I¡¯m sure Amana or Onsrud will have cutting data on their cutters for wood. You don¡¯t have enough rpm to run the theoretical amounts for wood, none of us do. I¡¯ll say it again, what¡¯s the problem with running slower? You get less burning, better finishes and less chatter.
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David,
My machine label says 50 Hz. I remember speaking to Felder about it and perhaps mentioned it here as well but was told it should be fine. I will check the motor label when I am in shop to see if it states RPM specific to Hz.
It is hard to find end mill info for wood. I found this for uncoated carbide (requiring lowest RPM). If wood equates to plastics than 3/4¡± bit equates to 4100 RPM. So I may be able to try end mills on my FD250 for larger dia. Not sure if they are produced in lengths needed for FD250.
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I know this is a much deeper subject.
Imran
On Jan 30, 2021, at 9:55 AM, David Kumm <
davekumm@...> wrote:
?
Given the FD is direct drive, I would think the speed is closer to 3400 in the 60 hz market.? Generally you can overspeed a 2 pole motor to about 90 hz assuming the motor is decent quality.? Downside is that torque will be reduced because you aren't maintaining
the volts/hz ratio.? The benefit and need for higher speed is really for small diameter bits so the reduction in torque might not be a big deal.? 5/8" bits are not a great choice for more speed and less torque.
4 pole or 6 pole motors are good for higher hz and vector duty motors are good for something like 5000-6000 rpm or up to 240 hz.? When you do that you usually oversize the motor to compensate for the loss of torque on the high end.? You also need to realize
you may have way more torque on the low end than what the machine is designed for so care must be taken.?
Thank Brian for straightening me out on this years ago when we had a discussion here about Rong Fu mills.? Dave
After realizing that people have used end mills on their mortising attachment, I was curious if there is a way to increase the RPM of FD250. The bit on morticing attachment is likely running around 5000 RPM, whereas FD250 is around 3000 RPM.
This article says it can be done as long as motor does not exceed it¡¯s FLA, is not electrically overloaded and operating with it¡¯s mechanical design limits.
Anyone got an idea how much more speed might be possible?
Electrical parts can be measured but I have no clue on mechanical side of what margin might exist.
This may not result in anything meaningful but I like to learn. One thing leads to another ....
Imran
