# Speeds & Feeds



## grepper (Feb 29, 2016)

Crap.  Back to square one.

I did a bunch of reading & YouTubeulating.  I _was_ thinking... go real slow, take very shallow cuts and I can't go wrong.  Seemed to make sense.  But I guess I was laboring under a delusion.
In fact, apparently that can cause a variety of problems like overheating, bad surfaces, shortened tool life, etc.

Do I need to get G-Wizard?  A little pricey @ $80/year.

Just at the onset I have way too many questions like, what about drilling, boring, how deep a cut? What does it mean with a tinker toy 1/2 hp mini lathe with a top speed of 2500 rpm? 

Once again I find myself clueless with a lot to learn.

ANY advice, suggestions, info on stuff like do I need G-Wizard or some ilk would really be appreciated.


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## Al-Hala (Feb 29, 2016)

Yup. Too slow or too little chipload, rub the tool into oblivion or run into chip thinning. Too fast, and the unit melts and or breaks. The calculations can be done by hand, or you can use a calculator tool such as G-Wizard or FS Wizard (has a web version). 

G-wizard after one year subscription reverts to hobby use; meaning any spindle under or at 1HP is still allowed: 1 HP for life, unlimited HP for one year. G-Wizard takes into account stickout, materials, HP limiting, deflection, and several other parameters that are tedious to spreadsheet. Even with a calculator, fine tuning can and should be done. The basic requirement is knowing the tool chipload (how much material is carried away by each cutting edge). Turning, the chipload will depend on a the feed in surface feet per minute, but when the diameter goes down or up, the spindle has to speed up or down to maintain the same SFPM. 

Another point to keep in mind when looking at Feeds and Speeds posted around the web on professional forums and or tooling sites: these are usually for production level material removal rates (MRR) on machines that weigh thousands of pounds, run multiple horsepower spindles and operate under the time-is-money-above-all-else rule of production machining, so take them with a grain of salt. 

*Basic Operations*
To give you some examples of the parameters with drilling, Feeds and Speeds still apply, plus there are restrictions on drilling depth vs. drill diameter. Below a certain depth, the standard twist should be replaced with a parabolic type. Over a certain depth, peck drilling should be performed (which retracts the drill to clear the flutes and hole). Drilling certain materials requires changing the cutting angle of the drill tip, as does thin materials.

Examples with boring, account for the tool deflection (last cut should be run with no change in diameter to remove the spring in the tool).

Start with simple machining first, getting used to how the machine cuts, sounds. The operational envelope is determined by the machine, the material, the rigidity of the tool, speed of the spindle, run-out, cutting geometry, all items that generally can be ball parked, but then need fine tuning for specific situations and your machine.  Get some aluminum, suitable cutting tools, and experiment. Listen, smell, feel the machine. Adjust speeds and feeds up and down and get sensory feedback on what is going on, you will quickly get a feel for it. 

*Resources*
Here are some good starting places:
Stanford University Terminology: a PDF explaining some of the basic lathe terminology.
Little Machine Shop Calculator: Milling, Drilling, Turning
Little Machine Shop Cutting Speeds: Charts for same
Machinery Handbook:* The* bible with 29 editions from 1914 to 2012. Pricey, but used and other copies exist. Think of it as the World Wide Web of machining in a book (with *over 2700+* pages, I feel safe in stating that). FAR more than you will need anytime soon. For example, from page 975 to 1264 in the 28th edition contains: Cutting Speeds and Feeds, tables, estimating speeds and machining power, cutting fluids, nonferrous metals and non-metallic materials, machine tooling accuracy.
Fundamentals of Machine Tools: Section 7-5 has a good description and suggestions for feeds and speeds for boring.
Virtual Machine Shop: Has several articles and some animation about basic topics. HERE is the section on boring, the section on drilling.
Mini-Lathe.com: long running site with a lot of information on the various small lathes. Here is Drilling, Turning, 
An enthusiasts beginner list: he is a native Japanese speaker, and some of his english transliterations are odd, but there are pictures enough. Drilling, Basic Lathe Operations


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## wrat (Feb 29, 2016)

I suppose there are many sources of info these days, but I'm old skool.

Machinery Handbook.  That's all you need.  Get one, cuddle up with it, and get familiar.  You'll have a long-term relationship.  The only time i worry about deviating is when using insert tooling, and then i only deviate based on insert manufacturer suggestions.  I got mine for $10.  But yes, new, they're like buying college textbooks.

Another good thing about a copy of MH is that it covers so much, you'll actually get new ideas.  I remember flipping through mine saying, "wait, you mean i can do THAT?"  Of course, this will lead to buying more tooling, but why forestall the inevitable?

Every material has a different cutting setup.  Aluminum is a nice setup material because you can't hardly go too fast (if your machine is rigid enough).  Titanium, or anything high in nickel, requires much closer attention.  The numbers don't lie and are based on countless hours of experience and repeatable research. 

Obviously, there's always "that one guy" that did it "that one time" and had unprecedented results that went on to write about his success.  Good for him.  However, those can be expensive rainbows to pursue.  I tend to stick to the conservative tried and true these days.  If you can get that data online, great, but I tend to prefer a book, specifically, THE book:  Machinery Handbook.


Wrat


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## TomS (Feb 29, 2016)

Al-Hala did a good job of explaining the preponderance of information that is available and how it is applied.  But not all of it relates to what we are trying to accomplish with our hobby machines.  I looked at many tool manufacturer websites and came away confused by the inconsistent recommendations.  My fall back reference is Machinery Handbook.  It hasn't let me down yet but that's not to say I've quit looking for a better source.  IMHO G-Wizard may be a wonderful tool but at $80/year it's not on my list of "need to have" tools.

Tom S


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## grepper (Feb 29, 2016)

Wow!  *The* Machinery Handbook, eh?  Sounds like the utmost, adamantine reverence for that tome.  Well then, roger that.  Wilco.

I would think having the speed & feed stuff integrated right into the CAM software would be cool.  For whatever reason I have not seen that.  Probably too complicated or too many variations or whatever to effectively implement.

Is there any pill I could swallow, or possibly balmy salve I might apply at bedtime which would provide ten years of milling experience whilst I slept?


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## grepper (Feb 29, 2016)

wrat said:


> Of course, this will lead to buying more tooling, but why forestall the inevitable?


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## JimDawson (Feb 29, 2016)

Material removal rate is limited by spindle HP and machine rigidity.  A little experience and experimentation is the best way to optimize the feeds and speeds for your machine.  Start slow and work your way up.  On a small machine the tendency is to feed too slow, this can cause the tool to rub rather than cut, which can dull the tool rather quickly.  Running the spindle too slow is really not a problem as long as the feed rate is adjusted.  Normal chip load is 0.001 to 0.004 per tooth on a light machine.  I actually measure the chips being cut to adjust the feed on the fly.  You can hear/feel when the machine is happy.  A little math will give you the starting point.

Start out with cheap endmills, you will dull some quickly and break others until you gain some experience.  

I think you will quickly figure out what works best for your machine.
.
.


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## dlane (Feb 29, 2016)

Is the machinery handbook 29th edition the best one for manual machining ?.
Dose it explain chip loads and nesasery fundamentals in plain English ?.
Best place to get one ?.
Ied like to get a little longer life from end mills
Thanks
: Jim that's kinda how I've been going at it, .002-.005 chip , dose that apply to carbide tooling also ?.


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## grepper (Feb 29, 2016)

When squaring the side of a block for example, how much of the side of the tool is used?  Maybe depth of cut is what I'm asking, but that does not sound quite right for milling the side of a piece.

Maybe it will become clear once I understand more, but I'm not sure how that relates to feed, speed and chip load.


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## grepper (Feb 29, 2016)

Looks like the name is actually Machinery's Handbook.  Pricey.  Hardcover only.  About $100.  Geeze.


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## Jim_Hbar (Feb 29, 2016)

grepper said:


> Wow! *The* Machinery Handbook, eh?



x2 What the others have said, except with one correction - the book's title is "*Machinery's Handbook*" and it's published by Industrial Press. 
The classic version is is 5 x 7 1/4" and almost 3 inches thick..  Easier to read formats are available now

EDIT - you posted while I was typing... 
EBAY is a good source - I have a #18 and a #27 from there..  The information doesn't go obsolete.


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## grepper (Feb 29, 2016)

Read the reviews on the Machinery's Handbook 29th edition.  Apparently early printings had poor quality paper, ink smudging, ink bleed through, and the paper was so thin that printing on the other side of the pages was so visible as to make the book very difficult if not impossible to read.  Many returned as ususable.

Paper quality was improved in later printings, but opposite side of page printing is still visible through the page.  Search around and you can find pictures of the problem.

Folks are saying get the 28th edition instead, but the 29th is claimed to be better organized and hence more useful.

Or, I guess the 29th is available on CD ROM.  I think for something like that I would prefer a book.

I find all that to be ridiculous.  The printing press was invented around 1440 BC.  It's now 2016.  One would think...


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## JimDawson (Feb 29, 2016)

grepper said:


> When squaring the side of a block for example, how much of the side of the tool is used?  Maybe depth of cut is what I'm asking, but that does not sound quite right for milling the side of a piece.
> 
> Maybe it will become clear once I understand more, but I'm not sure how that relates to feed, speed and chip load.



Material removal rates are measured in cubic inches per minute (or CC/min in metric units).    If you have a 50,000 lb machine and a 50HP spindle, the limiting factor is the tool bits, on machines that we normally work with the limiting factors are spindle HP and machine rigidity.

You can use the full cutting length of the tool.  The ''stepover'' is limited by the machine and the rigidity of the tool.  A full stepover is normally 40% of the tool diameter.  I normally leave 0.005 to 0.010 for a finish cut, and make the finish cut at full depth.  Less stepover is perfectly acceptable as long as the feed rate is maintained.  When cutting a slot, for smaller tools, you are normally limited to 2x the diameter of the tool because the tool will tend to walk sideways.

Normally when squaring a block, I will face mill all six sides if possible.
.
.


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## grepper (Feb 29, 2016)

Thanks Jim.  I obviously have a lot to learn.


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## JimDawson (Feb 29, 2016)

I have been doing this for about 50 years and I still learn everyday  I just make fewer mistakes than I used to.  Every time there is an OOPS, you learn what doesn't work


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## dlane (Feb 29, 2016)

Just ordered Machinery's handbook, $70. Free shipping 25% off 
Enco promo codes lpyr25 - lpyrff


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## jbolt (Feb 29, 2016)

After using the trail of G-Wizard I decided to purchase the full licence when it was on sale. The current pricing of $129 for 3 years and unlimited for life for 3 hp and under is a good value. He is always making improvements and upgrades are free for life.

I have been very happy with the software. I like that I can customize each machine profile based on actual usage and setup tool profiles. Even though my mill has a 2 hp motor due to the size and rigidity it behaves more like a 1.5 hp mill (in G-Wizard). Definitely has sped up my run times and I have only broken one cutter but that was a CAM error on my part. 

Another thing to consider is coolant and chip evacuation.


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## Bob Korves (Feb 29, 2016)

There are lots of relatively inexpensive options here:
http://www.amazon.com/s/ref=nb_sb_s...achinery's+handbook&sprefix=machinery,aps,254
for Machinery's Handbook.  Be careful of what you are buying, you want the handbook, not the pocket companion or other supplements.  There are large and standard (pretty small) print versions.  Older editions are quite usable.  I have the 22nd edition, 1985.  Any of the editions will be useful to the home machinist.  The older ones are better for manual machines and cover archaic standards better, the newer versions have much better metric system support and cover the latest tooling and methods.   They all cover the basics a machinist needs to know.  Just get one, any of them, and you will be good to go.  I put mine in the bathroom and went through it page by page, cover to cover, over about a year.  That gave me a good idea what is in there.


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## dlane (Feb 29, 2016)

I ordered the large print version, also the machinist calculator


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## Al-Hala (Feb 29, 2016)

wrat said:


> I suppose there are many sources of info these days, but I'm old skool.
> 
> Machinery Handbook.  That's all you need.  Get one, cuddle up with it, and get familiar.
> 
> Wrat





TomS said:


> My fall back reference is Machinery Handbook.  It hasn't let me down yet but that's not to say I've quit looking for a better source.
> 
> Tom S



I concur with Wrat (I had a parallel experience to yours; I spent hours in the book learning new tricks) and Tom; but given how much of a firehose you have been drinking from so far, I thought throwing that at you as a reference right off would be trying to learn about medicine from reading a pharma catalog; so many unfamiliar terms and diagrams.


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## grepper (Feb 29, 2016)

Bob Korves said:


> The older ones are better for manual machines and cover archaic standards better, the newer versions have much better metric system support and cover the latest tooling and methods.



By "newer versions" what do you mean?  28 and 29?  26 and up?

Holy crap!  I'm going to have to reinforce my coffee table!  At least I live withing 10 miles of a freight terminal.
At least an evening's light read, eh?


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## Bob Korves (Feb 29, 2016)

grepper said:


> By "newer versions" what do you mean?  28 and 29?  26 and up?


The manual changes gradually, leaving out stuff that is little used any more, and at the same time adding new technology and techniques.  Basic stuff like all the charts for making a gear will be in all the manuals.  If you are into CNC, you will not find it in the older manuals because it did not exist then.  If you are looking for information on a clapper box for a shaper, go to an old manual...
Again, all of the manuals have the general data you need to do basic and advanced machinist work.


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## TomS (Feb 29, 2016)

grepper said:


> Read the reviews on the Machinery's Handbook 29th edition.  Apparently early printings had poor quality paper, ink smudging, ink bleed through, and the paper was so thin that printing on the other side of the pages was so visible as to make the book very difficult if not impossible to read.  Many returned as ususable.
> 
> Paper quality was improved in later printings, but opposite side of page printing is still visible through the page.  Search around and you can find pictures of the problem.
> 
> ...



I think mine is the 17th edition or whatever edition was selling in the early seventies when I was an apprentice.  Oh Geez!!  Just realized that was over 40 years ago.

Tom S


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## dlane (Feb 29, 2016)

I bought a new one and hopping for the best ,,as long as it's not Chi !.


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## Wreck™Wreck (Mar 5, 2016)

grepper said:


> Wow!  *The* Machinery Handbook, eh?  Sounds like the utmost, adamantine reverence for that tome.  Well then, roger that.  Wilco.
> 
> I would think having the speed & feed stuff integrated right into the CAM software would be cool.  For whatever reason I have not seen that.  Probably too complicated or too many variations or whatever to effectively implement.



Some software does yet it is unlikely that you want to spend 4-5 times the cost of your entire machine to aquire it.


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## wrat (Mar 7, 2016)

Bob Korves said:


> The manual changes gradually, leaving out stuff that is little used any more





Bob Korves said:


> If you are looking for information on a clapper box for a shaper, go to an old manual...


Exactly.

I have a 14th Edition.  Acquired in the mid 1970s.

Why so old?  well first-off because i HAVE it and don't need to spend for the latest "operating system" of a machine.  But secondly, my main machine is from the 1950s, so it's a good fit.  Little has changed except insert tooling and those vendors provide plenty of info for their specific products.

With my book, i could run my shop on leather belts.  It has stitching procedures and sizing for exactly that.  I won't, of course, but it's in there.  I think the most exotic, experimental technology it mentions is the hydraulic tracer head.  Heady stuff, eh?

Wrat


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## grepper (Mar 8, 2016)

Wow!  Leather belts.  You have to admit, that pretty special.   Who  knows, after the zombie apocalypse...


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## wrat (Mar 8, 2016)

grepper said:


> Wow!  Leather belts.  You have to admit, that pretty special.   Who  knows, after the zombie apocalypse...


Do zombies eat cattle? Dunno... maybe there'll be leather.

Wrat


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## RonGinger (Mar 8, 2016)

There are two wizards available for Mach- for Mach3 there is the Add-ons for Mill for $50 and there is the NfsMill  package, for Mach4 for $75 but it is a standalone windows program that does not require Mach. Both can be used to generate Gcode for some failry complex jobs, combining common shapes and drilling patterns. Both calculate appropriate feeds and speeds for many common materials, and each let you edit the material table as you decide what feeds are appropriate for you machine. Both are one time license fees with no time limit.

In the name of disclosure I wrote and support both sets of wizards. I am currently working on the lathe wizards to go with the LMS lathe conversionI I am working on for TheCNCworksop.com coming in June


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