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  1. #16
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    The penny dropped in regards the quill dogs, I removed one and mounted the boring head no problem.
    Photos show the set-up on the mill, and the finished product.
    Size is 28.3 mm diameter, and deliberately offset a little to maintain thickness on the slotted side.

    It was interesting to see the amount of spring in the bar, did two spring cuts and finished with a nice finish.
    80 RPM, 10 mm/min under CNC, 0.1 mm cut.

    Now to making a sleeve.
    I think I will glue the sleeve in the bore, then slit it - seems the safest option.

    Head Clamp Boring compr.JPGHead Clamp Bored compr.JPG

    John

  2. #17
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    Made the sleeve.
    During final dimension checks realized the Main Axle is dia 24 mm, not 25, so got an extra 0.5 mm sleeve wall thickness.

    Dia 40 mm extruded CI stock reduced to nice "glue loose" fit to the bored casting (tested on the lathe) and parted off a few mm longer than requirement.

    Held slug in a collet and bored out to dia 23.99/24.00 mm, tested as a neat fit to the Main Axle on the lathe.
    External diameter reduced 0.05 mm in the middle to act as a glue reservoir.

    Head Clamp Sleeve compr.JPG

    Packed casting gap out with some PVC shims, added an external engineers clamp, and glued the sleeve in the casting with Loctite.
    The clamp to guard against the glue possibly expanding the casting as it set.

    Ordered a slitting saw arbor and blade from Ausee.
    They didn't have dia 22 mm arbor dia in stock, so dia 16 mm it was, with a dia 12 mm shank.
    The arbor is fine, but the blade bore is dia 16.1 mm, a very loose fit.

    Mounted the casting/sleeve on the mill with quite a "Heath Robinson" set-up, but I was determined it was not going to move !
    A plug in the bore and the external clamp ensure the casting could not close in or separate relative to the blade.

    Head Clamp slitting on mill compr.JPG

    Calculated cut conditions:
    - cast Iron machining speed a conservative 10 m/min,
    - blade dia 63 mm requires speed of (10 x 1000) / (pi x 63) = 50.5 RPM,
    - mill set 70 RPM, VFD set ( 50 / 70 ) x 50 = 35 Hz,
    - arbitrary select chip per tooth as 10 micron,
    - blade is 48 Teeth but 0.05 mm off-centre, so (say) 24 Teeth do the cutting,
    - cut per rotation is 24 x 10 micron = 240 micron = 0.240 mm,
    - at 50 RPM feed is 50 x 0.24 = 12 mm/min.

    CNC on the mill has pre-set values for feed, 7 mm/min is the nearest.
    Could have done a re-configuration in software to get more feed, but considered not worthwhile.

    Hole in casting at end of slot drilled through the sleeve to match.
    Slitting job went without incident, 50 RPM and jogging with a mouse set-up on the table.
    A few mm short of the drilled hole because of geometric constrictions.
    Slot continued to the hole and cleaned up with thin files.

    Head Clamp Sleeved Slotted compr.JPG

    A piece of stock was brought down to dia 23.98 mm in the lathe.
    Installed the clamping bolt ( after a reamer to clean up slitting burrs ) in the casting and mounted it on the mandrel.
    Proceeded to face both ends of the casting.
    Very slow and carefully and no sign of slipping.

    Head Clamp end facing compr.JPG

    Inspected the Main Axle control head, operated it forwards/backwards, observed that the alignment marks look original, so decided not to mess with it.
    The observed friction between the knobs may be part of the normal operation.

    Main Axle control head compr.JPG

    I will now assemble the machine and try it out.
    Keep well,
    John.

  3. #18
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    72
    Posts
    3,102

    Default

    Some years ago I had problems finding suitable collets for my cylindrical grinder (from 1925) - which looked similar to yours but a little bigger.
    My solution was to use the one collet I had and modified it to take ER32 collets by reworking it completely. I brazed the slots solid and at the same time brazed a short tool steel ring to the face of the collet. I allowed the brazing to cool slowly, so as to somewhat anneal the collet 'springy' part to enable boring later on with carbide tools. I then ground the new collet end to the correct diameter for the ER32 nut thread and cut the thread on the lathe. Then I bored the whole assembly on the lathe to match an ER32 collet holder, leaving a few 1/10mm for final grinding in situ in the workhead of the cylindrical grinder. Now I couold get collets of all sizes for chips - or precision collets for reasonable prices.... You may be able to do something similar with a smaller ER collet series (25, 20 or 16 perhaps).
    Looks like a great machine!
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  4. #19
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    Joe,
    Your descriptions of a change to a different collet system is inspiring.
    You have now put out a challenge !

    My thoughts were to make a new top-section that was interchangeable with the existing.
    My mill is ER32, so that would be the obvious target.

    But first I have to actually grind the lips on a 12 mm end mill to educate myself on how this thing works.
    There are still mysteries as to what all the knobs actually do, and how to implement the manual approach/sweep actions.

    John.

  5. #20
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    Got my first cutter sharpened.
    The motor powered up nicely with a VFD.

    First Cutter 8May20 compr.JPG

    This cutter is a 12 mm 4-flute HSS ripper cutter that came to grief when I opened up a Clarkson Autolock style spanner to fit my Acramil chuck.
    Sparks, blue swarf and obvious distress. That metal was hard.
    That job was completed successfully with a carbide tool.

    The photo shows the cutter after the job it did.
    The job was to take a C-spanner made some time ago to fit my Erickson chucks, a simple hook in a piece if 40 x 5 flatbar, and to put some nice hand-comfortable shape to it, using the CNC Turret Mill.
    Slow feed and shallow cuts.
    A terrible burr was produced but the actual cut surfaces were 'Ok'.

    The job on the Tool Grinder was full of clumsy mis-steps and inexperience.
    But I started to get a feel of what was needed to achieve proper geometry and procedures.
    Time to start watching net videos and perhaps purchasing a Deckel operating manual.

    Once the end lips looked 'reasonable', I tried to set the machine to cut the gutters.
    But, I could not get the head close enough to the motor to enable a straight approach to the wheel, so they were done free-hand.

    Discussed with a good local machinist, I will get a square (not flared) cup wheel.
    He showed me some of his carbide efforts, something to aim for.

    Problems arise.
    The currently uncleaned original condition results in high friction everywhere- deadly for the soft touch needed.

    Then there is the mystery of the guide finger.
    The photo shows it projecting out into the work area.
    There is nothing to hold its position, mine slides in/out of its guide hole and freely rotates, with no sign of a clamping facility.
    Can anyone offer some suggestions on how this is supposed to be used.

    Guide Finger 8May20 compr.JPG

    John.

  6. #21
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    With mill work behind me, time to progress the tool grinder.

    Made a 6 mm collet, then a sleeve to adapt the 6 mm to 3 mm.
    The collet is good, the sleeve so-so.

    6 mm Collet 3 mm Sleeve compr.JPG

    Acquired a diamond cup wheel.
    Then tried to understand the machine with a 6 mm single-lip cutter that needed sharpening.
    How hard could it be !
    Spent some time fiddling around trying to understand the multitude of rotary and linear motions.
    None of it really made any sense, the whole machine seemed tight.
    I gave up and elected to strip the spindle head working parts down to see if I could spot any defects.

    Disassembly went Ok, but found some obviously seperable parts would only part company after a lot of persuasion.
    Build-up of greasy dust, dry bearings and burrs were cleaned up.
    Numerous dings etc cleaned away with a fine stone.
    Finally got to freeing the spindle from the spindle housing.
    Pulled/pushed by hand the end-stop assembly, then 'tapped' with a dead-blow hammer.
    Got some movement on the keyway, then stop.

    Conferred with a good friend, then put the job under his hydraulic press.
    2 T later, the parts separated, see the photo.
    We had sheared the key in two, part of the key retained in each part.
    Note that the keyway in the spindle is closed at both ends, so the key was captive to the spindle.

    Damage sustained in two areas:
    - the end-stop assembly had bulged out at the keyway,
    - the spindle housing had closed up a little around the spindle opening.
    Corrected the bulge with some delicate precision lathe work, and the opening with careful rotary flaps and frequent bluing.
    Trial test fits of the spindle in the housing and end-stop assembly were good.

    Spindle & End.stop compr.JPG

    Cleaned all the parts, so assembly can begin.

    There are two pin lock-nuts that tighten against the end-stop assembly to position the spindle against the housing.
    This positioning slides the end-stop assembly axially along the key against the housing end face.

    I am reluctant to re-assemble with a new key to replace the split one.
    There is plenty of metal for a couple of 4 mm grubscrews.
    Once the end-stop locates the spindle in the housing, the grub screws can be tightened.

    Spindle & Housing Parts compr.JPG

    Happy to get suggestions on how to arrange the grubscrews, or alternatives.

    Keep well,
    John.

  7. #22
    Join Date
    Oct 2001
    Location
    ACT
    Posts
    667

    Default

    Then there is the mystery of the guide finger.
    The photo shows it projecting out into the work area.
    There is nothing to hold its position, mine slides in/out of its guide hole and freely rotates, with no sign of a clamping facility.
    Can anyone offer some suggestions on how this is supposed to be used.
    John, your grinder looks like its basically a D bit grinder. not sure if thats already been said.

    The finger you refer to is for aligning a D bit in the collet. It doesn't clamp at all it remains free and you pull it out align the flat face of the D bit with it clamp the bit then retract the aligning tool.

    If you need to index a cutter just use the built in indexing that the work head has. Is easy enough to sharpen the bottom of a milling cutter. but space you have to work in is somewhat limited, not sure how much room your machine has...

    you should look for a Deckel SO grinder manual or similar as the construction and operation is basically the same.

    Cheers

  8. #23
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    Zsteve,
    Thanks for the comments.

    I have a Deckel SO parts manual and operating instructions.
    As you suggest, these will get me going.

    I sorted the finger thing after putting a cutter in a collet and examining how the two interact.

    I think I have sorted out (in my mind) how the indexing plate works with the angular offset ring.
    90 degree movements once the cutter is aligned with the finger appears to be associated with the two spigots on the index plate.
    But details are still a bit short on specifics.

    The angular offset ring is marked -40 / 0 / +40 degrees.
    This is fine for a single cutting lip, but the markings disappear with multi-lip after the index rotation.
    Now, I think this does not matter, as the offset for the first lip will be repeated as the index plate rotates.

    But, I have my doubts and decided to add a collet clamp to the housing.
    The clamp on the main body rotation shaft is M7 x 1 mm, so this is the thread added for the collet housing clamp.
    This is currently plugged, and the clamp can be added, if required, later.
    The photo shows the clamp plug in place, a possible clamp screw arrangement and the index plate showing the two spigots.
    Note that one of the spigots is coloured, and the housing incorporates a viewing window allowing sighting of either spigot.

    Collet Housing & Clamp Plug compr.JPG

    Keep well,
    John

  9. #24
    Join Date
    Nov 2019
    Location
    Brisbane
    Age
    69
    Posts
    452

    Default T & C video

    https://www.youtube.com/watch?v=neupF0-UnPo

    Hello from BC.
    I sent this link to a mate today and realised it would sit well there as well. 15 mins of good info.
    Think we could do with a tool grinding forum.
    Regards
    BC

  10. #25
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    Finished cleaning up with minor modifications.
    Now everything works and I understand the build of the machine.
    Photo:
    - rotating ring dimpled at 30 degree intervals,
    - side shift screw bronze nut added jack-out threaded holes,
    - C spanners for spindle end ring nuts lock.

    The dimples allow quick identification of rotations to 90, 120 and 180 degrees.
    The threaded holes enable extraction of the nut from its recess.

    Ring Marks etc compr.JPG

    At re-assembly found that the end-sleeve cocked sideways slightly when the grubscrews were tightened.
    Presumably distorted with the keyway bulge when it was separated from the spindle with the 2T press.
    This leaves the collet spindle firm for rotation at one spot, and very slightly loose opposite.
    Neither effect causes any problems.
    If problems are detected, a new part will be made.

    Tried to re-do the roughing end-mill shown earlier.

    Found that cannot set the tool past 90 degrees horizontal at either end of travel.
    So cannot grind tool on the dished wheel from inside to outside, only outside to inside.
    But, I now know how to modify the rotating head stops to get additional swing (if needed later).

    Also the vertical rotation is scaled for upwards swing, not downwards, but will allow quite a bit of angle to be set.
    Can add scribing marks on the scale (if needed later).

    Hand gashed the mill end on the narrow wheel on the outboard end.
    Then set it in a collet and proceeded to do a normal tip grind - no real problems at all.
    The photo shows the result:
    - good finish,
    - about 5 degrees of rake in the two directions,
    - the centre gash was too small and has virtually disappeared.

    My machinist mate has perfected drilling the HSS mills in the lathe to avoid gashing.
    This makes the tools non-centre cutting, but that is an acceptable trade-off.

    Second Cutter 1 compr.JPGSecond Cutter 2 compr.JPG

    Possible developments:
    - spindle speeds to 66 Hz (motor is rated 60 Hz),
    - additional horizontal swing to enable inside-to-outside grinds,
    - additional dial marking for vertical down rotation,
    - tool rest for the outboard wheel.
    - new spindle end-stop,
    - new workhead with a holder to 20 mm (perhaps ER32 collets).

    All in all, machine is now working without any known faults.
    Very happy.

    Keep well,
    John.

  11. #26
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    Reamed out the 12 mm collet to allow further insertion of the cutter.
    This provided additional tip clearance which allowed additional workhead depression, and addition of secondary clearance to the tips.

    First Cutter 9Oct compr.JPG

    I will work on improving my photography, it is much better than the photo !

    Found secreted away (forgotten) a complete set of imperial collets, and 3 part-made collets.
    Also two diamond wheels, two spanners (similar to what I had made) and 3 general purpose wheels.
    Note that the upper diamond wheel does have a curved surface.

    Diamond Wheels compr.JPGCollets Spanners compr.JPG

    Need now to make appropriate jigs etc to enable controlled gashing.
    I will try a 1 mm angle grinder cutoff wheel for this, with substantial side support washers.

    Also found the following odd collet.
    No charge posted to whoever needs it.
    Length 70 mm, Dia 16.5 mm, thread 16.15mm x 26 TPI, keyway 3.18 mm.

    Odd Collet compr.JPG

    I think I can now adequately re-sharpen lips on 12 mm end mills, which are the preferred cutter on my CNC mill.
    Keep well,
    John.

  12. #27
    Join Date
    Apr 2009
    Location
    Kingswood
    Posts
    930

    Default

    The odd collet turned out to be a Hercus one, and I have a Sheraton clone - so much for memory !

    Making progress with this machine, sharpened a couple of cutter lips and made a few single-lip cutters.
    Added a dimple in the spindle housing to show where the 90 degrees CW rotation point is (it just removes confusion).
    Will have to make some sort of dust shroud, as the "barbers apron" approach seems a bit agricultural.

    Ran into a problem with the 3/8" 2-slit collet.
    It would not draw up on a 3/8" blank.

    Decided the taper end of the collet was out-of-round the wrong way.
    That is, the diameter across the slits was greater than the diameter mid-way between the slits.
    On drawing the collet into the spindle, the diameter across the slits comes tight without collapsing onto the blank.
    Attacked it on the bench grinder and took some metal off at the slits.
    Now works fine.

    The 1/2" collet is also only 2 slits.
    Diameter across the slits is 0.04 less than the diameter across mid-way.
    It works, but really is a bit borderline (in my opinion).

    The photo shows the two collets, plus a part-made piece.
    You can just see the modification (butchery) on the smaller collet.
    The difference in diameters is now, of course, significant.

    Collets 2 slit compr.JPG

    How does one go about machining up a 2-slit collet with diameters different at the slits and at 90 degrees ?
    What difference is recommended.

    Keep well,
    John.

  13. #28
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,436

    Default

    Hi John. Guys,

    How does one go about machining up a 2-slit collet with diameters different at the slits and at 90 degrees ? What difference is recommended.
    As far as I am aware collets have a constant size both in the bore and on the outer surface below the taper. After turning they are then slit. It is only the thread at the tail end that pulls on the collet to collapse it against the taper.

    They can get distorted by over tightening or holding a non round part, or twisted if the wall is a bit thin.

    If you have ever looked at a 5C emergency collet, the slits are fastened so that the collet cannot collapse under tightening when drilling to size. Those fastenings are removed after drilling. They also only have a very limited collapsing size range.

    HTH.5C emegency collet.jpg
    Best Regards:
    Baron J.

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