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Contest for the most insane member (They will be a Maho owner)

I always wondered about that tool changer design on my DMU50V, as the tools drop straight down into the pockets. Not much clearance on some tools. Was the upper shoulder above the taper on the emuge toolholder larger than the hole in the tool changer disc?

I bet you could sell a few of these to folks with the older DMU50's, especially in europe.
Thanks for your feedback Mark (2x)

I'll explain why the Uberchuck damages the carousel in my next post.

The alignment procedure of the magazines as well as the spindle is a much longer process to do properly than I had thought, but worth it as now the entire sequence is pretty much silent. It required making an excel sheet to create average values for things like spindle orientation and retract values both of which are single machine constants but the machine has two carousels (This isn't noted in the procedure they recommend). Most of the other constants are carousel-specific. What makes adjusting the DMU tricky is the simple fact that if anything is slightly out the machine will use MAX FORCE when it moves and damage everything it can. Many machines use alternative motion devices, like air cylinders and proximity sensors for the ATC loading and unloading which makes misalignments pretty non-destructive. This is not the case with the DMU, MAX FORCE everywhere. Add to this the many steps it requires to start an ATC process, stop mid way, cancel the operation, change the switches the cabinet to still allow movement, override limits, etc etc just to get the machine to move in the ATC zone. If you do a spindle orientation (which you must without de-energizing the servos before confirming drive key alignment otherwise the spindle will simply turn out of alignment) and you are at the wrong Z point you will wipe out the proximity sensors on the carousels.... I didn't have it happen but it would be very easy to do! You need to do this AFTER having your first coffee of the day.

Here is a photo of two stubby ER32 holders being used to find the center of each carousel pocket when in position.


There isn't much vertical space to work with, the spindle is already at max height in the photo.

As for making more of these, I would open to that after I'm done getting caught up on machining work that has been delayed from this latest move/paint/maintenance/repair episode that took much longer than I thought it was going to. Please PM me if interested, the greater visbility and clarity of the pocket number alone is worth it, I really disliked the OEM engraving.

Getting the ATC setup on Maho Sr. will be easy now, I already translated the entire document that shows the procedure and it has better access than the 50V does, and it only has one place the spindle needs to be. Much of the adjustment on the MC800H is mechanical with the ATC arm (hydraulic cylinder actuated, which is clearly seen in photos I took when going through it a while ago), only the spindle position, orientation and magazine chain position are machine constant controlled.

Both the DMU50 and MC800H were way out of proper adjustment, this is obvious by the markings on the MC800H and simply the sound of the DMU50V doing a tool change before.

Here is a tip for anyone thinking of tackling the ATC on the DMU50V or 70V: Check the spindle concentricity values with the carousels while you still have the ATC covers off. That will save a lot of time.
In regards to the Albrecht/Emuge APC/Uberchuck tool:


If the tool looked like the tool in this first drawing it would be fine. They obviously have come up with an updated profile to allow for the necessary clearance for certain tool changers. Not all Cat40 machines will be affected by the original profile which is a better design if you can use it.


As highlighted, D3 is 50mm in diameter while...


Cat 40 typical standard is 44.45mm (1.75"). That extra 5.5mm will break your cast iron carousel if you have a 24 tool DMU50V or DMU70V: It makes a loud noise in the process and will likely break the alignment spring pins too, as well as misalign your ATC with your spindle.


My new carousels work great though while still preventing the tool from being inserted manually 180 degrees out in regards to the drive keys. More on Maho Sr to follow...
Just a small update on the MC800H:

The pallet changer tapered pin gripper unit actuator pins, or at least that's what I'm calling them, are now being remade. I had some Thomson 60 case ground shafting brought in just for them as the OEM pins were worn, one was actually severely damaged...


Like the metallic looking paste where it rides on needle bearings? Me too.

Also, the APC area doors are back, most of the paneling and doors are already coated I'm just taking small loads from the coating facility so I can ensure the paint will not get any scuffs or scratches in transport:


(It was raining when they were brought in so I was just wiping them down with the towel on the one door)

As with the Mori SL-6B and Maho Jr. the doors are white on inside to increase visibility and dark grey on the outside. I can confirm with Maho Jr. that the white on the inside really makes a big difference for brightness!

The plastic letters that go on the doors are actually not in too bad of shape and I'll repair them and paint them to put them back on. I think if done properly they will look quite sharp! I think this is the last year they used such lettering on the machine as the later machines just used decals (Probably to save cost).
Thanks for your feedback Aaron,

Yeah having it all recoated by taking it apart takes much longer but the end result looks so nice and gives you the chance to catch all the little things that might be a current or future cause for problems once the machine is going again. I've caught enough problems on every machine I've done this to that I have no regrets taking the extra time, if anything now I can't do it any other way for fear there may be something hidden!

Maybe it's better to say "The machine needs to be completely dismantled for maintenance and since I've gone to the effort anyway I get it recoated while I do it". The main purpose is function first, the coating is just a bonus since I'm doing so much work anyway.

Also, just to clarify, this coating is Endura polyurethane which isn't technically powder coating but is a two-part sprayed-on-like-paint opposed to electrostatically applied and baked on like powder coating. I just want to make sure everyone knows in the event someone decides to do what I'm doing. It isn't cheap, it is actually very expensive but having done it myself before I have no problems paying someone else to do it and to pay such a price. It is a very good investment in my opinion.

Here are some even closer up shots of that pin now that I've wiped it off:



The wear is so bad, to have caught this problem when so many others had gone through this machine is a relief. The only way parts like this get caught is when assemblies are fully torn down solely for maintenance, like a power chuck or something. I have no doubt the pallet changer still worked and there would be no way to know this ticking time bomb was going to cause huge damage shortly. If that pin were to get worn too far that particular tapered lug of the pallet wouldn't release but the machine would think it did because it bases that feedback off the main hydraulic cylinder that pushes a ramped plate against these pins. Thankfully that plate isn't damaged and the wear is limited to these pins and the needle bearings they ride in, all of which are being replaced.

...actually I'll just make a correction...

I just took a close look at the pallet changer base. It has damage on it and I thought it was from a previous crash... it isn't. The damage is from that pin not letting the pallet go on that lug. Because that lug wouldn't come out it managed to pull the one opposite of it furthest away from the lifting mechanism and levered the pin against the casting, breaking away a large chunk on that boss while breaking a little material away on the hole that was held down. DMG has already said they don't think the damage will affect the machine much but I'm going to have to spend some time figuring out exactly what can be done to make sure everything is in alignment again, and held as firmly as orginally intended. If I could get a replacement for that large cast part I would but the only way I can get one is off another MC600 or MC800 that is being parted out, though it is shared with the 4 axis machines so it is much more common relatively than the trunnion MC800H. It probably isn't necessary though, it is good to know why that damage happened... it is obvious from the markings this is exactly what occurred.
When I tear the sheetmetal off a machine I send it in all it's greasy chip covered glory to a cheap blaster/powdercoater. The last machine I did was a fullsize pickup bed plus an 8x20 deck trailer filled with the nasty enclosure and doors. They did it all for $600 in white and dark gray. Only thing I did was pound some big dents out and weld up all the cracks in the doors. Very worth it for me.
...I send it in all it's greasy chip covered glory to a cheap blaster/powdercoater.

Totally, this is the other major benefit is the cleaning aspect it. Even if you did want to spend the time trying to get it clean the paint is in such poor shape it wouldn't look great despite being clean. Doing it this way serves many functions.

I can't believe the price you are getting your work done for, granted my work is done in Canadian dollars which are worth much less than American these days but even still that is a fraction of what I'm paying. I have been taking quite a bit of metal to them though and some of it is small parts that I know from when I did it take a long time to put clean and hang up to spray, etc etc.

It would be interesting to compare the area to cost ratio of what your getting done to the guys doing mine, I have a feeling your still getting a better deal. I'm not sure which handles heat better powdercoating or urethane... time will tell on mine to see how it holds up. What I have now is much better than OEM, that much I've already been able to determine.

Lastly I pretty much did the same thing taking out dents and everything prior to sending it over. Sometimes I had to get creative with large aluminum plates and old railroad ties as vertical "battering rams" to get dents to go flat without leaving any evidence of the event. It worked out much better than I expected! I was having problems with the sandblasters warping the sheet metal at first but thankfully that seems to be a thing of the past.

Today I'm milling some stainless parts and doing a grand prix engine swap for a client so no time to work on the machines, but more will come soon! Thanks Garwood for your post.

In addition to design and machining I have some slick 3D scanning equipment that really helps for these sort of projects!

I've used many powdercoaters and one of them has a "quote guy" that seems to base his prices off how much time you spend BSing him. They don't do great work, but for machine enclosures it is a reasonable option.

I try to do most of my products black oxide or type 3 ano, but when I need to powdercoat stuff that must look good up close I use a good shop just down the road from me and I sometimes feel I pay too much. I like the owner though and he sends machinework my way so it works out.

Keep up the good work. I hope it pays off in spades when you let her rip.
Hello again everyone. Well I've completed many more hours of research into the subject of the VME Based CNC control itself.

Here are some highlights:

The VMEbus itself has been quite standardized and has also been designed to be forward and backward compatibility to keep things easier for industrial and military applications where upgrading all of the system would be quite cost prohibitive, including software developed for such systems.

Some of the boards I've considered purchasing have support packages for DOS so the board will still have as much functionality as possible while being run via DOS.

Many of the boards no longer have RS422 and some don't have the ability to switch to RS485 either. In my case I need at least one RS422 port that can have it's address made to be the same as the original config so the "CNet" that is connected to the KIC modules that control the CNC panels still function. The EXM module that was used to accomplish this on the original setup has since been phased out and now there is a "PMC" type of port that such a board can be acquired to fill this purpose, theoretically.

I would like to talk more with anyone that reads this that has more experience with the industrial VME SBC units before I start spending quite a bit of money. I've read the thoughts that the improvements on the machine's real-world performance will likely be slim to none but we'll see.

Please post here or PM me if you have a moment to discuss some finer details on this subject.
I do have some experience with fixing the Millplus control. Right now I do have a 1996 DMU millplus with a controlproblem (Z50) which I thought it would be an easy fix but I was wrong. Used to have somebody with great knowledge of these controls but sadly he passed away. So now no support or knowledge anymore....Have to admid I am not a real computer-guru but I know how to fix machines. But if you lack info and / or software it might get an impossible repair.

My hat off if you succeed your plans.
Hello everyone, this will be a quick post. I decided for now to get some faster upgrade processors for now and keep with the existing CPU boards. This is the most for the least at this point and I'm told this gains about double in processor performance over stock (4x multiplier instead of 2x). I have come across some more machines that may have controls that would be great to retrofit on the Maho machines if more speed is needed, we'll see.

So for the last little while I've been putting a bunch of effort into cleaning and actually installing parts back on the machine. The progress is small but it is still progress.

First, I've been getting more parts back from paint. This is most the painted paneling:


And this is the ATC gearbox cleaned and mounted:

...and fail.

Ugh... for some reason I cannot upload more than one photo in this message on my laptop. The rest of this update will have to wait until I'm on the desktop.
Hello, do you have the manuals of the Mori SL6? if yes I need at least a picture of the tool turret positions logic or if you can tell me how it works, is it a binary code with 5 bits or?.
Thanks a lot!
Hi Marcos,

I haven't really looked closely at it but I think it works much like some of the tool changing carousels I've seen on mills. It has proximity switches and adjustable lugs on a ring that basically create a unique binary code like you say for each position.



I do not have manuals, I just kept my wiring ziptied together so I can put it back on as it was and clean it when there is no risk of mixing up sensors.

It's frustrating this forum has been giving me problems uploading photos otherwise I would keep providing updates on my projects. I'll try again soon.

Dave @ Nerv
Hello everyone!

Well I'm not sure how long it's been since my last post, but when I was casually looking for parts for my MC800H this thread came up so I figured I would post a short update.

When this thread began the MC800H was my first Deckel Maho, and my first from-factory full 5 axis mill. Since then I picked up a Dmu50V, which I went through and had all the paneling recoated, refreshed the spindle bearings, etc etc. That machine has been a really good money maker for me while the MC800H has been a really large space consumer. In the MC800H's defense I didn't finish it, but I'm getting close. The clamping units has been installed and the entire pallet changing station has been reattached. The chain was completely stripped with each roller cleaned and polished, the plates scrubbed, snap rings and bolts ultrasonically cleaned, and the whole chain reassembled and installed. That was a monumental task in terms of hours but it's done now and moves and bends very smoothly.

All that is left now is to reinstall the pallet receiver "rings" that locate the pallet into the carrier and start reinstalling all the servos, the Z axis ballscrew, belts and such. The servo drives still aren't totally finished with the recapping, it's been so long I worry the new caps have gone too long without any charge! I'll be following the siemens reforming trick and just run three incandescent light bulbs on the mains that lead into the power supply and use that as a means to slow the fill of the caps. I probably mentioned it but I sent almost all the paneling to this machine to get recoated, so all that will need install too. I'll need to get new windows made too, which will be costly these days with the increase of sheet prices due to Covid, but I'm saving that till last so who knows when that order will be placed.

I tore apart the rotoclear window to see how bad things were and it cleaned up well, many parts I ultrasonically cleaned to great success. Some plexus was all that was needed to bring the window back to near new clarity so that looks like it'll be able to be reused as-is, with only new bearings needed.

Anyway, the real reason I pushed so hard to get the chain installed and the pallet changing station installed wasn't actually to get the MC800H finished, it was actually to free up space in the shop. Once all those parts were mounted I was able to tear down almost all my storage racking and bring in two more new-to-me machines:

1. Another DMU50V, this one with the full production package including chip conveyor and 600L separate coolant tank with filtration.

2. A DMU50 eVolution, also with the production package, which on this machine is a 800L tank + chip conveyor.

After a bunch of work and maintenance I have the DMU50V operational, only just recently it melted a pin on the IGBT in the spindle drive and wiped out the pack. I'm waiting on new parts now to get that back up and running. The eVo needs a little love too, and I know once I'm on that I will not want to focus on the old DMU50V so I thought I would get that out of the way first. Also the 50V was much more familiar and easier to diagnose since it shares so many parts with my other DMU50V, though it doesn't have the optical DDC2 drives, which limits my ability to upgrade it's software to v400 (Which I did), but so far that software has been working great for what I need anyway. I upgraded the CPU on my other 50V and I may do it to this one too, since it also is 486 based, but I only purchased two processors when I bought the upgrades and I prefer to upgrade the MC800H instead. We'll see. The eVo has the newer LE based control that iTNC 530 machines have, so it's different entirely, other than it still uses Simodrive 611 drives with different controller cards. What I like about the control design is that it does away with the optical system the VME v400+ had, which is getting near impossible to get parts for, and the boards that are in the drives for communication with the control are very basic and bullet proof, with all the processing taking place in the control itself... just like the older version VME based contols. These details seem minor until the machine breaks down due to one of those boards (like my DDC2 optical DMU50V did), then it becomes very relevant very quickly!

At this point I'm not sure when the MC800H will be going, but hopefully soon. I do look forward to the chip clearing that will come from it's being a horizontal, and the machine's ability to clamp the trunnion and table so when I want to do aggressive roughing with a feedmill it doesn't make my shop sound like some sort of exorcism is taking place while killing my tooling in the process.

That's it for now! I'd upload images but that seems to not really work properly anymore. I'll try again soon.
Oh, lastly I also picked up a DMG ultrasonic 10 with the PH2 pallet/part storage system. I have completely run out of space and only have half of my machines here, and the other half at my other shop which I rarely go to since it's a shared facility and I wanted to reduce any exposure to the public and Covid, which is easy to do from my home based shop, where all the Deckel Maho's are.

The DMG 10 is pretty interesting in that it has an integrated Erowa ITS100 chuck in it's trunnion. Bot tilt and rotary axis are direct drive so five axis motion is very fast. It still uses lead screws but because the travels are so short it still is pretty quick. It has a Simens 840D Solutionline control on it, and I'm looking forward to trying to get the most out of the automation that machine has on it already.

My understanding is that the dental company that bought it new never did get the pallet changing functionality of it working. The machine is new enough (2010 I think?) that plenty of support still exists for it, unlike some of my other machines.

Normally I wouldn't want such a big machine for how small it's travels are (X120mm Y120mm, Z200mm) but when you have smaller parts to do that need milling work on all sides you can't really hold much more than 1 part on the table at once anyway. This way this machine still can hold 12 ITS100 pallets or something like 50 ITS 50 pallets? So even though it is one part at a time, it still is suitable for lights out production. It has a laser tool setter (finally) and a touch probe... and a 42,000 rpm spindle. I didn't come with any ultrasonic tranducers but I may invest in a couple to see if that extra capability will come in handy.

I had a Piblomulti speeder I bought off a buddy that just needed some cash for stuff he really didn't use in his shop. It's good for 30k rpm and I finally pulled that out for a job and was very thankful I had it! Tiny o-ring grooves on a job I had setup on tombstones to do 15 parts at once, that speeder saved me hours and hours and hours of machining time. One day I'll go to the effort to machine up the special parts so it can be loaded and unloaded into the tool changer, for now it's just a hand load M66 but much better than not having it!

Anyone that has experience with the ultrasonics feel free to share your thoughts. This one is HSK25 so I doubt there are many others out there used. It has the Schunk Tribos tooling in it now too, I need to get the clamping unit so I can change tooling, if anyone out there has anything for this please PM me! I'm considering other options for HSK25 too, I don't have a heat shrinker right now, so if that is considered I will be looking at the unit to go with it.

That is enough for now!
This is just a test to see if my ability to upload images is now functioning again now that I've upgraded my PC and my operating system. This is me and the MC800H back when I first started this project...

Well it is good to see the images are uploading again!

First and foremost: If anyone out there has a damaged spindle for a 2001'ish DMU eVo (50 or 70) that has a good stator please contact me and let me know what you want for it ASAP. I'm going to be pulling the trigger on getting the stator rebuilt starting later today but if someone has something that will work already I would consider that route too, price dependent of course.

So after a whole bunch of hours with my DMU50 eVolution I now have it powering up and moving around. I ultrasonically cleaned the large heat exchanger cooler for the glycol (massive copper unit that would be very expensive to replace!) and cleaned/rebuilt the entire cooling aggregate on the back of the machine. This took a long time, but at least now it will work as new in terms of efficiency.


Here you can see the rags the previous owner stuffed all over the base of the unit to capture all the leaking fluid going everywhere. The fans were caked with gunk and heat exchanger was almost clogged completely closed. The stuff that came out of the rad has varying consistency between clay and molasses and is extremely difficult to work with. It doesn't wipe off surfaces and I'm very thankful for ultrasonic cleaning technology otherwise that would have been very difficult to get as clean as it now is. I can only imagine what the lungs look like of the people that had to work in the shop this machine came from.


Here it's clean, the entire bottom tray is made from brass as is the cast heat exchanger that is used to take glycol to cool the heat exchanger that is mounted inside the control cabinet. What is nice about this design is the hot air inside in cabinet that rises from convection is cooled by the cooler at the best intake point. This machine they were smarter about mounting the entire control and drives near the bottom of the cabinet so the intake to them would be the coolest air in the cabinet. This is a major improvement over the 50V machines. I still would prefer a dedicated AC unit like the MC800H and my Ultrasonic 10 have, but this is better than before. Interestingly, the MC800H has it's heatsinks for the drives all getting air from outside the cabinet entirely. This is nice as the cabinet doesn't need nearly as much cooling and the electronics themselves (which suffer longevity issues by the higher temps) will last longer. Fanuc started doing this in the late 90's too and I think it is a much better way than the Siemens 611 system that has all the heat staying in the cabinet. One benefit of the Siemens design though is the heat changers and fans stay clean as they aren't taking in shop air. That is until the whole system starts running too hot and the operator starts running the machine with the door open. Anyway, I digress....

So early this morning it was "Arts and crafts" time. The stator on this Kessler spindle is encapsulated in epoxy. I may not do this myself once it is rewound but just in case I do, I decided to cast silicone molds of the original stator epoxy profile since making such molds is much cheaper and faster than if I tried to do this later.


It's funny, I literally looked around my shop/storage until I found parts that would work to seal the stator and not waste too much silicone. What you see there is the exact amount of 2 part casting silicone that I had on hand for another project that I didn't get around to. I took a turned steel part that I had with a profile that worked perfectly and tossed a 3in ABS drain pipe on it. I had some "dum dum" strip caulk that is non hardening that I worked around the interfaces between the parts and this is the result.

In a few hours I'll pull it out and proceed to press out the stator and start destroying that epoxy to remove the thermal sensor. My research has found there have been some great advancements in stator encapsulation so I may invest in some of the latest products to gain the thermal conductivity benefits they provide.

I must say that although I have had great reliability from the older 50V Kessler design (Knock on wood), this spindle is much better designed than the older ones. First, the actual tip of the spindle between the bearings is now cooled, like the MC800H. I always couldn't believe the 50V's didn't have any glycol going to this region, and instead they rely on the thermal comp in the control to keep machining in tolerance. This spindle not only has additional cooling, but it has the thermal sensor placed right near the tip as well. In addition, the spindle is air/oil lubricated instead of grease. Now I know this ultimately is more expensive because of all the air and therefore energy you will spend running this spindle, but what I like about it is that as long as you take good care of the system and your air supply, the bearings are always being "cleaned" while the spindle is run. Also the air/oil provides better cooling and constantly fresh lubricant. Lastly, it isn't as easy to damage the bearings from overheating or contamination like grease spindles. If coolant somehow made it through the three teirs of labyrinth seals, it wouldn't stay there for long enough to do any real damage, and certainly not contaminate like it would grease.

Also, these spindles no longer have two parts. Now this is not really a bonus in some ways. If you damage a taper the older design is cheaper and easier to fix, as you can have spare tapers on hand that aren't part of the motor section. The benefit of the newer spindle design is that the overall assembly is much stiffer, vibrations from cutting will be absorbed better by the spindle mass, and there is one less high precision ceramic hybrid bearing to have to purchase when replacing all of them. The newer spindle has a separate bearing assembly that allows for axial motion only of the top angular contact bearing. It's spring loaded to keep the balls preloaded and therefore less likely to skid and cause premature wear, but the bearing is free to move with almost no resistance so that any thermal growth in the spindle doesn't create any additional force on the bearings. On other machines, like the Kitamura, they used rollers instead because they do serve a similar function but you cannot really preload all of them so skidding would be hard to prevent. This design is much better. When I was researching information on this I came across a Deckel Maho patent that they applied to the later spindles that also allows the cables and bearing assemblies to be released by just a few socket head cap screws. On those spindles you can drop the entire spindle with bearings from the machine without removing the stator. This makes the labour cost of removing the spindle in the event of damaged bearings much less.

Then again, on the older DMU50V spindles, as long as the motor side bearings are fine, you can remove the taper section without even having to drain the coolant or anything. The downside is that you do have to disconnect the drawbar gripper whereas the newer design that can all remain fully installed.

That's enough for now, we'll see how this stator repair goes.

Dave @ Nerv
Hi, can you post some pictures from the spindle internals. The rotor of the spindle is moving lilt bit down when the hydraulics push the drawbar to relish the tool. I wonder if the bearings take all the force from the tool change or the rotor is resting on the stator during tool change.
You can clearly see this down movement of the spindle when the drawbar is pushed in some others spindle too.
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