Re: [Emc-users] best diy 4th axis
A good trick for designing gears is to find a supplier of standard gears. Boston Gear is one and McMaster-Carr is another. Then you see on their web site they have CAD files for the gear. Just download the file. Then you can modify the hub or make thew face wider. Just about any kind of part os available on-line. I use Fusion360. It can import and export just about any kind of CAD file. On Wed, Apr 1, 2020 at 12:39 AM andrew beck wrote: > frank how do you design them? eg do you generate the gear > mathematically and what cad software do you use? > > regards > > Andrew > > On Wed, Apr 1, 2020 at 8:19 PM Frank Tkalcevic < > fr...@franksworkshop.com.au> > wrote: > > > > https://www.youtube.com/watch?v=Eds48L4cJjM > > > > In those designs, I've always been concerned that the moving part of the > > gear rubs against the outside lobes. This repair video shows a Sumitomo > > Cyclo which uses rolling pins on the outside, so minimal friction... > > > > https://youtu.be/H_oMVO_OTGs?t=157 > > > > (There's another video out there that shows an exploded view of this, > but I > > couldn't find it). > > > > I used this idea for some 3d printed hypocycloidal gearboxes for a robot > > arm, using bearings for the outside pins. It works, but the plastic is a > > bit squishy - on the TODO list is to cnc machine them out of aluminium, > > which shouldn't be hard as they are 2 1/2D parts. > > > > > > > > > > > > > > ___ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
Here is my idea of a rotary table drive system. I call it a wobble drive. I have not built one. This only exists in my CAD system. I sent this to Andy years ago. The drive he shows in the previous email in this thread was his answer to mine during an email conversation we had at the time. His would be much easier to build and rebuild. Mine had only sliding surfaces at the tooth interface. The advantage of mine (I think) would be there are more than 20 teeth in contact at all times. I have recently taken some time to modify my design and have rollers on the interface and still have the same amount of contact teeth. I have not animated my new design so this old file is all I have. My mind works rather slow. https://www.dropbox.com/s/zcew9qfv98kcgrn/testgear.AVI?dl=0 Please tell me if the link does not work. thanks Stuart On Wed, Apr 1, 2020 at 8:44 AM David Berndt wrote: > Heres a picture of the not very exciting square box I made that bolts > together and holds the spinea unit in the horizontal plane. Some of the > joints got scraped in and then the bottom was scraped for squareness with > the spinea flange. You can see my overhung fixture bar is already attached. > > https://photos.app.goo.gl/uPyBioiBrsJNtiVg6 > > Note the key use of gorilla tape on the outside of the ts200 and the last > round of notes from measurement/scraping still on the unit. Regular > duct-tape is not approved for cycloidal use. > > Here's what happens when you drive your drill chuck into that pipe > fixture > from the side. > > https://photos.app.goo.gl/zHxXurYgmY22msqb9 > > > -Dave > > > On Wed, 01 Apr 2020 03:05:52 -0400, John Dammeyer > > wrote: > > >> From: David Berndt [mailto:ber...@uberwin.com] > >> Alright, maybe i'm shooting myself in the foot here by inducing demand > >> and > >> I won't be able to get any cheap ebay units in future, but here goes... > >> > >> I bought a used spinea ts200 about a year ago and put a 750w servo on > >> the > >> back of it, built an enclosure and use it primarily as a fixturing > >> positioner. It's awesome for my needs. 169:1 ratio. Position holding > >> under > >> light milling (think 5hp or less is my experience, I don't have a 40hp > >> beast to test with) > > > > Any pictures? > > > > > > > > ___ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Addressee is the intended audience. If you are not the addressee then my consent is not given for you to read this email furthermore it is my wish you would close this without saving or reading, and cease and desist from saving or opening my private correspondence. Thank you for honoring my wish. ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
Heres a picture of the not very exciting square box I made that bolts together and holds the spinea unit in the horizontal plane. Some of the joints got scraped in and then the bottom was scraped for squareness with the spinea flange. You can see my overhung fixture bar is already attached. https://photos.app.goo.gl/uPyBioiBrsJNtiVg6 Note the key use of gorilla tape on the outside of the ts200 and the last round of notes from measurement/scraping still on the unit. Regular duct-tape is not approved for cycloidal use. Here's what happens when you drive your drill chuck into that pipe fixture from the side. https://photos.app.goo.gl/zHxXurYgmY22msqb9 -Dave On Wed, 01 Apr 2020 03:05:52 -0400, John Dammeyer wrote: From: David Berndt [mailto:ber...@uberwin.com] Alright, maybe i'm shooting myself in the foot here by inducing demand and I won't be able to get any cheap ebay units in future, but here goes... I bought a used spinea ts200 about a year ago and put a 750w servo on the back of it, built an enclosure and use it primarily as a fixturing positioner. It's awesome for my needs. 169:1 ratio. Position holding under light milling (think 5hp or less is my experience, I don't have a 40hp beast to test with) Any pictures? ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
>From memory, it's only the drive holes that need to be moved, rotated by 360/number of pins/2. I've uploaded a sample on my github page - https://github.com/ftkalcevic/Hypocycloid/tree/master/sample The 2 cams are 2 configurations of 1 part, each labelled (1,2) with a line which is meant to be parallel when assembled. The profile is a spline. If you can get the software to run (use visual studio community edition) it will generate the alibre components. -Original Message- From: andrew beck [mailto:andrewbeck0...@gmail.com] Sent: Wednesday, 1 April 2020 8:02 PM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] best diy 4th axis how did you make two offset profiles at 180 degrees apart. thats the bit I am having trouble working out. do you think you could share your alibre files? I have alibre and can also import into fusion 360 regards Andrew On Wed, Apr 1, 2020 at 9:55 PM Frank Tkalcevic wrote: > I got most of my information from this site... > > http://www.zincland.com/hypocycloid/ > > There's a python script to generate the profiles on that page > (http://www.zincland.com/hypocycloid/hypocycloid.zip) > > I wrote a C# program for Alibre Design to generate the parts - the code is > incomplete (https://github.com/ftkalcevic/Hypocycloid) > > > -Original Message- > From: andrew beck [mailto:andrewbeck0...@gmail.com] > Sent: Wednesday, 1 April 2020 6:36 PM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] best diy 4th axis > > frank how do you design them? eg do you generate the gear > mathematically and what cad software do you use? > > regards > > Andrew > > On Wed, Apr 1, 2020 at 8:19 PM Frank Tkalcevic < > fr...@franksworkshop.com.au> > wrote: > > > > https://www.youtube.com/watch?v=Eds48L4cJjM > > > > In those designs, I've always been concerned that the moving part of the > > gear rubs against the outside lobes. This repair video shows a Sumitomo > > Cyclo which uses rolling pins on the outside, so minimal friction... > > > > https://youtu.be/H_oMVO_OTGs?t=157 > > > > (There's another video out there that shows an exploded view of this, but > I > > couldn't find it). > > > > I used this idea for some 3d printed hypocycloidal gearboxes for a robot > > arm, using bearings for the outside pins. It works, but the plastic is a > > bit squishy - on the TODO list is to cnc machine them out of aluminium, > > which shouldn't be hard as they are 2 1/2D parts. > > > > > > > > > > > > > > ___ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
On Wed, 1 Apr 2020 at 10:49, andrew beck wrote: > It is just that I think the thin wave gear in harmonic drives is not strong > enough to hold up to heavy cutting forces. FHA-25 is rated at approx 200Nm. (it varies with the reduction ratio) Playing with FSWizard putting in a 16mm end mill at 4000 rpm in aluminium I am seeing 3kW of spindle power and 620N cutting force. So the FHA would be OK with those parameters and a 300mm radius workpiece. (600mm dia) I understand your concerns, but the numbers are reassuring. -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1912 ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
hey andy thanks for the link they look cool I already have a big harmonic drive the od is about 180 mm. and I have a matching servo motor to drive it. no crossed roller bearings but I could make it work easily. It is just that I think the thin wave gear in harmonic drives is not strong enough to hold up to heavy cutting forces. in comparison the cycloidal drives have 60 percent of the pins doing some of sort of work holding the thing rigid they look amazingly rigid and I think that is what new 5 axis machining centres use. anyway this is just a side line for now. I need to finish off the 3 axis mill stuff first and set up a qtpyvcp gui and work out the toolchanger. I will probably retrofit my cnc lathe also first while i am used to it then I will have a play with 4 and 5 axis I will be in touch with questions lol I need to learn HAL! regards Andrew regards Andrew On Wed, Apr 1, 2020 at 10:09 PM andy pugh wrote: > On Wed, 1 Apr 2020 at 04:07, andrew beck wrote: > > I have narrowed it down to either harmonic drives or Hypocycloidal gear > > boxes. > > > The FHA-25B harmonic drives are almost the perfect starting point as they > already contain a matched servo motor and very fancy cross-roller ring > bearing. > Specs here > > https://www.harmonicdrive.net/products/rotary-actuators/hollow-shaft-actuators/fha-c > But for easy retrofit use you want the -B version which has standard Hall > sensors and incremental encoder. > There is a relatively affordable on on eBay here: > https://www.ebay.co.uk/itm/153882616939 > I used one to make my 4th axis: > http://bodgesoc.blogspot.com/2017/05/harmonic.html > > Prior to that I had designed (possibly invented, I am not sure) this > easy-to-manufacture take on the cycloidal drive. > https://www.youtube.com/watch?v=VrvwlPxRhKU > > -- > atp > "A motorcycle is a bicycle with a pandemonium attachment and is designed > for the especial use of mechanical geniuses, daredevils and lunatics." > — George Fitch, Atlanta Constitution Newspaper, 1912 > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
On Wed, 1 Apr 2020 at 04:07, andrew beck wrote: I have narrowed it down to either harmonic drives or Hypocycloidal gear > boxes. The FHA-25B harmonic drives are almost the perfect starting point as they already contain a matched servo motor and very fancy cross-roller ring bearing. Specs here https://www.harmonicdrive.net/products/rotary-actuators/hollow-shaft-actuators/fha-c But for easy retrofit use you want the -B version which has standard Hall sensors and incremental encoder. There is a relatively affordable on on eBay here: https://www.ebay.co.uk/itm/153882616939 I used one to make my 4th axis: http://bodgesoc.blogspot.com/2017/05/harmonic.html Prior to that I had designed (possibly invented, I am not sure) this easy-to-manufacture take on the cycloidal drive. https://www.youtube.com/watch?v=VrvwlPxRhKU -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1912 ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
how did you make two offset profiles at 180 degrees apart. thats the bit I am having trouble working out. do you think you could share your alibre files? I have alibre and can also import into fusion 360 regards Andrew On Wed, Apr 1, 2020 at 9:55 PM Frank Tkalcevic wrote: > I got most of my information from this site... > > http://www.zincland.com/hypocycloid/ > > There's a python script to generate the profiles on that page > (http://www.zincland.com/hypocycloid/hypocycloid.zip) > > I wrote a C# program for Alibre Design to generate the parts - the code is > incomplete (https://github.com/ftkalcevic/Hypocycloid) > > > -Original Message- > From: andrew beck [mailto:andrewbeck0...@gmail.com] > Sent: Wednesday, 1 April 2020 6:36 PM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] best diy 4th axis > > frank how do you design them? eg do you generate the gear > mathematically and what cad software do you use? > > regards > > Andrew > > On Wed, Apr 1, 2020 at 8:19 PM Frank Tkalcevic < > fr...@franksworkshop.com.au> > wrote: > > > > https://www.youtube.com/watch?v=Eds48L4cJjM > > > > In those designs, I've always been concerned that the moving part of the > > gear rubs against the outside lobes. This repair video shows a Sumitomo > > Cyclo which uses rolling pins on the outside, so minimal friction... > > > > https://youtu.be/H_oMVO_OTGs?t=157 > > > > (There's another video out there that shows an exploded view of this, but > I > > couldn't find it). > > > > I used this idea for some 3d printed hypocycloidal gearboxes for a robot > > arm, using bearings for the outside pins. It works, but the plastic is a > > bit squishy - on the TODO list is to cnc machine them out of aluminium, > > which shouldn't be hard as they are 2 1/2D parts. > > > > > > > > > > > > > > ___ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
I got most of my information from this site... http://www.zincland.com/hypocycloid/ There's a python script to generate the profiles on that page (http://www.zincland.com/hypocycloid/hypocycloid.zip) I wrote a C# program for Alibre Design to generate the parts - the code is incomplete (https://github.com/ftkalcevic/Hypocycloid) -Original Message- From: andrew beck [mailto:andrewbeck0...@gmail.com] Sent: Wednesday, 1 April 2020 6:36 PM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] best diy 4th axis frank how do you design them? eg do you generate the gear mathematically and what cad software do you use? regards Andrew On Wed, Apr 1, 2020 at 8:19 PM Frank Tkalcevic wrote: > > https://www.youtube.com/watch?v=Eds48L4cJjM > > In those designs, I've always been concerned that the moving part of the > gear rubs against the outside lobes. This repair video shows a Sumitomo > Cyclo which uses rolling pins on the outside, so minimal friction... > > https://youtu.be/H_oMVO_OTGs?t=157 > > (There's another video out there that shows an exploded view of this, but I > couldn't find it). > > I used this idea for some 3d printed hypocycloidal gearboxes for a robot > arm, using bearings for the outside pins. It works, but the plastic is a > bit squishy - on the TODO list is to cnc machine them out of aluminium, > which shouldn't be hard as they are 2 1/2D parts. > > > > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
frank how do you design them? eg do you generate the gear mathematically and what cad software do you use? regards Andrew On Wed, Apr 1, 2020 at 8:19 PM Frank Tkalcevic wrote: > > https://www.youtube.com/watch?v=Eds48L4cJjM > > In those designs, I've always been concerned that the moving part of the > gear rubs against the outside lobes. This repair video shows a Sumitomo > Cyclo which uses rolling pins on the outside, so minimal friction... > > https://youtu.be/H_oMVO_OTGs?t=157 > > (There's another video out there that shows an exploded view of this, but I > couldn't find it). > > I used this idea for some 3d printed hypocycloidal gearboxes for a robot > arm, using bearings for the outside pins. It works, but the plastic is a > bit squishy - on the TODO list is to cnc machine them out of aluminium, > which shouldn't be hard as they are 2 1/2D parts. > > > > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
Hey david that looks like a cycloidal gearbox anyway lol that is what I wanted to make. If I can buy one sweet as no point re inventing the wheel regards Andrew On Wed, Apr 1, 2020 at 6:42 PM David Berndt wrote: > Alright, maybe i'm shooting myself in the foot here by inducing demand > and > I won't be able to get any cheap ebay units in future, but here goes... > > I bought a used spinea ts200 about a year ago and put a 750w servo on the > back of it, built an enclosure and use it primarily as a fixturing > positioner. It's awesome for my needs. 169:1 ratio. Position holding > under > light milling (think 5hp or less is my experience, I don't have a 40hp > beast to test with) > > I will say, from my limited 1 unit experience, the efficiency isn't great > if you want to get anywhere near top speed you'll have to swap the > grease, > or heat the unit, or just put a honking big servo on there. I have > trouble > getting over 10RPM without the servo running beyond it's continuous duty > zone. Maybe mine was filled with some sort of alternative grease in a > past > life, never opened it up to investigate. For positioning 10RPM is lots. > > I'm impressed with the milling stiffness. I've overhung a heavy walled 5" > square tube about 20" from the face of ths TS200 and use it as a 4 sided > fixture with no far end support and it still mills like a champ. I'm only > doing 2hp or less cuts in aluminum on that fixture, and I'm sure it'd be > better with a tailstock, but it's run for hundreds of hours making parts > without so far. The cross roller bearings in those units are quite > something. > > I haven't hooked up a brake of any sort, doesn't seem needed it for my > use > cases. > > One thing to maybe look out for if you care a lot about positioning is > the > these units have an angular transmission accuracy error/window that looks > something like +/- 17 arc seconds, differs for exact units, get specs > from > spinea for your model if you like. So if you care about resolutions > below > that, or lost motion then another solution, or a high resolution encoder > mounted on the output flange would be the way to go. I believe the strain > gauge units have a similar but different accuracy issue, perhaps software > compensation would even be possible? > > I'm also of the impression that the tilting stiffness and torsional > stiffness are significantly superior to the harmonic drives, but I could > be totally off there. > > -Dave > > > On Tue, 31 Mar 2020 23:03:11 -0400, andrew beck > > wrote: > > > Hey guys. > > > > I have been thinking about my 4th axis I am going to make. > > > > I have my cnc mill working now though there is still a bunch of work to > > get > > done. But I have been thinking about how I can make the best 4th axis > > and > > after that 5th axis. > > > > I have narrowed it down to either harmonic drives or Hypocycloidal gear > > boxes. > > > > I am thinking the hypocyloidal type looks the most rigid and best to make > > as it looks like the it would be very easy to make on a cnc mill and a > > harmonic drive relies on a thin strain wave gear that is not the > > strongest. I actually have a rather large one which I have been thinking > > about using but I would like to go with a the hypocycloidal design > > instead. > > > > all you guys out there with awesome cncs sitting in your sheds have you > > ever built one of these? I don't want to reinvent the wheel if I don't > > have to. And I am on the track to making my cnc a 5th axis when I get to > > it. First I will make the 4th axis and pump a bit of work through it and > > make some money lol. But 5 axis looks pretty fun and cool and I think it > > is finally doable for the pro diy person. > > > > I have all the toys like a surface grinder and lathes etc and of course > > the > > cnc mill. > > > > also don't mind spending money if needed as it is a business. > > > > here are some links to get the ideas flowing > > > > videos > > > > https://www.youtube.com/watch?v=Eds48L4cJjM > > > > fuson 360 scripts to generate the gear profile. > > > > > > https://github.com/mawildoer/cycloidal_generator/blob/master/README.md > > https://github.com/tapnair/Fusion360HypocycloidGear > > > > > > and just to show that it has been done before I say that the new Hass > > umc500 has cycloidal gearboxes in it so the design must be pretty good. > > > > > https://www.haascnc.com/machines/vertical-mills/universal-machine/models/umc-500.html > > > > > > regards > > > > Andrew > > > > ___ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
bari. I'm not sure how fast I want. just a reasonable speed for machining nothing fancy as of course its hard to make something fast and also accurate. they are like a catch 22 I would like to be able to use a 40 mm facemill on steel taking a 4 mm cut at 140 mm diameter if that help as a rough guide. I don't think the harmonic drive is up to that regards Andrew On Wed, Apr 1, 2020 at 6:06 PM Bari wrote: > How fast do you need it to move? > > How much torque do you require? > > > On 3/31/20 10:03 PM, andrew beck wrote: > > Hey guys. > > > > I have been thinking about my 4th axis I am going to make. > > > > I have my cnc mill working now though there is still a bunch of work to > get > > done. But I have been thinking about how I can make the best 4th axis > and > > after that 5th axis. > > > > I have narrowed it down to either harmonic drives or Hypocycloidal gear > > boxes. > > > > I am thinking the hypocyloidal type looks the most rigid and best to make > > as it looks like the it would be very easy to make on a cnc mill and a > > harmonic drive relies on a thin strain wave gear that is not the > > strongest. I actually have a rather large one which I have been thinking > > about using but I would like to go with a the hypocycloidal design > instead. > > > > all you guys out there with awesome cncs sitting in your sheds have you > > ever built one of these? I don't want to reinvent the wheel if I don't > > have to. And I am on the track to making my cnc a 5th axis when I get to > > it. First I will make the 4th axis and pump a bit of work through it and > > make some money lol. But 5 axis looks pretty fun and cool and I think it > > is finally doable for the pro diy person. > > > > I have all the toys like a surface grinder and lathes etc and of course > the > > cnc mill. > > > > also don't mind spending money if needed as it is a business. > > > > here are some links to get the ideas flowing > > > > videos > > > > https://www.youtube.com/watch?v=Eds48L4cJjM > > > > fuson 360 scripts to generate the gear profile. > > > > > > https://github.com/mawildoer/cycloidal_generator/blob/master/README.md > > https://github.com/tapnair/Fusion360HypocycloidGear > > > > > > and just to show that it has been done before I say that the new Hass > > umc500 has cycloidal gearboxes in it so the design must be pretty good. > > > > > https://www.haascnc.com/machines/vertical-mills/universal-machine/models/umc-500.html > > > > > > regards > > > > Andrew > > > > ___ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
John dammeyer I currently have a big harmonic drive but I think its not rigid enough. I have a 5 ton cnc mill with a 7.5 kw main motor and a full enclosure and i need a professional quality 4th axis hence looking for maximum accuracy and almost more importantly high rigidity and no backlash. I can always put a encoder on the end if we get crazy about it. Not sure what I actually need but it would be nice to machine something and then flip it 90 degrees and have a perfectly square. also I want to do simultaneous 4th axis machining so need a high rigidity without a brake though I will probably have a brake also. My dream is to offer 5 axis services here in new zealand as they are currently very expensive. its not like in america. a 5 axis machine is a big thing here. and If I can get one for e couple of thousand I will be stocked. I have some massive angular contact bearing (100 mm id 250 on) and they will handle any machining forces if the gearbox is ok. On Wed, Apr 1, 2020 at 5:46 PM John Dammeyer wrote: > > From: andrew beck [mailto:andrewbeck0...@gmail.com] > > > Hey guys. > > > > I have been thinking about my 4th axis I am going to make. > > > > I have my cnc mill working now though there is still a bunch of work to > get > > done. But I have been thinking about how I can make the best 4th axis > and > > after that 5th axis. > > > > I have narrowed it down to either harmonic drives or Hypocycloidal gear > > boxes. > > After Andy Pugh posted an Ebay link for a harmonic drive like his a couple > of years ago I jumped at it and bought it. I'm still way behind as I'm > just working on the crucible to hold enough aluminium to cast the holder. > Patterns are done and the STMBL runs it nicely sitting in the 3D printed > example of what I'll be machining. But no faceplate or chuck yet either. > > And does have his working with the STMBL drive. He's the best person to > report on harmonic drive for a 4th Axis. > > > > > I am thinking the hypocyloidal type looks the most rigid and best to make > > as it looks like the it would be very easy to make on a cnc mill and a > > harmonic drive relies on a thin strain wave gear that is not the > > strongest. I actually have a rather large one which I have been thinking > > about using but I would like to go with a the hypocycloidal design > instead. > > > > all you guys out there with awesome cncs sitting in your sheds have you > > ever built one of these? I don't want to reinvent the wheel if I don't > > have to. And I am on the track to making my cnc a 5th axis when I get to > > it. First I will make the 4th axis and pump a bit of work through it and > > make some money lol. But 5 axis looks pretty fun and cool and I think it > > is finally doable for the pro diy person. > > > > I have all the toys like a surface grinder and lathes etc and of course > the > > cnc mill. > > > > also don't mind spending money if needed as it is a business. > > > > here are some links to get the ideas flowing > > > > videos > > > > https://www.youtube.com/watch?v=Eds48L4cJjM > > > > fuson 360 scripts to generate the gear profile. > > > > > > https://github.com/mawildoer/cycloidal_generator/blob/master/README.md > > https://github.com/tapnair/Fusion360HypocycloidGear > > > > > > and just to show that it has been done before I say that the new Hass > > umc500 has cycloidal gearboxes in it so the design must be pretty good. > > > > > https://www.haascnc.com/machines/vertical-mills/universal-machine/models/umc-500.html > > > > > > regards > > > > Andrew > > > > ___ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
> https://www.youtube.com/watch?v=Eds48L4cJjM In those designs, I've always been concerned that the moving part of the gear rubs against the outside lobes. This repair video shows a Sumitomo Cyclo which uses rolling pins on the outside, so minimal friction... https://youtu.be/H_oMVO_OTGs?t=157 (There's another video out there that shows an exploded view of this, but I couldn't find it). I used this idea for some 3d printed hypocycloidal gearboxes for a robot arm, using bearings for the outside pins. It works, but the plastic is a bit squishy - on the TODO list is to cnc machine them out of aluminium, which shouldn't be hard as they are 2 1/2D parts. ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
> From: David Berndt [mailto:ber...@uberwin.com] > Alright, maybe i'm shooting myself in the foot here by inducing demand and > I won't be able to get any cheap ebay units in future, but here goes... > > I bought a used spinea ts200 about a year ago and put a 750w servo on the > back of it, built an enclosure and use it primarily as a fixturing > positioner. It's awesome for my needs. 169:1 ratio. Position holding under > light milling (think 5hp or less is my experience, I don't have a 40hp > beast to test with) Any pictures? ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
Alright, maybe i'm shooting myself in the foot here by inducing demand and I won't be able to get any cheap ebay units in future, but here goes... I bought a used spinea ts200 about a year ago and put a 750w servo on the back of it, built an enclosure and use it primarily as a fixturing positioner. It's awesome for my needs. 169:1 ratio. Position holding under light milling (think 5hp or less is my experience, I don't have a 40hp beast to test with) I will say, from my limited 1 unit experience, the efficiency isn't great if you want to get anywhere near top speed you'll have to swap the grease, or heat the unit, or just put a honking big servo on there. I have trouble getting over 10RPM without the servo running beyond it's continuous duty zone. Maybe mine was filled with some sort of alternative grease in a past life, never opened it up to investigate. For positioning 10RPM is lots. I'm impressed with the milling stiffness. I've overhung a heavy walled 5" square tube about 20" from the face of ths TS200 and use it as a 4 sided fixture with no far end support and it still mills like a champ. I'm only doing 2hp or less cuts in aluminum on that fixture, and I'm sure it'd be better with a tailstock, but it's run for hundreds of hours making parts without so far. The cross roller bearings in those units are quite something. I haven't hooked up a brake of any sort, doesn't seem needed it for my use cases. One thing to maybe look out for if you care a lot about positioning is the these units have an angular transmission accuracy error/window that looks something like +/- 17 arc seconds, differs for exact units, get specs from spinea for your model if you like. So if you care about resolutions below that, or lost motion then another solution, or a high resolution encoder mounted on the output flange would be the way to go. I believe the strain gauge units have a similar but different accuracy issue, perhaps software compensation would even be possible? I'm also of the impression that the tilting stiffness and torsional stiffness are significantly superior to the harmonic drives, but I could be totally off there. -Dave On Tue, 31 Mar 2020 23:03:11 -0400, andrew beck wrote: Hey guys. I have been thinking about my 4th axis I am going to make. I have my cnc mill working now though there is still a bunch of work to get done. But I have been thinking about how I can make the best 4th axis and after that 5th axis. I have narrowed it down to either harmonic drives or Hypocycloidal gear boxes. I am thinking the hypocyloidal type looks the most rigid and best to make as it looks like the it would be very easy to make on a cnc mill and a harmonic drive relies on a thin strain wave gear that is not the strongest. I actually have a rather large one which I have been thinking about using but I would like to go with a the hypocycloidal design instead. all you guys out there with awesome cncs sitting in your sheds have you ever built one of these? I don't want to reinvent the wheel if I don't have to. And I am on the track to making my cnc a 5th axis when I get to it. First I will make the 4th axis and pump a bit of work through it and make some money lol. But 5 axis looks pretty fun and cool and I think it is finally doable for the pro diy person. I have all the toys like a surface grinder and lathes etc and of course the cnc mill. also don't mind spending money if needed as it is a business. here are some links to get the ideas flowing videos https://www.youtube.com/watch?v=Eds48L4cJjM fuson 360 scripts to generate the gear profile. https://github.com/mawildoer/cycloidal_generator/blob/master/README.md https://github.com/tapnair/Fusion360HypocycloidGear and just to show that it has been done before I say that the new Hass umc500 has cycloidal gearboxes in it so the design must be pretty good. https://www.haascnc.com/machines/vertical-mills/universal-machine/models/umc-500.html regards Andrew ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
Sorry I left out: What accuracy is required? What repeatability is required? On 3/31/20 10:03 PM, andrew beck wrote: Hey guys. I have been thinking about my 4th axis I am going to make. I have my cnc mill working now though there is still a bunch of work to get done. But I have been thinking about how I can make the best 4th axis and after that 5th axis. I have narrowed it down to either harmonic drives or Hypocycloidal gear boxes. I am thinking the hypocyloidal type looks the most rigid and best to make as it looks like the it would be very easy to make on a cnc mill and a harmonic drive relies on a thin strain wave gear that is not the strongest. I actually have a rather large one which I have been thinking about using but I would like to go with a the hypocycloidal design instead. all you guys out there with awesome cncs sitting in your sheds have you ever built one of these? I don't want to reinvent the wheel if I don't have to. And I am on the track to making my cnc a 5th axis when I get to it. First I will make the 4th axis and pump a bit of work through it and make some money lol. But 5 axis looks pretty fun and cool and I think it is finally doable for the pro diy person. I have all the toys like a surface grinder and lathes etc and of course the cnc mill. also don't mind spending money if needed as it is a business. here are some links to get the ideas flowing videos https://www.youtube.com/watch?v=Eds48L4cJjM fuson 360 scripts to generate the gear profile. https://github.com/mawildoer/cycloidal_generator/blob/master/README.md https://github.com/tapnair/Fusion360HypocycloidGear and just to show that it has been done before I say that the new Hass umc500 has cycloidal gearboxes in it so the design must be pretty good. https://www.haascnc.com/machines/vertical-mills/universal-machine/models/umc-500.html regards Andrew ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
How fast do you need it to move? How much torque do you require? On 3/31/20 10:03 PM, andrew beck wrote: Hey guys. I have been thinking about my 4th axis I am going to make. I have my cnc mill working now though there is still a bunch of work to get done. But I have been thinking about how I can make the best 4th axis and after that 5th axis. I have narrowed it down to either harmonic drives or Hypocycloidal gear boxes. I am thinking the hypocyloidal type looks the most rigid and best to make as it looks like the it would be very easy to make on a cnc mill and a harmonic drive relies on a thin strain wave gear that is not the strongest. I actually have a rather large one which I have been thinking about using but I would like to go with a the hypocycloidal design instead. all you guys out there with awesome cncs sitting in your sheds have you ever built one of these? I don't want to reinvent the wheel if I don't have to. And I am on the track to making my cnc a 5th axis when I get to it. First I will make the 4th axis and pump a bit of work through it and make some money lol. But 5 axis looks pretty fun and cool and I think it is finally doable for the pro diy person. I have all the toys like a surface grinder and lathes etc and of course the cnc mill. also don't mind spending money if needed as it is a business. here are some links to get the ideas flowing videos https://www.youtube.com/watch?v=Eds48L4cJjM fuson 360 scripts to generate the gear profile. https://github.com/mawildoer/cycloidal_generator/blob/master/README.md https://github.com/tapnair/Fusion360HypocycloidGear and just to show that it has been done before I say that the new Hass umc500 has cycloidal gearboxes in it so the design must be pretty good. https://www.haascnc.com/machines/vertical-mills/universal-machine/models/umc-500.html regards Andrew ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] best diy 4th axis
> From: andrew beck [mailto:andrewbeck0...@gmail.com] > Hey guys. > > I have been thinking about my 4th axis I am going to make. > > I have my cnc mill working now though there is still a bunch of work to get > done. But I have been thinking about how I can make the best 4th axis and > after that 5th axis. > > I have narrowed it down to either harmonic drives or Hypocycloidal gear > boxes. After Andy Pugh posted an Ebay link for a harmonic drive like his a couple of years ago I jumped at it and bought it. I'm still way behind as I'm just working on the crucible to hold enough aluminium to cast the holder. Patterns are done and the STMBL runs it nicely sitting in the 3D printed example of what I'll be machining. But no faceplate or chuck yet either. And does have his working with the STMBL drive. He's the best person to report on harmonic drive for a 4th Axis. > > I am thinking the hypocyloidal type looks the most rigid and best to make > as it looks like the it would be very easy to make on a cnc mill and a > harmonic drive relies on a thin strain wave gear that is not the > strongest. I actually have a rather large one which I have been thinking > about using but I would like to go with a the hypocycloidal design instead. > > all you guys out there with awesome cncs sitting in your sheds have you > ever built one of these? I don't want to reinvent the wheel if I don't > have to. And I am on the track to making my cnc a 5th axis when I get to > it. First I will make the 4th axis and pump a bit of work through it and > make some money lol. But 5 axis looks pretty fun and cool and I think it > is finally doable for the pro diy person. > > I have all the toys like a surface grinder and lathes etc and of course the > cnc mill. > > also don't mind spending money if needed as it is a business. > > here are some links to get the ideas flowing > > videos > > https://www.youtube.com/watch?v=Eds48L4cJjM > > fuson 360 scripts to generate the gear profile. > > > https://github.com/mawildoer/cycloidal_generator/blob/master/README.md > https://github.com/tapnair/Fusion360HypocycloidGear > > > and just to show that it has been done before I say that the new Hass > umc500 has cycloidal gearboxes in it so the design must be pretty good. > > https://www.haascnc.com/machines/vertical-mills/universal-machine/models/umc-500.html > > > regards > > Andrew > > ___ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
