos need 16ma of current to work properly. In the TTL world, 16ma is a lot more current than most TTL circuits need. In fact 4ma to 10ma are much more common than 16ma. Parallel ports, in my opinion and with my experience, can't be counted on to supply 16ma. That means that the step/direction signals might not pulse when they're supposed to. That also means flakey behavior and possibly missed steps. Do yourself a favor. If you're spending the better part of $10,000 to buy a mill with CNC controls, a computer and some tooling, buy a good quality breakout board for about $100.

wildcat
11-21-2006, 03:02 PM
Richards - points and experience well taken. I thought of making my own isolation but after reading the Sound Logic documentation that pointed out the danger of not being careful with the power supply (as you pointed as well) I decided that isolation is an area best left to experts instead of those like myself that know enough to talk about electronics but obviously not enough to build something from scratch. I also did not know about the current requirements of the input lines on the Geckos. Perhaps this partially why some have so much trouble with built in PPorts and laptops?

Thanks

Richards
11-21-2006, 10:48 PM
Sometimes it's difficult being the owner, operator, bill collector, maintanence man, designer, and errand boy all wrapped up into one person. When I started my first business, I was totally overwhemed by all of the 'little' time consumming tasks that kept me from doing the necessary things. After talking with a friend, who had an MBA and worked for one of the large utility companies, he just laughed and said that most companies have whole departments for each of those 'jobs'. Welcome to the world of the small business person.

The amount of knowledge that we have to have to make these machines work and work profitably, is almost overwhelming. Many who have the answers are just a little timid in sharing those answers with the rest of us. Hopefully, that timidity will pass and we'll all benefit from the vast experience that is out there.

IndHobby
11-22-2006, 12:14 PM
Personally I like optical isolation, so lets look at the basic issues.

Geckos and Limits.

Geckos are optically isolated onto themselves.
Optcal Limits are optical isolaters, take one apart and look.

If you follow the basic schematic and steal the control power from the PC you will be isolated.

Insofar as the motor and coolant. The SS relay I use is optically isolated as well and can be driven right from the PC. Solves that problem as well.

We do use Bob's VFD controller board, it can be used by itself, and to my knowledge can be isolated as well just by using a seperate PS on the VFD side.

I have helped troubleshoot more than one breakout board problem over the phone and it starts getting real old real fast, so have a hard time reccomending them to a customer.

The other problem I have with a breakout board is the real estate it takes, they are huge. If we are concerned with chips or coolant getting in the wrong spot lets not see how big of a target we can provide.

My first machine is all wire to terminal connections, just hard wired, nothing fancy. And it looks so bad I would never post a picture of it, it was just a concept and I always figured I would go back and rewire it later. Later never came. But she just keeps chuging along, about once every 6 months I blow out all the stray metal chips and leave it alone.

The point I'm making is that simplicity is a quality onto itself, simplicity usually brings robustness another quality I like.

Just my 2 cents worth.

Runner4404spd
11-22-2006, 12:31 PM
i make it a point to mount my break out board upside down in the case as well as other electrical devices. everything mounted on the floor of the case is either shielded or covered to prevent shorts from chips.

SMW Precision
11-22-2006, 01:24 PM
[QUOTE=IndHobby;220790]Personally I like optical isolation, so lets look at the basic issues.

Geckos and Limits.

Geckos are optically isolated onto themselves.
Optcal Limits are optical isolaters, take one apart and look.

If you follow the basic schematic and steal the control power from the PC you will be isolated.

Insofar as the motor and coolant. The SS relay I use is optically isolated as well and can be driven right from the PC. Solves that problem as well.

We do use Bob's VFD controller board, it can be used by itself, and to my knowledge can be isolated as well just by using a seperate PS on the VFD side.

I have helped troubleshoot more than one breakout board problem over the phone and it starts getting real old real fast, so have a hard time reccomending them to a customer.

The other problem I have with a breakout board is the real estate it takes, they are huge. If we are concerned with chips or coolant getting in the wrong spot lets not see how big of a target we can provide.

My first machine is all wire to terminal connections, just hard wired, nothing fancy. And it looks so bad I would never post a picture of it, it was just a concept and I always figured I would go back and rewire it later. Later never came. But she just keeps chuging along, about once every 6 months I blow out all the stray metal chips and leave it alone.

The point I'm making is that simplicity is a quality onto itself, simplicity usually brings robustness another quality I like.

Aaron,

Thanks for the comments they help! The other Key question that has come up is wattage capabilities of PC for supplying Gecko drivers boards. Are they a mismatch?

From; Richard
The documentation that I have states very clearly that the Geckos need 16ma of current to work properly. In the TTL world, 16ma is a lot more current than most TTL circuits need. In fact 4ma to 10ma are much more common than 16ma. Parallel ports, in my opinion and with my experience, can't be counted on to supply 16ma. That means that the step/direction signals might not pulse when they're supposed to. That also means flakey behavior and possibly missed steps.

Having recently been through computer power supply issues this is of concern to me. There are huge variances between computer power supplies in quality and wattage capabilities. From the bottom end $15 PS on up!

What are your thoughts on PS issue?

IndHobby
11-22-2006, 01:40 PM
Thanks for the comments they help! The other Key question that has come up is wattage capabilities of PC for supplying Gecko drivers boards. Are they a mismatch?

***Not an issue, a PC has far more juice than you will need, all the little parts were talking about here draw less than a second hard drive.

From; Richard
The documentation that I have states very clearly that the Geckos need 16ma of current to work properly. In the TTL world, 16ma is a lot more current than most TTL circuits need. In fact 4ma to 10ma are much more common than 16ma. Parallel ports, in my opinion and with my experience, can't be counted on to supply 16ma. That means that the step/direction signals might not pulse when they're supposed to. That also means flakey behavior and possibly missed steps.

*** USE a SIIG CyberParallel card, off the top of my head they will source 20ma and sink 50ma per line. It's what all of us guys use.

Having recently been through computer power supply issues this is of concern to me. There are huge variances between computer power supplies in quality and wattage capabilities. From the bottom end $15 PS on up!

*** Please do not cheap out on the powersupply, spend the $50 for a good one and it will last you forever.

Richards
11-22-2006, 04:48 PM
Aaron,

I guess that we'll have to agree to disagree on breakout boards. After reading your posts, I downloaded documentation for Bob Campbell's board and then reread the documenation to the PMDX board that I use. Both sets of documentation seemed to be standard stuff that would work if followed. Granted, because all of our backgrounds are different, what seems standard to me might be something else to others - and vice-versa.

Some of the boards are large, others are fairly small. The PMDX that I use measures 3 x 4-1/2 inches, which, I believe is small enough to fit in most boxes. Speaking of boxes, I've always assumed that anyone adding CNC controls to a mill would use an enclosure that would protect the electronics in a liquid environment. Maybe I'm expecting too much, but it just seems logical that, if there is water present, the enclosure has to keep the water and chips out. Enclosures come in all sizes. Getting one big enough to include a breakout board would also guarantee that the case would be big enough to dissipate the heat generated by the Geckos and the power supply.

The SIIG board that you referenced would probably solve the low-current problem with parallel ports built into motherboards. I visited the SIIG site. Their documentation was good, but it didn't list source and sink current capabilities of the card, other than to state that the card adhered to standards. I think that we agree that a built-in parallel port might not work properly. But, wiring things to a DB-25 connected is not fun. My old eyes have a hard time seeing solder bridges between adjacent connectors. Buying a proper crimp tool for $125 so that crimped pins can be used instead is about $40 more than a breakout-board. I've built litterally hundreds of cables over the years using DB-25 connectors and making wiring errors was a common problem. One of the more tiresome tasks was to beep out new cables using a meter that beeped when shorts were present. (There was a day when terminals, such as the Wyse-50 and Televideo 950 were connected to computers via an RS-232 cable. Since there was no wiring standard, it was easier to make a custom cable than to try to buy cables ready-made.)

My thought is that wiring a parallel port directly to devices means that I have to have higher skills and knowledge than simply connecting wires to screw terminals. In other words, plugging one end of a parallel cable into my PC and the other end into my breakout board, and then connecting cables between my breakout board and the various devices that I'm controlling seems pretty basic to me with little chance for error.

I haven't ordered your CNC kit yet, so I don't have your wiring chart, but I'm sure that you've written your instructions clearly. Your web site is outstanding and the machines that you demonstated for me at IH show that you really know what you're doing. So, without looking at your documentation, I would assume that anyone following your instructions would have no problem connecting electronics in a basic system. The potential for problems would seem to be adding other input sensors or output devices that might not be opto-isolated to the system.

We agree that the Geckos are opto-isolated and that your limit switches are opto-isolated, so we don't have to worry about them, but, those other devices that people add to their mills that might/should cause concern. A breakout board solves that problem.

Adding opto-isolators to everything might be redundant, but it would guarantee that everything is truely isolated. The danger in that approach is adding extra isolated power supplies for each level of opto-isolation. A big problem, when using opto-couplers is that one side of the circuit has power and the other side is dead. Some people try to get around that probjem by using a common power supply to power everything. Bad idea. That defeats the isolation. Adding a couple of small 5V power supplies is easy. Jameco has inexpensive supplies that are the size of a credit card and less than 2-inches tall.

Building a good CNC system takes a lot expertise from a lot of disciplines. You have the knowledge and experience to do it all. I have some experience in electronics. Others may have more experience or less than I. Sharing experience and concerns might help the unwary get past the gotchas that seem to be lurking just beyond the line of sight, waiting to mess things up.

SMW Precision
11-22-2006, 05:47 PM
Building a good CNC system takes a lot expertise from a lot of disciplines. You have the knowledge and experience to do it all. I have some experience in electronics. Others may have more experience or less than I. Sharing experience and concerns might help the unwary get past the gotchas that seem to be lurking just beyond the line of sight, waiting to mess things up.

Richard,

I could not agree more! I have been thinking about this discussion. Too a great degree I think everyone is right. One of the things Aaron did a couple of years ago was design an excellent heatsink system for those Gecko drivers.
I think this may be why operation problems are not occuring.

wildcat
11-22-2006, 07:56 PM
When I was reading about isolation I also read that the Geckos and limit switches are isolated. However, the wire leaving the devices are not. For instance, the isolation in limit switches does nothing if a short occurs long the length of wire back to the enclosure. A number of bad things would have to happen for this to become catastrophic but the breakout board seemed to provide cheap insurance.

IndHobby
11-22-2006, 08:45 PM
Metal cases for all the “stuff” is pretty expensive, and for the most part an old PC case works just fine. Unless something is reasonably priced folks will use what works, a NEMA enclosure runs about $250 (yea it’s big) a old PC case is about $20.

Insofar as skills to wire one or the other, who knows, I honestly think a direct wire is easier. I’ve done complex, and I’ve done simple. I prefer the simple.

For the most part I get only a few wiring questions so I guess the basic schematic is doing ok:

One funny story:

I had a customer who had an axis running away. We went over possibilities, he checked this and that and it still ran away. I sent a new Gecko and encoder (I think he swapped them both) it still ran away he checked every wire, it still ran away.

After about 7 hours on the phone over a week period he mentioned he was color blind. I asked if anyone else was home. He got his daughter out of bed and brought her down to the shop. After introducing myself I had her tell me the color of the wires in order. After she told me the color of the eighth wire I had it. He had swapped the green and brown wire (Index instead of Phase A). He was running in 30 minutes.

The moral of the story?
It is easy to fix simple, when you have a product from one vendor, connecting to a product from another it gets real messy real fast.

IndHobby
11-22-2006, 09:08 PM
Yes Wildcat, if enough catastrophic events occur at the same time all hell can break loose, at which point if they are catastrophic enough they will happen on the isolated side of the circuit, or the other side. Whatever side you are trying to protect. There is some weird law out there which states that eventually the sum of your fears will come true, it is just a matter of time.

On the other hand, the more complex a circuit the higher the possibility of it being its own problem. The goal is simple, simple, simple.

I was electronic warfare in the Army for 6 years. Worked on everything electronic you can imagine. Simple ALWAYS lasts longer than complex.

This is one of those electron flow/hole flow arguments (if you understand that you are a geek) there is no single right answer. Just shades of wrong.

The long and short: On a Saturday afternoon with a Marlboro in one hand and a beer in the other, I can walk someone through a wiring problem and get it solved over the phone. Throw a few breakout boards and it becomes a whole new problem.

And it’s not that I have anything against these breakout boards, they are just not my thing.

Richards
11-22-2006, 11:02 PM
Sometimes it's a hard decision knowing what to do and whose opinion should be listened to. I'd rather go with an expensive case ($250) to protect a $10,000 investment than trust to luck with a $20 case. That's just me. I've lived long enough that scrimping on hardware no longer makes sense. There is probably no 'one way' to make things perfect, but I'll almost always go with either 'standards' or 'industrial accepted pactices' as my model. One thing that I've learned over the years is that you can always tell a pioneer by the arrows in his back. In other words, I'd rather be safe (and spend the dollars) than sorry. It all comes down to 'insurance'. I have a rather large life insurance policy to protect my wife and family. I'm betting that I will die before my time and the life insurance company is betting that I will beat the odds and live at least as long as they predict. It's the same way with health insurance. I pay $10,000 a year betting that either I or someone in my family is going to need major medical insurance. So far, I've paid out more than $70,000 in premiums to save $11,000 in actual costs. So, I'm wrong. Perhaps it's my nature, but I tend to play it safe and follow all accepted rules - regardless of the actual possibility for failure. In actual costs, spending an extra $300 to $500 on a CNC upgrade to protect a $10,000 investment seems reasonable to me. Others may think otherwise. Please note that I have the highest regard for Aaron and the machinery that he sells. My opinion on how to hook up that machinery are just that - my opinion. He has proven himself over the course of years and I'm a totally newbie - although I'm a cautious newbie.

-Mike Richards

Ron111
05-22-2007, 08:06 PM
Ken,

It's been a good six months since you finished the mill, I also has looked at the enco since it is on sale so how is the mill working out. I would love to see some pic/s and hear about it's performance and any associated issues.

Thanks,

Ron

SMW Precision
05-25-2007, 02:12 AM
Ken,

It's been a good six months since you finished the mill, I also has looked at the enco since it is on sale so how is the mill working out. I would love to see some pic/s and hear about it's performance and any associated issues.

Thanks,

Ron

Ron,

Mechanicals are excellent in the IH kit. Where I had problems and got fixes were the electronics. All the bugs are out, Aaron as usual was right don't use the breakout boards. As well as a few other tricks part his and a few of mine.
Listed performance spec's are extremely conservative while the IH system will run literally forever at 105 imp it is capable of over twice that IPM movement rate. Tooling, setup and gcode all play a role in performance.
I personally cannot suggest doing the conversion on a RF45, mine was purchased before the first IH mill shipment and there have been a great number of improvements from that point on the Mill.
Current IH mill is several times more rigid than the RF45 with twice the work envelope. I also ran into problems on Z-axis slide connector to ball nut when cut for ball nut this under sized casting becomes way to thin. Servo motor shattered it like it was not even there. I made a mistake on limit switch setting and replaced it with one about 10 times heavier. Thank you Gene & Tommy for helping to fabricate a replacement. That thin casting also affected Z-axis accuracy. I believe further kits sent out for a RF45 will contain a replacement for that part.

Ron111
05-27-2007, 04:18 PM
Ken,
Thanks for the insight, your right it would pay to get the more ridgid current IH mill. Are you where your are happy with your mill and how much use does it get now. But your signature it appears that you may be using the mill for so type of manufacture of a product. I guess that's what a lot of us who read the zone are interested in in whether some of these benchtop mills are being used is some daily use whether it is in producing small proction runs of this or that and who they are holding up on a daily basis. Maybe I should start a new thread and poll the cummunity.

Thanks for your input,

Ron

SMW Precision
05-29-2007, 11:41 AM
Ron,

My usage is fairly minor; basic parts runs. Though I know of one shop that just ordered their 3rd machine. They run them daily for many hours doing general CNC machining.
Aarons original prototype mill is still cutting straight with 10 to 15,000 hours of operation. It cut all the IH parts for about 5 years and still is used to cut several speciality parts. There has been a lot of progress from that mill with a stepper Z-axis built from an Enco RF45.

Ken