[ihavenofish]

On the spindle - is it using a frameless motor? Or belt/gear drive (looks too short for the motor to go on top)? BT30 is a good size for this machine, reminds me of those stupid-fast Brother machines with the dangerous looking toolchange

What are you thinking for the two rotary axis motors?

Jason

its a frameless motor in the spindle. its a stack thats only 1" long (2.5" total with windings and halls) so it fits nicely inside. drawbar release is also very compact - basically a motorcycle brake cyclinder. through spindle coolant might be nice to add as well, but im not sure yet how complicated that becomes with high speed rotary fluid unions and whatnot.

for the rotary axes, im not actually sure. theres room in the head for a worm gear, but i kinda want direct drive. the guys who do the spindle motor can do a pancake torque motor as well with a large bore. price on these motors seem to be a funtion of the amount of copper used, so they wont be super expensive compared to getting a precision no backlash gear setup. renishaw has a nice magnetic ring encoder as well which isnt very expensive.

id use THK crossed roller rings in both axes. 1 ring plus one stabilising radial tail bearing. your in the $4-5k range i think to make a rotary axis with water cooled frameless motor and crossed roller ring on this machine. again, not hobby priced, but this will definitely be the cheapest and most compact 5 axis box way machgine on the planet

[ihavenofish]

HSD also makes these guys if you have a need for ultra high speeds.
ES325 - H6161H0361
ES326 - H6161H0558

2kw and 4kw 50000rpm water cooled block. very small and can mount easily to the head of my machine. used HSK25 tooling, which is tiny, but you dont have many options at this speed.

ive never managed to get a price quote on it though. it think they are 5 figures though.

[Jason3]

What diameter is that frameless spindle motor? I agree, direct drive for the rotary axis would be ideal, as long as you can get enough torque. Should be possible. There was a comment (from Mike Everman in his Polar CNC thread) that the Renishaw magnetic encoders pole spacing was pretty large and shortwave errors would be high, though he also thought it would be good enough for machining. Hope so, I've bought one

That HSD spindle is pretty nice. You can check out IMT and Sycotec for similar high speed spindles - from memory the Sycotec 4064 comes in under $10K with drive. I'd like to see a slower spindle with more torque though - there's plenty at 20krpm +, and lots at <5,000 rpm but nothing much in a compact size from 10-15krpm. That's why your design interested me.

There's also pancake motors available from Granite Devices - pretty big admittedly, but maybe for the rotary table?

Regards,

Jason

[ihavenofish]

What diameter is that frameless spindle motor? I agree, direct drive for the rotary axis would be ideal, as long as you can get enough torque. Should be possible. There was a comment (from Mike Everman in his Polar CNC thread) that the Renishaw magnetic encoders pole spacing was pretty large and shortwave errors would be high, though he also thought it would be good enough for machining. Hope so, I've bought one

That HSD spindle is pretty nice. You can check out IMT and Sycotec for similar high speed spindles - from memory the Sycotec 4064 comes in under $10K with drive. I'd like to see a slower spindle with more torque though - there's plenty at 20krpm +, and lots at <5,000 rpm but nothing much in a compact size from 10-15krpm. That's why your design interested me.

There's also pancake motors available from Granite Devices - pretty big admittedly, but maybe for the rotary table?

Regards,

Jason

this is the encoder im looking at:
LM13RING - RLS d.o.o. rotary and linear motion sensors (encoders)
its a ring about 4" diametre. its basicaly the standard renishaw magnetic linear tape wrapped around a cylinder. this encoder was meant for my spindle actually, but at a higher res, it should be great for the tape. has up to 327000 counts per rev, which is about .0001" resolution at the outer edge of a 10" table. "good enough", haha. ill have to look for the price in my emails, i think it was in the $500 range for the ring and reader. its also a possibility to use the same tape for the linear axes. ive actually got one reader here,but the tape is attached to a slide and i dont think its removable.

the sycotec spindles are kavo right? they are nice, but nothing like the hsd blocks. the kavo are more like nsk. they are great got light duty hish speed and precision. i talked to nsk at the CMTS show a year ago, and they ran their 1.4kw atc spindle for me, it makes no noise and no vibrations. the drawback is its a propritary tool system - and $14000.

those HSD ones are more industrial with bigger bearings, encoders for rigid tapping and other fun features. they also have decent torque at lower speed ranges.

in any case, the motor in mine has a 1.6" bore, and a 3.5" outer diametre. its aparently a fairly universal size for electro spindles with lots of companies making them to spec. they can make the stator any length you want. i had a 2" stack speced with about 2 times the torque in the lower speeds, but limited to 8000rpm. there was also a 1" stack with 24000rpm, but ive abandoned that because it generates a ton of heat and needs ceramic bearings and fine balancing. i basically chatted with the engineer on the phone and he simulated motors based on the speeds and torques i wanted.

price on the 1" is $800 in one off, and $1200 for the 2" motor. volume prices were quite good too, but thats 50+ units. spindle inverters to run these are in the $500-$1000 range.

so with a water jacket, you have a spindle cartridge in the 110mm range, which is fairly universal for low power BT30 spindles. my head is 6" wide, so theres room for a standard bolt on flange, although my original design was a modular cartridge thingy, and this machine could take a block instead.

[ihavenofish]

that granite motor is cool. if it was about 1/3 the size it would work for the rotary axes.

for direct drive im thinking you also need a mechanical brake when its not doing coordinated motion. id mocked something up using a bicycle hydraulic disc brake before. that idea should work for this, but likely need a little more piston area.

[307startup]

in any case, the motor in mine has a 1.6" bore, and a 3.5" outer diametre. its aparently a fairly universal size for electro spindles with lots of companies making them to spec. they can make the stator any length you want. i had a 2" stack speced with about 2 times the torque in the lower speeds, but limited to 8000rpm. there was also a 1" stack with 24000rpm, but ive abandoned that because it generates a ton of heat and needs ceramic bearings and fine balancing. i basically chatted with the engineer on the phone and he simulated motors based on the speeds and torques i wanted.

price on the 1" is $800 in one off, and $1200 for the 2" motor. volume prices were quite good too, but thats 50+ units. spindle inverters to run these are in the $500-$1000 range.

so with a water jacket, you have a spindle cartridge in the 110mm range, which is fairly universal for low power BT30 spindles. my head is 6" wide, so theres room for a standard bolt on flange, although my original design was a modular cartridge thingy, and this machine could take a block instead.

So what would the total be if others wanted to buy a spindle like the one you're planning? Would it be a stock listing or custom order? Who would we go through to order it?

[ihavenofish]

So what would the total be if others wanted to buy a spindle like the one you're planning? Would it be a stock listing or custom order? Who would we go through to order it?

this is something i might make and sell, not sure yet. right now ths costs are pretty hig - about $5000 for a complete spindle head, and even than only if im doing 50 pieces at a time. then theres the tool changer, which is another $5000.

hard to say if that will sell.

[ihavenofish]

made some major alterations. column is built a little different, made motor mounts with integrated ball screw supports. also built the starret stand for the granite plate. the plate and stand from starret are $1600. theres probabaly lots of places that can make one for 1/2 that cost, since we really dont need the kind of precision starret offers.

[nomedia="http://www.youtube.com/watch?v=8U7XImUTrbc"]YouTube - travelling column cnc milling machine animation 4[/nomedia]

travel is bumped to 16x12x12. this was done without making the granite base any larger. having 16" in the x helps make better use of the swivel head. moving mass is still about the same at 850lbs on the X.

[ihavenofish]

few more tweaks to treamline construction, and now working out the enclosure.

its a bid frame that moves with the x axis. on each side there will be a vertical curtain. inside theres a cover plate for the Y that seals with the sides. at the bottom there will be another curtain that spans the y and z and seals with the sides. another curtain above the z. the problem now is getting/making a curtain that fits below the z axis. theres a bit of room, but not enough for the stock gortite models from what i can see.

[ihavenofish]

more covers. found there was actually room for a telescoping z cover, so i used that. the upper part of the z has the same cover, but is probably fine with a bellows. only have the y cover left to deal with, which is still going to be a roll up curtain mounted behind the angled skirt.

total width enclosed is now going to be about 40", which is not bad for 16" travel. depth will be 48" or so.

ill make a chip tray that slopes to the centre of the machine, so a chip auger can be located under the granite plate ejecting in the rear.

this things starting to look like a real vmc!

[ihavenofish]

almost done, yay!

[joeybagadonuts]

ihavenofish,

Are you going to build the machine or is this just a dream like your old renderings from years gone by?

JoeyB

[mactec54]

joeybagadonuts

Even if it is a dream, He has done a great job of what he is doing,This is what make the Zone such an interesting place

[ihavenofish]

moving dreams

[nomedia="http://www.youtube.com/watch?v=w58IxSXs6dQ"]YouTube - travelling column cnc milling machine animation 5[/nomedia]

i dont know if ill actually make this - its just design ideas. i think at this point they are good design ideas though, and it could be a great machine if it was made. thats about what you can say for 99% of the people on cnczone - lots of good ideas, not alot of time or money to complete things. at least computer animation is free, i got sick of buying parts for thousands of dollars then never using them.

so, after rendering the animation i realised that i didnt allocate any space fot the tool changer in the enclosure. not a big deal, but its going to need a 4-6" pop out drum cover on the left side. this is annoying because it ruins side by side stacking as you need access to mass load the tool changer. im trying to think of more creative ways to position the changer now.

[ihavenofish]

snuck in an interesting tool changer. since the head swivels, i just mounted a tray on the side of the cabinet. the spindle can swivel up, the tray will move down, and the spindle can grab a tool. its basically the same as a carousel in terms of function, but sideways and doesnt spin. it all moves well out of the way of chiips when not in use as well, which is quite nice. ill probabaly put a small cover over the tray to keep it safe when its retracted.

ive got 8 tool in this tray, but it could support 12 if you limited the diametre to 2" per tool. a machine with longer y travel can have more tools. you could also put a second tray on the other side of the machine to double the amount of tools available. the max tool length is limited to about 4.5" from the spindle nose because of the side window. i could make the machine an inch or 2 wider to accomodate longer drills and such - or just cut a hole in the window.

[ihavenofish]

getting pretty close to finished. sending another animation of this overnight showing the tool changer working.

[ihavenofish]

so, while thats rendering, i had some thoughts on how much this will cost.

in 5 axis form, fully built this machine is looking to be in the $50000 range. i dont know of any comparable 5 axis machine for that price. about the lowest youll find is taking a loaded $50,000 sharp 2412 and adding a small $25,000 trunion table. mine has the benifit of being alot more compact however. with 24" travel their machine is 73" wide and 95" tall, with 28" travel mine will be 54" wide and 72" tall. the sharp is of course a fair bit heavier, more rigid, and more powerful.

its all about the trade offs i guess.

im trying to figure out if this machine could work in some do it yourself fashion, but i think it will cost far too much for a hobbyist. the raw iron in the frame is worth over $2000 alone.

[TOTALLYRC]

Whether or not you build it I think it is a cool idea.
I really like the look of the swiveling head and the rotary table to get 5 axis.
If nothing else it is a reat way to get the tool storage from taking machine travel.

It would be cool to make a small version for doing lost wax machining for jewelry and other small work.

If I ever get my backyard foundry going I would love to give it a go.

Keep up the great work,


Mike

[ihavenofish]

thanks.
i think theres a lot of generally good ideas in this design that could be applied to lighter weight hobby machines if the high end model isnt viable to market. it would not be hard to reconfigure and have the frame cast and machined in china where a finished machined and scraped 800lb iron frame would run about $2500 ($3 a pound). throw in some quality taiwanese screws and teco servos, worm drive rotary axes, simpler spindle and fixed mid mounted tool rack and i think this machine could be done for $15000-$20000 give or take.

then we really would have the cheapest 5 axis box way machine around.

ive already gotton rid of the telescoping ways which will help my Y way cover problems. instead theres just a curtain above and below the spindle ram which will be boxed in to make a seal. this is basically how DMG does theirs, except they use steel roll up way covers. this makes thing cheaper too.

im also trying so see if i can mount a lathe spindle on the right side, with a 6 position turret that mounts into the spindle using the power drawbar allowing it to be changed out automatically. the spindle encoder will change the turret postions with a hydraulic brake locking it in place.

i have also been thinking about a 4x8" travel version for table top operation too, sitting on an 18x18 granite plate. im thinking this is cheap and easy to make as a functioning proof of concept for the big one.

anyhow, new animation will be done in an hour.

[ihavenofish]

[nomedia="http://www.youtube.com/watch?v=LUWllarwvg0"]YouTube - travelling column cnc milling machine animation 6[/nomedia]