Speed and Feed

[kdoney]

What speed and feed are you running?

[lakeside]

that all depends on what I'm ruuning and what type of tool is cutting so it kind of a wide open queistion that can't be answered without a more detailed question

[pbreed]

Given:

Material, (aluminum, steel, Stainless....)
Cutter diameter
Number of flutes
Cutting horsepower availible....

What is the desired speed and feed?

There should be some kind of formula?

The speed and feed for a 1/4 Hp taig will not be
the same as the speed and feed for a 20Hp HAAS.

I've always done this by tiral and error, but there should be a better way.

[Neil_J]

Originally Posted by pbreed Given: Material, (aluminum, steel, Stainless....) Cutter diameter Number of flutes Cutting horsepower availible.... What is the desired speed and feed? There should be some kind of formula? The speed and feed for a 1/4 Hp taig will not be the same as the speed and feed for a 20Hp HAAS. I've always done this by tiral and error, but there should be a better way.

You can look them up in the Machinery's Handbook (page 1022-1074 in mine). Buy/borrow/steal one now if you don't already own it.

Most all CAM programs will calculate them for you based on cutter dia. / material, etc..

You can also buy a little slide rule paper thing through some suppliers like Enco... Nice to keep in the tool box.

[lakeside]

save the $80 on the machinist handbook and spend $100 on this software it ME PRO well worth it
http://www.mrainey.freeservers.com/

[dertsap]

ask the manufacurer what their recommended surface feet is , literature doesn t necessarly give the proper speeds and feeds for a given cutter , for example you look at a box of sandvik inserts they have a recommended surface feet , sandvik has a new calculation software that breaks it down to insert type , material type , cutter dia , # teeth , depth of cut and tool engagement , then it is broken down to cubic inches per minute removal , turns out the surface feet per minute is up to four times what is on the box , sfm will soon enough be a thing of the past , i was cutting 1018 mild steel at 7800 rpm at a min of 120 in/min ,with a 3/4"' 3 flt at a .1 depth , and that was consevative , funny thing is we presearved a better insert life and , doubled to tripled some production runs
, company i work at now refuses to recognize this , as most companies are ,
tools are better , machines are better

[lakeside]

all feeds and speed give from any sorce are just starting piont you alway have to adjust for the unknow rigdedty part holder ect.

[dertsap]

normally the manfacturer specs are the best , their specs are normaly geared to optimal professional operations , they guy at home really does have to look at his own obvious capaibilities

[lakeside]

even in a professional aplication the info is only a starting piont but a good starting piont I've been machining for over 25 years and can tell that one fadal will run at one speed and another fadal will run at a difernced speed due to many fact like spindle bearing wear ect.

[dertsap]

like i said earlier on the speeds i was running at were conservative compared to what they recommend , i saw a lot of seasoned machinists drop their jaw to the floor to see those machines run like that , my point was old school is OLD school , of course you take every case for itself , this is what makes a professional a professional

[lakeside]

a true professional make Quality not speed if you machine can handle the feed that great but I've see machine that are 5 years old that are junk and no I'm not from the old school but have a lot of skill I love to see some of the cnc guys trying to run anything with out a controller I’ve made propellers for aircraft carriers (23 foot dia.) down to micro tools in the end you cut as fast as you can don’t try to say a real professional is measure if he follows the manufacture spec. They are starting point and I would never say that someone from the old school is any less a professional than someone who know how to run a software program a set up a cnc it not rocket science it practice

[kdoney]

All, first of all thanks for reading. I'm not saying that your comments have not been helpful but I know it depends on what you are cutting and the tooling. I was wondering, for a normal chinese mini mill, what feeds do you get using a specified tool, cutting a specified workpiece metal, with or without coolant. I wanted to get a feeling to see if the home-made cnc mill I made with a chinese mini mill head should be able to cut faster than I have been pushing it. I seem to be able to cut about .005 per pass on 6061 at 10 ipm with a 45 degree carbide bit 2 flute high helix, no coolant, without much complaint but I want to push it past the normal expected from a standard mini mill. In other words, if someone is cutting .010 at 20ipm on a standard chinese mini mill with the 4/5 hp motor I would go that way and push it until I either broke it or exceeded the standard. I don't want to keep on pushing beyond a reasonable expectation. But I don't know what a reasonable expectation is.