It would seem that the printer control board doesn't use a CH340 (see bottom of this answer) and therefore this answer should be ignored.
CH340 and OS X incompatibility
The reason your Mac might not see the printers could be down to the USB interface on the printer controller board.
If it is implemented by a CH340 (which is probably is, in order to reduce manufacturing costs) then, historically, MacBooks have a problem with the drivers for this device and its derivatives. That is to say, the OS has a problem - more specifically the device drivers used by the OS X kernel - as opposed to the hardware. There are a number of posts dealing with this problem, it is common on Arduino clones too, see here.
The third party drivers for the CH340(G) written for OS X are often poorly written and/or have shoddy documentation - although this opinion may be hotly debated, and I have no wish to expand upon.
If the USB interface, on the printer controller board, is implemented with an FTDI or a ATmega 16U2 then it will work fine. Unfortunately the solution is probably not to use the Mac and stick with the Lenovos (i.e. PC clone).
See the extensive answers to Can't connect Cura to my Anet A8 on OSX 10.11.6
As an aside, I gave up trying to buy/use cheap Arduino clones with a CH340(G), on a Mac long along, as it just wasn't worth the effort in trying to get the Mac to see it. I now ensure that either:
- I purchase a slightly more expensive Arduino which uses a 16U2 (the more pricey FTDI chip is more rarely used on boards these days, but can still be found). Obviously, you don't have that sort of luxury when selecting a 3D printer.
- I will use a PC instead, if the board has a CH340(G), or similar.
One possible solution
However, having said all of that, this issue may have been resolved in newer versions of OS X (post Mountain Lion, or thereabouts). This might provide a solution, Connect to ch340 on MacOS Mojave
remove all old drivers:
sudo rm -rf /Library/Extensions/usbserial.kext
sudo rm -rf /System/Library/Extensions/usb.kext
Now reboot the computer.
And then (very important, because it took me 10 cables to find the
right one) use a fully connected cable ;-)
Now I have these ports:
Important note: Clearly, deleting kernel drivers (also known as kernel extensions,
.kext) shouldn't be taken lightly. If you feel uncomfortable doing it, or don't know how to revert the process, by using a saved backup of the drivers, then please don't attempt this.
To back up the
kext (before deleting it as shown above):
sudo cp /Library/Extensions/usbserial.kext /Library/Extensions/usbserial.kext.bak
sudo cp /System/Library/Extensions/usb.kext /System/Library/Extensions/usb.kext.bak
To restore the
kext (after having deleted the kernel extension and then finding that it made no difference whatsoever):
sudo mv /Library/Extensions/usbserial.kext.bak /Library/Extensions/usbserial.kext
sudo mv /System/Library/Extensions/usb.kext.bak /System/Library/Extensions/usb.kext
Alternatively, instead of deleting the kernel drivers, you could just rename them to hide them, by adding
.bak to the filename, like so
sudo mv /Library/Extensions/usbserial.kext /Library/Extensions/usbserial.kext.bak
sudo mv /System/Library/Extensions/usb.kext /System/Library/Extensions/usb.kext.bak
Then reboot. Check the printer connects or not. If not, then just restore them using the same commands shown above - so you just end up removing the additional
.bak from the filename.
With respect to the quoted answer, I'm not entirely sure what is meant by a fully connected cable... There is a well-known issue that some USB charging cables - that look like normal USB cables - have only the power lines connected, and omit the data lines (again for cheapness), and it can be difficult to tell the two apart (usually by thickness, the thicker cables have more lines connected). Obviously, if the data lines are missing then the cable will not transfer data.
However, this usually applies only to cables with mini, or micro USB connectors, and usually doesn't apply to standard peripheral cables such as a USB-A to USB-B cable:
So, this issue should only arise for micro/mini USB connectors... it will depend upon your connector type.
We can't recommend particular makes or models of USB hubs as that is a shopping question, which is off-topic.
Analysis on the printer board
Makerbot appear to use the Mightyboard for the Replicator. INterestingly from the following two photos it would appear that a CH340(G) is not used, and the IC is in fact a 16U2.
Here is a photo of the board (image from MakerBot Replicator 2/2X Rev H Mightyboard – Official, OEM Board w/ 4 BotSteps):
The IC closest to the USB-B port would appear to be a 16U2:
- Its form is square like a 16U2 and not elongated like a CH340G
- It would appear to have an Atmel logo printed upon it.
This image (from MightyBoard Motherboard 3D Printer Dashboard), also suggests the a 16U2 is used:
All of which means that, if your printer(s) have this board, then your Mac should indeed connect to the printer.