RDOC, ADOC, IPM, IPT, oh my... Help!

A lot of beginners assume that you have to obey the speed/feed charts exactly. You don't, especially when cutting steel. As Mikey pointed out, the charts are often intended for maximum production in an industrial environment with big, rigid machines where time is money.
Mark
 
JimDawson said:
Feel is all you really have to go by when operating manually (or in many cases CNC for that matter). There really is no right or wrong, but rather what works for your machine and job. If your machine is happy, then all is good. :)
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Willy, I've been mulling this "feel" thing over. I just milled some mild steel and aluminum to organize my thoughts on this. I've said in the past that I feed fast enough (that is, I turn the handwheel fast enough) to feel a slight resistance as the end mill cuts through the material, and then I try to maintain that rate of feed. This is as close to what I "feel" as I can get. As I also said, I've pushed end mills to the breaking point and it requires a LOT more feed and force to break one VS feeding it so that it cuts without rubbing. There is also a sound when the end mill is cutting happily; that I cannot describe.

Some end mills cut with less resistance to feed than others; depends on the geometry, the material, your cutting conditions, coolant, etc. Regardless of this, I feed by feel and my end mills cut well and seem to live a good long life.

Manual guys like us learn to listen to and feel our machines, and we respond to the cut. We learn what this is like when the machine is happy and when it is not, and we will sense when it is not in an instant. I like that about manual hobby machines. For myself, I will leave the MMR and light cuts with super-fast feeds to the CNC guys. I'm sure it lights their fire to do that but for me, I prefer to feel the machine cut well. I have an X-axis powerfeed on the mill but I often feed manually, just because I like to stay in touch with how the machine feels as it cuts. I suppose that this is silly in this day and age but as Jim said, it is really all a manual guy has.

One other thing crossed my mind as I was cutting some mild steel. I use an ER chuck to hold the end mills. That feels different from using an R8 collet or end mill holder. The ER feels more solid and has less vibration.

Not sure if this will help. Maybe the other guys will chime in with their methods.
 
Wonderful Mikey! Not just what you stated but actually getting in tune with the question like that.
Not to go off on a Tangent but I have to ask you more about the er style since I know we have similar mills. I' ve always felt that the r8 with less stickout and one less connector was always more rigid with the machine taper. I am not challenging you at all. Maybe it is something I should consider. I ve always thought the advantage of the ER collet was for quick change and the range it offers per collet being able to stray from the nominal size somewhat not like the r8.
Hmmmm!
 
Actually, that's a fair question, Mark. ER Chucks actually dampen vibration better than other tool holding methods. They are also more accurate than an R8 collet and have more gripping surface. They are not faster to use but their other advantages make them a better option for me. I really can feel the difference but maybe it's just me.
 
I ve definetly liked them with larger endmills for not getting pulled out like the r8 being pushed.
 
mikey said:
Willy, I've been mulling this "feel" thing over. I just milled some mild steel and aluminum to organize my thoughts on this. I've said in the past that I feed fast enough (that is, I turn the handwheel fast enough) to feel a slight resistance as the end mill cuts through the material, and then I try to maintain that rate of feed. This is as close to what I "feel" as I can get. As I also said, I've pushed end mills to the breaking point and it requires a LOT more feed and force to break one VS feeding it so that it cuts without rubbing. There is also a sound when the end mill is cutting happily; that I cannot describe.

Some end mills cut with less resistance to feed than others; depends on the geometry, the material, your cutting conditions, coolant, etc. Regardless of this, I feed by feel and my end mills cut well and seem to live a good long life.

Manual guys like us learn to listen to and feel our machines, and we respond to the cut. We learn what this is like when the machine is happy and when it is not, and we will sense when it is not in an instant. I like that about manual hobby machines. For myself, I will leave the MMR and light cuts with super-fast feeds to the CNC guys. I'm sure it lights their fire to do that but for me, I prefer to feel the machine cut well. I have an X-axis powerfeed on the mill but I often feed manually, just because I like to stay in touch with how the machine feels as it cuts. I suppose that this is silly in this day and age but as Jim said, it is really all a manual guy has.

One other thing crossed my mind as I was cutting some mild steel. I use an ER chuck to hold the end mills. That feels different from using an R8 collet or end mill holder. The ER feels more solid and has less vibration.

Not sure if this will help. Maybe the other guys will chime in with their methods.
Click to expand...
What does MMR stand for?
 
Mis-print, my fault. It is supposed to be MRR.
 
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