Chapter one
Introduction by Web Site host:
What can be seen here below is the beginning of an ambitious project currently being undertaken by an individual in the UK. What is being done here can not be recommended for the average Hobbyist. As a matter of fact it must be strongly discouraged that anyone try to do something similar without significant experience or technical background. Way too many Deckels have become victims to botched conversion jobs, only to be reduced to scrap in the end.
So enjoy the following descriptions, see what can be done, but be strongly warned against misguided imitation.
Converting an FP4ATC to a Heidenhain Control, while eleminating the Tool Changer
5th August 2009
Machine: Deckel FP4ATC
Control upgrade to a Heidenhain 415, and conversion of the machine to single phase 240 volt input.
Machine’s original owner: Suffolk University (possibly a spin-of company)
Unfortunately the tool changer has to go due to space constraints but I never intend to run the machine in production conditions anyway… so really the machine will be a FP4A
I was introduced to the ‘Deckel’ family of machines by a friend of mine and I finally owned a manual FP3 after many years of searching, due to space I purchased a Bridgeport interact 1 Mk 2 machine for some time but was always on the look out for a suitable Deckel CNC.
On the 14th of July 2009 I located a machine on the internet in the UK (my birthday incidentally) and purchased it on the 15th with agreed delivery date of the 5th August.
With working on a project in Germany (machine tool related) I only had a handful of days to sell my Bridgeport…. Everything worked out fine after a enormous amount of time and effort spent organising… I even decided to relay my workshop floor with another 100mm of concrete and water proof membrane, so I booked 4 days of work and set too…….. 4 days later I was totally exhausted but had my deckel….. This was just the start!
Machine arrived; tool changer and panelling plus the electrical cabinet covered my entire driveway for three large cars!!! What Have I done?
Picture 3: Deckel FP4 CNC + all the other stuff that came with it (were do I park my cars now)
The machine was instantly covered and sheeted as it would have a 3 week wait until it gets moved across the dive into its final resting place. (we didn’t have one drop of rain until after the machine was moved!)
The panelling was stored in my shed just leaving me with the tool changer and machine control cabinate to contend with.
Fighting the English weather it was decided to pull the control cabinet in to my workshop in-case of a heavy downpour, once this was resolved. We attacked the tool changer and reduced it to nuts and bolts within about 3 hours.
Picture 4: Deckel FP4 CNC (Electrical Cabinet)
Tool changer comments
This unit is of a truly massive construction and the mechanical complexity but also the quality is truly remarkable, from the shell cam turret indexer with its 1KW motor through to the hydraulic tool clamping and loading arm.
Picture 5: Deckel FP4 CNC (Hydraulic Power Pack in tool changer)
Inside the tool changer cabinet body lies the 2.2Kw hydraulic pump motor and valve assembly, + air filter regulators and distribution board for sensors solenoids etc. all hoses were drained and stored away along with a other components, unfortunately the hydraulic power unit for the toolchanger also provides the pressure for the vertical and horizontal drawbars ….. dam it…
Picture 6: Deckel FP4 CNC (Removing the tool changers carousel)
Picture 7: Deckel FP4 CNC (Nearly stripped down)
Conventionally deckel like to submerge the pump in a casting pocket in the base casting of the machine. As I don’t have this pump unit I will have to contend with starting a 3HP motor every time I need to change a tool (I can feel my carbon foot print getting larger).
Martin to the rescue!! lucky for me he was breaking a FP4A so a spare hydraulic unit become available . good news for me and my electricity bill!
Picture 8: Deckel FP4 CNC (Hydraulic Pump)
With the tool changer in component parts I was able to turn my attention to stripping the electrical cabinate… again within a few hours everything was out…. Sorted into wire / relays/ contactors/ transformers / resistors / rectifyers / etc etc etc the empty cabinate was ejected from the work shop and I continued with relaying the floor in my workshop!! (I certainly know how to make like difficult for my self)
Picture 9: Before
Picture 10: After
Once the floor laying job was out the way I continued to prepare for the big move.
This involved what I call a first stage clean on the actual machine, removing all sludge from the sumps and old smelly oil + swarf particles. Every cover was removed to give me unrestricted access to the hard to reach areas, the machine wasn’t that dirty considering its age and the more I looked at the machine I realise how little the university used it.
Before going any further I rigged up the central lubrication unit ‘Willy Vogel’.... and relentlessly turned the pump unit on an off until the machine was dripping in oil…. I also released all the oil unions slightly to ensure each was getting oil to the outlet. The oil from the vogle unit charges small piston accumulators that once the Vogel unit gives it short burst of pressure, the accumulators can still provide a positive supply of oil until the next PLC command to run the lubrication unit
With this done I though it would be a good time to move the axis around and get a feel for ball screws and any other issues. Connecting the 4 bare motor wires into pairs to my portable bench top DC power supply. Everything appears to be in order with even / steady current consumption across the axis travel.
The X- axis did show 0.05mm backlash, after retightening the ballscrew nut (it was loose) this was rectified.
Picture 11: Machine moving
Picture 12: chain + Rope + rollers = moving machine
Picture 13: fitting table
Picture 14: My Manual FP3
Picture:15 Machine in position
The Heidenhain 415 Control
Picture 16: Heidenhain 415 Control
The heidenhain control for ‘me’ the best, and is perfect for what ‘I’ want to do with the machine. I am in no way putting any other control down if you’re happy with your Grundig / Fanuc / Siemens that’s great.
The conversational programming format and ‘free contour’ programming aids are excellent; combine this with Mathematical Parameter Programming and you can achieve in a few lines what would take ten thousand lines with a cam system… I do use CAD (SolidWorks) and many different CAM packages but the heidenhain can nearly always be used to create what you want.
Back to Basics
Now I own a set of ‘Deckel Castings’ with some bit’s of cable hanging from it…. Where do you start?
The answer is I don’t really know!
But getting some power on the Heidenhain was as good a point as any; a friend helped armed with some very basic PLC code to let us move about the control. A mock-up E-Stop relay and NC Start microswich was used to get things moving and try to get some parameters entered into the control.
Power and Drive
With the issues of not having 3 Phase the FP4A with its DC servo motors are an excellent option as you can’t get more single phase than a DC motor!
There are many PWM drives available some with a single phase input or 3 phase input but with a DC Bus input option also, in this instance Control Techniques Maxi Maestro drives have been used in collaboration with a large DC power supply to provide the DC bus .
The Power supply currently comprises of a Large 5Kva transformer to step down the 240 volts (some times creeping to 250 volts in my neck of the woods) to 150volts AC, then through a beefy rectifier to charge two large capacitors, this forms the basis of the DC bus for the dives.
Initially the motors and Tacho’s were connected to the drive (being sure to leave the axis in the middle of the machine travel in case the tacho was not connected correctly, or the axis will run away at top speed!! Be warned) the drives were set up following well documented procedures and the aid of an oscilloscope.
Picture 17: if you look close though the Rats nest you can see a test DC power supply for the drives
Picture 18: Heidenhain and drives
Finally after fighting some gremlins and getting my head around the referencing system of this machine (only one limit switch on the x and y axis….. no reference dog’s or switches!) I managed to convince the heidenhain to handle this setup… with the machine referenced and the software limits set I was now able to move the machine round for the first time!..... Manually I kept the central lubrication system working to ensure I’m getting oil to the machine.
Axis testing
I have been lucky enough to purchase a Mahr Millitron probe system that can give full scale readings down to + - 0.3 Micron full scale deflection, I’m not saying its that accurate (Ie nanometres) but these LVDT probe are analogue and the readings analogue so the resolution is very high and I would say the repeatability is also very high.
I can now see how the machine dynamically responds to very small jog commands relative to the machine table… with the handwheel working I was jogging with 0.0001mm increments, and giving incremental moves of 10mm also and asking to come back to a 0 position. The machine responded very well, When given a position command (say 5mm move) the machine would over shoot by 1 micron then come back to the desired position… interesting to note that the Y axis becomes stiffer the further out it is (in terms of no load movements) due to the ballscrew distance between the nut and the clamped support gets shorter and produces less twist and stretch in the screw. This can be seen to its full extent when the Y is completely back (Y+ Max) and the Probe will oscillate 2 microns and settle to its final value after afew seconds.
Picture 19: Mahr Millitron Probe Readout with potential for 0.00001mm resolution (that’s 0.000000393” for you imperial guys)
This measuring exercise was conducted to give myself a good indication of how it performed in relation to my Bridgeport interact….. I would say it outperforms it by a factor of ten. This conversion will be money well spent I think.
Lot’s has happened over the past 10 weeks but it will become quieter over the coming months due to the large amount of mechanical and electrical building work that needs to be done…. I still need to find an electrical enclosure! And I have many auxiliary items to get working. Depending on the response to this work on the website will dictate the amount of detail I put into my descriptions and updates, if there is sufficient interest I will add more detail to what already up and increase the level as I go along
