Needs Pictures Needs Pictures:  0
Picture(s) thanks Picture(s) thanks:  0
Page 2 of 13 FirstFirst 123456712 ... LastLast
Results 16 to 30 of 188
  1. #16
    Dave J Guest

    Default

    Hi Ray,
    It will be worth the wait.
    From what I was told, the B models all came with the DRO's fitted from factory.I would have got mine without it if I had the choice, as I already had a 3 axis 4 scale DRO from my old one.
    These 52B models come with Ground Y axis ways (instead of half milled, half ground) and hardened tables. I found out about the table when I was cleaning mine up. I tried to file some of the table edges to clean them up, the file wouldn't touch it. I know the other 2 mills that I had weren't hardened but they were just the 52's. The very ends are not hard, so it's still easy to drill if you need to for the CNC conversion.

    The vertex rotary tables are pretty good quality, are you CNCing it? That chuck will be good for the horizontal spindle as well if you go that way, like Chich2 did to his.
    Dave

  2. #17
    Join Date
    Jun 2008
    Location
    Victoria, Australia
    Age
    74
    Posts
    5,080

    Default

    Quote Originally Posted by Dave J View Post
    The vertex rotary tables are pretty good quality, are you CNCing it? That chuck will be good for the horizontal spindle as well if you go that way, like Chich2 did to his.
    Dave
    Hi Dave,

    Bingo! you saw through my plans. I have a mental image of the CNC cutting gears with the rotary table, probably way too ambitious for me... come back in a year or so, and we'll see!

    It's a longer term goal however, I don't intend doing anything with the Horizontal spindle or the rotary table for a while yet. The XYZ comes first.

    I got the Mesa cards installed in the PC and EMC2 installed so I'll be back on that over the weekend. (except Sunday which is the HTPAA tool sale)

    About half an hour after leaving H&F, I thought, I should have checked the production dates on those HM52 mills... I'm wondering if the HM52B's are a different manufacturer, or different model from the same maker?

    Regards
    Ray

    PS The sale price was $4939, down from $5379, so saved $440 over regular pricing.
    Last edited by RayG; 20th Mar 2010 at 08:52 AM. Reason: added sale price

  3. #18
    Dave J Guest

    Default

    I was told they bought a container load of these mills from another manufacturer because of the problems they were having. I was also told there are 4 or more different manufacturers of this mill over there.
    That was a good price you got it for, it wasn't that long ago that you would have paid that for a non DRO model.
    Dave

  4. #19
    Join Date
    Aug 2008
    Location
    near Rockhampton
    Posts
    6,216

    Default

    Makes you wonder how much quality suffers seeing they change manufacturers all the time...

  5. #20
    Join Date
    Feb 2009
    Location
    brisbane
    Posts
    109

    Default

    Hi Ray,
    I am a little confused, is it the HM-52 or HM-52B that you are wanting to start with?
    Reason I ask is, yes, they are different manufacturers. Yes, there was 1 container load of them some time ago purchased for the reason Dave has said, of which there is none left in the country.

    If you are waiting especially for the "B" model machine, confirm with Melbourne that is what is coming in. If ETA is mid April they would be close to shipping, if not on the water already.
    I think it best to call the salesman who you placed the order with to make sure that what you are expecting is what will be turning up.

  6. #21
    Join Date
    Jun 2008
    Location
    Victoria, Australia
    Age
    74
    Posts
    5,080

    Default

    HI Brisbanefitter,

    The order was for the HM52B with 3 axis DRO, I got the sales guy to make a note on the order to the effect that I was specifically requesting the later HM52B model.

    Although, on reflection, I wonder if the "B" might not be indicating the manufacturer rather than the revision number.

    Is there any way to tell which manufacturer made a particular HM52? maybe serial number or something.

    Either way, whatever the model number is... I am looking for the one with extra ribs in the base casting to minimize the problems that chich had with column to base flexing during his CNC conversion, and quill slot to minimize quill rotation, better tolerances and run-out on the quill. hardened and ground ways as per Dave's observations, and of course a table that's not warped.

    Now I'm off to the HTPAA tool show.. got a rust addiction to feed..

    Regards
    Ray

  7. #22
    Join Date
    Feb 2009
    Location
    brisbane
    Posts
    109

    Default

    The B was used to differentiate between different machines, I think sourced through different agent (dont quote me on that I am not 100% sure) and I think different manufacturer. There is more than 1 mob over there making these machines, as has been stated previously.
    They also carried a different stock code.
    If I was in your shoes, I would definitely make the phone call and double/triple check it is a B model coming in as I am not sure if they are. 10 minutes now could save lots of issues in about 6 weeks time, if the machines on order are not B models.

  8. #23
    Join Date
    Jun 2008
    Location
    Victoria, Australia
    Age
    74
    Posts
    5,080

    Default

    Hi Brisbanefitter,

    Thanks for the advice, much appreciated.

    Regards
    Ray

  9. #24
    Dave J Guest

    Default

    Hi Ray,
    Just wondering, did they confirm your order of the B model, or have you been resting up that hand?
    If you don't mind me asking what sort of money are they asking for the 12mm aluminum plate? Do they sell it by the square mtr or half/full sheet?
    Dave

  10. #25
    Join Date
    Jun 2008
    Location
    Victoria, Australia
    Age
    74
    Posts
    5,080

    Default

    Hi Dave,

    I got the 6061 T6 Al plate from these guys, Performance Metals Australia- Stocklist- 6061-T6 Plate with GST and freight, it was just over $500 for 1.2 x 600. 12.7mm thick. I can't really say if that was a good price or not, everyone else I chased up didn't stock it. I've overordered a bit, since I have a couple of other projects that a bit of 1/2" hi-tensile Al will be good for.

    The order for the mill is for a HM52B, I've confirmed that what's on the order, if something else turns up then, I'll make a decision based on what I see and measure.

    Regards
    Ray

  11. #26
    Join Date
    Jun 2008
    Location
    Victoria, Australia
    Age
    74
    Posts
    5,080

    Default

    Hi Dave,

    Price of 1/2" 6061 Aluminium Plate.

    Just as a rough guide, you could work on $750 per square meter, from Performance Metals including GST and freight.

    Enco, in the US sell 12" x 12" x 1/2" 6061 for $US61.98, that works out to roughly $A740 per square meter, but doesn't include freight.

    So it looks like the price is in the ball park (for small quantities at least).

    Just a rough calculation, but I am guessing the motor mounts will cost me about $50-60 each in material. A bit more for the Quill, because there is that big plate that goes at the top.

    I have taken the plunge and ordered ball screws, 3 ballscrew RM2505-921/764/539.4mm with end machined - eBay Replacement Parts, Metalworking Tooling, Manufacturing Metalworking, Business Industrial. (end time 08-Apr-10 17:40:49 AEST)

    Also this one. http://cgi.ebay.com.au/ws/eBayISAPI....=STRK:MEWNX:IT

    A bit more than I think I need, they are 25mm x 5mm pitch, the lengths are 1200, 921, 764, 700 and 539. The extra's are destined for another project.


    Regards
    Ray
    Last edited by RayG; 24th Mar 2010 at 10:36 PM. Reason: ballscrew changes

  12. #27
    Dave J Guest

    Default

    Hi,
    I got $320us and $480us for the same size piece you got, so about the same price over their.Per bracket doesn't sound much but it all adds up.
    I just thought I'd let you know (in case you want to change your order) that the standard screw length in these machines is 1250mm. I bought a 1350mm long one for the X axis as I 'm not sure on my mountings yet. I plan on leaving the hand wheels in place after the conversion so I will probably need a bit extra as well.
    I wasn't sure whether to order 16mm or 20mm for the quill, as I think the 25mm I bought might be an over kill for the job.
    When I ordered I bought 2 nuts per axis to load them up against each other, he charged $28US each for them.
    Dave

  13. #28
    Join Date
    Jun 2008
    Location
    Victoria, Australia
    Age
    74
    Posts
    5,080

    Default

    Hi Dave,

    Thanks for that, I have asked if they can increase the 1200 to 1350, I was going by the table size 1000 x 240, but allowing some extra length for the hand wheels is a good idea.

    I'm not sure I understand why 2 ball nuts are better, I thought the ball nuts could be preloaded individually?

    Ah.. I see a joke hiding in there about 2 nuts, (balls), but I'm trying to ignore it....

    Also, I'm assuming that the thrust bearing set up will be basically the same as the acme lead screws, have you looked at that part of it yet?

    Regards
    Ray

    Edit 1: Wow, that was fast, they have changed the order already to 1350, no extra charge... very impressed.

    Edit2: I think I answered my own question, these are not split nuts (as far as I can tell) , so preload is not adjustable.

  14. #29
    Dave J Guest

    Default

    Hi Ray,
    Standard nuts have ball bearings in them that allow a small amount of backlash.
    The ones off him that he calls anti backlash are over sized ball bearings in the same nuts that take out most, but not all backlash.
    There are a few ways of doing this with 2 nuts, one is using the 2 nuts (either standard or anti backlash) you can load them up by placing bevel washers between them to take out all backlash as you can load them up against each other until there almost locking. Here are a few links that I could quickly find with pictures.
    LEADWELL CNC MACHINES MFG., CORP.
    Rockford Ball Screw
    If you need more info I could chase it up for you tomorrow.
    Chich used the standard trust bearings with no problems but I will be using 2 angular contact bearings.
    2 Bearing 7204B 20x47x14 Angular Contactall Bearings:VXB
    That was good of him with the extra screw, he is pretty good like, that and it saved you around $10
    Dave
    Edit
    In the first link click on( Double Nut Designed Ball Screws)
    And in the seconed click on (pre loded in the drop box)

  15. #30
    Join Date
    Jun 2008
    Location
    Victoria, Australia
    Age
    74
    Posts
    5,080

    Default

    Hi Dave,

    Your plan sounds like a good accurate set up, I have been reading up on ballscrews, with those links you provided.

    Here is a basic introduction to ballscrews, good info for a beginner like me. Ballscrew Basics - Page 8 - CNCzone.com-The Largest Machinist Community on the net!

    With your set up you should be able to get pretty much zero backlash with the way you described.

    I understand that you can calibrate the ballscrew against the DRO and load that table into the CNC software you can have the accuracy of ground ballscrews (or better).

    Any ideas as to how much backlash there is in the standard thrust bearings?

    Regards
    Ray

Page 2 of 13 FirstFirst 123456712 ... LastLast

Similar Threads

  1. Hafco Hm52 on the fritz again
    By Retromilling in forum METALWORK GENERAL
    Replies: 25
    Last Post: 12th Aug 2009, 11:14 AM
  2. CNC conversion
    By sonic_racing in forum METALWORK GENERAL
    Replies: 7
    Last Post: 18th Jan 2009, 03:11 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •