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View Full Version : 5-Axis machine - Opinions please!



Joshi
21-09-2015, 04:01 PM
Hi all,

New to this forum and happy to answer any questions about myself or why I want a cnc machine!

But the big question from me is:

What do people think of this???

http://www.ebay.co.uk/itm/5-Axis-CNC-3040-Table-Column-Type-Engraving-Machine-High-pricision-Ball-Screw/251354779186?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%2 6asc%3D32694%26meid%3D6031b646d70e478a8123f9c626a4 486e%26pid%3D100005%26rk%3D1%26rkt%3D6%26mehot%3Dp p%26sd%3D360545592989

Looking for anything you think about it - and mainly what you think of its capabilities for Aluminium and harder ferrous metals.

Ill include a sample image of the sort of thing Id like to produce with it - mainly looking at prototyping things with small, quite complex cuts that I believe a 5-axis machine will enable me to do (like phillips screwdrivers and 0.5mm slots.)

Thanks in advance!

Josh.

http://www.mycncuk.com/attachment.php?attachmentid=16131&stc=1&thumb=1

Blackrat
21-09-2015, 09:18 PM
the electronics on that machine is 100% junk ... sorry thats just my feeling :S ive had the same controller and it simply didn't work

i cant figure out what that part is you making ?

fidia
21-09-2015, 09:25 PM
Agreed. Would not waste 1p on it.

Joshi
21-09-2015, 09:26 PM
the electronics on that machine is 100% junk ... sorry thats just my feeling :S ive had the same controller and it simply didn't work

i cant figure out what that part is you making ?


Hmm, that was my concern. But hardware wise - would it be ok? Could I put a different control unit in there? (how? haha)

That particular thing isn't a part at all. It was a concept for a cycling multi-tool - spanners and a single screwdriver. Having not made it I would imagine it was flawed due to the thin walls on the spanners, but thats beside the point. Its pleasing to the eye and a good test for the mill because of the angles and the intricacy of the screwdriver tip. Im sure it would be do-able on a 3-axis. I just think i need a 4-axis at least for my actual products.

If you like it ill send you one once I have the damn mill :P

Joshi
21-09-2015, 09:26 PM
Sorry, double post. Cant figure out how to delete it.

Joshi
21-09-2015, 09:27 PM
Agreed. Would not waste 1p on it.

What would you recommend instead?

And do you have a reason - other than the obvious (surprising lack of detail, blurry photos and its chinese passport)

Christian Knuell
22-09-2015, 12:34 AM
Hi,


what you think of its capabilities for Aluminium and harder ferrous metals.

This machine is absolutely unsuitable for any metal (unsupported rails on XYZ and most likely timing belts for AB -> by far not enough stiffness).
For aluminum you may be able to build a small 5 axis machine from $10000 upwards - for steel at least double that number.

But mechanics are only one issue - software is another:

"Cheap" 5 axis software starts at about $5000 (I'm not joking).
Even if you manage to get a copy of such software it will be useless because you need someone to program a post processor for your machines kinematics.
Don't expect this kind of software to be easy to use - even CNC programmers with years of experience usually need to visit expensive training courses to use those programs.


5 Axis machining is absolutely out of reach for any hobbyist and even most businesses.

By the way: the part you've shown is possible with 3 axis as far as I can see - you just need to flip it once.
But even for just 3 axis you won't be able to find a machine with the ability to machine steel for just 1000.

Christian

Joshi
22-09-2015, 01:30 AM
Hi,



This machine is absolutely unsuitable for any metal (unsupported rails on XYZ and most likely timing belts for AB -> by far not enough stiffness).
For aluminum you may be able to build a small 5 axis machine from $10000 upwards - for steel at least double that number.

But mechanics are only one issue - software is another:

"Cheap" 5 axis software starts at about $5000 (I'm not joking).
Even if you manage to get a copy of such software it will be useless because you need someone to program a post processor for your machines kinematics.
Don't expect this kind of software to be easy to use - even CNC programmers with years of experience usually need to visit expensive training courses to use those programs.


5 Axis machining is absolutely out of reach for any hobbyist and even most businesses.

By the way: the part you've shown is possible with 3 axis as far as I can see - you just need to flip it once.
But even for just 3 axis you won't be able to find a machine with the ability to machine steel for just 1000.

Christian


An extensive and compelling reply. Thank you very much Christian, I really appreciate that.

I thought from the beginning of my research that a 3 axis machine would be enough for my needs - but as it often goes with research one thing leads to another and you somehow convince yourself you always need the next machine 'up' as it where.

What about the Boxford machines converted with Mach3? They're able to do mild steel from what their website and staff would have you believe. At my current stage taking something out and physically flipping it would be fine - how hard is this to do and align properly?

My budget is probably around 2500 but id obviously like to spend less than that if I can. And im happy to wait a bit to do so.

As another opinion, what do you reckon to this? (for Alu, not Mild)...

https://www.gumtree.com/p/other-miscellaneous-goods/desktop-cnc-icp-2015-milling-machine/1133751010

J

JAZZCNC
22-09-2015, 01:45 AM
What you actually want is 3+2 which Like Christian points out is way different to true 5 axis machining.

But anything done with 3+2 setup can be done with just 3 axis and fixtures/vises. 3+2 is just easier.

Forget those Ebay offerings for anything but learning because they just are not strong enough for cutting anything harder than frozen Mars Bar's.
The Linear components match the electronics on quality or lack of.! Structeral Design is very poor which would result in more chatter more than naked Ozzy in Artic snow storm.!!

In all honesty you'll need minimum of 3K to even build any half decent machine with 3+2 capabilty's able to cut steel's. You'll need at least double this to buy any pre built machine worth having, if you can even find one.!!

JAZZCNC
22-09-2015, 02:17 AM
As another opinion, what do you reckon to this? (for Alu, not Mild)...

https://www.gumtree.com/p/other-miscellaneous-goods/desktop-cnc-icp-2015-milling-machine/1133751010

J

This is quite similair design to Denford router and I can tell you now they are no suitable for aluminium despite what the blurb may say.
There's a big difference between scratching and cutting and the simple truth is that cutting harder materials requires a ridged machine with the correct spindle.
These Boxford/Denford type machines are light weight machines designed for teaching students in range of materials so while the Blurb says they cut aluminium what they actually should say is they scratch Aluminium away. If you want resonable feed rates and decent finish quality then these light weight machines are not strong enough for cutting Aluminium correctly and Just plan unsuitable for steels.

The machine you require for cutting steels and aluminium correctly when buying off the shelf is a Milling machine, which is actually hard to find and quite expensive when you do because of the spindle required.?
Aluminium requires spindle speeds in the 8-14000rpm range and higher if smaller tooling. Steel requires anywhere between 100-3000rpm and lots of torque.
Spindles with low to high rpm with torque are very expensive and quite hard to find Off the shelf Milling machine with one. When you do you'll need to sell the family to afford one.!

If you build a machine then it's possible to get machine that will do both but again the spindle plays a huge part and cost's lots. The design needs to be strong and components used of resonably quality and matched to the application. All this cost's far more than 1K and like I say 3k will be a more realistic figure for a good machine worth the effort.

Sorry if this isn't what you want to hear but it is realistic reply.!!

Joshi
22-09-2015, 02:30 AM
All this cost's far more than 1K and like I say 3k will be a more realistic figure for a good machine worth the effort.

Sorry if this isn't what you want to hear but it is realistic reply.!!

No no, on the contrary, this is EXACTLY what I need to hear. Actual solid advice! Thank you all so much. My budget, if I'm honest, is complete guesswork as Im in talks with lovely people about something of a cash injection to get me off the ground.

If you guys honestly believe it possible and 'better' to build my own truly Aluminium (and possibly harder material) capable machine then I am totally all-ears.

But for the sake of argument, what sort of machines would I be looking at - if you could provide names or links to pages that would be chuffing excellent. Im all about the research and the more data I have to go on, the more I can get stuck into it :D

Christian Knuell
22-09-2015, 10:10 AM
Hi,



As another opinion, what do you reckon to this? (for Alu, not Mild)...

https://www.gumtree.com/p/other-miscellaneous-goods/desktop-cnc-icp-2015-milling-machine/1133751010
(https://www.gumtree.com/p/other-miscellaneous-goods/desktop-cnc-icp-2015-milling-machine/1133751010)

honestly very hard to tell because you can't see the guides. Considering the price I doubt it to be suitable for aluminum - I wouldn't risk it.

If you really want to machine steel for as little money as possible maybe an "BF20" clone (something like this http://www.ebay.de/bhp/optimum-bf20 but there are many more companies with very similar machines) converted to CNC ist the best choice.
Those machines are small, cost quite some money until they are converted to CNC and are still far from a "serious" machine for steel machining - but at least they get the job done.


Christian

JAZZCNC
22-09-2015, 03:25 PM
If you guys honestly believe it possible and 'better' to build my own truly Aluminium (and possibly harder material) capable machine then I am totally all-ears.

But for the sake of argument, what sort of machines would I be looking at - if you could provide names or links to pages that would be chuffing excellent. Im all about the research and the more data I have to go on, the more I can get stuck into it :D

Yes it's more than possible to built your own machine capable of cutting aluminium and mild steel but it's not an easy or cheap task and something I wouldn't encourage a new person to under take.

The main issue is you really need another machine to build the next machine to achieve the accurecy and strength required. Then you have the Cost.!!
The cost of a spindle alone capable of cutting steels correctly and still be fast enough for aluminium will start around 2000 -2500 upto 4-5K. So hopefully you can see some of what your up against.

Now if you lower your sights and stick with Aluminium/brass being the upper limit then with the right design and choosing the correct components then it's possible to build a very nice machine with 3K. Cutting Steels really does take you into another zone.!!

Converting a Mill is an option but IME if mostly cutting aluminium then they are not always ideal. Again it's the spindle speeds.!! Upgrading the spindle isn't always possible and if it is then it won't be cheap upgrade to do correctly.

I have seen German made Wabeco Mills that have High speed spindles but they have all been very expensive.!

Joshi
22-09-2015, 09:30 PM
Ok - so this is the reply they sent me. Confirmation its to be avoided?

"Hi Josh
Thanks for your message .

This is a full set machine, with water cooling pump & hand controller, but if you need it to work perfect, you need to connect it with a PC.
It is controlled by Mach3 software(we have a software CD to go with the machine, on the CD, there is a demon version Mach3).
When you got the machine, you can install the software on your desktop PC(Window XP/2000) by LPT port.
There is a brief manual on the CD, you can set up the software following the manual guide, when you have this work done, the machine can run normally,
but if you need to make it work for your need, you need to do some CNC drawing & programming on other CNC software first,
then load the program on Mach3 so that you can make the machine to do your own work accordingly.

We have 1pcs 3mm bit & 1pcs 6mm bit included in the package for you, if you need some other machining bits, you got to prepare them by yourself.

This machine can work on metals like Aluminum, brass, stainless steel etc, here are some video for your reference:
http://i.youku.com/u/id_UMTM0MDQxOTc2OA==


The item will be shipped via DHL ,usually you will receive the item 12-15 business day
The business day is not include saturday and sunday .

We do appreciate your understanding and time.
If you have any questions,feel free to contact us,we are always here to serve you.
Looking forward to your reply
Best regards
Candy"

Video link - http://v.youku.com/v_show/id_XNzA0ODI0MzAw.html?from=y1.7-1.2

komatias
23-09-2015, 12:32 AM
Some of these videos are pretty persuasive:

https://www.youtube.com/results?search_query=chinese+3040+5+axis

JAZZCNC
23-09-2015, 12:41 AM
I'm sorry but this is not cutting.!! . . . . I see scratching, rubbing and hear plenty of resonance but not much cutting going off.!!


https://www.youtube.com/watch?v=hG5drLe5Jgw

komatias
23-09-2015, 07:59 AM
Agree, should have written "dissuasive "

Best get a converted machine or see if exonomical to farm bits out

DuffelBuffelWuffel
23-09-2015, 08:25 PM
Same as I posted in the thread of the other guy:
Buy FS4MG LANG and add one of those china 4th/ 5th axis.
http://cnc-technik-mueller.de/fs4mg-lang-mineralgussmaschine/

This + usbcnc (Eding) + leadshine closed loop stepper 2nm (ebay) + gdk80-12-24Z/1.2-2.2 spindle
But be prepared that the end price is around ~6.5K euro without tax
Fusion 360 as CAM software (3+2axis) "free"

Also buy a haimer 3d probe , a bunch of 1/2/3 flute VHM mills for alu and a decent toolsetter + add limit switches to the machine + a decent vice (the Vertex VA4 fits nice on the bed)

Now you home the machine -> inset the haimer probe -> it auto measures length and does compensation (G49) -> zero the stock
Now run your code -> insert endimill -> auto measure length and G49 it (saves you so much time and makes your tolerances much better).

Having a spindle that has ATC is even better ... but those are quite pricey.

I have not done any steel yet , but I can't see why it is an issue (forgetting the spindle speed).
They Also Have the FS3MG which is "made" for steel. The base price is quite a bit higher but still doable for a small business.

hanermo2
25-09-2015, 04:30 PM
Its perfectly possible to build, yourself, a machine for milling steel.
99.9% of people who start, fail.

I scratch-built a VMC.
It went like this.. (as my wife reminds me..)
A couple of weekends and some hundreds of €€...

((Router->Bridgeport M head-> ISO30 spindle)).

15.000 work hours later, I am finishing the V3 iteration of what is now a commercial quality VMC.

This is what it entails;
32 mm ballscrews, 1200 mm working length
Moving table, in steel, 1600x500 mm, 60 mm thick, 200 kg in mass (will double to 400 kg and 11 cm thick)
35 mm linear rails and trucks
ISO30 spindle (about 1300€, they are not that expensive)
Brushless AC servos, 400W, 1.3 Nm continuous, 3.9 Nm peak
125 kHz hardware controller for high pulse rates

Current step size is 0.2-0.3 microns on each axis.
Machine is 2.3 wide, 1.6 m tall, 2 m deep, approx 2000 kg in mass, all built in basic local tool steel "F1 calibrado".
Table size is 1600x500, with 1200 x 1200 work area.

Most people wont have the patience, time, space and ability to continue for so long, until you finish something like this.
I am now a professional machine builder, with factory training from a major manufacturer (2 years ago).
My own machine costs about 20k in components.

Retrofitting an old manual metalworking mill is much easier and cheaper.
A scratch built machine is much better (more work envelope for cost and volume, more rigid for the mass and size).

Current machine rigidity is 17N/um, which is acceptable industrially.
Goals are 10-70N/um rigidity according to industrial guides and textbooks on machine design.

A good set of retrofit gear costs about 2500€ and up.

JAZZCNC
26-09-2015, 01:16 PM
Its perfectly possible to build, yourself, a machine for milling steel.
99.9% of people who start, fail.

Ye and After spending trying.!!


ISO30 spindle (about 1300, they are not that expensive)

Hannu where are you buying Iso30 spindles from @1300euro.? Also what rpm bearings.? I presume your using a Servo to power it.? If so what size and RPM.

Hows the Lathe upgrade coming along.? I'd like to see this working when it's finished so please post a video. Also the mill. .:encouragement:

hanermo2
26-09-2015, 01:30 PM
The ISO30 ATC spindle has a cost of 1300 to me, with the sales tax paid, here in the EU.
I import my own stuff, and can include extras in each lof, if someone wants some.
These usually arrive about once per month.

The spindle has 7000 rpm bearings, theoretically.

Im not sure, actually, what I will use to power it.
I will probable get a servo, and I will probably need to order it with the next lot of stuff.

My bridgeport mill 3-phase motor works.
I have a spare 2.2 kW VFD.
A new motor (second hand) is very cheap.
So, for maybe 100-150 I can get a 2-3 kW motor, and I might do that to try.

I dont have spare, large, servos, only 750 and 400W ones, atm, but this changes.

I very much wish to do rigid tapping, and high-speed accelerations, ie servo.
Yet, a 2-3 kW servo is about 1600.

The spindle should handle 5-7 kW, theoretically.
My machine frame, hopefully, will do 3 kW.
If it does, I will be Very Happy.

Anything above 1 kW cutting power is fine, for me.
The machine is very large re_frame, but I dont expect to do major metal removal. If I do start doing so, then a big servo is the first thing.




Ye and After spending trying.!!


Hannu where are you buying Iso30 spindles from @1300euro.? Also what rpm bearings.? I presume your using a Servo to power it.? If so what size and RPM.

Hows the Lathe upgrade coming along.? I'd like to see this working when it's finished so please post a video. Also the mill. .:encouragement:

hanermo2
26-09-2015, 01:38 PM
The lathe upgrade is progressing !!
Wenesday, first side plates, friday, last side plates, friday, the lockbar tap broke inside the spindle motor lockbar piece !

Today, after getting new M8 tap, main drive lockbar is in place !
This locks the spindle mount solidly in pace.
Material is 20 mm thick tool steel plate, and 30x50x350 mm bars, 3 of.
All on top of the lathe, where they belong.

I learned this trick from Haas.
When the motor is above the spindle, the heat does not go into the spindle and headstock.

1.
Now, to disassemble all the main spindle, new saddle, mounts and sideplates.
Sand everything (dirty, noisy, heavy work. Yum. But goes fast, with a festool 1400W industrial hand sander).
Primer.
Leave to dry till monday ..

2. or keep going, until x axis servo is in place.
Maybe option (2)..

DuffelBuffelWuffel
26-09-2015, 02:27 PM
Especially the ATC is handy , but the ridget tapping is not needed.
I use this:
http://www.sorotec.de/shop/Zerspanungswerkzeuge/Gewindefraeser/VHM-Gewindefr-ser--4-0mm-f-r-M5---M10.html

For M5-M10 thread with my HF spindle 2.2kw , they also have it for other sizes and other kinds of thread mill.
It is really easy to set up using HSMWORKS or HSMEXPRESS, doing it with fusion 360 is not hard either.

In that case you would not need a servo but just a simple 3 phase motor.

NYCCNC guy has a video about thread milling, he also explains the downsides of ridged tapping etc...

hanermo2
26-09-2015, 03:18 PM
Your completely right about thread milling.
But..
My customer base thinks rigid tapping is a basic, needed, feature.
Thus, I have a commercial incentive to demonstrate it.

So that the stuff can be taken seriously.

DuffelBuffelWuffel
27-09-2015, 03:07 PM
In that case... as long as they are willing to pay extra for that functionality than you can go for that feature without making costly compromises.

Chaz
18-12-2015, 10:56 PM
Some pics or vids of this beast please?

Chaz
18-12-2015, 11:01 PM
Its perfectly possible to build, yourself, a machine for milling steel.
99.9% of people who start, fail.

I scratch-built a VMC.
It went like this.. (as my wife reminds me..)
A couple of weekends and some hundreds of ...

((Router->Bridgeport M head-> ISO30 spindle)).

15.000 work hours later, I am finishing the V3 iteration of what is now a commercial quality VMC.

This is what it entails;
32 mm ballscrews, 1200 mm working length
Moving table, in steel, 1600x500 mm, 60 mm thick, 200 kg in mass (will double to 400 kg and 11 cm thick)
35 mm linear rails and trucks
ISO30 spindle (about 1300, they are not that expensive)
Brushless AC servos, 400W, 1.3 Nm continuous, 3.9 Nm peak
125 kHz hardware controller for high pulse rates

Current step size is 0.2-0.3 microns on each axis.
Machine is 2.3 wide, 1.6 m tall, 2 m deep, approx 2000 kg in mass, all built in basic local tool steel "F1 calibrado".
Table size is 1600x500, with 1200 x 1200 work area.

Most people wont have the patience, time, space and ability to continue for so long, until you finish something like this.
I am now a professional machine builder, with factory training from a major manufacturer (2 years ago).
My own machine costs about 20k in components.

Retrofitting an old manual metalworking mill is much easier and cheaper.
A scratch built machine is much better (more work envelope for cost and volume, more rigid for the mass and size).

Current machine rigidity is 17N/um, which is acceptable industrially.
Goals are 10-70N/um rigidity according to industrial guides and textbooks on machine design.

A good set of retrofit gear costs about 2500 and up.

Some pics / vids of this machine?