VMC Mill Discussion - Page 4

Page 4 of 15 FirstFirst 123456714 ... LastLast
Results 61 to 80 of 295

Thread: VMC Mill Discussion

  1. #61
    Gold Member LeeWay's Avatar
    Join Date
    Jun 2004
    Location
    United States
    Posts
    6618
    Downloads
    2
    Uploads
    0

    Default Re: VMC Mill Discussion

    Okay.
    That is totally plate. It looks like a tuning fork to me.

    We all clearly have different ideas about how it should be done.
    I built me 80/20 mill mostly to prove the concept, but also because of the ease of using it. It works fine for the size machine it is with the obvious spindle head of an X2 being it's weakest link. Even with that, it manages 6600 RPM and does machine steel at semi-production rates. Maybe Uber-hobbiest rates.
    Not as well as the Torus or the Pulsar, but certainly usable results.
    It has nice parts added to it's base. It has similar size constraints.
    14" X 9" Y and Z. Could use a little more Z height. The machines footprint is pretty big for this size machine though.

    That can be done better. I do want to design a base using a combination of cut to length tube and plate. I am willing to use the good parts of my 80/20 to do it. It would, however be a one off as well.
    That said if it's an open source design that stops at the motors, it might translate well to other garage shops needing a solid little machine.
    I would like to design it in SolidWorks though. Give me a chance to give that software a little exercise.
    This will take me some time. I just don't have a lot of it. Who does?

    Nice to see some designs coming in here though.
    Keep them coming.

    Lee


  2. #62
    Member Tkamsker's Avatar
    Join Date
    Oct 2010
    Location
    Austria
    Posts
    1189
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Hi G59 i saw your drawing
    here is a foto of my machine
    i personally think your base is not wide enough.
    like it was stated by others we will have an steel box design and an Z Axis upright
    VMC Mill Discussion-20140805_211222-jpg so i think the foto gives a good impression of an proven state of the art design ? Right ?
    I also think of maintenance of the machine what to put where.
    but i now really have to think of best fitting server controller combination to drive such machine best ,..
    Because i had a thought if people really want mold making do alu or steel molds they will work with small cutters high speed
    and i think therefore high speed cutting is really required. So i now have a look at servos
    so i think of 2 driving sets
    1) Steppers
    the idea is to have kind of standard or private use setup where cheap and reliable is paramount
    is an Triple Beast driver with 3 Steppers and 40 v PSU controlled by an PC via LPT Board. (yes it could use Mach if needed -
    the setup would be in my case an linuxcnc config which drives the 3 axis motor left right speed flood, light hand wheel on the box
    the idea here is to have an setup with manual tool change
    and in that setup depending on the head a lot is possible
    so my thinking of Head is coming later but in the actual setup the machine could be used manual and cnc so a quill exist and the spindle is ISO30 (because i use an existing machine to 80%)
    in that setup the steppers are driven in 1n 1:3 ratio belt drive which works very well.

    2) Servos
    i have very good results with general mechatronics so i would build on my experience and reliability in the factory
    this setup would be an pc with the FPGA Card in it an server drive and to be defined servos which dictate the PSU.

    So in that setup my question to you would be is it better (in cost and reliability ) to use for instance this size of motor Low inertia AC servo motor, 400 W | Granite Devices Online Shop
    which adds 1000€ only in servos around 400€ of drivers and ? for PSU for just control that machine but it will be really fast.
    the question then would be direct drive or gear ?

    3) Motor mount & spindle
    i have to think of and group it
    thomas



  3. #63
    Member handlewanker's Avatar
    Join Date
    Sep 2006
    Location
    Australia
    Posts
    6463
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Hi kam. I cannot answer your question regards the stepper/servo preference as I don't have experience with either, but personally I would use steppers for the machine being "designed" as it seems like a simple well used and easily obtainable approach to a simple problem without getting too high on the dollar or Euro outlay or making complications where a KISS approach is always the best........the aspect of the drive mechanism type is a personal one once the basic machine carcase is constructed as was mentioned in previous posts..........going to fine detail at the early stages is not establishing the basic build structure which is necessary for a starting point.

    G59.....that is almost exactly as I envisage a steel plate build to look.......except it would have the column separate from the base section, not as one piece as shown in the drawing.

    The column part in your drawing has function as well as appearance to make it acceptable for the common build in plate stock all welded together.

    If the column was welded to a 20mm steel base and that bolted to another 20mm steel base plate that was welded on the base itself....I think it would work as an item you can adjust to get the Z axis square to the X and Y.

    By that I mean if the column is bolted to the base and has a few thou run across the X or Y axis planes, it will be simple to adjust the base interface by either re-machining it or hand scraping to get the axes true.

    It still exist in the drawing as a pure hollow box, but as such would be simple to get cut with Oxy Acc even if laser or other cutting methods wee too expensive.....personally I would just get the plate sections guillotined from stock material and then welded together.

    Looking at the hollow box on a base design with the top also closed in with a cap, and you can embellish it further to resist any spring in the box structure by a few internal round bar cross braces strategically placed to give it corner to corner strength, mainly to firm up the box framework.

    All it needs to completer the column build would be 2 steel strips for the rail seats and probably 2 pads for the ball screw support mounts.

    I think steel strips need to be added to give the rails and bearing blocks the height behind the head to clear the ball nut housing as the head goes up and down.......it being easier to skim machine the face of the steel strips than machine two grooves into the face of the column.

    Next the base, in it's simplest form, is just a rectangular box with two side members welded on the bottom to give two bolt down feet and the top with two steel strips for the rails and a 20mm steel plate for the column to bolt down on........the bolts will need to be inserted from underneath.

    Having the bolts inserted from the bottom means you don't need to have the column base plate wider to put bolts through from the top and enables the column sides and base to be flush at the bottom.....it looks neater and fits better.

    No way would I ever fit the Y axis stepper motor at the back of the column to save frontal space....it's a complication that is not warranted unless personal choice dictates it.

    Last item for basic construction is the head.
    Ian.



  4. #64
    Activation process G59's Avatar
    Join Date
    Aug 2014
    Location
    Canada
    Posts
    889
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    As I said, this is only the base, column and center section. Of course it is too narrow. I have very little time so I can only draw so much in 10 minutes. Here is the next stage.
    VMC Mill Discussion-part1-1-jpg

    Yes it is all plate.
    The reason for one piece column/base, is strength.

    Handle, The Y axis motor can easily be mounted in the column with no complicated fabrication or hampering of serviceability.

    TKamster, I will leave your thread alone from here on, I think you have an idea and you should just follow through with it. I'll continue to watch this thread but you seem to have it well under control.

    BTW a 750 watt servo would be more than enough to manipulate the Z axis and have good control over kinetics or inertia with a 50kgs load in vertical. I think a 400W servo could do well, although not as quick.



  5. #65
    Banned
    Join Date
    May 2007
    Location
    us
    Posts
    29
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    design the mill with the y motor in the rear like professional equipment, little hobby toys have it sticking out the front. keep in in back away from the muck and a cleaner footprint in front where you work. it requires no special complication other than a hole for the ballscrew.



  6. #66
    Member handlewanker's Avatar
    Join Date
    Sep 2006
    Location
    Australia
    Posts
    6463
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Hi, I would be extremely wary of having a base and column in one piece.......strong in some aspects yes, adaptable to adjustment for alignment of 3 axes ....no.

    BTW, adding the two side members to the bottom of the L to increase the width of the base does nothing for the frame strength as the base is now only attached to the column by the original centre two L section extensions.

    Granted this is only a quick design concept, and as such needs to be evaluated and improved on, but non the less it's up for consideration having been proposed as a design concept.

    The other side of the coin is the side form that is made from one piece of "L" shaped sheet material.......no steel fabricator would wear the cost of the left over scrap when the two side pieces are laid out on the sheet and cut out........it also does not lend itself too freely to be cut by guillotining the plate to the shape indicated in the drawing.........this is a job for a cutter, either water jet, laser, plasma or Oxy/acc, and no less than 10mm thick plate would be in the frame as suitable.

    It "could" be made with 2 pieces seam welded to give the L shape....whatever..... but the bottom, where the base becomes the lower leg of the L, needs to be looked at.

    I think, for the money, steel tube is the strongest contender, having all the attributes that are needed for KISS construction techniques without the problems of handling a one piece composite structure.

    Just machining the linear way seats for the Y and Z axes would stress the average machine builder unless he had a large machine capable of handling a relatively large piece of fabrication needing machining to extreme accuracy in more than one plane.

    If this design was a consideration for a production item, then the final linear way machining needs for accurate alignment, not only as a final outcome but as a manufacturing process would take more time than the entire machine took to fabricate it, and there is no provision to re-align any axis if there is a deviation from squareness in any axis.

    This is one design for consideration and no doubt there will be many more.
    Ian.



  7. #67
    Member handlewanker's Avatar
    Join Date
    Sep 2006
    Location
    Australia
    Posts
    6463
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Quote Originally Posted by frigger View Post
    design the mill with the y motor in the rear like professional equipment, little hobby toys have it sticking out the front. keep in in back away from the muck and a cleaner footprint in front where you work. it requires no special complication other than a hole for the ballscrew.
    Hi....have you considered that the design I proposed was steel tube orientated....probably not.

    To build on a steel tube base you need to add a thick base plate to mount the column on.......that means the ball screw shaft needs to be longer to pass through the front wall of the COLUMN but above it's base mounting plate.

    Ball screws are supplied made from continuous lengths of screw stock, and have the ends machined to standard dimensions for the ball screw mounting brackets and are not made with plain extended custom dimensions like you propose.

    If you think that is a good design idea, count me out......machines in industry that are constructed with this method are made from castings and not steel tubing.

    I assumed the idea for simplicity and effectiveness was KISS.
    Ian.



  8. #68
    Banned
    Join Date
    May 2007
    Location
    us
    Posts
    29
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Quote Originally Posted by handlewanker View Post
    Hi....have you considered that the design I proposed was steel tube orientated....probably not.

    To build on a steel tube base you need to add a thick base plate to mount the column on.......that means the ball screw shaft needs to be longer to pass through the front wall of the COLUMN but above it's base mounting plate.

    If you think that is a good design idea, count me out......machines in industry that are constructed with this method are made from castings and not steel tubing.

    I assumed the idea for simplicity and effectiveness was KISS.
    Ian.
    i don't particularly care what you think, this is tkamskers thread and his design project. if you think your way is the only way go start your own thread. i don't see anything set in stone as far as design constraints are concerned. he has mentioned a steel box not your tubing. putting the motor in front makes little sense, this is a cnc mill not a manual you need to crank handles.



  9. #69
    Member handlewanker's Avatar
    Join Date
    Sep 2006
    Location
    Australia
    Posts
    6463
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Whatever........go read post #1 again.



  10. #70
    Banned
    Join Date
    May 2007
    Location
    us
    Posts
    29
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Quote Originally Posted by handlewanker View Post
    Whatever........go read post #1 again.
    yep, i did.
    Machine Frame :
    there was an discussion if it has to be casted or can be welded in steel.
    I think it depends of the quality of steel if you have good quality steel why not weld it there is an given wall thickness you need for the needed strengt.
    So in my opinion there is no need of cast for an VMC mill
    nothing there about steel tubing, that's all you, if that's what you want, start a build thread and show us. your opinion isn't the only one that matters.



  11. #71
    Activation process G59's Avatar
    Join Date
    Aug 2014
    Location
    Canada
    Posts
    889
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    BTW, adding the two side members to the bottom of the L to increase the width of the base does nothing for the frame strength as the base is now only attached to the column by the original centre two L section extensions.
    The two sides weren't meant to strengthen the uprights. It was to increase the base width as the previous complaint by someone who couldn't envision what I was trying to get at.

    The other side of the coin is the side form that is made from one piece of "L" shaped sheet material.......no steel fabricator would wear the cost of the left over scrap when the two side pieces are laid out on the sheet and cut out........it also does not lend itself too freely to be cut by guillotining the plate to the shape indicated in the drawing.........this is a job for a cutter, either water jet, laser, plasma or Oxy/acc, and no less than 10mm thick plate would be in the frame as suitable.
    I can tell you have dealt many times with purchase of steel plate. Suppliers sell it by the pound or square footage. Of course my design needs to be cut. I'm sure I said so somewhere.

    design the mill with the y motor in the rear like professional equipment, little hobby toys have it sticking out the front. keep in in back away from the muck and a cleaner footprint in front where you work. it requires no special complication other than a hole for the ballscrew.
    Right on the money. That's the difference between hobby and a real machine. The placement to the rear complicates nothing and adds no more than $25 to 50 dollars more to your build. It also reduces overall foot print and keeps the motor out of coolant, chips or object strike.

    This is one design for consideration and no doubt there will be many more.
    I totally disagree with steel tubing construction. It's too simplistic and your machine will end up with too much dead weight and usually ends up looking like a pile of tubing . For myself, aesthetics are important if building a cnc that will eventually be for sale.

    Like I said handle, I used your dimension criteria. Personally, I would never go with them, just thought you would get a visual of it in 3D.

    Again, I'm not picking on anyone. But I have my own machine build to contend with and being that everyone's an engineer here, I will go my route and post a completed machine sometime next year. And yes it is completely made of plate steel and has no resemblance of what is being proposed here. Being that I want to sell my design and manufacture it for sale, of course I won't share it on this thread. For me, I'm watching this thread to see if I missed anything.

    Good day.

    You never know what you can learn from the general machinists.



  12. #72
    Member handlewanker's Avatar
    Join Date
    Sep 2006
    Location
    Australia
    Posts
    6463
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Hi, so very true, we can all learn by someone else's point of view.

    I believe, and may be wrong on a number of points here, that the UMC-10 is completely tube construction and has been, or was, offered as a saleable item, of which by all accounts is no longer available or even on the market......I believe the selling price was out of sight too.

    BTW, putting the stepper motor or Y axis drive under the column increases the length of the ball screw, and if you are going to invest in a high quality ball screw, expect to pay at least 1/3 more.

    As far as this discussion goes......did I say discussion......someone told me bluntly that it was Tkamsker's personal thread for a build he wishes to indulge in....I appear to have got the title of the thread wrong and should not have dared to voice any alternative construction methods while he was fishing for clues to create his own design for possible commercial gain.
    Ian.



  13. #73
    Member Tkamsker's Avatar
    Join Date
    Oct 2010
    Location
    Austria
    Posts
    1189
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Hi
    handelwanker and G59 i think that every opinion (even the march one counts
    and G59 i think it is also ok to make your own design and show or deont show it when it is ready.

    in my case skyfire (and the fail) inspired me to see if that kind of endeavor is possible in europe or not (and i really mean in europe) not selling china build stuff where you have then to refurbish it to some extend before you give it to the customers. to be honest i still don't know if this is or not.
    and i also believe that there doers and talkers
    so if you have a design and work it out then this is great i think it is all about achievement
    i also believe that all this forums in the internet are about to learn from each other some have more academic some more business some more hobby direction but the base is interest and learning.

    i looked to a lot of the machines and try first to understand why have they chosen that or that and why did they do this decision
    and also to learn what do people need who want this kind of machines.
    i also will take the next step and do an servo machine with atc ISO30 but with my learning it will be designed to have even 50.000rpm spindles as well if needed.

    So i really like all ideas and comments so i hope to encourage still to share thoughts and opinions

    i am now in the design phase for the head (and servo ) part

    here a short video of the spindle raw from the builder

    if someone has an godd source for servos running with uhu controllers this would help
    me
    thx
    thomas



  14. #74
    Gold Member LeeWay's Avatar
    Join Date
    Jun 2004
    Location
    United States
    Posts
    6618
    Downloads
    2
    Uploads
    0

    Default Re: VMC Mill Discussion

    I was confused as well about the intentions of the thread, but at this point, it is totally blown up if it was a singular build thread by Thomas. Apologies.

    I do like seeing the different design concepts. I can tell you for a fact that there is not a right way and a wrong (well there can be a wrong way) way to build a machine. There are tried and true methods and designs.
    I don't think that any of us in this thread are discussing anything new. Most of these similar designs have been discussed here at the Zone before. I don't think you can have too many discussions on basic machine designs or fundamental machine building threads.

    As for the Y motor in front or back, I have had them both ways and I will say that I am all for rear mount. The screw need not be much longer than typical as long as the design allows it.
    This image is the back of my Pulsar and I gotta say it is nice. A similar Y setup would be done on a machine I designed, though it would have more substantial column to base mounting points. I mean this works great in cast iron as designed, but lesser materials would need more meat. A different type mating design.



    Lee


  15. #75
    Registered
    Join Date
    May 2007
    Location
    Netherlands
    Posts
    99
    Downloads
    0
    Uploads
    0


  16. #76
    Member Tkamsker's Avatar
    Join Date
    Oct 2010
    Location
    Austria
    Posts
    1189
    Downloads
    0
    Uploads
    0

    Default Re: VMC Mill Discussion

    Hi,
    i am the guy you see in the video but you are right next time i take more care ,..
    I have seen that machine i can not see any advantage to buy this ,..
    there are too many holes in that upright and i am not sure if they let me influence their design ,)-



  17. #77
    Gold Member LeeWay's Avatar
    Join Date
    Jun 2004
    Location
    United States
    Posts
    6618
    Downloads
    2
    Uploads
    0

    Default Re: VMC Mill Discussion

    That one is pretty cool. There are a few things I would change, but he has the Y motor in the right spot.

    Lee


  18. #78
    Gold Member LeeWay's Avatar
    Join Date
    Jun 2004
    Location
    United States
    Posts
    6618
    Downloads
    2
    Uploads
    0

    Default Re: VMC Mill Discussion

    I don't think they would let you make design changes.
    Looks like they have a few stacks of parts in the background.

    Lee


  19. #79
    Member
    Join Date
    Jul 2007
    Location
    Canada
    Posts
    1602
    Downloads
    5
    Uploads
    0

    Default Re: VMC Mill Discussion



  20. #80


Page 4 of 15 FirstFirst 123456714 ... LastLast

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
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

VMC Mill Discussion

VMC Mill Discussion