Newbie on a budget wants to get a small CNC lathe

Hi guys,

I'm new on cnczone, looks like there is a ton of information and knowledge I can learn from here :)

I'm interested in getting a small budget cnc router to cut small (20-50mm wide and across) parts I stainless steel.

I was looking At some Chinese made compact cnc routers (4-5 axis) selling for around $2000 with water cooled screw ball head and pretty stiff looking chassis,

What the seller could not answer me, is if i could use one of these to machine small parts from stainless steel blocks,

One model was the "3040".

Does anyone knows this type of machines ? Could they be ok to start with?

Any help will be so much appreciated :)

Thanks!

No not for stainless.

Not even for mild steel. Probably not aluminum very well.
For aluminum and maybe mild steel, some of the small cnc mills might do the job, if it is a small one. The bigger the mill, the better your chances that you can machine SS.
A router format just will not have the necessary stiffness.

Thank you all for the tips, if so - is there any budget machine that I could machine small stainless parts with ?

I'm not looking for a machine that capable of dozens of parts per day, more likely to produce small quantity parts, e.g a pocket watch case?

I could attach a cooling system (nozzle + pump) to most machines as much as aware (correct mend I'm wrong)

Thanks!

This is the Chinese machine I was taking about Attachment 253046

That may stand a chance of working for you. It all depends on the stiffness. At $2000, I can tell you that it is lacking in that.
I designed and built my own small mill using 80/20 as a skeleton to attach high quality some over sized parts to using steel and cast iron as mounting surfaces. It uses a little better spindle head I think and a lot more powerful motor.
It is just barely stiff enough to machine SS. I would not want to do much of it on there. I have over $6000 in that one. It has been upgraded a few times though. That added to the investment.
That machine looks more designed to machine wood, plastics, etc.

What type linear ways does it have?
What type power transmission?

I see, thanks for the information!
Is there anyway to upgrade the machine ? (e.g. replace the spindle with a higher-torque drive, reinforce the machine body to make it more rigit, etc..)

Here are the specs of the machine i've mentioned and have shown in the photo:


1. Product Dimensions: (H)520 * (L)660 * (W)580 (mm)
2. Effective stroke 300*400*150 (mm)
3. 1605 precision ball screw slide rails
4. X & Y Axis are with hardened chroming rails, diameter 20mm; Z axis is hardened chroming rail, diameter 16mm
5. XYZ Axis Stepper motor: 57 * 78 Stepper motor 250 OZ/IN （2.2N/CM）
6. Re-orientation accuracy: 0.01mm;Machining accuracy: 0.02mm
7. Machining speed: ​​0-4000mm / min
8. CNC table Maximum Loading: 50kg
9. Stainless steel backsplash
10. Integrated switching power supply: 24VDC 350W.
11. Main Axis: 800W industrial water-cool frequency spindle.
12. 1500W industrial spindle inverter.
13.5-axis professional driver board with LCD display & controller,
supports off-line programming, routing memorized function and machining repeatability
14. The 5 axis used 175 OZ/IN (1.26 N.M) stepper motors, ratio: 1:6
15:Main Material: Aluminum Alloy
Electrical properties ( ambient temperature Tj = 25 ℃ ) :

1: Integrated high-speed microcomputer intelligent control chip, can be equipped with external LCD monitor with hands, automatic detection of computer controlled automatic shield handle motion control functions, can simultaneously track digital recording of computer data and handle mobile data control
2: The computer keeps track of the path, you can run once the computer processing of the data record-keeping process automatically repeats offline processing operation.
3: Manually move the processing to save recorded track record manually move the machine data and automatically reprocessed run manually move the path.
4: Manual data input processing path and enter the path to run automatically
5: You can automatically complete the XYZ axis or Z axis of the knife, without complicated computer software operation control
6: Max 5A stepper motor drive current, eight-speed adjustable.
7: Up to 16 segments, higher accuracy, run more smoothly.
8: Overload over-current over-temperature protection function, automatic semi-flow control, fully protect your computer and peripherals
9: Bipolar constant current chopper drive motor low-speed non-creeping phenomenon, noise, non-resonant region.
10: closed optical isolation, dual-stage signal processing, and fully protect your computers and devices.
　

Input Power
220AC power supply ,If you need 110V ,Pls let us know

Output Current
Drive 4.5A (peak 5A)

Driven approach
Bipolar constant current PWM drive output.

Drive motor
57 * 78 stepper motors, two-phase 4 wire stepper motor)

Weight About 45KG

Quote:

---

Originally Posted by LeeWay

That may stand a chance of working for you. It all depends on the stiffness. At $2000, I can tell you that it is lacking in that.
I designed and built my own small mill using 80/20 as a skeleton to attach high quality some over sized parts to using steel and cast iron as mounting surfaces. It uses a little better spindle head I think and a lot more powerful motor.
It is just barely stiff enough to machine SS. I would not want to do much of it on there. I have over $6000 in that one. It has been upgraded a few times though. That added to the investment.
That machine looks more designed to machine wood, plastics, etc.

What type linear ways does it have?
What type power transmission?

---

Personally, I think you would be wasting your money. It might work okay machining wax and milder plastics. Maybe PCB's. It sounds like it has unsupported rod as the ways. They are short because the machine is small, however they still flex too much to machine even aluminum very well. As for stiffness, I would say it doesn't have any. That price range for a new machine cannot hope to machine metals of any kind. You would be far better off converting a small mill to cnc yourself.

thanks for the tips !

and what if I will reinforce the aluminium body with extra thick reinforcement plates ? whould that add to the machine's rigidity ?
like on the attached photo:
Attachment 253472

note the red triangles.

Gussets will certainly not hurt anything, but the non rigid part to be concerned with first is the ways or bearings and rails that the axes ride on. They are not stiff and will flex.

Thanks for the feedback LeeWay :)

If I'm thinking about it - How do I go about stiffing the rails and bearing of the axis ?

Should it be done by replacing the stock parts (that came with the machine) with higher-end parts (sold on the bay?) ?

Or should I add an additional ballscrew and rail for each ax (double will flex less than single ?) ?

Many thanks!

P.S: off topic - about a spindle, I've seen direct-driven spindles and belt-driven, I've been told belt-driven gives much more torque since they give the open to install an oversized spindle motor, whats about it ? and if i'm replacing the step motors from nema23 to nema34 should it give the machine more "grip power" ?

Quote:

---

Originally Posted by LeeWay

Gussets will certainly not hurt anything, but the non rigid part to be concerned with first is the ways or bearings and rails that the axes ride on. They are not stiff and will flex.

---

Look into a used knee mill thats been fitted with an eztrak type system

That machine uses thin unsupported rods for the rails on all three axis. It is not suitable for machining metals. It might make a good 3D printer though. The vendor also sells each single axis actuator separately and also provides a look into the actuator box. Take a look and judge for yourself.

John C

Thanks for the replies guys! It gives me a lot of info on what to look for!

A Taig mill is a budget friendly option. It can cut steel albeit slowly and Taig claims it can do stainless. It is a great machine to learn on and holds its value fairly well so you won't be out of pocket too much when you upgrade to something bigger. You can get a control box from several sources (Soigneris and deepgroove1 are reasonably priced). Or you can build your own control box. I would recommend a Gecko G540 with suitable motors and power supply. Avoid most of the cheap TBxxxx packages on eBay.

bob