Cutting Speed and RPM on the Lathe and Mill

[@bubbadoolittle2812]

As far as a clear demonstration, this is the best and most straight forward on KZbin.!!!

[@haydensuperville1967]

Masterful Indeed!!.....

[@simpleman283]

I was reading the comments and Wow some people really do come straight from the classroom books and calculator in hand looking for someone to critique. As for the rest of us we do appreciate these helpful videos.

[@keithb4007]

This is by far one of the most informative to the point videos I have seen. I appreciate that you kept it simple and showed how it's done. I am new to metal turning and this is a fantastic jump off point!! Thank You!

[@pbc1951]

I copied your comment.... It was so good, so well written.... Thanks... Paul I am new at the Milling machine !!

[@freestyla101]

Yet another video that has taught me something I didn’t know in as many minutes as the number of other videos I’ve watched.

[@MyShopNotes]

I don't know how many times I have come back to this video. I am a hobbyist and don't use this every day, having these resources is great. I am grateful to you Tom and many others out there providing us this educational material.

[@TomsTechniques]

Steve S Thanks Steve. It's good to hear that the video is being used. Tom

[@CapnCrusty]

I know this is an old video but I just found it and I wanted to thank you for it because this one video has (I believe) solved my premature cutter wear problem. I've been running my tools at way too fast an rpm and have been wearing out end mills much too rapidly. I also am making normal sized chips in steel now instead of a bunch of tiny needles that I'm not sure I'll ever get out of my hands completely. Priceless info for me!

[@TomsTechniques]

Thanks, I'm glad to have you on board. As soon as I get my website up and running, the videos will be better organized and there will be project tutorials to help you learn even more. Tom

[@danmoreton1788]

I am new to using a lathe and mill and I am appreciative of all information that helps me to gain new skills. It was helpful when you showed the math that determined the relative rpm for various metals. Thank you!

[@TomsTechniques]

Hi Dan, I make these videos for guys like you. It's good to know they are appreciated. Tom

[@bobmorgan7913]

Hi I'm new to the hobby, just bought a mini mill. I worked in a machine shop, over 50 years ago. Always wanted my own machines, have a mini lathe. Enjoy watching all the. videos.

[@TomsTechniques]

It's a fun hobby, Bob. Thanks for watching. Tom

[@RalphRotten54]

The trusty HP reverse notation calculator...had one in college and still use 25 years later. Nice video. Thanks for sharing.

[@TomsTechniques]

+djhoosier Thanks. Bought it in the 80's and it's still going strong. Don't know what I'll do if it gives up the ghost. Tom

[@lowridingtrucks88]

To tell you the truth i was going to watch it later, but you made it easy to understand and i didn't want to stop watching it. Thank you for taking the time to share your knowledge. I also saw your "square up stock video" and i applied it at work and works great! Thank you Tom sincerely.

[@BrianBurns-x4r]

Im brand new at machining metals, including types of bits and their names, types of machines and purpose, and cutting speed rims. 64, and this knowledge is interesting as heck to me.

[@TomsTechniques]

@@BrianBurns-x4r Good to hear!

[@177BCardinal]

I've learned a great deal from these videos from Tom. I can now sharpen a lathe bit and run it at the right speed. I've had an old South Bend "Junior 9" for almost 50 years and it's high time I improved my skills. Thx Tom!

[@TomsTechniques]

Good to hear!

[@conkcat]

Thank you, very concise, to the point, very simple to understand. No stupid over loud or annoying background music or dramatic video shots. I am looking to make my own mill, but was unsure of max spindle speed I needed to do this, you have answered this question perfectly. Now I subscribe and look forward to watching your other videos Thank you sir.

[@TomsTechniques]

Thanks for watching. I'm considering building a gantry type CNC mill myself.

[@jimmilne19]

Second time through this one. Very informative. I also enjoyed Rex Walters' explanation in the comments which answered a question banging around in my head, "Why four?" Let the sleepy viewers fall asleep: we awake ones are interested in both the how and the why. I'm looking forward to a productive new year and you'll be a part of it. Thanks.

[@TomsTechniques]

Thanks Jim, glad you are enjoying the videos. Tom

[@ralphparker]

SFM =RPM * pi * dia (inches)/ 12. [12 inches per ft]. Pi is 3.141... or just round to 3. Circumference of bit = Pi * dia. so RPM = SFM * 12 / (3 * dia) or SFM * 4 / dia

[@ramirocortez6392]

Thank you sir ! I burnt up a 1/8 endmill today because my journeymen toolmaker told me to run at 800 rpm !???? Thanx again I am a apprentice toolmaker will be watching you're videos!!

[@TomsTechniques]

Not sure what you were machining, but 800 rpm is about a quarter the rpm you should have been using for mild steel. Was the material hardened by chance?

[@ramirocortez6392]

@@TomsTechniques no 8620 basically cold roll

[@Shift2Movies]

Tom, thank you very much for this tutorial. I'm sure I speak for many of us who have not commented.

[@ZappninLLP]

Thanks Tom, for this very basic and easily understandable explanation. There are a lot of newbies for whom this is brand new stuff and what is obvious to the experienced machinist may be mystifying to the beginner. Thanks!

[@TomsTechniques]

That's who these videos are made for. It's good to hear that they are helping. Thanks for watching. Tom

[@robcullen9984]

Thanks Tom Was trying to cut a 3mm deep oring groove in a manifold today, got it half done and broke end mill, was running way too slow 1300rpm, after seeing this vid i know i was miles off the speed, will have another crack tomorrow Thanks Rob

[@scottburrous2375]

Tom, I got my intro to RPN in 1970 when I started with computers. Most of the guys in the class just rolled their eyes and shook their head. I loved it, made so much sense. It was sometime in the mid 70's when the $100 simple/stupid algebraic calculators came out but no RPN. Got my HP 41CV in 81 along with a few modules and memory. I used the navigation module to replace the multiple books required for celestial navigation. I was going to answer the question.but you beat me to it😊.

[@TomsTechniques]

+Scott Burrous I would be absolutely lost without a RPN calculator. You nailed it saying that it makes so much sense. I' all about the logical approach to solving a problem. Sorry if I stepped on your response. :) Tom

[@gabrielbonannoo]

thank you tom Thats the simplest explanation of cutting speed. Real basic topic I know but the basic things are the most important.

[@wiav8r]

Cool tutorial Tom. Reminds me of the way my Dad used to explain things to me as a kid. My Dad was old school machinist. I never took to the trade but love watching all the videos. Puts a smile on! :)

[@TomsTechniques]

Thanks Allen, I'm glad you enjoy them. Tom

[@DFSshop]

Extremely well explained. Any simpler than this just isn't possible Well done, Thank you

[@TomsTechniques]

Thanks!

[@plainwornout3964]

This is right up there with the most useful info us new hobby machinist could possibly get. THANK YOU!

[@TomsTechniques]

Thanks for watching

[@rickhelsel5355]

Tom. Thank you for taking your time to make these vids. I'm just a rookie at this , but am learning fast.

[@TomsTechniques]

Thanks for watching.

[@Canon060009]

I appriciate your vids, they're so simple, informative and very easy to be understandable. Thank you, Tom!

[@theartman410]

Thank You. Just used my first end mill. Like how you made it easy to understand and follow along. Sure going to save you in my files of help.

[@sincarisma]

Thank you very much, the results of my milling have greatly improve after watching your video.

[@TomsTechniques]

+Marco Sandoval That's good to hear. Most people tend to run an end mill too slow because they are afraid to burn it up, but that often results in breakage. Proper rpm is critical. Thanks for watching. Tom

[@LongIslandEddie]

Tom, I cannot thank you enough for the compendium of knowledge that flows from this instructional video! Like you, I am dedicated to the art (or science) of manual machining, and usually rely upon intuition when setting speeds and feeds, but you clearly give me a more full understanding of the ratios that work best. Nice to know you Tom, I'm subscribed! Thanks again!!!

[@TomsTechniques]

Thanks Eddie.

[@mattgwinner4783]

Tom you are my new best friend, I have looked at the charts and tried to understand the written explanations (few and far between) but you have nailed it on the head. I was completely sold when the impact ran to loosen and tighten the tool holder a man after my own " get it done" attitude, I hate tightening and breaking loose the collets' and you have given me the proof that that is a good idea as well. Thank you so much and I look forward to your other straight forward videos. I realize this is basic to you but for those of us starting it is invaluable. God bless the internet, you-tube, your new website, and you as well.

[@TomsTechniques]

Getting the basics down will pay off in good looking and precise parts later on. Thanks for watching. Tom

[@trp3141592]

Thank you for this clear explanation. I have printed out a chart of the cutting speeds and the rpm formula. My antique Vernon Mill has no electronics, so my first task is to measure the rpm of the spindle for every belt setting. With that info I can set my rpm to fit my bit and material. Thank you again!

[@TomsTechniques]

It's good to hear that the material is getting used. Thanks for watching! Tom

[@jackotoole2265]

For metric multiply the cutting speed by 25.4 , surface mm per minute. eg mild steel = 2540 , and use the same formula. 5/8" = 15.875mm 4* 2540/ 15.875 = 640 rpm. Some rounded off number for the other metals. Tool Steel 1800 Cast Iron 1500 Aluminium 6400 Brass 7500

[@StepSherpa]

+Jack O'Toole metric cutting speed is measured in m/min. The formula for figuring out the rpm is (cutting speed x 1000)/(pi x tool/workpiece diameter)

[@jackotoole2265]

+Espen Andre thanks, I agree, the above is just a means of using a cutting speed quoted in feet per min with metric sized tools. Tom has a simpler answer which I overlooked before. cutting speed fpm x 100/ tool size mm

[@TomsTechniques]

+Jack O'Toole I meant to post that in the video but completely forgot. Guess there's no time like the present. :) Tom

[@thomaswilley1956]

Toms Techniques a

[@thomaswilley1956]

Toms Techniques a

[@Andrew-qo6br]

Great tutorial. Very good, clear explanation/examples.

[@arkansas1313]

Tom, very helpful. SFPM is easy to understand by watching your 'show and tell' method! EXCELLENT! Thanks....13

[@TomsTechniques]

Glad to be of assistance.

[@WilliamCooperoverdrive]

I was waiting to see the cutting saw in action! That was a big chunk of steel!

[@proteuswave]

Thanks for the video! Very informative for someone with two new machines.

[@pbc1951]

Great Video !!!! This is by far one of the most informative to the point videos I have seen. I appreciate that you kept it simple and showed how it's done. I am new to metal turning and this is a fantastic jump on point!! Thank You! (Copied from Keith B) Thanks Keith B..... Paul

[@747maran]

Thanks Tom, one of best most informative video for a newbie like me, thanks for the time you put in for these videos

[@TomsTechniques]

Thanks for watching.

[@dannykrumpton4467]

Thanks Tom, cut a new bit today very slight rake and used air for coolant , back gear on the BP little faster on the travel speed , all went well .

[@TomsTechniques]

Good job.

[@TomsTechniques]

Chuck, I'm not a big fan of carbide in the hobby machine shop, so all of my cutting tool videos will be HSS oriented. To answer your question, carbide is generally run around four times the cutting speed of HSS and at much higher feed rates. Well beyond the capability of most hobby type machinery. I will be covering feed rates in a future video. Tom

[@clarkstevens2711]

OMG thank you for some good information for a change it was very educational I've been looking on KZbin for days trying to come up with what you just told me

[@TomsTechniques]

Thanks for watching!

[@johngilley3518]

Very informative. I can also hear the air ratchet on the draw rod, I always wanted to try that.

[@TomsTechniques]

I works very well, except the cheap Harbor Fright impact wrench leaks air like crazy. I bought s nice Ingersoll Rand impact wrench for it, but haven't had time to adapt it. Tom

[@transistor754]

Thank you! As a hobby fitter/turner, it gives me a starting point. The rest is up to me to feel the feed rate.

[@Baza1964]

Getting my mill working later this week. Thanks for the info.

[@havebenthere]

I seem to be under speeding most times, then I gradually speed up in following cuts. I never break an endmill but I take to long. Sometimes I don't have a clue what type steel I'm cutting, Hence underspeeding. I've always watched the chips to get a feel for the cut. Thanks for the videos, I'm picking up alot!

[@TomsTechniques]

Too slow an rpm is quite common, but it does waste time and increase tool breakage. There is nothing wrong with going by the color of the chips and feel of the cut, the formula just gets you in the ballpark. Thanks for watching! Tom

[@2007markb]

Thanks for the quick reply. I just subscribed to you last night. I already used the tip on squaring the vise in one pass. Works like a charm!

[@LeoA-t4z]

I just wanna say 1000 thank you for your simple information 🙏

[@diogenese2]

I'm so glad you taught me what speed to run my tool.

[@Runemup48]

I'm one year in on a Clausing. Love coming across videos like this.

[@TomsTechniques]

What model Clausing?

[@Runemup48]

@@TomsTechniques I dont know the model but they bought it new in 2016. I'll let you know when I go in tomorrow. I also operated their Vectrax and Bridgeport. I'm new to this field. Milling is different from running a turret.

[@Runemup48]

@@TomsTechniques It is a standard knee though.

[@Runemup48]

@@TomsTechniques Clausing 2VS08

[@RenewTheRWandBlue]

I can't thank you enough Tom for this video! I've been doing some milling for awhile now, just fumbling along. It's been on my mind to learn the proper feeds and speeds to make jobs go faster, and I now know that I have been running my mill WAY to slow. I had no idea you could remove metal that fast on a vertical mill. Thanks again!

[@TomsTechniques]

Be sure to download a copy of my cutting speed and rpm chart from the website (tomstechniques.com). That will save you even more time. Thanks for watching. Tom

[@wayneklinkenberg2719]

Awesome video there. I've been going to college training in turning and fitting, but a lot of information has been left out in thin air, making it a little risky. Thanks for the tutorial. Its gonna make life a little safer in the workshop!

[@TomsTechniques]

Thanks Wayne

[@GoldenSim27]

very usefull informative video , getting back into machining after years , needed a bit of study , well explained

[@TomsTechniques]

RPM and feed rate determine chip load so yes, it does have to be taken into account. But that's another video. :) It's good to hear that you are getting some benefit from my videos. Thanks, Tom

[@coyzee1]

Hello Tom, I'm glad I found your site it's excellent viewing. Thanks for the effort you put into making relevant, easy to understand info for us beginners.

[@ronhubbard4663]

Tom, as I've told you before your videos are very informative. Keep 'em coming. Ron

[@sixtyfiveford]

Exactly what I needed to know.

[@kazza3281]

There is a great book, I don't know whether you can get it in the US but, it is called the Engineers little black book. It has all the formulas and charts you could ever need. Mind you I still have my father in-laws old book from when he was an apprentice fitter and turner.

[@dylansmith3660]

Wow... Tom, I wish they would show videos like these in my inside machinist trade theory classes instead of boring old videocassettes that are noisy, worn out, full of horrible audio, and not as engaging. I learned more in this video about cutting speed and the tools you showed more so than seeing it in a book or watching drab by-the-numbers instructional videos. Not as interesting. Thank you for this. I'm a green, fresh, first year apprentice inside machinist and I need all the 'real world' help i can get. It's a new career and a new path to learning. Would love to see more videos like this!

[@TomsTechniques]

Thanks. It's always good to hear that videos are appreciated. I've taken a bit of a hiatus, to get used to this retirement thing, but there will be more to come, once I get my act together.

[@bangtwister]

Thanks for that. Never understood it until I watched your video!

[@stephenwright7065]

Thank you for this! I'm going on 3 years of experience in a tool and die shop (no schooling). We mainly work with tool steel and cold roll steel.

[@woodywoods5373]

Thank you I learned quite a bit it's exactly what I wanted to know.

[@diegorocha6733]

What a good video! Showed me exactly what I needed to know. Kept it simple too. Very nice.

[@lintelle2382]

I recognize that confounded RPN calculator of yours! ;-) thanks for this video. very helpful.

[@TomsTechniques]

Thanks. I couldn't live without it.

[@lintelle2382]

@@TomsTechniques used a TI-59 the last year at DeVry 1982. Never could change mindsets to the HP way. PC versus Mac maybe??

[@mikebetts2046]

Outstanding presentation. Thanks for teaching me a few things.

[@TomsTechniques]

Thanks for watching

[@MrThijsthebest]

Mike better use this: rpm x number of tooth's x feedrate per tooth (0.05. = finishing) (0.1 = for removing material) or use that if u want to bake steel and ur mill

[@TheChrisey]

I noticed that RPM can really mess things up if you get it outside the ballpark. I was cutting a sort of oval hole for an exhaust flange in mild steel with a 10mm thickness (just short of 1/2"). I used a 14mm endmill, and managed to completely burn it up to the point where the endmill became miscolored running at about 1400RPM. Turning it down to about 780RPM made it run so much better with a new end mill, and it didn't burn it up.

[@TomsTechniques]

Too slow and they break, too fast and they burn up. RPM definitely matters.

[@TheChrisey]

@@TomsTechniques What I don't understand is, how can they survive in CNC machines running several thousand RPM?

[@kennethd4958]

@@TheChriseyThe only thing I’ve figured out is that it’s because of how precise CNC milling can be over manual mills. But CNC’s can still burn up tools if not ran properly.

[@profesonalantagonist]

Total noob here. Just bought a 40 something year old Jet 16 drill-mill from a friend, and trying to learn all I can before I start my first surfacing/milling project. I understand the surface feet per minute, and the bit diameter, but why 4? Why not 3, or 5, or some other number. Since surface speed must be multiplied by 4, 4 must have a significance? Otherwise if it is always 4, then by default surface feet per minute for mild steel would always be 400. Then could be simplified by simply 400 / 0.625 = 640 ? I must say though your tutorial has explained bit speed better that any other tutorial I’ve seen! I certainly have more confidence to start my project than before I watched this !

[@TomsTechniques]

I think you are misunderstanding the formula. The 4 is just a constant in an easy to remember formula to provide an approximate rpm for various cutting speeds and diameters. In the case of mild steel, the cutting speed is 100 sfpm (not 400). With your ,625 diameter part, that works out to 400/.625=640rpm. For aluminum, with a cutting speed of 500, the rpm works out to 2000/.625= 3200rpm.

[@profesonalantagonist]

@@TomsTechniques , Thank you for your quick reply. Your formula is very simple and easy to follow. Your formula helps me tremendously! But primarily the question is about the constant # 4. Is the constant always 4? Is it possible to ever be another number? Is there a reason the constant is 4? Or is it one of those things that just is?

[@rhysevans6659]

Very useful for my report on the milling process, thanks!

[@TomsTechniques]

Thanks for watching

[@jondoes7836]

I never knew how to calculate speeds & feeds when I ran manual machine tools. I’d look at the spinning cutter or workpiece and figure that’s a good RPM to start with. I’d adjust my speeds & feeds from there based on the surface finish, rigidity of the machine and workpiece setup and horsepower of the machine. I did have to calculate speeds & feeds when I learned how to program & run CNC machines. The actual speeds & feeds to cut are put into the machine program.

[@TomsTechniques]

Thank You. I'm hard at work building a website to help organize the existing videos and new ones to come, so stay tuned. Tom

[@johneubanks5951]

Wonderful video and very understandable. Thank you . subscribed 💪🤘🇺🇸

[@shredder60]

This is an outstanding video Tom thanks for this.

[@TomsTechniques]

Glad you liked it. I just realized that I never posted cutting speed chart on my website. I've been working on it and it will be available in the reference section shortly. Tom

[@shredder60]

Toms Techniques This type of info is what I and probably alot of other noobs are looking for.all the calculations and what there for.

[@tonypitsacota2513]

If your measuring your stock diameter in mm, use equation "rpm=97*SFM/SD" instead of 4.

[@deemstyle]

It was a simple formula, but I didn't know it. Thanks for the great video! I'll go search- maybe you've covered it, but perhaps a followup video on carbide? That would be great!

[@TomsTechniques]

Thanks. Carbide can be run at roughly 4X the cutting speed as high speed steel. Tom

[@deemstyle]

That was quick! Thanks for the response!

[@bomataralshamsi]

It’s a very good new knowledge that I got today thank you bro 👍🏻

[@jonarbuckle1560]

That simplified formula is super handy. It really gets you in the ballpark in a hurry!

[@TomsTechniques]

Thanks for watching!

[@TomsTechniques]

It's actually a DoAll mill. When I bought it in the 80's, the Bridgeport/Textron mills weren't the quality they once were.This one has served me well over the years. Tom

[@userwl2850]

looks like a bridgeport miller with the R8 collets. built in england. i have 3 of these. great tools.

[@johnbarnwell400]

Thank you sir this was very helpful to me !

[@justlearn1992]

very good video Tom!!! Helped me out big time. Glad I found your videos

[@TomsTechniques]

Thanks.

[@mdnabihussain625]

Thanks you sir for uploading this video and put your time for student ..nice

[@TomsTechniques]

Thanks!

[@outsidescrewball]

Hi Tom...is that example for HSS tooling? Does it change for carbide tooling ? Pls explain SFPM to feed rate and depth of cut...thanks, Chuck

[@medinacentral]

Great video! Very informative. Thanks for uploading!

[@noecortez8677]

thank you tom for such a helpful video great job and easy right to the point

[@TomsTechniques]

Noe Cortez Thanks for watching!

[@markdavidson7510]

agree with everyone here. Thanks for putting this together and understandable for a first timer

[@TomsTechniques]

Thanks for watching!

[@gymkhanadog]

Awesome information and very well presented. Thank you!

[@EnglbinkHooperdunk]

Excellent information, 2 questions though. 1 What about Stainless? 2 Is the 4x the SFM in the formula referring to the number of flutes on the cutter?

[@TomJonesGA]

Great info: I got the tool speed, but how did you figure the material speed/depth of cut? When to use oil/not to.

[@robertdubard7959]

Rule of thumb for depth is 1/2 tool diameter (for full width/slot milling) .

[@robertdubard7959]

Lubricate & cool whenever possible.

[@robertdubard7959]

Material feed is a bit trickier. Best starting point would be #flutes x rpm x chip thickness would give table speed (in inches per minute) Cutting mild steel with HSS endmill avout 1/4 diameter, you can start with 0.001 for chip thickness--it can be higher for bigger diameter end mills, harder cutters, and softer materials. See, the fundamental thing that drives those calculations is the desired chip thickness (per tooth), which is different for the cutter material and the material being cut. And more teeth per revolution (more flutes, basically) interacts with the spindle speed. (Someone will disagree with me in 3, 2, 1...)

[@ujjwalkumar4912]

awesome and mindblowing practicle sir,

[@Hawk74]

Great video and simple to understand, thank you.

[@iiinsaiii]

Thats cool Tom and if you can do some 5c spin index video's, that will be great because there not one person on KZbin showing anything on it and how it works and what you can do with it.

[@sustrasbk]

Great video! One thing I can't seem to find information on is what is the recommended depth of cut for slot drills? Perhaps you would be able to advise. Cheers

[@TomsTechniques]

You can use any depth you like by adjusting the feed rate, but generally the most efficient depth for end milling seems to be about 1/4 or so, the diameter of the end mill.

[@timshel011]

Thanks for the great video. My question is,why or where does the constant of 4 come from in the formula ? Just would like to know.

[@TomsTechniques]

It comes from rounding pi to three and converting from inches per minute to feet per minute (12'' to the foot). If you scroll down through the comments, Rex Walters does an excellent job of explaining it in detail. Thanks for watching. Tom

[@kelvinyonger8885]

a more precise formula is 3.816 * SFPM / diameter = RPM. The 3.816 (or 4) combines pi with the inch to foot conversion

[@Quingal]

Very simply put and useful....

[@TomsTechniques]

Thanks. When I get the chance, I'll write up a reference sheet for this video and add it to my website. There have been quite a few requests for one. Tom

[@kensendelofski3761]

very informative. Just getting started in milling.

[@2007markb]

I finally understand how to get to that....thanks! But my question is, how about a fly cutter? Ive watched videos with guys running fly cutters and they seem to be running them at an extremely high rpm. What would be the formula for those cutters?

[@terrycannon570]

Outstanding as usual. Thanks Tom

[@TomsTechniques]

Thanks Terry

[@robertroy6094]

Excellent video. What about feed rates now?

[@TomsTechniques]

Feed rates can be calculated on a machine where it can be accurately controlled, but most mills like this are either manual, or have variable rate power feeds. On those, you pretty much have to rely on the feedback you get from the machine and from watching the chips. In other words, from experience, a difficult concept to explain or teach in a video. Once I start making videos again, I'll try to figure out a way to do it. Tom

[@sir7hC]

Hello, in this video you said you can find the cutting speeds in any machiner’s handbook or references; what handbooks and reference would you recommend?

[@TomsTechniques]

There is a pretty complete cutting speed chart in the reference section of my website. For general machining reference, it's hard to beat the Machinery's Handbook. New ones are pricey, but they come out with new editions every few years, so there are lots of older used copies available. Another good one is the Machinist's ready Reference. It is more basic than the Machinery's Handbook, but that can be a good thing for the new machinist.

[@MyShopNotes]

Hi Tom, your a resource I can't seem to get by without. Would it be possible for you to put more reference material up on your site? This is the 3rd time I had to watch this video to remember the 4xsfpm/dia. Would be easier if I could just link to a page on your site. Ya, I'm getting older and cannot remember things that easily anymore, in particular the newer stuff I am learing.

[@TomsTechniques]

Hi Steve, A cutting speed reference is on my to do list, but I haven't figured out how to best present it yet. Maybe you'll just have to write it down for now until I can get something made up and posted. I actually have a reminder on my gmail that pops up every time I open it, so I promise I won't forget. Thanks for watching and it's good to hear that you can't get by without my site. :) Tom

[@RVJimD]

Thanks. Just thinking out loud here. Where does the 4 come from? And when or how is the conversion from feet to inches happen due to the sfpm desired speed and tools measured in inches? Thanks for the videos! Jim