C Axis opinions and help please

Hi All

I run a small workshop and its a one man show. I machine plastics and small odd jobs bigger companies generally don't want to do.
I have a Vision Widetech VMC with fanuc 18i-mb controller that is 4th axis ready.
Its been great for the past couple years but now I need a C axis.

I had a quote from the company that sold me the machine and its quite pricey.
The unit they were selling is made in Taiwan.
So I was thinking if it would be possible to buy a cheap Chinese unit and have a technician just come in a wire things up.

If this is possible can anyone suggest to me what I'll need to purchase for this to be possible. I know I'll also need to purchase a servo amplifier and that's all I know. Is there anything else needed?

I was told that everything needs to match up, does this mean the amplifier needs to match up with the other 3 amplifiers as well?

Does the brand of the rotary matter for a Fanuc controller, is there anything i need to look for in the unit?

Should I buy a secondhand branded unit, tho I think this is still expensive.

I would like the rotary to have full contouring capabilities too.

Any help and suggestions hugely appreciated.

Thank-you in advance

Quote:

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I would like the rotary to have full contouring capabilities too

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hy qwerty :) in this case, considering that your machine is allready "4th axis ready", you should go along with your initial vendor, or, pehaps, a different vendor of the same brand.

however, if machine is still under warranty, then you may lose the warranty if another fanuc vendor is messing with it

even if initial price is high, at least it is a guarantee that it will work, but, even if you have the money 2 go with your initial vendor, be sure that your controller + 4th axis will deliver real 4th axis motion, and not only positioning : not all controllers are capable of delivering 4th axis interpolation :)

other options :
... there is a kitagawa stand-aloner, thus a 4th axis with integrated nc ( Quinte ), that requires minimal stuff to be conected to a cnc, and had been desgined as portable, like to move it between different cnc brands; contact kitagawa, but considering the versatility of this products, it may be more expensive :)
... try to buy not a new one from your initial machine vendor, but an original refreshed one, if available; some rotary axis producers also bring to back to life some of their used products
... if you are lucky :
...... maybe there is someone that has a 4th axis on the shelf, and wished to get rid of it
...... get a random 4th axis from somewhere, and find someone that can conect it with your machine

kindly :)

What deadlykitten said ^^^^^

Deadlykitten thank-you for replying, I think I'll go with the original vendor to be safe. I just wanted to get some opinions as this is a big investment for myself and considering the current state we are all in, with lockdowns and such.

hello again and welcome to the market of cnc spares and accesories :)

i was thinking about your post ... you should now something : going for accesories, etc, requires every piece of the puzzle to fall corect into it's place, otherwise it won't work, and the best fit is the one from your cnc official brand vendor; but be careful, because bestfit doesn't always mean that it works : it may work like a charm, or experience whatever issues from day 1 until forever, even if parts are original and installed properly

check if your vendor allready installed a similar product, and that it is working and it is delivering what you wish to achieve : seeing it in action, interpolating on all 4 axis, before deciding to buy it, should feel better :) there are clients that received an upgrade that was delivered for the 1st time in a specific area, and it did not function properly after installation, but after a while, like months ... such chances exist, but they are lower with common upgrades, like a 4th axis :)

if you wish to save your money for a while, try to find a shop with an y lathe or vmc+4th axis and colaborate with it : you may get feedback ( technical and costs ) from 4th axis work without having yet the 4th axis yourself, so, it may be one way to know what to expect .... meanwhile, if you wish, try to craft (or at least design) accesories for your future 4th axis : a mini-tombstone and/or a livecenter and/or a steady rest, so to extend the L/D ratio that can be clamped inside the 4th axis ... then buy it :)

one last trick : on a cnc machine, is no need to always align the 4th axis table : just clamp it, probe it, and rotate your program, and, before machining, check if rotation is correct; not everybody knows this, so some leave the 4th axis on the table, trying to avoid all the setup time

that's all :)

ps : hy jim :)

I may be missing something here (my experience is with wood routers), but doesn't a C axis rotate around the Z axis? On an earlier machine I had, my C axis rotated concentric to the spindle axis. Used it with manually adjusted angle tooling.

I'm looking to do 4th axis work now on my machine and that will happen in a Y or X configuration (B or A alignment) between centers.

Also, I presume you've determined that your future work is well suited to a C axis? Make sure your vendor knows how you intend to use the device. He may have some alternatives to offer.