sidesh0wb0b
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again, i run a 51d with cap strategies and TD burs. no issues. my table isnt as stable as i would like, but it seems to be stable enough for 99.9% of what im doingif you are experiencing poor performance from your tools, there are several things to check. 1. tool runout. 2. deflection. 3. vibration. 4. mill overpower.
tool runout means the amount of physical deformity the tool holder has in the chuck. if its not held straight, it wont cut straight!
Deflection is how much the tool turns into banana shape during milling. it could be that the cap tools allow for more flex in the tool than Ron's tools do. though i make no claims to know how banana shaped Ron's tool is. i imagine slight curve to the left...
Vibration can harm your machine long term. if your mill is on a wooden table that seems to wobble when its milling, consider adding leg supports to stop that. you want it to stay as rigid as possible because the vibration is inertia that isn't being absorbed, just deflected. this inertia is likely caused by making the machine go too fast, perfect segue into Mill Overpower; each spindle can be shown to have a certain amount of power at 100RPM, and a different amount of power at 30 000 RPM.and for the most part a linear transition through the power, tapering off the higher you go. beyond a certain point (different for every spindle) the power required to get more rpm starts growing exponentially. this means the curve does have an upper limit, based on input power. no, in zirconia manufacturing this power curve doesnt really mean a lot, other than to say the power of the spindle if it is going too fast will be detrimental to your tools and your crowns. in hard material manufacturing (i.e. if you were using a mill to cut stainless steel crowns, or titanium abutments) this power curve observation is critical for longevity sake. you want to know the machine isn't stable when it draws all 20amps from the wall, and act accordingly. not only limiting the input draw, but the output power as well, because you don't want to calculate that the maximum cutting speed of a Kennametal tool might be 29k RPM, but if your tool holders are only rated for 20k, you'll instantly know you have to back off from maximum or the runout will kill your tools. hence, knowingly and purposefully underpowering your process to preserve the life of the machine.
