Can't take it no more

[MrWild]

I'm going to be selling my BP I R-ram with Acroloop control. From day one it has been a headache of massive proportions. It needs an entire rebuild from top to botom. The head gear selection is loose to the Hi/Low lever which can be anywhere and engage hi or low. The engagement moves all around. The air brake lever from the cylinder to the brake knob is broke and a replacement (along with the adapter) are impossible to find. The Aussi draw bar can't be installed because finding a drawbar for the bridgeport that works with the aussie seems also impossible to find.

The ball screws are wore out and need either rebuilding or replacing. The nut yoke must be loose on the Y axis as I get a ridge of at least .015 when it changes direction while contouring. The ways are worn (out) and as they are chrome, I shudder at the cost of remachining them. Grind the chrome off, then hard chrome, then grind to size and scrape the chrome....

The control is great... when it works. It has a problem with seeing drives to load programs. Hit load program and tell it drive A: and it don't see the programs. Use library and it sees the programs. Play for a half hour to several hours turning off the machine and rebooting, going into save and delete protocals without saving and deleting and like magic A: will finaly appear. You'd think that solved the problem, but no, now it CAN'T see C: drive to load but it can see what is on it with the library key.

The Frequency drive works really great half the time. The rest of the time it comes up with "under voltage" even while reading balanced three phase of 232, 235, 235. When this hapens the spindle shudders with a pulsating force and turns slowly. You can stop it with your hand and it just pulses feebly.

I found a 1989 Supermax with Anilam Crusader-M controls that has maybe 1,000 hours on it. The paint, ways, control buttons and all areas that show wear with use still look factory fresh. It has a new monitor and spindle switch. I'm taking a loan on my life ins. cash equity and picking it up next week. What I can do with a working CNC really put a smile on my face and I haven't smiled in a long t ime. Well not like that. Why some people are such low life scum that they will lie to a deaf paraplegic and show off a machine in such a fashion to hide all of its flaws really threw me. For some reason I had assumed the world would toss me a break due to my circumstances and instead it showed me how naive I was. It just makes it easier for the scum to shake down a mark.

I'm jazzed about the Supermax though. Like finding a rare car with low miles just sitting and waiting for ya.

[ironDigit]

well mrWild

you'll have a hack of a time finding this pup a new owner
hers one from me : don't expect to make too much of a profit on this one

some way i always feel sorry when i hear this kind of agony being inflicted by a machinetool
good lukk m8

[Al_The_Man]

Sorry to hear it, if it had just been the Acroloop problem, I am sure I could have found a fix, as I have retrofitted a few.
Al.

[NC Cams]

Don't plan on selling your Acroloop system or the iron for very much to a 'Zone member, especially if someone reads your post.

It is truly sad that some machines turn into pit bulls. Sadly, this is due to poor installation (found that on the used NC equipment i bought), inept modifications to factory installations (found this on my NC equipment) and just plain old age (found that too).

Sadly, a lot of PC based retrofits and some so-called "industrial" systems are not properly fortified for use in a shop environment. Environmental contamination is a real problem as the solvents in a shop will corrode socketed IC's in an unbelieveable fashion. This is especially true with older equipment that has seen better days.

Vibration is another killer. A PC based HDD in a machine tool cabinet will last only a bit longer than one stuck onto a paint shaker. Ditto that for 'desktop PC' components fit to a machine tool cabinet. If a destop PC lasts for more than a few years in a shop environment, I'd feel lucky - to expect one to last a decade or more is not something I'd count upon.

We had some real problems with NC controllers in a shop environment and learned some lessons on keeping legacy equipment alive. They want/need cool dry CLEAN air circulating in them to keep them alive. If/when you start to get read write problems, start cleaning sockets and plugs - soft pencil erasers work.

On boards with socketed IC's, you sometimes have to pull the IC's and buff the pins to get the oxidation rubbed off of them. Plant to reseat them regularly, especaily if the 'snap' when you first try to reseat them. Sadly, the IC makers don't use gold plated pins which are the only ones I've found to be relatively impervious to corrosion in a shop. Neither do the board makers use gold plated sockets. Oh what could have been but ror a few pennies more per part....

After all of that, you run into old solder joints. Solder tends to corrode. Add repeated heatings and coolings and boards tend to warp and pull - solder joints get stressed and semi-conduct. The last ditch fix: careful resolder ALL the joints, especially if they use thru hole mounted parts.

I went thru these very same "will it run today" issues with some dated 1979 legacy NC equipment. After going thru these efforts, and fixing the hacked up modifications that a previous owner levied upon them (total rewire), the machines now are well behaved and run quite well and regularly and predictably. Hours of work in cramped spaces plus mind numbing resoldering of hundreds of tiny pins but it brought the equipment back to life.

The worn way issue is a little bit harder to fix with solder and maintenance -sadly, only newer iron in better shape will fix that.

Let this be a fair warning to the buyers of 'legacy' used CNC equipment buyers. You have an adventure lurking if you're not careful with your machine review and selection.

[Al_The_Man]

Originally Posted by NC Cams Sadly, a lot of PC based retrofits and some so-called "industrial" systems are not properly fortified for use in a shop environment. Environmental contamination is a real problem as the solvents in a shop will corrode socketed IC's in an unbelieveable fashion.

On the other hand, I have been fitting PC based controls since early 1990's in some really, really bad environment's, I refused to pay up to $8k for 'Industrial Strength' PC, I can replace alot for that money, I do however fit them in a positive pressure cabinet, using simple fan and filter arrangement.
I mostly have my own custom pendant or operator display cabinet made up at a local tin-shop, often fitting the whole PC in the pendant.
It sounds like in Mr_Wilds case, his problems were largely mechanical, as the Acroloop often comes with their all-in-one computer and controller as a unit.
These have been used my many large OEM's for industrial machinery.
Al.

[NC Cams]

When your controller has trouble finding A:\ or C:\ rendomly, you've probably got something going wrong with the machine's M/B or HDD.

If you have variable freq drive problems, it might be just a case of a loose ground or loose connectors or some other line malady. But, none the less, it happens.

When it comes to thermal expansion issue induced deteriouration of boards, it don't matter if you have sealed cabinet with heat exchange (what we had) or an semi open cabinet with a fan and paper air cleaner (ala my Bridgeport) - the boards need to be resoldered or replaced.

Even with a positive pressure cabinet, vaporous contamination will affect/corrode tin coated sockets and IC pins. Sadly, some control suppliers persist on using these cheaper components even when it is common knowledge that they don't live in a severe environment. Vaporous contamination will readily get thru a simple paper air cleaner.

Yes, industrial computers are pricey. Some are not much better than a PC and some are essentially bulletproof. Hard to say without specific experience which falls into which category.

My point is/was that PC base controllers can work quite well in industrial environments. BUT, in some situations, they can respond quite wierdly and unreliably. Especially as compared to their exact same cousins that are running in a clean office environment righ next door. If you know/recognize that, you can use it to your advantage when you go to troubleshoot one.

When read write errors start to develop with PC's, sometimes the best thing to do is to retire them.

What's really strange here is that the member clearly stated "...From day one it has been a headache of massive proportions " and "...The control is great... when it works...".

The iron issues asside - the control problems he cited quite possibly are the result of intermittant connection failures. These could have been the result of poor integration, poor maintenance, ill concieved modifications. contamination and/or old age.

The remedies to most of these issus were outlined in an earlier post in this thread. Or else the machine is truly haunted and has a mind of its own.

BTW: Our Fanuc's had that problem but we had the demons exorcised with a lot of cash therapy and TLC.

Regardless of true root cause of the problem, neither turning a maching off and on nor simply living with such grief will not resolve it - it generally tends to get worse without service.

Hopefully this thread will help other members who are contemplating the procurement of legacy CNC equipment. It could be haunted.

Sadly, getting service for or self servicing some older CNC machines is beyond the budget and/or technical skills of some owners.

[pastera]

All of my boards that are going into a harsh environment have the socketed ICs soldered into the sockets to prevent heat pop and are oven baked and immediately conformal coated. They HAVE been dunked in seawater and worked!

As far as storage - convert to solid state. A 4gig compact flash can be had for less than $150 and an IDE adapter is around $25. If you're not writing to the thing continously they last forever. The average life of the hard drives in my systems is about 6 months. By changing to compact flash the problem goes away.

The two killers are heat and vibration for my equipment. The compact flash handles both very well. A cnc controller cabinet is going to have the same issues


Aaron

[Al_The_Man]

Originally Posted by pastera The average life of the hard drives in my systems is about 6 months.

I guess I have been lucky with my installations, I don't remember replacing a hard drive under 3 years, and these are systems that are running two or three daily shifts.
One of the problems is I guess that whoever spec's in a machine should order the correct protection upfront, for example, in a highly corrosive atmosphere then the proper NEMA rated cabinets should be used including stainless.
If cabinet cooling is necessary, then a heat exchanger can be used to preserve the integrity of the NEMA rating.
Al.
http://www.conformity.com/0502/0502understanding.html

[NC Cams]

Al

I just read the link you posted in #8 to the NEMA cabinet specs.

I'll guarantee you that my Fanuc cabinets that my lathe controllers originally came in wouldn't pass those tests even BEFORE the OEM hacked into them. Neither would any of my much more current Bridgeport cabinets.

Once the machine tool builder finished his assault on the NC cabinet for the Fanuc and added the spindle motor drive/controller and/or the interconnect wiring, the things leaked like sieves.

That was my point about "poor integration practices" in an earlier post. Yes, there are integrators who DO try to pressurize the cabinets and are aware of the environmentals. But even seasoned "pros" are not that adept at fortifying cabinets for industrial use - great machine builders, poor control packagers.

Example: we just took delivery of an OEM, unhacked Bridgeport V2XT. It was in nice shape but had clearly been in a stamping shop where environmentals were NOT pristine.

The air filter for the controller cabinet was plugged solid - they had disconnected the cabinet fan, probably because it wasn't sucking anymore. Gee, I wonder why???. At least BPT put a filter there which was the proper thing to do.

Yet, when you look at the CRT, there was a fan that sucked cooling air INTO the CRT cabinet - thru a louvered baffle (with no air filter) which is what BPT did, no more no less.

From the glop on the muffin fan on the CRT pendant, the glop that had plugged the cabinet filter clearly had been drawn INTO the CRT cabinet, thru the louvres and was now adhering to the fan - goodness only knows what the inside of the cabinet looks like and I shudder to take the cover off to look!!! If it don't stink, don't stirr it, I guess.

Point remains, why did BPT properly put a filter on the PC cabinet to screen out shop debris in the air yet they failed to to the same thing to the CRT which needs the same quality of air???

My belief: Pizz poor engineering, pizz poor integration, pizz poor economics and just outright ignorance and/or stupidity from an outfit that clearly should have known better.

Too bad Bridgeport didn't know of or had the NEMA specs you posted available to them in their day. Maybe they'd still be a profitable, viable machine tool business as opposed to merely a brand name owned by Hardinge.

Good info in that post. Anybody who plans to put a PC into a shop environment needs to study it.

[Al_The_Man]

What I have done on a couple of jobs where the environment was bad, was to make up a simple air exchanger, I placed a length of 6" wide aluminum heatsink extrusion the full length of the top of the cabinet, (which is where the hot air rises to).
Welded aluminum plate across the ends, this leaves a sealed chamber the full length of the cabinet, then cut a circular hole in the cabinet top each end of where the chamber came to and mounted a 6" dia fan over one hole, which results in air being blown through the chamber cooled and re-enter the other end.
The whole thing is sealed to exclude air and the heatsink fins radiate off the heat.
The NEMA rating is preserved with a sealed cabinet.
Al.