Sherline CNC Mill

MakeICT has 2 Sherline type mills in the Electronics and Rapid Prototyping Lab which can be used. Both are CNC mills. Neither is directly branded Sherline, but the mills are almost certainly re-branded Sherline products.

Neither is ready for common usage, but both do work. They are capable of handling metals, including steel, unlike the V90 router in the Electronics Lab.

Black Mill

One (The one in the black case with cover) is on indefinite loan to MakeICT by a member, and is run by GRBL software on an arduino, along with pololu stepper drivers (DRV8825, specifically Pololu's page) It does need a computer to stream the G-Ccode to it. (Universal G-Code Sender is recommended.)

For information from Sherline, see here for an introduction: Sherline Vertical Mill Instructions as well as recommended speeds and feeds. Please note, that though it can handle metals, it is not going to be nearly as fast as the Tormach, because of the much greater power (approx 15x) of the Tormach, though both have similar rpms.

Safety

Due to the mill having much less power than say the Tormach, or the V90, it is safer to use. Please note, that the mill may still cause something to break, and throw small bits of metal, which could be initially moving at over 183mph with the normal head, and even faster with the air head! Always operate the mill with the cover down! Please also wear eye protection, as even with the cover in place, it may bounce around.

This mill has handles, and it can be used as a manual mill. It is not suggested to be used in that manner, as there is a larger manual mill in the Metal shop. Additionally, to operate in this manner, the cover must be up.

Rough settings

The axis are controlled by steppers, connected to 1/4"-20 (1.27mm/revolution) threaded rod. The stepper motors connect to the stepper drivers through DIN-5 connectors, with Pins 1/2 as one coil and Pins 4/5 into the other coil, Pin 3 is not used. The microstepping settings are determined by the connections on the board.

The limit switches are controlled by a 15-pin, double row connector. Counting from left to right, row 1, then left to right, row 2, pin 15 is a common pin, the other switches (X, Y, Z limit switches, and the cover closed) are on pins 2 (Believed to be Z), 4(Y), 5(X) and 11 (believed to be cover).

The spindle is controlled manually, via a power switch, a 2 place belt drive pully and a potentiometer controlling speed. Maximum speed is approximately, 2800rpm.

Materials possible: Plastics Wood (Preferably on the V90 Router, due to the cleanup required, and use of oil for metals on the machine.) Circuit boards (Suggested to use the PCB Mill, which is setup specifically for milling PCBs.) Aluminum Steel Cast Iron Stainless steel

Checklist

Before running code, please make sure feed rates are correct. 1. Zeroed 2. Tool clamps clear 3. Any obstructions on X-Y (Will it hit the end of the enclosure.) 4. Drawbar tightened 5. Spindle speed set correctly? 6. Lubricant handy if 7. Anything on the enclosure 8. Control board in a secure location. 9. Power on to spindle. 10. Power on the motors. 11. Send file.

Blue Mill

The other (blue) mill, is controlled via a computer, and matches much of the general specifications, but uses a dedicated computer to control it.