Hi, a 50 y/o newb here.
I'm totally lost with a weird problem in my aluminum parts - hoping someone with experience can help me.
I have a Probotix Nebula router with DWP611 Spindle, which I use a lot to route wood and plastic. Coupled with RhinoCAM Mill - great combo.
I recently had to run a series of cuts on 1/4" Aluminum ... And spending days trying to figure out this weird issue I'm having with my cuts.
I know the min speed of 16000 is too high for aluminum, but that's all I have. My part, measuring about 6" at its longest, has some holes, some pockets and the last operation is cutting a piece out of the bar - that's where I hit a wall ...
I make 1mm (0.04 inch) passes at 800mm/min (32IPM) to cut the piece away (5 bridges to keep it in place). The first 90% of the depth - everything is fine. All passes are perfectly aligned on top of each other. I spray WD40, remove chips, etc. Then all of a sudden once I get to the last two passes (esp the last one!), my endmill engages the part at full height (2x diameter of the tool) near the end of each circle. That is - pass starts fine near the entry point - then starts biting into the part at full height.
Here is the part. I have succeeded cutting a couple, with part fixed in different orientation, and the picture is exactly the same each time. I get a TON of hair-like chips on the last two passes, and the tool screams bloody murder
* RhinoCAM shows toolpaths are perfectly aligned.
* I'm using conventional milling
* Stock is screwed securely to the spoilboard
* I tried positioning the part vertical or horizontal (thought it might be the CNC backlash) - but same result
* I cut a channel about 1mm wider than the toll width (so, two passes per level with 1mm (0.04") stepover), thinking it was chip clearance problem (it is not)
neddless to say - I end up breaking $30 carbide single-flute tools.
Here is an end part for reference
How can this be explained? Will climb milling help? (I dont see how it would) Bug in RhnoCAM? Some weird physics going on on the last two passes?
Really appreciate any thoughts on this!