[CNCMachineplans]

Thanks Hoss
Your experience is very valued round here.

[bladehunter]

I'm running 570's on all 3 axis, and it's kind of scarey how fast these motors will move. And this is with a 150mm vertex vice on the table.

Big thanks to Hoss for his recommendations for the electronics.

Are you in Oz CNC ?

[CNCMachineplans]

Hi Bladehunter.
Yes I am in oz,
Chris

[arizonavideo]

With a 5 TPI ball screw the 570oz stepper will lift about 850 pounds.

The mill is less than 300 so you can turn it up side down and run it on the head with a 570.

[lcvette]

But the coolant system would make a mess..... Hahahaha

You can also fly from China to Alaska in a Cessna with enough extra fuel tanks, but why would you want to try?

[treyjugson]

With a 5 TPI ball screw the 570oz stepper will lift about 850 pounds.

The mill is less than 300 so you can turn it up side down and run it on the head with a 570.

how exactly did you come up with 850 pounds? at what rpm? microstepping? is this purely theoretical with no friction involved?

[photomankc]

Lead Screw Torque and Force Calculator

The calculator I have used in the past puts the maximum weight the 570 could lift with 0.25 Coeff of Friction at 268lbs. The head I weighed for shipping to the manufacturer is around 70lbs. Lets assume a 45% derate margin for torque fall-off at rapid speeds and some tight spots. That's 147lbs, leaving you with 77lbs of additional crap you can haul up the ways. Lets throw on a 40lb 6" rotary table at about 40lbs. That's still 37lbs of addons before you begin to violate the margin.

Now, certainly at that point the 906 begins to look better to add more margin for your possible need to use the head to help lift yourself into the attic. The 906 allows for lifting a 230lb load on the ways with the same margin. The 1200 will lift around 310lbs given the same margin. That's also 620lbs of force it can exert on parts at low speeds so, more than two times the weight of the whole machine.can be exerted on your bearing mounts, screw, and nut mount if you run into a hard stop.

Perhaps that helps put some real numbers into the choice.

[treyjugson]

i was asking arizonavideo how he came up with 850 pounds. i'm betting his calculations are as flawed as yours. holding torque moves nothing. i want to know at what speed his 570 oz/in stepper can lift 850 pounds.

[lcvette]

Lead Screw Torque and Force Calculator

The calculator I have used in the past puts the maximum weight the 570 could lift with 0.25 Coeff of Friction at 268lbs. The head I weighed for shipping to the manufacturer is around 70lbs. Lets assume a 45% derate margin for torque fall-off at rapid speeds and some tight spots. That's 147lbs, leaving you with 77lbs of additional crap you can haul up the ways. Lets throw on a 40lb 6" rotary table at about 40lbs. That's still 37lbs of addons before you begin to violate the margin.

Now, certainly at that point the 906 begins to look better to add more margin for your possible need to use the head to help lift yourself into the attic. The 906 allows for lifting a 230lb load on the ways with the same margin. The 1200 will lift around 310lbs given the same margin. That's also 620lbs of force it can exert on parts at low speeds so, more than two times the weight of the whole machine.can be exerted on your bearing mounts, screw, and nut mount if you run into a hard stop.

Perhaps that helps put some real numbers into the choice.

I really think you are missing several items in the equation used in that calculator. If you want to calculate it properly you need to use a formula that allows for the max uniform speed, Acceleration, Positioning time and takes into consideration all of the variables of the driven load. if you want to go through the motions, here is an actual correct formula used by ball screw manufacturers to help manufacturing companies size motors for torque requirements.

https://tech.thk.com/en/products/pdf/en_a15_053.pdf

I already know the answer for my requirements, and i think that is the difference is my requirements are more demanding where as you are comfortable with what your requirements and results are. But again i default to saying for a few bucks more, the ceiling is eliminated in my version of this story where as it is firmly in place in your version.

I am just trying to put my personal experiences out there and that has been accomplished, at this point if it helped i am glad and if not then it is what it is. I only have to live with my own decisions, as does each of you, so if you are happy with your decisions awesome, if not, you always get an opportunity to make another one. Only it sometimes comes with expenses..

Chris

[photomankc]

I am just trying to put my personal experiences out there and that has been accomplished, at this point if it helped i am glad and if not then it is what it is. I only have to live with my own decisions, as does each of you, so if you are happy with your decisions awesome, if not, you always get an opportunity to make another one. Only it sometimes comes with expenses..

Chris

Agreed. :cheers:

[CNCMachineplans]

I have had some people ask me how i measure up for my ballscrews so i thought i would do a video.on how i do it, it may not be the best way but it works for me

So Here are the measurements i came up with

Z Axis = 520mm + FK15 + 25mm For coupler & No float end
Y Axis = 300mm + FK12 + 25mm for coupler & No float end
X Axis = 25mm coupler + FK12 + 673mm + FK12 + 25mm Coupler

[CNCMachineplans]

So I have ordered all my ballscrews and stepper motors today so I will take pictures of those when they come in.

My questions is which breakout board to get. On my previous builds of CNC routers I have used a pmdx126 with a Ethernet smooth stepper but I don't want to spend that much again.

So I am after a cheapish breakout board and something perhaps with USB on it? On mynethernet smooth stepper I am getting some timeout issues every now and then so if anyone could make some suggestions as to what they use.

Thanks
Chris

[SCzEngrgGroup]

Homann Designs in Australia sells very nice breakout boards. Even with shipping, they're no more expensive than most "cheap" breakout boards.

Regards,
Ray L.

[CNCMachineplans]

Hi Ray.
I have been looking at those from homanndesigns as my first option and using a UC100 controller as well, that to me seems like my cheapest option. I just didn't feel it was critical to go all out this time on BOB's etc. Just was kinda seeing if anything new was out there that I hadn't coke across.

Chris

[CNCMachineplans]

Hi guys
Got my closed loop stepper motors today. I got one 1200oz nema 34 and 2 570oz nema 23 stepper motors. They look really nice and it came with all the wiring so it is very much plug and play so I am looking forward to setting this up. I will do the a YouTube video just showing a bit more about them.
Cheers
Chris

[CNCMachineplans]

Hi Guys
Well I got some milling done today on the CNC Router, Its all going really well but i sure am looking forward to flycutter capabilities, So I have me endplates done, My Mount for me Nema 23 and 34 done, and the top plate for the coloumn done, I just have to back the ballnut holder and the stand offs for the stepper motors and then i can start reassembly

Chris

[bladehunter]

Nice work

[pippin88]

Nice work. Looks like your TM25LV has nicer finish / construction than my TM20LV. For example the holes on the top of your Z look evenly spaced - mine seem to have been placed at random, which makes making plates difficult.

[CNCMachineplans]

@pippin88 the construction is OK to average, like I have mentioned before there's tight spots thru the dove tails the paint is flaking and chipping all over the place, the top of my dovetails has a big chip out of it and this is a machine thats suppose to be outta the same factory as tormach, to be honest if this is the same factory it kinda puts me of importing a tormach machine, but I am just looking forward to getting it back together and making it pay for itself and then hopefully upgrade. The bolt pattern in the top plate of the z axis is probably no better than the TM20LV by the sounds of it, it is all over the place but not by much, I was out by half a MM on 2 of the bolts so I will be redoing the plate. I got my ballscrews today so I will put up a video soon going over those
Cheers
Chris

[CNCMachineplans]

Hi Guys
I recieved my ballscrews and motors so heres a little video about where i am upto



Cheers