[samco]

What version of emc are you using? Have you updated to the latest? If you just installed the livecd and not updated it you are running 2.4.3. there have been a lot of fixes since then. If you look here

LinuxCNC Documentation Wiki: Released

You can see that 2.4.5 relaase had some fixes (and past that there are a lot more)

pncconf: fix inverted encoder
pncconf: fix following error when inverting servo direction

Maybe that is your issue? I have not used the pncconf.. You really also should get comfortable editing the hal and ini files also. The pncconf though will give you a good starting point.

sam

[samco]

Yes - you want to enable the drives when the actual axis gets enabled. (when you turn 'on' linuxcnc) That way the drives get enabled at the same time the pid loops and such get enabled. Or you will get drifting.

sam

[samco]

Also - you should be able to get these drives to work satisfactory.. You will learn a lot about PID tuning

sam

[erikjgreen]

Well, I had been using the 2.4.3 version of linuxcnc (got to get used to typing that name). So the bug was still there. I'll update the software before I try again. I had read that I shouldn't update the ubuntu system as a whole... is that not right?

But I also talked with a couple people about the whining noise, and found out it's normal for those drives, IE I'd have to put up with it. Since my shop is small, and since I could hear it from the other end of my house (attached to the shop) I decided I'd have to change them.

So I ordered 3x Dugong drives and a programming stick. They should be here this week sometime. I think they'll be easier to tune for me, plus no whine!

I suppose I could also increase performance, since the servos can take 120 volts, but the old drive could only do 100, so I may up the power supply voltage, depending.

The drives can actually do up to 160 volts and 35 amps, so I could even replace my servos at some point with bigger ones if I wanted.

I could spend more time with the SD1525 drives, but frankly I'm more interested in spending time getting the mill cutting metal than in servo amp tinkering. I still have a lot of work to go, from the enclosure to the coolant tank and 4th axis, so I don't want to spend more time on the old drives.

If I can sell them, I will, otherwise I suppose I could keep them for later use on another CNC for use in my detached garage, like a router table or something.

In other news, I did pretty well at a local surplus store over the weekend. I picked up a brand new NSK 25mm ball screw support for $50, and an ABB ACH50 VFD sized for a 20 hp 3 phase motor for $30. I'm pretty sure the vfd needs work, but if I can repair it for less than $500, I'm still ahead of the game. I wish I'd been able to find two of the ballscrew supports, since I have two 25mm ball screws I'm going to use in a lathe, but oh, well.

Erik

[erikjgreen]

Hmm, not a lot happening. Here's a summary:

I received my dugong2 drives from cnc4pc. Arrived as expected, except the sticker on the front said "for use above 80 volts, use the braking circuit". When I bought 'em, Arturo said that for high performance use above 100 volts, I'd need the brakes. I skipped buying them because I was only at 100, and I didn't want to spend more money if I could avoid it.

After emailing him back, I got info from Balasz too, and decided to avoid any potential difficulties and order the braking circuits too. So, I'm covered now.

I need to order a new Mesa card this week too... I could make the old ones work just fine, but I figured that it'd be easier not to. I'm going to get a 7i43S (if I got the number right) which is a multi-axis motion oriented RS422 card with one analog output for a spindle. I'll replace my 4 axis servo card with that and generate stepgen signals for the dugongs with it. I may use a stepgen or the analog for my WJ200 vfd, haven't decided which yet.

I also haven't figured out what to do with the encoders. The dugongs have inputs for differential encoders, which I have, but I'd actually rather close the loop in linux-cnc rather than the amps. I don't think I can use the amp tuning software if I do that, however. I'll have to see if I can get some kind of virtual encoder set up in linuxcnc.

In other news I picked up a really nice 5kva transformer for $35, so if I want to go to 160 volt servos I can. Dunno what type or brand of brushed servos operate at that voltage, but if I find 'em I can run 'em. For now I'm just going to use the existing servos at 120 volts (up from 100 with the old amps).

I got a control pad ordered for my surplus VFD, so I'll see if that works. If it doesn't, I can always pull parts out or fix it... surprisingly few parts in it anyway.

I've been spending time pulling apart some equipment I bought to get parts out of it for another project, so nothing done on the mill this weekend. Too many projects.... but I wouldn't have it any other way.

Erik

[will gilmore]

i´m interested in your VFD repair. i smoked one awhile back by wiring it incorrectly. oops.

[erikjgreen]

I feel your pain.

Right now I'm hoping I don't have to repair two. I made a mistake with a grinder yesterday that caused my brand new Hitachi VFD to fall to the floor.. I think damage was limited to the plastic case, but we'll see.

I'll update this thread soon. I just got things in the shop cleaned up after disassembling some equipment for parts so I can now re-do the mill electronics. I have three new Dugong drives with brakes ready to go in, but I've got to re-layout all the parts so everything fits, plus I cut off the old monitor arm from the dynapath and I'm hanging a second cabinet on the other side of the mill for the spindle drive.

More soon.

Erik

[erikjgreen]

Time for another quick update.

I have been working on getting the second cabinet (for the spindle drive) cleaned up and finding a way to mount it. I may have to weld up a bracket or two for that.

I also cleaned out my other electronics layout to prep for installing the new servo drives and also possibly replacing the computer... I got another cheap computer with a smaller motherboard that'll fit there and save space. Same speed and memory.

I bought capacitors for the DC supply I'm putting together for the drives... 10 amps per servo drive (continuous) x3 is 30 amps, at a rule of thumb of 2000uf per amp, that's 60,000 uf or about 13 beer can size 450v capacitors. I'm going to attach them in a double line down one side of the cabinet, not sure on mounting method yet. Then I'll put a plexiglass cover over their terminals for a shield.

I'm sizing the electricals so I can either tweak the servo voltage to 130 volts or so for better performance (per Al the man this is normal practice) or replace the servos and go up to 160 volts.

Once the caps are mounted I'll install the servo amps and brakes, then the PC and I/O boards. After that I'm hoping to have the spindle drive cabinet mounted so I can run a section of 6 gauge SJOOW across to it and put the Hitachi inverter in.

I've salvaged two AC line reactors from a pair of old VFD driven pump controllers. I don't know exact ratings on them except that they're labeled "25Amp" which is less than the rated amps for my drive... but there must be a difference in labeling between the drive and these things, because the drives they came off of were 15hp units?

Hmm... just had a thought, maybe it's because they were three phase drives.

If I can use these, then I'll put one in as a line reactor, and one as a load reactor. If I can't use one for line, the other should still work for load.

I'm also planning on putting contactors for stuff like the coolant pump in the spindle cabinet.

Onward and upward.

Erik

[samco]

TI 99/4a Alpiner?

Onward and upward.

Erik

[erikjgreen]

Heh... I don't actually remember when/where I learned that expression, but I've never owned a TI99/4A or played Alpiner. I was using Apple IIs back when that came out.

[erikjgreen]

I spent the weekend fiddling with capacitors. Tried 3 different ways to mount them, they all take up too much space.

Plus for the most part they didn't look very good. I don't have enough of the 3 inch metal brackets to mount the things vertically, so I tried making a mount out of plywood with some plastic tubing the right size glued to it. Worked ok and held the caps fine, but it took up a third of the cabinet.

I may use a separate box.

Erik

[erikjgreen]

Phew. Well, I couldn't find a good way to mount the caps to the backing board in my cabinet, so I ended up just lining them up at one end of the bottom.

I'll try to make a simple lexan cover for them, so nothing can fall on them and short them out. It should also hold them in place pretty well.

I figured out I can't use the smaller computer I wanted to put in, there's no support for the PCI cards except the slot connectors if I use it, and there's only one PCI slot in it, which limits things a bit. I decided to re-mount the other one I already had working a bit higher up for better clearance.

Since I decided to put the spindle drive in another cabinet (which I have yet to figure out how to mount to the other side of the mill) I should be ok on space, although a bit crowded. I have to put a 24 volt power supply, some barrier strips, a couple relays, three servo drives and brakes, and wiring into the first cabinet. The spindle cabinet will have the VFD, contactors for coolant and air, line reactors, and some misc other things.

Erik

[erikjgreen]

Here's a crappy diagram of the layout, mostly posted for my own reference

[erikjgreen]

I got a nice big aluminum heat sink at my local surplus place last night.

I'm going to change the diagram above so the amps go where the brakes are, mounted on the heat sink, which will itself be mounted on edge to the back board of the enclosure.

It'll be a bit harder to get to the screws on the end of the servo amps mounted near the back board, so I'll break those out with jumpers to a barrier strip nearby and label them.

The brake circuits will be mounted just to the left of that, with the backing board as their heat sink. Plenty of space to get to all the screw terminals involved.

I spent last night drilling and tapping 12 holes for mounting the amps, and picked up some heat transfer paste today. I'll get some L or shelf brackets to mount the heat sink in place tonight, and hopefully get the amps and brakes mounted. Then it's on to wiring.

Pics soon.

Erik

[jsantos]

Wow! This is a real blessing. I just got myself a Lagun 250-s and was trolling the net for info on converting the electronics for it and saw your thread.

As as luck would have it, it looks like you're in the Minneapolis-St. Paul area as I am!

Got a couple of questions:
1. Which Hitachi VFD did you get?
2. Which surplus store do you go to?

Watching your progress with keen interest.

Thanks!

[erikjgreen]

Wow! This is a real blessing. I just got myself a Lagun 250-s and was trolling the net for info on converting the electronics for it and saw your thread.

As as luck would have it, it looks like you're in the Minneapolis-St. Paul area as I am!

Got a couple of questions:
1. Which Hitachi VFD did you get?
2. Which surplus store do you go to?

Watching your progress with keen interest.

Thanks!

Thanks I've been slacking lately, getting a big air compressor and lab oven working and getting my TIG setup repaired and going again.

I bought a Hitachi WJ200 VFD from drives warehouse. I got the model for the 7.5HP amp level per Hitachi's derating document (you size the drive based on the FLA of the motor multiplied by a factor for single phase - I recommend downloading the doc).

What size is your motor? What controller? New milling machine or old one?

As to the surplus place, there are a pile of 'em I go to, including Ax-man. What sort of stuff are you looking for?

Erik

[jsantos]

The machine got delivered today. Unfortunately, they had to take the motor off to get it into my garage but then we couldn't get it back on. The guy who sold it to me kindly offer to come and put it back on for me.

The machine was built in 1997 but it's in great condition. We were playing around with it right before they moved it and everything is in great shape - spindle, servos, everything.

The motor is a 5HP. I've never such a humongous 5HP spindle. I've got a 5HP colombo spindle and it's not even a third the size of the spindle on this machine.

The manual I got says I either have the Dynapath 10 or 20. This one has an rs-232 connection and from what I remember reading, the -10 does not have an rs-232, so I'm assuming that this is a -20.

Since I'm a newbie at this (meaning absolutely zero experience), I'm looking primarily for tooling. The only tool I have is the vise that the guy gave me with the machine.

Where are you in Minneapolis? I'm in Apple Valley.

Are you still looking for manuals? I've got 3 manuals that came with the machine.

[erikjgreen]

Cool... I would love to see a manual with details on the oiling mechanisms and some other tidbits.

Yep, it's a big, beefy machine... mine has a 5 hp motor that is about the size of a modern 15.

I'm guessing yours has the same spindle setup as mine, a 40 taper. Exactly which 40 taper is going to depend on whether the drawbar has been replaced. The default is for NMTB40, which is tapered for tool set repeatability but does not have an auto tool loader stud.

The machine can, with a drawbar replacement (pretty simple, some people switch between drawbars daily or per job) use BT40 or CAT40 tooling.. in either case it's just an adjustment to the length of the drawbar and/or a thread switch.

I recommend you not pursue NMTB40 tooling, but rather go for CAT40 or as a second choice BT40... they're cheaper and more common, I've found. If you want to buy new, I recommend Glacern machine tools as a good source.

Myself, I have bought tool holders where I found them... local auctions, surplus stores like Global, or Ebay sometimes.

Having a vise is good, that'll make certain things a lot quicker. I bought a "super spacer" rotary table for mine that I'm going to CNC as soon as the rest of the mill is working.

I happened to luck into a lot of indexable tooling myself, but you can probably do ok with a selection of medium size carbide end mills (3/8" up to 1 inch are the workhorse sizes generally). What sort of milling will you be doing, in what materials?

FYI, there's a machine shop liquidation going on up on the north side, you see the guy posting on craigslist a lot. He wants medium level prices, but he has a good selection of tool holders of various types. He knows well what they're worth, though.

Be aware you may want to change the coolant system around... by default it has a drain in the skirt of the mill in front and the reservoir under that tends to be very dirty and full of chips in older mills. Plus, it has by default a three phase pump motor that sprays mist coolant from the flexible neck on the head. I'm replacing mine with a kool mist 77 setup using a waterfall pump supplying loc-line fittings for flood coolant.

My control was a dynapath delta 10 originally... it did have an RS-232 port, so yours might be a 10 too. It should say on the front of the control pendant (the box with the monitor).

Post some pics of your mill, I'd like to see the condition and maybe I could tell you a couple things about it.

It's also possible we could visit each other at some point, like if one of us gets stuck getting the mills working properly. I'm in Brooklyn Park.

Cheers,
Erik

[jsantos]

The manuals seem complete and a quick look tells me I've got the mechanical and electrical drawings and parts list. So you're welcome to them.

They already replaced mine to a CAT40 and the guy made a point of telling me that I should not go back. :-)

I also got a mister for it but I don't know exactly what it is.

On the control pendant, it says dynapath 1000-32. So I don't know what that is.

I'll post pics tomorrow.

I would love to visit one of these days. I'd like to make it this month yet if possible as I'll be out of the country for most of June.

[erikjgreen]

No hurry, I expect I'm busy for most of June too.

From the docs I have access to, it looks like the 1000-32 CNC control might be a Lagunmatic rebranded Dynapath Delta 40... do a search for that and see if the pictures look familiar.

On the manuals... cool. If we can arrange it sometime I'd love to scan selected pages.

I'm interested to see the mill itself, since reading the specs it looks like it has a different weight and slightly different capabilities from my 250.

Erik