Thread: where to start?

Page 4 of 5 FirstFirst ... 2345 LastLast
  1. #31
    Quote Originally Posted by Jonathan View Post
    What about using 16mm ballscrews (RM1610) and rotating ballnuts. You save buying the end bearings, and the angular contact bearings aren't so expensive as they're not so big as with 25mm screws. Should get a very decent feedrate. Just a thought...
    Yes if it was me I'd be seriously considering it. . . I'm a massive ballscrew fan has you know.!

    But I was giving easy options that could be bought off the shelf at sensible money. Rotating nut is OK if you have the equipment IE: Mill etc and knowledge to make one. Don't think neil has the equipment.? The knowledge could be gained but probably daunting for someone new and was aiming my suggestions with this newness in mind.!

    Think I'd also go with a higher 20mm pitch if being used solely for cutting woods n plastics so the cutting feed is in the meat of the motors torque. Reason being think for a machine this size nema34 would be needed and they don't spin as fast as 23's so with 10mm pitch then gearing would be needed to bring the speeds/feeds up and that will affect the torque.
    You have to think when cutting wood you need high feeds and deep DOC for best performance and even faster for plastics, so better to put the right pitch screws on in the first place than use gearing IMO. . . . . Back to horse's for course's. .:confused:

  2. #32
    Quote Originally Posted by trounce View Post
    I hate asking so many questions but this is so alien to me and quite bamboozling at times
    [/URL]
    No you should ask no matter how alien or embarrassed you feel asking. We have all been where you are today so know exactly how it feels. . . .Ask away then ask some more.

  3. #33
    Quote Originally Posted by JAZZCNC View Post
    But I was giving easy options that could be bought off the shelf at sensible money
    Welcome to buy one from my shelf...

    Quote Originally Posted by JAZZCNC View Post
    Think I'd also go with a higher 20mm pitch if being used solely for cutting woods n plastics
    Same, but you couldn't get 20mm pitch from eBay seller last time I checked. I would have done the same otherwise.
    Thinking about it since end machining isn't strictly neccecary with a rotating ballnut setup (helps, but I reckon you could do it without by making mounts that clamp the screws, rather like the mounts for round rails) you could buy the 20mm pitch ballscrew from Zapp without spending 7.5*10^99 on end machining. This one:

    http://www.zappautomation.co.uk/r161...121c620028629f

    or

    http://www.zappautomation.co.uk/r202...121c620028629f


    Oh, just noticed the ball-nuts are a bit pricey ... shame.
    I'd love to try it with some 20mm pitch screws and big motors / servos and see just how fast you can get with rotating nuts.

  4. #34
    Quote Originally Posted by Jonathan View Post
    I'd love to try it with some 20mm pitch screws and big motors / servos and see just how fast you can get with rotating nuts.
    Jonathan Don't understand the facination with speed.? . . . It's only any good upto a point then it's a waste. It's like very high rapid speeds there only of any use on certain types of jobs but in the main there useless and come at too costly a price.! . . . . Impressive, great for bragging right's but mostly pointless.

    To be of any real use and cutt at high feed rates you need fast high horse power spindles, expensize tooling and a very ridged machines which can handle the force's involved

    The cutter and material specs mostly dictate feeds anyway so IMO most high pitch screws are more than enough when it comes to DIY cnc and even small production use.

  5. #35
    I know up to a point extra speed gives diminishing returns. Sometimes it just compensates for bad Gcode with lots of G0's. It would be good if you wanted to add a laser ... though of course there's easier ways to move just a laser.

  6. #36
    Quote Originally Posted by trounce View Post

    This will just be for the bed section and not the legs etc as I'm aiming to put some more pennies away to be able afford alluminium profile for the bottom section or at least some other much lighter alternative that can be unbolted and taken apart.

    I think I'm also gonna have to find a way to make the bed come apart aswell or at least some of the supports because If I ever have to move it all I'll need a crane :rofl:
    [/URL]
    Hi Neil,

    Here's a bit of outside the box thinking to give your grey matter a workout.? . . . If your tight on space why not make a wall mounted router, a bit like a panel saw.:surprised:
    There's no rules that says you have to work flat.! The advantages are meny with very few if any disadvantages.? . . Let me expand on the minus's & plus's.

    99% of the time you'll clamp material to the bed, even offcuts you'll clamp so they dont get pulled/pushed into cutters path. So no real disadvantage being vertical or inclined.
    The plus's being gravity will help greatly with chip clearance and all the crap falling into a catch tray or vac funnel you could build into the bottom.

    If mounted so the gantry moves left to right or long axis length ways then the only Axis fighting gravity is the Z axis moving along the Yaxis and this is no big deal because your not lifting/lowering a real heavy mass so with the correct size motor/gearing it won't be a problem.
    Though depending how or what you use for linear motion you may need to park it at the bottom when motors are disengaged to stop backdrive. If you use R&P with a worm drive then it wont back drive.!

    The foot print on the shop floor Space is a massive saving (Obviosly you'll need a free wall long enough).
    Being mounted on the wall you wont need quite as much material because you dont need to build all the frame work to bring it upto a working height. . . . Basicly it would be like building it to sit directly on the floor, with just a small frame to give a slight incline off the wall.
    Also very easy to build wheels onto the frame work base for moving, would basicly go thru most workshop single door ways.

    Being wall mounted and only standing off the wall a few feet it will basicly take the space of a large wardrobe.! Being like a wardrobe it thens makes it very easy to build a simple frame around it with 2 narrow sides(Or 1 if placed in corner) and folding doors on the front.? . . . Now it's a cabinet router with all the dust and crap contained leaving a nice clean workshop.! (Like mine.:rofl:) The important computer and control box could be mounted outside on one of the end panels for easy access.

    So few disadvantages but several very usefull and easily implimented Advantages.

    My next Mill will be built on this principle but with a twist I'll keep for another day. .:naughty:

    Certainly food for thought.!

    Edit: I've often thought to chop the legs off my machine and hang it off the wall and one day when I've nothing to do it may very well happen. . . Winters coming.:naughty:
    Last edited by JAZZCNC; 09-09-2011 at 05:48 PM.

  7. #37
    I was originally going to mount my router to the roof, so at a bit of an odd angle. This was due to space. In the end I did mount it on the floor as I persuaded my Dad there was enough space.

  8. #38
    Quote Originally Posted by Jonathan View Post
    I was originally going to mount my router to the roof, so at a bit of an odd angle. This was due to space. In the end I did mount it on the floor as I persuaded my Dad there was enough space.
    Nah would give ya neck ache and a 10mm single flute cutter in the eye hurts like shit. .:tup:

  9. #39
    all I'm going to say is hee hee hee

    James

  10. #40
    The space issue is really only a problem whilst its being built, I have a galvanised shed in the garden that's 10' x 12' so as long as it fits in there I'll be ok. My main concern was actually moving it because I'll be building it in a garage that I rent next to my house.
    I've designed the bed so that a large chunk of the inner supports can be unbolted and removed to make it much lighter when moving it, though I'm not sure if all these supports are really needed.

    The outer grey sections will be welded together and the inner sections will be bolted to the frame, though I may get rid of the centre bolts and just have a fully welded cross shape in each inner section.
    Outer is 60 x 60 x 3 and the inner pieces are 60 x 30 x 3.
    This is my first attempt using google sketch up and I'm pretty chuffed with the outcome :tup:

    If you could let me know if it looks ok or if its overkill with all the inner sections?
    Cheers
    Neill

    Click image for larger version. 

Name:	bed.jpg 
Views:	114 
Size:	290.9 KB 
ID:	4498

Page 4 of 5 FirstFirst ... 2345 LastLast

Similar Threads

  1. Where to start?
    By Inquisitor in forum Gantry/Router Machines & Building
    Replies: 7
    Last Post: 27-11-2012, 02:35 PM
  2. where to start
    By martin54 in forum Gantry/Router Machines & Building
    Replies: 16
    Last Post: 22-09-2012, 11:29 AM
  3. is this 2.5d where do i start? help please if you can
    By h4ppy-chris in forum General Discussion
    Replies: 4
    Last Post: 29-03-2011, 12:21 PM
  4. NEW MEMBER: Were do I start?!
    By tonygagey in forum New Member Introductions
    Replies: 4
    Last Post: 07-08-2010, 07:55 PM
  5. Where to start?
    By ricey3 in forum Computer Software
    Replies: 10
    Last Post: 25-10-2009, 08:01 PM

Bookmarks

Posting Permissions

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