584,808 active members*
5,362 visitors online*
Register for free
Login
IndustryArena Forum > MetalWorking Machines > Benchtop Machines > 7 Axis Swiss Mill-Turn (DIY)
Page 3 of 8 12345
Results 41 to 60 of 142
  1. #41
    Join Date
    Jun 2014
    Posts
    25

    Re: 7 Axis Swiss Mill-Turn (DIY)

    No the GIFs actually make this machine look smaller than it is. As it sits on the table, this thing is just under 6 feet long from left to right, 5 feet deep front to back, and just over 3 feet tall. The chuck is slightly over 6 inches in diameter for scale, the GIF of it facing is a 4 inch thick wall tube.
    The steppers are NEMA 24 size. The spindle motors are capable of more power than your power outlet is.

    BTW, the boxways and sliding/rotating parts of this machine are huge in comparison to everything in it's size class. I used a Hardinge HLV (very good toolroom lathe) to make some parts of this machine. The HLV has a 6 inch wide dovetail slide on its Z, and something like a 4 inch wide dovetail on the X. My machine has 6x10 and 8x10 boxway plates. Solid, thick slabs of aluminum don't bend by more than a few microns over the distances at play here. The posters on this thread are underestimating the size of this machine and its components because you're used to seeing all the gantry routers on this site that are made from thin walled 80/20 extrusions.

    The p5 bearings in the spindles have about 0.0002" runout, the next grade up (p4) has 0.0001" and those are the standard for full sized industrial machines.

    On the choice of acetal vs turcite, keep in mind that turcite is not commercially available unless you buy it in big sheets and it costs upward of 10 dollars per square inch. Boxway VMCs generally run for at least 5 years before wear in the boxways is noticeable, most machines aren't rebuilt until at least a decade of running production parts. The hard anodized layer of aluminum is a few thousandths thick and is more abrasion resistant than scraped cast iron. This is not a throwaway machine, it's designed to last a long time and be cheap to maintain if it ever needs to be.


    Almost forgot to address this part;
    "How does the lathe spindle transition between indexed/simultaneous 5 axis moves and turning speeds? What kind of gearboxes are you using for the rotary axes?"

    Right now the C axis (main spindle) uses a worm gear system on a pivot in addition to the timing belt and motor/encoder. The motor pulley is always connected to the spindle and 8192 count encoder gets the position along with index pulses for home. All fast operations, like drilling, turning, threading ect. use the main spindle motor to work. When the worm drive is engaged, the spindle gets a lot more torque and cannot be backdriven, at the cost of speed. This is for milling operations and heavier off-center ops. I suppose it could also be used for tapping with large taps. On the prototype this worm gear is engaged with a small lever, takes about a second to do. The production version will have something similar but with a small, cheap air cylinder and solenoid so it can be automated in addition to hand operable.
    The milling head B axis is a larger worm gear with two worms in opposition, they are driven by the same output and can't be disengaged. The production version will have a shot-pin plate on an air cylinder to help with initial alignment and also give a locking mechanism for really heavy cuts and extra rigidity when using longer tool holders that reach further from the B axis centerline.

  2. #42
    Join Date
    Oct 2017
    Posts
    49
    Any updates? Would love to see a full video of making a part.

  3. #43
    Join Date
    Jun 2014
    Posts
    25

    Re: 7 Axis Swiss Mill-Turn (DIY)

    I'm actually a few hundred miles from the machine right now, and I will be for a while. I did a couple full part videos for the first prototype but they didn't get many views, I attributed that to the short attention span of youtube viewers but I still have the original content from a couple years ago so I may re-edit and re-upload those videos on the new channel. For now, here are some clips of it making sample parts. This style of editing is meant to cram as much stuff as possible into a short video, showing only the more interesting stuff. A video that covers the entire process from drawing the part to programming the Gcode to setting up tools to machining to inspection would take much longer, I hate to say it but there isn't much incentive to make videos like that since attention spans drop off exponentially with viewing time, and then the video gets pushed into obscurity by Youtube's algorithms.




    The GIF below shows side milling a (cast iron?) bar with a fairly large depth of cut. If I had a boring bar I would have filmed what you asked a few posts back, but so far this is the heaviest cut I've taken on this machine.


  4. #44
    Join Date
    Jul 2003
    Posts
    586

    Re: 7 Axis Swiss Mill-Turn (DIY)

    I love it. Keep it coming.

  5. #45
    Join Date
    Jul 2003
    Posts
    586

    Re: 7 Axis Swiss Mill-Turn (DIY)

    where are the videos. how did I miss them?

  6. #46
    Join Date
    Feb 2018
    Posts
    92

    Re: 7 Axis Swiss Mill-Turn (DIY)

    I did see one of the pocketnc units, in fact I was considering buying one. Once I saw the results in person, I was happy I didn't. Despite all sorts of pretty videos giving the impression of it making parts with ease, its rapids probably couldn't catch a snail across the table and all of their demos to show the accuracy were done with no load. It was lucky to cut a circular piece of balsa wood.

    While the videos shown are great eye-candy for this machine, they really remind me of the pocketnc advertising. I wish the OP could demonstrate specifics, like taking a substantial circular cut from some 6061 plate, then showing closeup photos of the results as well as measurements to show the dimensional accuracy of the finished part. Many of the youtube videos I see will show how they do something and follow up with an indicator, mic or whatever to demonstrate their results. If it can be demonstrated that it will cut x IPM through material Y using this cutter at that RPM, it should be specified. I'm not saying that I couldn't be made into a believer, but I remain unconvinced that the physics of this design / materials will stand up to what is promised.

  7. #47
    Join Date
    Feb 2015
    Posts
    31

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Quote Originally Posted by Generic Default
    BTW, the boxways and sliding/rotating parts of this machine are huge in comparison to everything in it's size class. I used a Hardinge HLV (very good toolroom lathe) to make some parts of this machine. The HLV has a 6 inch wide dovetail slide on its Z, and something like a 4 inch wide dovetail on the X. My machine has 6x10 and 8x10 boxway plates. Solid, thick slabs of aluminum don't bend by more than a few microns over the distances at play here. The posters on this thread are underestimating the size of this machine and its components because you're used to seeing all the gantry routers on this site that are made from thin walled 80/20 extrusions.
    The irony is that the HLV is a very light lathe (although quite heavy for it's size, in order to maximize precision), and weighs about 1,700 pounds (and in good condition costs an order of magnitude more than you're stated price range -- used!). I find it hard to believe your machine is in the same capability class as the HLV -- I'm more than happy for you to try to prove it though.

    Bending is a result of force, your plate thickness is only a factor in reducing it's effect.

    These kind of statements make me, and will make anyone else with a machining or engineering background, leery. They are not statements of fact nor are they statements someone with an understanding of the underlying physics would make.

    The p5 bearings in the spindles have about 0.0002" runout, the next grade up (p4) has 0.0001" and those are the standard for full sized industrial machines.
    Bearing runout is only one factor in total spindle runout (and not the most important or difficult one to achieve, for that matter). As I've said before, getting quality ground spindles in your price range is not believable.

    On the choice of acetal vs turcite, keep in mind that turcite is not commercially available unless you buy it in big sheets and it costs upward of 10 dollars per square inch. Boxway VMCs generally run for at least 5 years before wear in the boxways is noticeable, most machines aren't rebuilt until at least a decade of running production parts.
    Other than the Turcite costs (which you're quoting at a non-volume price), you're absolutely right.

    The hard anodized layer of aluminum is a few thousandths thick and is more abrasion resistant than scraped cast iron.
    Do you have data to back this up? I find it hard to believe, and cast iron has the benefit of much better post-machining and thermal stability, both of which are invaluable. Regardless, making claims about how your system is better than the serious machine builders should be supported by data.

    Also, note that Turcite/Rulon/etc. scraped surfaces split the load between the polymer and the metal and that the scraping allows proper oil lubrication. The setup you have doesn't do any of this, and as such you're going to see rapid wear in the acetal pads.

    This is not a throwaway machine, it's designed to last a long time and be cheap to maintain if it ever needs to be.
    The problem is choosing cheap, easy to maintain components over more expensive but longer lasting ones.

    Quote Originally Posted by hackish
    I did see one of the pocketnc units, in fact I was considering buying one. Once I saw the results in person, I was happy I didn't. Despite all sorts of pretty videos giving the impression of it making parts with ease, its rapids probably couldn't catch a snail across the table and all of their demos to show the accuracy were done with no load. It was lucky to cut a circular piece of balsa wood.

    While the videos shown are great eye-candy for this machine, they really remind me of the pocketnc advertising. I wish the OP could demonstrate specifics, like taking a substantial circular cut from some 6061 plate, then showing closeup photos of the results as well as measurements to show the dimensional accuracy of the finished part. Many of the youtube videos I see will show how they do something and follow up with an indicator, mic or whatever to demonstrate their results. If it can be demonstrated that it will cut x IPM through material Y using this cutter at that RPM, it should be specified. I'm not saying that I couldn't be made into a believer, but I remain unconvinced that the physics of this design / materials will stand up to what is promised.
    Excellent breakdown of how I see the situation as well. I'm concerned that the comparison to pocketnc may be apt.

    So far I see a 1/2" cutter taking a 0.050" cut at unknown feed, without an information about tolerances held on the part. It may be that there's convincing data there, but it's certainly not being shared.

  8. #48
    Join Date
    Apr 2005
    Posts
    419

    Re: 7 Axis Swiss Mill-Turn (DIY)

    I'm not sure the PocketNC comparisons are fair. In video, and even in their demo photos, the PocketNC was clearly incapable of cutting aluminum. The surface finish and sound were just disgusting.

    All the samples of the machine shown so far look fine and are certainly believable given its mass.

  9. #49
    Join Date
    Feb 2015
    Posts
    31

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Quote Originally Posted by 691175002 View Post
    I'm not sure the PocketNC comparisons are fair. In video, and even in their demo photos, the PocketNC was clearly incapable of cutting aluminum. The surface finish and sound were just disgusting.

    All the samples of the machine shown so far look fine and are certainly believable given its mass.
    I'm not sure that was the comparison hackish was looking at.

    I would have said the major setbacks were limited capability compared to price, poor design decisions regarding both quality of components and machine design, and limited understanding of the market it was competing in. Also note that it retails around $4k, yet somehow this is supposed to retail starting around $2k?

    Quote Originally Posted by Generic Default
    The initial Kickstarter will have a simple 3 axis variant available for under 2k with rigid tapping standard.
    As far as the PocketNC goes, my understanding is that there are people doing jewelry (lost-wax and -plastic casting) who find it useful and cheaper than its competitors though.

    Regardless of who is marketing or making the machine, there is limited value in statements without data and wild claims about price, quality, accuracy, or any other capability.

  10. #50
    Join Date
    Jun 2014
    Posts
    25

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Pariel,

    In my last post I attached a GIF of it cutting cast iron, although I don't know the exact grade (it wasn't a soft grade though). That was just over 25 inches per minute, axial depth of cut 0.6", radial depth of cut 0.07". Since it was flattening a round bar we can't use the normal width*depth*speed method to find material removal rate, but I drew it in CAD and checked volume calculations before and after the cut. Right around 0.9 cubic inches per minute of MMR, which corresponds to a ~400 watt cut.

    I know 400 watts is tiny compared to "real" machines with 30 horsepower spindles, but when you consider that it's built to make fairly small parts (limited by 6 inch chuck) a few hundred watts can get a workpiece done in a matter of minutes. This machine obviously doesn't stack up against the big ones in terms of linear speed, power, work envelope, ect. but it has everything needed to make parts without a bunch of part flipping and re-clamping for each side. It was never intended to be a workhorse production machine for people making huge steel parts. For small parts that fit in the chuck, it's pretty damn good. The production version will handle 2 horsepower cuts.

    Since you're a numbers kinda guy, I'll do some FEA to show you how tiny and insignificant the deflection values are for parts of the machine structure, in both aluminum and cast iron.



    Using cast iron rather than aluminum for the machine structure would nearly double the structural rigidity, and give it better damping properties. Believe me I considered making this out of CI, specifically dura-bar and versa-bar, which are the really nice continuous cast types that machine well and don't have hard spots. I didn't have the equipment to lift parts that heavy, as the base alone would weigh around 270 pounds. Also, nobody seems to stock or sell it, or even list prices for that matter. Aluminum can be face milled or fly cut in very thin finishing passes to accurate final dimensions, so there's no need to grind it or scrape it. The anodized layer is around 65 rockwell C, much harder than hardened cast iron. In boxway VMCs, the Turcite (metal powder filled PTFE) is bonded to the machine structure and generally the hand scraped cast iron machine table slides against it. The guys who rebuild these machines say that the iron surface barely wears at all, it's the Turcite strips that get eaten up over the years. Still longer lasting than the metal-on-metal boxways that were used up through the 1970s.

    The low price of this machine is due to a lack of expensive components, mainly ballscrews, ballnuts, and linear rails/trucks. PocketNC came out before I even designed this mill turn. I know they put a large percentage of their machine build cost into the rails and the spindle. They mill all the aluminum with a Haas mini-mill in their garage. Nema 17 steppers for 8mm screws. It looks like a really cool machine for jewelers, but I wanted something for bigger metal parts.

  11. #51
    Join Date
    Aug 2016
    Posts
    132

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Alro sells Dura-bar. They have an online store you can check prices with. A 4 1/4" x 4 1/4" x 4 ft bar would be $485.97.

  12. #52
    Join Date
    Feb 2018
    Posts
    92

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Quote Originally Posted by 691175002 View Post
    I'm not sure the PocketNC comparisons are fair. In video, and even in their demo photos, the PocketNC was clearly incapable of cutting aluminum. The surface finish and sound were just disgusting.

    All the samples of the machine shown so far look fine and are certainly believable given its mass.
    You missed the point entirely. It was not at all about comparing PocketNC to this machine. It was about using eye candy instead of solid examples and numbers to sell the product. I try to remain positive and optimistic with this product, since it is obviously the result of someone's 1000+h spent designing and fabricating, as well as no doubt a good chunk of money. My experience has been that using a machine often shows its limits rather than trying to run theoretical simulations. Give us some realistic numbers with photos to show where the typical performance envelope lies. I can imagine that an Al machine could possibly exhibit some interesting resonation.

  13. #53
    Join Date
    Jun 2011
    Posts
    692

    Re: 7 Axis Swiss Mill-Turn (DIY)

    PocketNC raised $350k with their video/story.. So eye candy seems to work..
    If this machine can do what it's claimed it can do and he can deliver for anywhere near the prices he's promising, some more technical info would be very useful for the more serious types (like on here,) who don't have $2-5k to burn on a toy but wouldn't mind spending it on something with some real capabilities though.

  14. #54
    Join Date
    May 2015
    Posts
    1422

    Re: 7 Axis Swiss Mill-Turn (DIY)

    How did I not see this thread before, GD? Your project was the only reason I was still hanging around the SeeMe forums and now I can keep up to date here

    I've still to wade through the rest of the thread (just saw the first post) but if I can help by casting an eye over the kickstarter test page or with anything else, let me know.

    Cheers

    dharmic aka capt starfish

  15. #55
    Join Date
    Jun 2014
    Posts
    25

    Re: 7 Axis Swiss Mill-Turn (DIY)

    To address the last few comments...

    That pricing for Dura-bar seems outrageous. The shipping would probably bring it to ~700 dollars. Just for the machine base! I spent just over 200 dollars for the aluminum one, and that was at retail prices of ~3 dollars per lb.

    Hackish also mentioned resonance with aluminum; the version 1 prototype used a 3x3 square tube as the base with the boxway bars bolted on top of it. It did have resonance problems, not so much when cutting metal but when the machine parts were sliding at certain speeds. The V1 prototype used a very different wear pad arrangement, and the sliding made the base ring at a low frequency. This is why I built the V2 prototype with a 4 inch solid square bar base. It eliminated the resonance problems completely for both cutting operations and traversing, and added a ton of rigidity and dimensional stability to the whole thing.

    Skrubol, I have a few tech specs charts on the kickstarter page, once the project launches you will have all the info you want laid out. At this point I have the launch video done but I'm stalling until I get the last few costs nailed down. The recent tariffs with this administration make it very difficult to estimate metal prices several months in advance, and considering the cost of aluminum and steel are ~50% of the cost of my machine(s), I can't gamble with it by taking a bunch of pre-orders at an assumed price only to see the cost of production go up 30% or whatever.



    For now, I'll put a few more build pictures up on this thread. From top to bottom:
    1) Y axis slab with B axis bearing seats in the VMC. It's 10 x 10 x 2 inches, the bearing holes in the middle are 100mm in diameter.
    2) The turret block in the VMC.3 x 8 x 11 inch stock, same 100mm bearing pockets.
    3) Side view of the main lathe spindle with the face plate and 6 inch chuck bolted on. The left half of it is 65mm in diameter for a light press fit into 7013 angular contact bearings. The round keys at the left are for torque input.
    4) Same spindle, showing the faceplate. This face plate design allows all standard 4, 5, and 6 inch chucks and collet noses to be attached. I might make a custom faceplate with an integrated 5 axis pyramid vise, wouldn't cost much to do.
    5) Turning the turret shaft. The local metal place accidentally sold me a bar of 304 stainless rather than 1018 like I wanted, so I got 90$ of stainless for 30$. But it broke some taps and drills making it, and in the end the locknut seized permanently onto the threads before final assembly and I had to redo the entire shaft. Wasted a week and a lot of money.






  16. #56
    Join Date
    Dec 2006
    Posts
    31

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Very cool...I like it!

  17. #57

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Just seen this thread. Very nice looking lathe/mill. Certainly will be useful for certain applications/companies, not really for production companies in my opinion. Probably toolroom or prototyping, R&D workshops would be the best fit probably, or the hobby market, where machining the part at speed isn't an issue.
    It's a lovely looking setup. Does it have a stand? If not then adding a stand would also increase the weight as well as make it more versatile.
    You did an amazing job for 2 grand. Did you use C3 ballscrews?

  18. #58
    Join Date
    Jun 2014
    Posts
    25

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Does it have a stand? If not then adding a stand would also increase the weight as well as make it more versatile.
    Did you use C3 ballscrews?
    Doesn't come with a stand, it just sits on any big table or desk. A stand won't actually provide any rigidity unless it's a part of the machine structure.As shown in this thread, I just set the machine on top of two interlocking foam pads that I used to use for my 3d printers. Since the SwissMak base is literally just a 4x4 solid metal bar, it doesn't bend more than a few microns over the span of its length. The foam pads prevent vibration transfer to the table underneath.

    It doesn't use ballscrews at all, as ballscrews die as soon as any tiny chips or dust or whatever gets in. This machine uses leadscrews and long nuts to get backlash to a few tenths.



    Also, in other news, we're launching the Kickstarter April 20th 2018 (two days from now). If it fizzles out from a lack of exposure we'll just launch again. Here's the launch video;


  19. #59

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Quote Originally Posted by Generic Default View Post
    Doesn't come with a stand, it just sits on any big table or desk. A stand won't actually provide any rigidity unless it's a part of the machine structure.As shown in this thread, I just set the machine on top of two interlocking foam pads that I used to use for my 3d printers. Since the SwissMak base is literally just a 4x4 solid metal bar, it doesn't bend more than a few microns over the span of its length. The foam pads prevent vibration transfer to the table underneath.

    It doesn't use ballscrews at all, as ballscrews die as soon as any tiny chips or dust or whatever gets in. This machine uses leadscrews and long nuts to get backlash to a few tenths.



    Also, in other news, we're launching the Kickstarter April 20th 2018 (two days from now). If it fizzles out from a lack of exposure we'll just launch again. Here's the launch video;

    I agree about the stand, unless it's connected it wouldn't be much use.
    Leadscrews eh? I did wonder about swarf getting in the Ballscrews people keep posting videos of, perhaps dust from wood has less of an effect than metal. Don't know too much about them, doesn't the same problem apply to an exposed Leadscrew?
    I'm looking at designing my own mill so looking at all the options.
    Engineer - Artist - Writer

  20. #60
    Join Date
    Jun 2011
    Posts
    692

    Re: 7 Axis Swiss Mill-Turn (DIY)

    Quote Originally Posted by Krispee View Post
    Leadscrews eh? I did wonder about swarf getting in the Ballscrews people keep posting videos of, perhaps dust from wood has less of an effect than metal. Don't know too much about them, doesn't the same problem apply to an exposed Leadscrew?
    I'm looking at designing my own mill so looking at all the options.
    I think lead screws are a little more tolerant of chips getting in them because they're self-wiping. The nut slides along the screw and therefore pushes most large debris off. Ball screws usually have some sort of wiper on them, but it's usually fairly soft and probably wears out eventually, but the balls roll over the screw, so if there's debris that makes it past the wiper, the balls may roll right over it.
    Plus lead screws require more frequent lubrication, and putting oil in the nut will tend to push some of the stuff out.

Page 3 of 8 12345

Similar Threads

  1. Replies: 0
    Last Post: 04-01-2016, 07:55 PM
  2. Replies: 0
    Last Post: 04-01-2016, 07:52 PM
  3. Mill/Turn Y axis Instead of C
    By FlorinMBV in forum FeatureCAM CAD/CAM
    Replies: 2
    Last Post: 03-29-2016, 07:07 AM
  4. Replies: 15
    Last Post: 04-14-2011, 05:33 PM
  5. Swiss turn material
    By scook179351 in forum CNC Swiss Screw Machines
    Replies: 8
    Last Post: 05-11-2008, 06:37 AM

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
  •