[erikjgreen]

Hi, all;

I'm about to start cleaning up, testing, and then updating a Lagunmatic CNC 250, a 3 axis CNC knee mill I bought almost a year ago at an auction.

It's currently got a Delta Dynapath 10 controller, a 5 HP spindle motor, and the original electronics in a side cabinet. I don't have a pic yet of my own mill (I just finished moving it into my shop space) but here's a generic pic of the same model, to give you an idea:



I've almost gotten my phase converter assembled, and once that's done I'll be able to power the mill up and test it.

Longer term if the servos and drives are good, I'm going to replace the rest of the electronics (everything but the drives and power supply parts) and run the machine with emc2 and a VFD on the spindle. I want to be able to run some rather large programs on it as well as add a 4th axis later.

I do have a few questions at this point:

1) Is there anything I should be aware of as far as "gotchas" for starting this thing up the first time? I'd hate to miss something that caused damage. At this point I'm planning on making sure there's lube getting to the ways and spindle, then trying manual moves of the table, then spinning up the spindle under power.

2) It looks like I have an auto-lube system for the ways and spindle (2 Bijur lube systems) both have oil that looks good. Should I do anything to recommission these? Add more oil? Test?

3) Mostly at this point the mill needs clean up and a bit of de-rusting.. there's no serious rust on most of it, just one spot on the table where there might be a little pitting. I was going to clean the rust with naval jelly, sand with 320 grit, wipe with xylene, then a thin coat of grease or way oil. Should I avoid this method for the surface rust on the Z dovetail? The other parts of the ways just have grease and dirt on them, but the Z has some rust. I have hard chromed ways, I think.

Thanks for any help you can offer, I'll get pics of my own setup up soon.

Erik

[LUCKY13]

This will make for a very nice setup when you get done. Its hard to beat the versatility and durability of one of these mills. The true is it doesnt take much more room fro a full size mill compaired to a bench top mill, the weight and being able ot get into most peoples hobbie shops is what holds most people back form going this route.


AS far as the cleanup, I would not use any sand paper or or such products on it in any way. Even scotch bright is not good. The naval jelly is good and just using something like the green scuff pads that are made for house hold cleaning ( not sctoch bright type). Brass wool also is good. The sand products and the scotch bright can leave bad stuff inbeaded in to the cast iron which willl be a bad thing in time. It may seem like you can clean after using such products like sand paper but cast iron is bad for having micro pores which can hold such particals and cause bad wear later on. Really the little soap filled grean pads like buy for cleaning pots and pans works great, and so does the BRASS wool. The brass wool is real good because it can kinda leave a polished look to the metal, plus its soft enough not to dig in and remove to much metal.

When I cleaned my mill up I did this with three in one oil and the green house hold pads. I soaked the oil on th ebad spots to let the rust soften and then it came right off. Soap and hot water after the scrubing, then oil it all up and it should be good to go.


If the machine has been sitting where it can draw moisture bearings can get rust spots in them. Not much you can do about if they have except replace them ( my spindle did this but it sit a long time after being brought over on a boat, so it had salty moisture). Just run anything you start up slow and give it time to show any heat if there are problems to start up. Rough sound, and heat will be your indicator of any such problems. Running slow speeds at first might save you from a total lockup if anything like this is going on . Using a infra red temp gun can help monitor things like the spindle when you first start it up.


Remember to check the drive screws for rust and oil also. It might be a pain to do so but a total tear down might be best of the table and saddle. Its something you will have to do in time anyway if goign CNC and you will get to know your mill better this way, and maybe again save damaging something that just needs cleaned to last instead of grinding it to death because of unknown hidden rust/dirt.

The old oil should be removed because it will be bad for drawing moisture. Unhooking all the lines at the last point and flushing the system will be will worth the effort. The oil pump if it has drawn moisture and gained rust should be torn down and honed. This could save it from damage also and these things are not cheap. Chances are it is fine, but if it has rusted any as soon as you pump it the seals will destroy abd any rust will be mashed against needed seal surfaces. A tear down could save it.


I know it all sounds like a lot of work, but you need to know how all these system are designed and built anyway. And the money saved, and performance gained will be worth it.

These are nice mills and I wish I had the room and resources to get one myself. Keep us posted on your work and cleanup.

Also be very carefull with your electrical, there is a lot of power goin here. Big capasitors can still be holding lots of joice that will be no fun to get unload with ( can even kill you).


Think about everything your doing, take your time. This big stuff is nothing ot be getting in a hurry with.

Jess

[Southbend Sam]

When you wire the phase converter to the control you need to use care. Two of the legs of the 3 phase input power go to a transformer which converts the 220 volt input to 110 volt single phase to power the Dynapath control. You need to ensure the generated leg does not connect to this transformer. You can also get good information on the Dynapath control by perusing the Tree milling machine threads (most Tree's use a Dynapath control) as well as the Dynapath threads.

[erikjgreen]

Sam and Lucky, thanks!

The phase converter circuit I'm using is a pony start with capacitors to balance the three phases... it's supposed to be specifically for CNC machines, which are picky about that... is this what you describe?

It's the one here:
Phase converter for cnc

It sounds like I should do at least a partial tear-down and cleanup before I do anything to try running it. I'm rigging up a chain fall supported by 4x4s so I can re-mount the head, I suppose I'll leave that in place so I can lift the table and other parts.

I ordered Mobil way oil, spindle oil, and some Kool Mist coolant from McMaster-carr yesterday, so I'll plan on draining the oil from the Bijur units and replacing it. I'll also restrict my naval jelly use to non way surfaces. There's really not that much rust anyway. The table top has the worst of it, and it was already damaged from a tool bit crash... I was planning on having/making a tooling plate for it anyway.

The drive ballscrews have almost no rust or other problems.. I think because of the type of metal they are? They look nice.

Looks like this weekend I'll have time for scrubby pads, simple green, and elbow grease. Pics after that.

Erik

[Southbend Sam]

The phase converter I use is similar to yours. The thing about the Dynapath control (unlike some other cnc controls) is that it only uses the 3-phase to power the spindle motor and the rest of the control and servos are powered by by the single phase power split off from the input 3-phase. If your phase converter is well balanced it might not matter where you route the generated leg but it is a simple matter to wire the control as previously stated and I would recommend you not wire the generated leg to the control power transformer. By the way, if you review some other posts, you will see how to set up an rs-232 connection to a PC and download programs. If you have the ability to dripfeed (it was an option Dynapath 10's) you can actually run rather large programs. You're out of luck for the 4th axisthough probably. Hopefully, you have the Dynapath manual.

[erikjgreen]

Actually I have some maintenance docs for the Dynapath, not much else.

My controller seems to have a drip feed option, it has an RS-232 and also cassette ports on the control box.

I don't know if drip feed is as good performance wise as a better controller, though?

I do want to eventually build either a spindle based 4th axis or maybe even a trunnion table set-up for this mill.

Erik

[erikjgreen]

I made out like a bandit at a local surplus place yesterday... picked up a couple 1 inch cobalt steel end mills, one four and one six flute, plus an indexable 3/4" end mill with 20 inserts, a slitting saw blade, and a couple solid carbide end mills, 3/8" and 1/4", for $40. All brand new.

Anyone in the Minneapolis/St. Paul area that wants to know where give me a PM. They're surplusing a machine shop's tooling, and they have a big pile of cat50 stuff, drills, mills, and three boxes of dinged/broken stuff too. Also a bridgeport and two nice surface grinders.

I'm going to stop back today and see if I can pick up a ball screw.. I almost have enough parts to convert my mini-lathe too

Erik


PS: Forgot to mention - I'm having a heck of a time finding somewhere to get the wire for my phase converter. I need 4 gauge THHN, and my choices seem to be get it for $2.50 a foot in black only at home depot, or else order from Mcmaster-carr at $43 a segment for 20 feet (I need about 80 feet total for 1 phase 240 inbound and 3 phase generated). Any pointers to better sources would be welcome.

[erikjgreen]

Well, I spent more time than I wanted to this last weekend getting a light gantry crane built over the mill so I could reassemble it. For storage, I had removed the head and lowered it onto the table. That worked ok as far as shortening the mill.

It was so hot out I didn't do a whole lot over the weekend, even indoors.

I'm repeatedly kicking myself for storing this thing in my other garage over last winter... I didn't have a choice, but I'm sure the rust on it is all my fault. Oh, well, I guess I'll have to deal with it.

The mill is currently in its final location, but on wood blocks. Tonight I'll lower it to the cement and level it with sheet metal shims.

Here's some pics of the mill. Sorry for the sideways images... I rotated them in photobucket and it shows them right side up, but not when I link to 'em.



Here it is with the head on... took way too much effort to get it aligned and mounted, but I did get it back in place, with the shim back where I found it. There was a patch of rust on the hand scraped surfaces where the head mates to the column, and by the time I discovered it I wasn't equipped to clean it, so I just made sure the shim wouldn't overlap it.




The Y ways look mostly ok.. they were under the rubber sheet way cover, probably protected them from some water.



The Z ways for the knee have some rust.. the knee is manually adjustable, although I could power it later... not sure if there's a reason to do so. You can see the back section of the Y left side ways here too.




The X ways for the table have some rust on the exposed dovetail surfaces... nothing too dramatically deep, but enough to be concerned about.



On the good side, the ballscrews look good, at least the parts I can see. I was surprised to not see linear encoders like I've heard about on this thing... according to the motor label it has "tach output" for the servos. Is this a rotary encoder or resolver?






Limit switches on the table bottom... looks like they're adjustable.





The worst rust is on the table top. The wheels are I think hand wheels I can attach if I remove the covers from certain locations, mostly the end of the ballscrews I think?




I got a few tools with it... it's an NMTB40 taper, I have a replacement drawbar that should be CAT40 I think. I have a vise too, with no jaws (not pictured)




Bijur lube systems, looks like it auto-lubes the spindle and ways. Can I replace the clear tubing for this with polyethylene tubing, or is it something special?



Spindle itself looks ok. There's some rust on the dovetail for the "neck" which apparently can adjust through 180 degrees or so on the column, and extend out 20 inches or so.

I used the back gear lever to put the spindle in "neutral" and gave it a spin by hand... turned easily, almost no noise, so I'm thinking that's good.



The knee is currently all the way down. I think the little black arms are gib locks to hold the various axes in place? I made sure they were loose, then moved the knee up and down a bit.



Electronics box. Looks ok, nice and clean. I'm going to try to run up the mill on a phase converter with the Dynapath controller and see if it works before I start messing with upgrading it.





Pneumatic valve for controlling the power drawbar. Handle got bent during the move of the mill, I'll have to replace it.




My next move is to scrub all ways that have rust with a scotch-brite dish pad to smooth them, and apply a little way oil. I'll use naval jelly to remove the rust on the table and anywhere else it's not on a datum surface.

I'll also start using simple green to clean and degrease the whole mill, and I'm going to try to get access to the sump in the base to clean it out. Right now there's a lot of oil in there from drip-down in storage. After I saw it starting to rust I went a bit overboard to try to preserve it.

I'm also working on a phase converter and wiring to power this thing up... got all the parts except the wire, just need to get it all together.

Erik

[erikjgreen]

I got some cleanup done with citrus degreaser and brillo pads. Took off most of the rust pretty easily, so I'm confident it's not a real problem.

This weekend I'm going to unbundle the lube system lines from the tubes on the machine sides and clean/replace them. Only one is disconnected, so it should be easy to get to a point where they're all clean and ready for use. Then I need to clean/flush the Bijur lube units and re-fill with oil.

After that I should be able to try moving the table around a bit with the manual crank handles (I assume, anyway... I haven't pulled the covers off the spots where they're supposed to go).

I might be able to get the wire I need for the power hookup soon, the stuff is so darned expensive to get anywhere local so I'm going to have to go with McMaster Carr, I guess. $43 for a 20 foot length of 4 gauge :\

Erik

[ebrewste]

I was surprised to not see linear encoders like I've heard about on this thing... according to the motor label it has "tach output" for the servos. Is this a rotary encoder or resolver?
Erik

I can't see enough info about the feedback to tell, but can give you some rules of thumb.

In that era, tachs, plus another feedback (encoder or resolver) were common. There were some good (and not so good) reasons to use tachs then. The tach can not realistically do all the feedback by itself, so there needs to be another feedback (encoder or resolver), whether is is linear or rotary. It would be strange to see a rotary encoder in a motor that already has a tach in it, but stranger things have happened. Maybe you have trav-a-dials for linear encoders? They don't look like regular, long, skinny linear encoders.

Assuming you have the schematics / manuals, look for the encoder input connectors on the controller. Is anything plugged into those? Maybe they got liberated before you got the mill?

As for having encoders in the motor: how many wires are coming out of the motor?
- 2 heavy wires for a dc brush motor power
- 6 small wires for a resolver
- 6-8 small wires for an encoder
- two small wires for a tach

Good luck on this one. I have an FTV-1 (your, but manual), with a re-CNC retrofit. They seem pretty similar, though they don't share any electronics.

You might want to share some better pictures of under that lagunmatic sheet metal on the table. There might be something helpful under there.

Erik

[erikjgreen]

I'll see if I can get a better pic.

From what I can find on the motor specs, they include both a tach and an encoder, which may have a 500 or 1000 line resolution. The wires from the motor are in three multi-conductor cables.. one seems obviously to be power, a small one that could be tach, and a medium sized one that might be encoder.

The encoder inputs on the drives (what I think are the encoder inputs) have wires in them.

I didn't get a ton done this weekend, mostly I'm still cleaning up the mill. I also picked up supplies for flushing out the bijur lube tubes and repairing/reattaching the one loose tube. My next step on the mill is to get the lube system working and flushed, after which I should be able to try manual moves of the table.

I also got some conduit in place for the phase converter this weekend. I still need to pick up a cutoff switch (can I use an AC cutoff for this?) and a three phase main breaker to distribute the power. I did find I can use the 4 gauge wire from the local home depot, I just need to use colored tape to identify the purpose of each wire. Much cheaper than McMaster-carr.

Erik

[ebrewste]

I'll see if I can get a better pic.

From what I can find on the motor specs, they include both a tach and an encoder, which may have a 500 or 1000 line resolution. The wires from the motor are in three multi-conductor cables.. one seems obviously to be power, a small one that could be tach, and a medium sized one that might be encoder.

The encoder inputs on the drives (what I think are the encoder inputs) have wires in them.

That sounds like the only encoders you will have. A mill from that vintage is unlikely to have triple feedback (tach + rotary encoder + linear encoder), though I suppose it is not completely impossible. Let's guess that you have 0.2 pitch ball screws and 1000 line (4000 count after quadrature) / rev encoders. That is 0.2 / 4000 = 50 millions inch resolution. That is completely workable, especially with tachs.

If you really had your heart set on it, you could go to linear encoders with the tachs, but you would need to figure out how to configure your controller to deal with the new resolution. It may or may not be a big deal. You also will need some sort of interpolation device to get a quadrature interface with that resolution. All doable, but not trivial.

From my experience with my ftv-1, I would spend some time making sure your ball screws and support bearings are backlash free. Mine have about 0.001" - 0.002" backlash, depending on the screw. It's a major limitation on performance.

It sounds like you are doing good work with all the lubrication, etc. It's a good investment in time.

All the best,
Erik

[erikjgreen]

I've been working on and off this week on getting the lube system done. When the weather is good, I'm outside trying to finish another project.

I also stopped by a local re-use center and got a couple of swivel chairs and shelves for my shop.

This weekend I'm hoping to finish wiring the phase converter... I have to buy a breaker panel and the 4 gauge wire and get it run plus wire up all the capacitors and mount the control box.

If I can get that done and get the lube system working, then I can have my electrician check my work and try starting up the mill.

Erik

[caracadon]

What happened to all the images?

[erikjgreen]

What happened to all the images?

My image hosting is down. I'll check to see if I can find somewhere to put the images and restore them from a backup.

FYI, I'm currently getting ready to build another revision to my mill, a new control panel.

Erik

[mungaro]

Eric

Hi, all;

I'm about to start cleaning up, testing, and then updating a Lagunmatic CNC 250, a 3 axis CNC knee mill I bought almost a year ago at an auction.

It's currently got a Delta Dynapath 10 controller, a 5 HP spindle motor, and the original electronics in a side cabinet. I don't have a pic yet of my own mill (I just finished moving it into my shop space) but here's a generic pic of the same model, to give you an idea:



I've almost gotten my phase converter assembled, and once that's done I'll be able to power the mill up and test it.

Longer term if the servos and drives are good, I'm going to replace the rest of the electronics (everything but the drives and power supply parts) and run the machine with emc2 and a VFD on the spindle. I want to be able to run some rather large programs on it as well as add a 4th axis later.

I do have a few questions at this point:

1) Is there anything I should be aware of as far as "gotchas" for starting this thing up the first time? I'd hate to miss something that caused damage. At this point I'm planning on making sure there's lube getting to the ways and spindle, then trying manual moves of the table, then spinning up the spindle under power.

2) It looks like I have an auto-lube system for the ways and spindle (2 Bijur lube systems) both have oil that looks good. Should I do anything to recommission these? Add more oil? Test?

3) Mostly at this point the mill needs clean up and a bit of de-rusting.. there's no serious rust on most of it, just one spot on the table where there might be a little pitting. I was going to clean the rust with naval jelly, sand with 320 grit, wipe with xylene, then a thin coat of grease or way oil. Should I avoid this method for the surface rust on the Z dovetail? The other parts of the ways just have grease and dirt on them, but the Z has some rust. I have hard chromed ways, I think.

Thanks for any help you can offer, I'll get pics of my own setup up soon.

Erik

Eric:

I have a the same machine with all the books and manuals. When you start it up make sure that everything is in the off position. The machine needs to be zeroed first or it will not take off and work.
mark

[mungaro]

Eric:

What are you going to do with the old controller? I have the book and manuals for the machine.

Mark

[erikjgreen]

The old controller (dynapath delta 10) is sitting on a shelf. It and the old keyboard/monitor arm are going to be sold for whatever I can get, I guess.

If you're willing to scan in the wiring diagram for the machine, plus maybe the manual that shows how to do service on the ways/lube system and the head, and the coolant system, I'd be willing to trade

The dynapath controller worked ok, it's just that it was slow and only held a limited number of program lines. So I decided I'd rather run the machine with EMC.

I'm also upgrading to a VFD for the spindle which is almost a spindle servo controller. With a few limitations, this should give me more or less equal functionality to the Lagunmatic 310, which had a spindle servo and drive for tapping etc.

Erik

[erikjgreen]

Also, over the weekend I tried one config for the limit switches, it didn't work as well as I wanted (translation: I made a major mistake in wiring and got nowhere).

On the bright side, all the limit and home switch wires are identified and labeled, and trimmed to the right size for routing in the cabinet.

Tried to get my 24v power supply working, found out a fuse is blown on it. Planned out SSRs and contactors for controlling power to the VFD, coolant pump, air line (for chip clearance) work light, etc.

I'm running out of cabinet room, so I'm being careful placing items.

I think I'm going to upgrade to EMC2 beta 2.5, since it has some features I want, including the touchscreen interface.

Erik

[mungaro]

Eric:

I will have the books completly copied and bound for a complete trade of what you have that you are not going ot use on the Mill. I am not very savy on change outs but I would shure like to change mine out also. I did a change on a CNC lathe to Mach3 Turn and it was a pain in the rear and dread doing it again. Thst is the reason for trying to keep my machine in spare parts.

Mark