ME 418 M8, M9, & M10 2014 Robert Peace firstname.lastname@example.org
M8 Before launching Mastercam for the 1st time: • Open Windows Explorer & Navigate to: • Computer Windows (C:) Users NSID Default • Copy my mcamx7 folder • H: My Documents • Paste my mcamx7 folder
M8 – Drawing in MasterCam • Things to Ensure: • Coordinates are: D+, Z (diameter and Z) • Units are Metric • Machine Type is Baxter Lathe (Operations Manager) • File Save location is H: drive (if it is left on C:, you won’t be able to access it). • If undo is unavailable, Esc the function and it will be available.
M8 – Stock Set-Up Chucking ~1/3 of finished length: 65/3 ~ 20 mm Total Length: 20+8.7+65+2 = 95.7 Round to 96.0 mm Facing pass allowance, after rounding = 2.3 mm Safety Clearance ~2mm, round to 1.7 mm Part-off Tool Important measurement: =8.7+65+2.3=75 mm B=3.0 mm Jaw Width = 47.3 mm W=4.0 mm Grip Length ~ 20 mm (technically 20.3 (29-8.7) Position along Axis, Z: -29.0 (20+8.7~29) ZW= 47.3+1.7+3+4=56.0 Origin
M8 – Tool paths First is Always a Facing Pass with tool ID#5 Leave stock behind for finishing passes. Always “From Tool” Reference points to ensure safe tool paths. Lead in/Lead out parameters for some tools are required. Cut-off tool is always tool ID#130 and in position 8.
(200,0) Cup Reference Points (D, Z) (58,55) (58,45) (58,38) (54,70) (54,30) (54,0) (54,41) Barstock (48,28) (48,0) (44,43) (42,50) (33,70) (38,32) (30,62.5) (18,70) (20,62.5) (20,40) (0,70) (0,40)
For M9 • A printed, dimensioned (METRIC) drawing of your work-piece. SEE PAGE 6 for Details. • A printed listing of all tools used, in sequence, maximum of 8 tools. • Draw your part in AutoCAD, as it is a smoother import than Solidworks. • Draw part to Full Scale. • Drawing already imported into MasterCam, and origin set (see page 68 of the lab manual). • All Roughing passes attempted in MasterCam. • Templates for set-up sheet, drawing and Job Card can be found on the ME 418 website.
For M9 • Design Considerations (see lab manual 6-9). • Maximum diameter = 50.8 mm • Maximum length <= 2.5* stock diameter • Keep the bar-stock as thick as possible close to the chuck for as long as possible. • Very small diameters can result in unstable work pieces and chattering (poor surface finish). • Design should include circular arcs and straight lines. • Tool #1 must be the reference tool – Tool ID#5 (T0501) • Tool #8 must be the part-off tool – Tool ID#130 (T13001) • Tool library is in the Lab Manual • Late Penalties & Marking Scheme supplied on pages 3-6 of the lab manual.
Work Piece Datum & Tool Change Positions, G50’s • If these are not correct, collisions or “Machining Air” can occur. • Says where the cutting edge is in space relative to the workpiece datum (Origin). • When a tool change occurs, the Turret does not move, but the coordinates X, Y change. • This is because the tools cutting edge is in a different location. • Description of calculations: Page 61 of lab manual • Values for “cup” example: Page 63
CNC Code Debugging • Unmodified Code found on page 56 • Debugging Tools: • MastercamBackplot • Shows tool path, rapid moves, tool and holder • Can be expanded (double blue triangles) to show coordinates D, Z, Y of leading edge of tool during run through, rapids and feeds different colors. • Can set to stop at any change in XYZ, (stop sign to right of progress bar). • Mastercam Simulation • Shows tool position using X, Y, Z coordinate system, not the coordinate system used in the drawing process. • X Z in drawing • Y Radius in drawing (even though we used diameter programing) • Z Y in drawing (always 0.0 for our case) • Plot.exe (similar to Backplot) • Custom made DOS program to assist with student code debugging. • Space.exe • Custom made DOS program to space out CNC code to assist with student debugging.
Due Before M10 • See Page 4-5 of lab manual. • Two weeks after M9: • Completed Mastercam file - digital • Completed CNC Set-up sheet – hard copy • Completed Engineer’s Drawing – hard copy • Work Piece Datum & Tool Change Position (G50’s) - digital • 3 School Days before M10: • Debugged CNC code – MUST have been run through SPACE.exe - digital • Any corrections to G50’s, drawing or set-up sheet. • Drawing and set-up sheet – hard copy (only if significant changes).