Im using fusion/hsm works (in solidworks). Im trying a 2 sided cut. My finished product is centered in the stock material (x long side and y short side). when i flip my part and cut the opposite side its off by approx 1/8" in the y direction. Of course the simulations look correct. Any ideas? I have physical stops along the blue surface on my waste board. My wcs is the same location (lower left corner for each side).
Couple of things come to mind. 1 - Most common issue with doing a two sided cut this way is your stock size is off. Being off a 1/16" in y would throw off the finished piece by 1/8" 2 - Are all other cuts accurate? Did you calibrate your motor steps? 3 - Dont do two sided cuts this way. Using locating pins cut into your stock eliminates this issue. There's a bunch of videos on how to do this, but here's one from ooznest:
FWIW, I frequently do two sided machining. This is the basic setup: Machine is set to do homing at startup so that the axes can be moved to a known position Tooling pin holes for 1/8" split pins are cut with the CNC in the spoilboard at regular intervals along the Y axis at the centre of available cutting width along the X axis A Macro was created to move the machine to the centre front tooling pin location This is the basic workflow*: Design the part in Fusion with the tooling holes spaced to engage with any two of the tooling pin holes in the spoilboard Create two Manufacturing Setups - one for each side. Cut the tooling holes when doing the first side Locate the WCS Origins in the Manufacturing Setups for each side at one of the tooling holes Depending on the geometry of the part and the relative location of the tooling holes to the edges of the part, decide which tooling holes will be used on the spoilboard Use the "Front Centre Pin" macro to move the machine to the foremost tooling pin location. If the foremost pin location for the machining origin needs to be farther along the Y axis, incrementally jog the machine to the appropriate pin position. Set X-Y Origin to this position and set Z origin as normal Mount the raw material to the machine in a suitable location Machine the first side Remove the material and install pins in the spoilboard at the required locations Locate the material on the pins and secure to machine the second side Comments: *Using this method, it is possible to cut blind tooling holes when machining the first side that are used only when the part is flipped to the second side. Arrange setups so that tooling holes do not come through the "good" side. Use small diameter pins. They are less intrusive and just as effective. Locate the tooling pin holes in material that will ultimately be removed if possible (e.g. locations of large holes in the final part). Use tabs when required to secure the material for machining the second side
