I have been reading the forum for a while now, I finished my studies as CNC programmer and operator and even If I have a good understanding of cnc machining I still have a lot to learn and that's the reason I create this topic.
I'm negotiating the price and caracteristics of a cnc router from the company Philicam, I will list all the details of the machine here, but I have the feeling that my questions about technical details of the machine (as power diagram of the spindle, torque of the servos, precision of the table etc) are bothering the manufacturer.
First of all I will resume what will be my milling requirements, I am planning on making signs (pvc, abs, plexiglass,wood) but also stone and aluminum engraving.
I will surely have some rare aluminum or steel milling work to do and of course a gantry (especially of this size) is not the right tool for such jobs, the seller told me it would mill steel and aluminum with no troubles but I'm really guessing it will be the opposite. My idea was to mill aluminum and steel only using high speed/small cut milling strategy but I have no idea of how the machine will react.
To make it simple I am looking for a machine able to process most of the common materials with a size that permits to mill large boards and with the maximal rigidity possible.
Now for the machine specs:
1. Working area: 1500*3000*200mm
2. Price: 16500$
3. 7.5 KW water cooling spindle with 8 auto tool changer (BT30) max 15000rpm.
4. Delta servo motors and drivers (working speed 20-30m/min rapid speed 60m/min)
5. 7.5 KW Fuling inverter
6. NK300 control system
7. T-slot or Vacuum table (still have to decide because I would have liked a steel table and they use aluminum frame table)
8. X,Y axis gear transmission, Z-axis Taiwan TBI ball screw transmission.
9. Dust collect system
10. Z tool lenght sensor
For the coolant they want me to take the Spray Cooling System, I already worked with this type of lubrification, it is fine even if water based coolants are more effective, but my problem is that there is no extractor for the oil mist and I don't want to cover the room in oil or breathe that each time I have to machine a part requiring lubrification.
I would like to use a water based coolant (especially for stone carving and slotting as I am planning on producing tombstones and stone signs) but I'm not sure they will be able to make a machine table with coolant drains, water tank, filter and pump.
Now that I have told you all that, what are your advices?
Is this machine the correct choice if I'm looking for a polyvalent machine able to process many materials and having a large working zone?
knowing that the price I mentioned is already the limit I can invest for my first machine can I hope milling aluminum and steel parts?
I would be very doubtful if that machine will mill steel at all to be honest, never mind stone. Ask them to show you a video demonstration of milling both from a tool path you created, I bet they run for cover
To begin with, if the machine has anything other than a strong, well supported torsion box made of welded and stress relieved steel it won't hold anything that is heavy particularly flat, irrespective of the type of table it has. The Gantry should ideally be one piece welded steel for any heavy milling operation with as large a linear rail as possible, 20-30mm at least. Plastics, composites and wood etc should be no problem on a lighter duty frame. Aluminum might also be possible if you take it easy, use the correct mill and have good compressed air flow to remove chips. Stone cutting would really require a machine designed for the purpose to do it any justice and this machine just doesn't look up to that task. The drives etc are really a matter of choice, I like Yasakawa and Panasonic AC drives, but the VFD should really have a much larger capacity than the spindle it is driving. Again, the controller would be a matter of choice, but choose something straightforward to use that has good manufacturer support.
I have no idea if you will achieve that in your budget, but you don't seem to have factored in the shipping costs
Thank you very much for you helpful answer,
For the frame of the machine they told me it was the heavy duty version made from 8mm thick steel that will be stress relieved, when I asked what was the maximal table load they told me 1 Ton...
For the servo motors the price is what made me choose the Delta servos but now I'm really asking myself if they will create any problems and if I should go with Yasakawa servos.
Thank you for the linear rail size and vfd power advices I will ask for this options.
About the controller I really have little knowledge of what is made in China, the only ones I used is a 200khz usb Mach3 board but it have nothing to do with the NK300 controller. If there are any suggestions for the controller feel free to tell me, I already worked with Mazatrol, Shopmill, Heidenhain, Haas but I really don't know what is made in China. If it will take standard Iso gcode that I can postprocess from most programs it will be fine for me and of course is able to read a large file from an usb up to 1go is fine.
For the transport I work with a company in Guangzhou that will take care of the shipping, this is why I haven't counted it here, my budget for the machine was around 16500$.
Most of the work will be cabinet manufacturing but it would have been great to be able to process stronger materials. As it is my first machine and that I'm starting my company I have limited funds and am just trying to get the best I can for this amount.
Thank you again for you help, it really is useful.
Hey, I didn't mean to scare you off the Delta servos, I just mentioned my own preferences. The Delta stuff is probably fine, but I don't use it. I only spec Yasakawa or Panasonic motors and drives for my clients because the build quality is known to me and spares are readily available in those rare, unfortunate circumstances where they are required.
Now that I have a little more information from you to go on, I can make a few more comments/ recommendations.
The common standalone CNC controller manufacturers on the Chinese machines would be Syntec, Adtech and Weihong (NK300). There are others obviously, but less well known. Of these, the Syntec has a bit of a following here at CNCZone, so some help may be available from some of the other members here if you get stuck. As controllers go, these are all either based on WinCE or a stripped down version of WinXP, but like all things CNC, there will be a learning curve no matter what controller you go with. I see no real reason though why any of them would be an obstacle to you running cabinet parts. I would mention that you need to make sure that a good post-processor is available from the manufacturer of the controller for whatever CAM software you plan on using, this is vital to avoid jumping through unnecessary hoops with bad code.
The machine and spec that you have shown makes no mention of rail lubrication, an oiler is a very handy thing to have for the rail system, an auto oiler even better. It will save you a lot of hassle and elongate your maintenance cycle. Also, you have chosen a machine with a linear ATC, from the photo shown, if speed is critical to you, you may want to consider a carousel type on the gantry. The Taiwan ball screw on the Z axis may be fine, but I would be wanting something better given the money invested in the rest of the machine. I'm always a fan of German engineering, maybe Raco or something. You also mentioned that you are undecided on a vacuum table. If you do opt for one, make sure you factor in the cost of a decent pump. Steer well clear of Vane type blowers and Water cooled pumps. they are all heartbreakers and only cause more problems than they solve. The only two pumps worthy of my money is the German Becker or the Chinese Tongyou, which is a Becker copy. The Becker is obviously the better pump by a mile, but it comes at a cost. I know that you mentioned that the shipping is taken care of, but there will likely be customs fees etc at your end to be aware of. I probably don't need to mention it, but given the spec, make sure that you have 3 phase power available wherever you plan on installing it. I haven't really mentioned anything that you couldn't retro-fit at a later stage, albeit a hassle, if money is a real concern, but this would obviously require down time and engineering which depending on how busy the machine is, may outweigh spending the money upfront to begin with. I hope some of this helps you avoid a pitfall or two
In the interests of full disclosure, I am a UK based agent for Quick CNC. I am in no way attempting to sell you on any particular manufacturer here, just giving out some friendly advice as a member. If you would like me to quote for a machine, I would obviously be only too happy to do so as soon as the factory opens again after the holiday