When it comes to better routing quality do you think stronger axis assemblies are more beneficial than linear rails and closed loop stepper ?
Hey Arthur,
I think you can’t tell this in general. All factors have an impact on the stiffness of the machine.
Also there are much more factors. If your bit is dull or you choose a too long bit which will bend, the best machine cannot compensate this. There is good knowledge and much experience required to make the best out of a machine.
If you ask regarding the Onefinity machines, the first thing I would recommend is not to use a hand trim router as milling motor. A strong induction motor as milling motor allows what a hand trim router would not allow: High speed at high torque, and a wide speed range with high torque to choose from. Machining wood requires both, high torque and high rotational speed. A hand trim router provides its nominal torque only at a specific speed, not over a speed range.
The Onefinity machines are extremely sturdy. They are monsters regarding weight. Their rails are made of 5–6 mm thick chrome-plated, hardened steel hollow shafts. Using a hand trim router on them is a like a bad joke.
Closed-loop steppers are often overestimated. In most cases, they don’t prevent a bit break and a blank damaged, even if the machine stops at a certain moment. Open-loop steppers are by far the most-used stepper motors for CNC machines. If they are correctly sized, they will perform as well as closed-loop steppers.
The drawback of stepper motors, both open and closed-loop, is their limited speed. Servo motors can be ten times faster, but their control electronics is more complicated. That is why they are usually much more expensive than stepper motors. Stepper motors have the steps implemented in hardware, servos only rely on the position sensing and controlling position by a lot of computation.
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Thank for the informative and interesting reply. Asking questions of people rather than bots is a much better way to go.
I am still shopping and learning. My background in ceramics seems to be directing me towards smaller table-sized CNCs and I am inclined to think even the OneFinity Woodworker is over-sized for me.
Based on what I have learned about CNC technology has also made me hesitate getting a OneFinity because of their relatively low torque stepper motors. Your comment seems to validate that concern.
Regarding frame/axis robustness, the size expandability of CNC beds (below 32 x 32 inches) appear only available in the less robust models.
On the other hand linear rails and/or closed and open loop steppers are readily available in pre-assembled models.
I suspect I need to expand my search to include more CNC manufacturers.
Maybe the Onefinity Machinist is more your fit (16x16)?
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Yes, good point, but the Elite series, with its heavier materials, closed loop motors and Masso controller are distractingly attractive. I’ll take another look at it.
Hey Arthur,
The hardware of PRO and Elite Series is identical. The PRO now have the 30 mm drag chains of the Elite Series and are also delivered with the Z-20 “heavy” Z assembly. So they differ only from the CNC controller and its power supply, and the stepper motors. The Elite has photoelectric limit sensors while the stock PRO and Original Series rely on stall homing (but you can retrofit limit sensors on the PRO and Original Series too). Both PRO and Elite Series have 50 mm rails on X axis.
There is however no machinist (16" Ă— 16") model on the PRO and Elite Series. The Original Series differ in that they have only 35 mm thick rails on X axis.
The torque required also directly depends on the ball screw pitch. With a flatter pitch your motors don’t need to have as much torque as with a steep pitch.
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It is great to know that I could retrofit the sensors to match the Elite, do you think I could also buy and use a Masso controller?
With the Machinist, you get an incredibly stout machine for the $$. It uses the original 35mm dia. rails, so the size of the machine does not really merit an upsize to 50mm. Heck, 35mm is almost overkill on this machine, which is one of the reasons it’s so stable & repeatable.
If you do like to tinker and don’t mind throwing some more $$ at it, there is nothing stopping you from sourcing your own Masso (or other) controller & closed-loop steppers, if you’re so inclined. Plus, you can make a decent aluminum frame base for the machine without breaking the bank. All depends on your project size. I just got done making a 12" x 24" sign that I had to tile. With any of the other machines, that would not have been necessary. Having a very small work area, I like my Machinist and will work around the occasional and rare times I need to tile a job.
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Hey Arthur,
if you buy a Masso G3 Touch directly at the Masso shop, then…
Just don’t forget that a Masso G3 Touch directly bought at the Masso shop comes without pöwer supply, without spindle connector, without any stepper motor drivers, and without a relay box (these things are all included in a Onefinity Elite Series machine, or in the Upgrade-to-Elite kit).
See also
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I have now been given a taste of the tremendous usefulness of the OneFinity Forum.
You all have given more than a headful of information on how the Machinist can meet my current needs and positive advice on the possibilities for refits that may be needed to fulfill my imagined aspirations,
Clearly I now need to investigate the suggestions and links supplied to better understand the technical aspects of all this.
Thank you all for your contributions.
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The Masso controller doesn’t need closed loop servo motors. The open loop steppers will work just fine. All you need to do is add a driver for each motor. Not sure where you live but in the US a driver is very cheap. I paid about $50 for a pro series stepper and driver from Steppersonline for my rotary.
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Hey Alex, hey Arthur @ArtPetch,
There is one linked in my post above:
I note that one difference between the x-50 and the Pro is an increase in the torque of the stepper motors. Is this so there is less likelihood of loosing a step and one way of compensating for not being able to use closed-loop steppers with the OneFinity Controller? Is this effective? Does it practically obviate the need for a Masso controller that can have closed-loop stepper motors?
Hey Arthur,
the conditions under which stepper motors work reliably, both open- and closed loop, is depending on the mechanical load. If the motors are sized to fit the expected load, you will not loose steps. On the other hand, if you overload them, the closed-loop stepper will not always be a real advantage. A closed loop stepper is a stepper with a glass encoder disc that feeds a closed-loop controller. If the steps sent to the motor deviates more than a certain amount, this closed-loop controller signals an error to the CNC controller wich can then stop the g-code program. But the amount of deviation between steps sent and sensed is relatively high before the error is triggered. The closed-loop controller gets a chance to try to keep up. Usually it takes time until the controller uses the incoming motor error to stop the entire machine. So if you encounter, let’s say, a very hard knothole that overloads the stepper so much that it looses its position, usually you can’t avoid the bit breakage anyway. The difference is if the deviation between steps received by the motor and sensed by its encoder is too big, an error is triggered, while with an open-loop stepper it is not, so the machine continues with a wrong position and may ruin more of your blank. But this is just an example. Usually knotholes rather make bits break than overloading the stepper, and a bit break is nothing a closed-loop stepper can sense.
So if you size your steppers strong enough for the expected application, usually you don’t loose steps, but closed-loop steppers are steppers too in the end, so they have the same speed and torque limitation than open-loop steppers. But the stronger PRO steppers reduce the risk to mechanically overload the steppers in any case, compared to the weaker X-50 steppers.
Usually you can try to mechanically overload a machine’s steppers if you select a much too high feedrate, depth of cut, stepover and ramp down with too big bit diameter and very hard workpiece. But usually the first thing that is to expect is that the bit breaks then.
The other thing that influence the mechanicial load limits is the ball screw pitch. For the older Z-16 assembly with its 1004 ball screw a small motor was enough to move a heavy spindle while the steeper pitch of the Z-20 assembly requires a stronger motor with more torque.
I think in this forum if steps were lost the cause was usually not mechanically overload but EMI due to non-shielded cables, unsuited cables like the “curly Z” cable or missing connector’s strain relief on old X-50 and Original Series, or the unsuited tin-plated Molex-Amphenol connectors that are not made for external connections (instead of using industrial circular gold-plated connectors) (more info here. Note that the PRO Series now have the 30 mm drag chains from the Elite, while all machines still have non-shielded cables with Molex/Amphenol connectors with tin-plated contacts)
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Because of what I have been learning I am able to see that what you are saying about the mechanical aspects of the CNC machine conform with what I have been learning to understand.
Keeping with the mechanical for a moment, does it make sense therefore that before giving up on the Pro series and moving to the Elite series out of concern for missed steps one would be make sense to first try using a more powerful spindle: for example moving from a trim router to a PwnCNC-type spindle (whatever that kind of spindle is called)?
I am interested in learning about the EMI issues, especially since a friend of mine experienced that with his CNC setup. Thanks for those links, I will follow them.
Hey Arthur,
as I said earlier, using such a powerful and solid CNC machine like the Onefinity machines with a hand trim router that is slowed down by the load, that can not deliver torque and speed at the same time, that looses its warranty in the moment that you mount it into a CNC machine (Makita stated), that has no ER collets so will have issues with bit position moving, that is extremely weak compared to a spindle, and may burn your workshop down if you overload it, seems just as a bad joke. This is no variant that I would ever consider, so I cannot answer your question.
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Suggesting that the trim router “will have issues with bit position moving“, says it all for me.
Well not quite all, my search for a CNC comes after rebuilding my studio that was severely damaged by fire. Need I add that your suggestion that trim router use in powerful CNCs can cause fires is also a VERY significant observation.
CNC fires are not unheard of as a recent IDC Woodcraft YouTube video also suggests https://youtu.be/3w8Jvi6qmN0?si=HyIRYbVE1Xyo0g_Z.
Hey Arthur,
There exist however Makita hand trim router clones that have real ER collets.
A burning Makita hand trim router is a popular topic in this forum 
Be careful if looking to buy one of those. For instance, the Lowes “CNC ready with ER-11 collet support” is a hair larger than the Makita due to an extrusion in the housing that causes it not to fit into the standard Z holder.