Use of the Fly Cutter on the Milling Machine
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- เผยแพร่เมื่อ 16 มี.ค. 2014
- The fly cutter is a very useful accessory for machining large surfaces in the milling machine. This video covers how to use the fly cutter and how to properly grind a cutting tool for it.
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Nice job Tom. We are always encouraged when we see knowledge passed on to future tool makers.
Thanks.
Someone needs to pass the baton. The state of manufacturing in this country in sad shape. If we want to maintain our current standard of living, we need to get back to making things instead of paying someone else to do it.
So...got any free samples? ;)
Tom
Toms Techniques there are lots of home shop machinist, thank goodness.
@@TomsTechniques Well said sir. America used to set the gold standard for quality manufacturing, especially in machine and tool manufacturing. Now, we don't make anything.
I really like your method of teaching and demonstrating the techniques of machining. The running comment is excellent and provides valuable information while watching what would otherwise be just a repetitive cutting operation. I don't dare jump forward in the video (skipping the cutting operation) because there is valuable commentary during the run. You do a great job sharing your skills and hard won experience. Thanks Tom. Congratulations on the large number of subscribers, well deserved in my book. It was also nice to see you "in person" at the beginning of the video, and to share in you delight at having received the spanner gift.
Thanks Jim.
The running commentary is an integral part of teaching and helps hold the attention of the student (or viewer). It's something that is picked up with experience and even though I haven't formally taught for many years, still comes fairly naturally. It's good to hear that it comes through in the videos.
Receiving the spanner was a nice surprise. The fellow who made it actually lives close to where I work, so I'll have to set up a visit.
Thanks for watching.
Tom
Glad that you enjoy teaching because there are many of us that are willing to learn. Thank you for making these videos.
That grind your put out really made my cheap import fly cutter sing. Wonderful finish. Thank you.
It's all about the angles.
Thanks for watching.
I just got done watching your safety first videos because I think that it is important to always be aware of your surrounding and you could bring up a point that others teaching safety had missed. I consider myself as an armature machinist so its nice to see how some operations are done. Subscribed .
Thanks Brian.
Flycutter a great tool for the hobbyist. Single lip cutter .. doesn't have to be symmetrical in any way. Nice project and a tool you'll reach for over and over. Great grind content
I ground the bit per your instructions and used it on some 1018 I had laying around. Absolutely beautiful finish. Thank you for the info!
+Clevinger Customs
If you got a beautiful finish on 1018, you did a very good job grinding the tool.
Thanks for watching.
Tom
Its great to see someone willing to take the time and explain a dying art. I have worked in the manufacturing industry and it seems like no one wants to give you the time to show and explain proper machining methods thanks
Thanks Brian.
Machining has become very specialized and good general machinists are not nearly as common as they used to be. Hopefully these videos will help provide some general knowledge of machining.
Tom
@@TomsTechniques it might be a dying art, but I love it and am trying to become the best I can at it
I've never heard of anyone refer to machining as a dying art. There isn't as much manual machining going on as there used to be, but CNC operators and millwrights are in very high demand. Most of the manual machining practices still apply.
@@TomsTechniques I dont refer to it as that either, but there still is not enough people in the business for the job outlook. Companies around where I live are so hungry I was offered 6+jobs last week alone. Its a good business to be but there needs to be more people interested in it. I am actually about to graduate this month from my trade school. Manual machining is my favorite, but I do CNC as well, CAD/CAM too. Im happy to have found machining
@@TomsTechniques In a 2 year late reply, I can't speak for the commentor, but I am an engineer in Lithography industry. POSSIBLY what he means, is how everything he become "automated" and operators don't have to be very skilled. Of course the automated machinery, has to cover those skills. So I would argue that finding "good lithographers" which is a VERY high knowledge, decades of learning.... the mastery of the skill has "become a dying art." We have new ways of doing it, and blah blah.... when someone says, "automate me a machine that feeds paper board and batches it. Can you make me a Pile feeder?" I might say... "Yes I can. But tell you what, let me make you a continuous feed top load friction feeder, that a COMPLETE MORON can operate. Doesn't matter who they send you from the temp agency, or who quits, or is availble to run it... AND I can make it so you have equal or better production. So I've eliminated them ahving to set the table rise speed, set the blowers correctly, the vacuum wheel adjustment... and to be honest, all of that is simple. BUT everything I design for an IDIOT to be able to run it. 10 years ago casual labor was almost imposible to use in lithography. The SIMPLEST of work, required skill. You are showing and demonstrating skills, and practices, techniques, etc. Verses somebody but an automated machine, you program in numbers off a piece of paper, and monkey can run it. Probably NOT quite that simpel in machine, and its still not quite that simpel in printing, but its getting that way quickly. I'm here because i have to design, build and automate so fast I sometimes don't have time for my parts to be made. I don't want to be a machinist.... but I need to learn a little bit for the mil I just bought for emergency design parts. THANKS TOM!
Thanks Tom. Wonderful to watch.I learned a lot watching this and I appreciate the effort you went to.
Thanks for watching.
Thanks Tom, for taking the time to share your years of experience with us. Truly appreciated I always learn something new from your informative videos. Thanks again. Mike
Thanks Mike.
Thanks! I just got back from the workshop where I successfully ground a tool following your instructions using the aluminium angles and got a fantastic finish on a delrin thrust bearing block that needed a few mm taking off it. I'd been avoiding doing this for a while due to my ignorance.
Success stories are always good to hear.
Thanks for sharing.
Tom
Over the past year I built my own CNC mill, and it's because of videos like these. Thank you for taking the time to make some chips for the sake of me getting smarter!
I would like to see that. Do you have any pics? Send me a message through my website, if you wouldn't mind.
Tom
Obviously so many years of experience in this one video. Appreciate the great information.
Thrilled to find your videos Tom! Thanks for sharing your knowledge with us.
SHAWN DOYLE
Thanks for watching them Shawn.
What I like most with fly cutters , is that you can cut much larger diameters than with most face mills in one pass. The finish is always better, at least visually. Thanks for the video.
i made my 1st flycutter in the 9th grade, '67.... the one you show is bass-ackwards, you want the beefy part to back-up the cutter and have the securing screws in the thinner (front) portion. and while it's true the cutter doesn't care about rotation, the COLLET does.... cut counter-clockwise and you'll un-screw it. and the most important adage of all is : you can eat with false teeth, you can walk with a peg-leg, but you CANNOT see with a glass eye. i thank you for keeping a fading craft alive, after 50 years i have little hope we will regain our manufacturing might. please continue to teach the next generation, enthusiasm and mistakes = journeyman. . . . . God bless - retired ron
You must be referring to illustration in the cutter diagram, which is just to show how the tool is used and not intended to build a fly cutter. If you look at the actual fly cutter I'm using, the set screws are indeed pressing against the top of the tool with the tool resting on the beefy part of the fly cutter. Not sure I understand your comment about the collet though. Collects are keyed and can't un-screw.
Pretty sure I made my first flycutter at about that same time. :)
Another informative video, Tom. Thanks.
I am looking forward to your series on making a knurling tool. That should have lots of components for various skills as well as be a useful project.
Thanks again for your videos. I look forward to them.
Joe
Thanks for watching.
when I was first learning how to hand grind tools I turned lots of "high speed steel" pieces into HIGH SPEED STEEL flying across the shop usually with a small chunk of my skin that it tried to eat.. I guess it's safe to say I learned quite a few valuable lessons painfully quick! Excellent videos Bud Thank You for making them!
Flying steel is rarely a good thing. Good to hear you came though relatively unscathed.
Thanks for watching.
Congrats on 10k subscribers Tom - you have a fine collection of videos now, which are educating people around the globe.
Tim
Thanks!
Very helpful video Tom, appreciate your efforts!
thanks Tom! you keep making them I'll keep watching them,,, I always pick something up !
thanks
Thanks for watching Ron.
Hi Tom Thanks for your generosity in making these excellent videos. As a learning hobby machinist, shared knowledge form professionals' such as yourself is a Godsend.
Keep up the good work, Ps I loved the carriage stop series.
Thanks again
Terry
Thanks Terry!
+Toms Techniques Thank you very much for this video and the accompanying grinding guide. I ground my first fly cutter and used it on some aluminum tonight, and it worked great. I wouldn't say it was a mirror finish, but it still turned out great!
Thanks again!
+Paul Frieden
That's good to hear Paul. Try stoning the cutting edge for an even better finish, especially on aluminum.
Tom
Hi Tom- Outstanding video! Framing and lighting were spot on! Congrats on 10K!
Good to hear because it's always a challenge to get right.
Thanks for watching.
Tom
Old School! I love it. Lost art, you know the "gifted" guy's when you work with them. I learned right here. 70 year old toolmaker screaming at me. Irreplaceable knowledge. Keep at it! The younger's will not understand. Yes, i'm that old.
Damn! As I watch, I have forgotten much of what he is describing, yet I know what he's saying. Well done!
Edit: Larry, 72, would say to me "I have forgotten more than you will ever know". He was right.
Old school huh? I've definitely been called worse. :)
My "Larry" was Ernie "The Kraut" Kraudelt. I used to love to watch him work.
Tom
Tom, great video! When I mill I always get into the habit of putting my quill as high as I can. It requires that the mill table be higher but it makes for a more rigid setup!
I do that as well, if necessary, but light milling doesn't require as rigid a setup and it saves a lot of cranking time to just leave the table alone if you don't need one. Rules like that are never absolute.
Yes it should always be fully engaged, especially for flycutting. I was taught 'the quill for drilling, not milling'.
Tom.
Thanks for the info.
Looking forward to more of your educating videos.
Chip on!
Thanks for watching!
Thanks Tom. This video is very informative. Thanks for sharing!
Thanks Herb.
thanks Tom , your vids helped me a lot .
Hi Tom,
Congrats on your 10,000+ subscribers!
Thank you for doing this video, you did a very good job demonstrating the grind and use if the fly cutter!
Thanks again,
Ray
Thanks Ray!
Super segment Tom. I watched this one with great interest! I think they call it a fly cutter because the chips fly over all over the place... Thanks! Fred
Another good explanation!
Thanks Tom very educational to me. Also good to see you expand the cameras view.
Thanks Cliff.
Congratulations on 10,000 subscribers, Tom! That's quite an accomplishment. You deserve it. You do a great job on your videos.
Thanks for watching Thad.
That's a craftsman grinder! Wow from way back when craftsman was a quality company
I've had that grinder for more than 40 years and it's still going strong. I doubt one made today under the Craftsman name would last that long.
Hi Tom. Thanks for that. I've been looking for guidance on how to grind a fly cutter bit without much luck - until now! I am very much a beginner and find some of these basic concepts difficult to grasp, so I appreciate you having taken time over it. I find the nomenclature used is sometimes difficult, I think sometimes people call the same 'slope' on the tool by different names - guess I'm easily confused. Bob.
Thanks Bob.
Don't forget to visit my website and download the diagram showing all of the tool angles.
Tom
Thanks for great tutorials. Useful to me as a beginner!
Thanks for watching, David.
Am I the only one that appreciates the HP calculator? I had one that looked just like that (HP15C) which I used in college over 35 years ago. I don't know what happened to it, but I loved it! I bought some HP 32S II calculators for work back in the mid 90s and they are still going strong today, even with heavy daily use since they were bought. The new ones are definitely not made like the old ones!
I have a couple 32S models as well. They are much easier to find than 11 and 15c's. My mind works in RPN, so they are the only calculators I use.
@@TomsTechniques I have never done any machining, only design work. I would like to get into machining and I am enjoying learning from your videos. Thanks!
Thanks for responding I was concerned about you see you in the fall.
Another excellent video Tom thanks a bunch
Glad you enjoyed it.
Thankyou for your time and knowledge
Congrats on 10k. Excellent video as always...
Thanks.
Wish everyone used the metric system, I have to go google every time you talk sizes, another great video, thanks for sharing
lol, I wish everyone used the inch system.
Thanks for watching.
Tom
Thanks for the knowledge, it is greatly appreciated my mill is on its way to me as im typing this , it is just a little toolco 30 mill but it is my top of the line Bridgeport, again Thanks.
Good video. Thanks for posting!
Thanks!
Your videos' are excellent, Tom, and this one is as good as it ever was.
Thanks for watching.
i am currently taking a precision machining class at a trade school and i absolutley just love doing this everyday
It's always a plus to enjoy the type of work that you do. Not everyone does.
Tom
Thanks Tom have done Fly Cutting in the past, but hit and miss on the finish. After watching the video ground my tool your pattern and hey perfect result Thanks once again.
Great Bob. I always enjoy hearing a success story.
Thanks for watching.
Tom
Tom, Great clips for a novice like me. Keep up the great work
Thanks.
I am now subscribed after watching this presentation. Many thanks.
Great! Welcome aboard.
Tom
This tool is great for low power machines. U can use face mill as fly cutter. Just leave one tip new and grind edge from opposite one ( just for balance).
I use this technique on commercial high power mills to get mirror finish effect :)
OUTSTANDING--FOR THE FIRST TIME IN YEARS SOMEONE ELSE KNOWS THE SECRET
HI Tom
Got you covered took the picture off the post office wall
keep up the great videos
Thanks Don. :)
I have not seen anything new for a couple of months. I was hoping you had not given up of us newbes. Looking forward to seeing more in the future.
Bill Clifford
Haven't given up Bill. I still work full time so when summer rolls around all my spare time is spent in the great outdoors. Not much is spent in the shop.
Tom
good stuff tom , cheers
Thanks for sharing this stuff!
It's always interesting! 🙂
Hi Tom !
First time I ever see your face - nice to see you have more than the two hands we so often see in your really fine videos ;-)) - thx for showing and using the time !
I just made oneof these fly cutters myself - so it's very nice to have this video !
Keld,
My face (handsome as it is) isn't going to show you how to grind a tool bit or cut a thread. Close in shots are a necessity for demonstrations like that.
Glad you liked the video.
Tom
4 times the cutting speed divided by the diameter - popped that right into permanent memory there ;) Then he goes and takes out the HP11C calculator from what I can see! You can only appreciate that when you've used a true PRN calculator. I have the same one and it's got to be the best calculator I've ever owned. Was given to me by someone I worked with years ago. His dad passed and he was a math professor too ;) Good deal!
Yup, it's hard to beat that Reverse Polish Notation. I bought the HP11c in the video back in the 80's and have picked up a couple spares on eBay, just in case. Algebraic calculators are way to slow to use.
Excellent video. Thanks!
Thanks for watching Mitchell.
Tom you are a great insructtor I look forward to your videos in the fall. thankyou see you soon.. Bill
+Bill Clifford
Thanks Bill,
I had planned on making one today, but it didn't work out. Hopefully I'll be able to do one in the next week or so.
Tom
I like that you emphasize safety in your videos, i.e. sleeves up, glasses on, Very well made video, And congrats on the 10,000
I've seen too many bad things happen in my career NOT to emphasize safety.
Thanks for watching.
Tom
Great video! Good narration. U explain thngs well
Thanks, glad you enjoyed it.
Thank you, Tom!
10,000 subscribers is a real milestone.
Congrats, and thanks for the great videos!
Thanks Andre.
Really helpful! Thanks so much!
Thanks for watching, Paul.
Great, informative video. Thanks! :D
Thanks Rob.
Nice video. Wish me luck I'm going out to the shop to sharpen my first fly cutter tool!
No luck required. Just a basic understanding of cutting tool geometry and lots of practice.
Have fun.
Tom
I love the videos, and the wealth of information you provide. If I could get my vote in, how about doing a video on how to set up and use a steady rest and follower rest?
Barry,
I have had a few requests for that and it is on my list of topics.
Thanks for watching.
Tom
Congratulations on the 10K+ subscriptions, and thank you for the videos.
I would appreciate it if you would comment a bit further on using a right hand tool in the fly cutter. I'm just starting out, and the first time I used my fly cutter, I only had right hand tools. I ran the cutter counterclockwise, and it did cut, but I realized that the cutting edge was not on a radial line from the center of the cutter. It was on an extended segment line, giving the tool negative rake.
Thanks Jack.
I think I created some confusion by using the RH tool on my reference sheet. To use a RH tool bit, the fly cutter would need to be made for a RH tool. Otherwise, like you say, the top of the tool bit would not be on axis. I'll go ahead and change the reference sheet to a represent a LH tool.
Thanks for pointing that out.
Tom
love this info ty so much
Thanks for your time to make this video.
I sincerely would like you to show or at least explain what you "shouldn't" do, I and others watching videos have thoughts of how we might do or change something thus getting into trouble.
Shouldn't do relating to what? I do a lot of that sort of thing in my project tutorials. You may want to check them out whether you build the project of not.
Tom
just started watching your videos. now your up to 70,000 subscribers. I'm thinking about getting one of these milling machines.
The DoAll is a nice mill, but they stopped making them years ago. The good thing is they hold up well, so there are still a fair number around on the used market, along with many other Bridgeport clones.
Thanks for the sub.
Another great video, thanks very much.
Thank you.
Good stuff Tom.
Thanks for this :)
Thanks for basic knowledge!
Thanks for watching!
Hey Tom
Congrats on the 10k+....great video production as always
Enjoyed the lesson, just love watching those steady experienced hands on the grinder...I know...I know...practice,practice,practice...LOL
Looking forward to more instruction and a shop tour!
Best regards
Chuck
Thanks Chuck.
I hand ground the end of a boring bar this morning to use as a spot facing tool and it indicated flat within .001" over a 5/8" diameter. You are right that it definitely takes practice to develop a steady hand. I'm thinking of trying to hand sharpen the helix on an end mill next. ;)
Tom
I made a double fly cutter. It takes a second to get both bits even with the surface but isn't bad.
Very good informational video. One critique, that quill should not be extended out. The table should be raised improving rigidity for the cut quality and more importantly the life of the quill on the machine.
Thanks. If I'm taking light cuts, the quill stays extended instead of cranking the knee up and down. The time I've saved not doing that in my career would likely have paid for a new mill or two. Obviously, heavy cuts require the rigidity of a raised quill, but for most machining, I rarely touch it.
Great vid, I use my flycuter as a boring head too for some special projects that are too big for my Taig sized machine boring head.
You know you can mount the flycutter in your boring head to get more extension on the tool and still have the adjustment of the boring head. I've done that a lot.
Tom
thanks for your time ,,, the videos are very helpful,,,,,,
Good to hear!
Cheers for this
Dale's a good dude!
Who's Dale?
I like using fly cutters for large hot roll steel angles. It cuts through the hard scale surface. The one cutter minimizes the vibration, so each pass of the cutter allows just enough time for the steel angle to correct its rest position and make a smoother cut. multi flute or face mills with multiple insert cutters makes for a rough finish if the angle starts vibrating. plus cutting thru scale is hard on face mills. the inserts are pricey and isn't easy to sharpen. the fly cutter can be re sharpened many times and doesn't cost much.
Congrats Tom.
Thanks!
This is the first time dated January 25th. I subscribed to continuing watch your videos. I began recently, following the ytube. So I look forward to see 🙂 additional machine stuff.
Thanks Keith. We just moved and all my machines are in storage, but I do plan on making more videos, once the new shop is set-up.
You fully deserve the recognition.
Keep up the videos, much better use of internet band with and up lifting than porn...
I've used this kind of set-up on aluminum taking cuts 200 thousands deep, over 2000 rpm and feeding as fast as I was able to crank the the wheel, these little rascals are deadly efficient eating metal.
With all the demands from viewers you'll be 100 year old and still running.
Thanks again Tom,
Pierre
Wow, it's good to know that my videos are more uplifting than porn. :)
Thanks for watching!
Tom
I wasn't talking about the Viagra effect, let's say on a more spiritual level...
lol
amazingly helpful video
That is good to hear. :)
man does a fly cutter make a big mess though, throws shavings like 10 ft
thanks Tom.
Keep up the good work Tom, you are a pleasure to watch.
Every time I watch you work on you mill it reminds me how flimsy my Sieg SX2 really is.
One thing I do want to make for it though is a fly cutter. I presume the cutting edge is radial to the centre line of the shank?
Thanks Ray.
A fly cutter would make a good project, I'll have to add one to my project tutorial list. Yes, the top of the tool is coplanar with the axis of the fly cutter.
Tom
Thanks dale
Great Video lot of really great info.... Would love to have a copy of your cheat sheet for cutting angles on the cutting tool but I'm not smart enough to figure out how to find it. I know you said you would post it but like I said I'm not smart enough to find it... Thank you again!
Glad you enjoyed the video. All of the charts and tables I used in the video's are available on my website, tomstechniques.com.
Fantastic! :)
Thanks
Thank you
Hello Tom, thanks for the video. Very handy tool. Where can I get the cutting tool geometry
paper again? Thanks
i’m in machining at my school and we are making fly cutters and a t handle tap wrench right now. well when we go back to school
I still have and use the tap wrench I made in school, fifty years ago. :)
Hey Tom, great lesson for sure as they all have been. Thanks for taking the time educate the newbies!
Had a question if you have the time...
Have some custom fly cutters and they came with carbide bits vs HSS. I had heard that you need to "break" the edge on the carbide to make them cut better and last longer.
I'm trying to figure out how to dress them (what stone to use) and how much if any radius?
Have been looking on the net and haven't found a way yet.
Any help would be much appreciated.
Best.
Wiredodger60
I assume you mean brazed carbide bits. The cutting edges on Inserts are already "broken" by nature and not near as sharp as HSS which is why they require rigid machinery with lots of power. Since most home shops don't have that kind of machinery, HSS is a much better option. If the bits you have are brazed tips, leave them sharp. You'll get a much better finish on a light mill.
Tom
Great sir
this guy is awesome... and he sounds just like norm McDonald.....
no1wrench
I've actually heard that before. Guess I'll have to find out who this Norm character is.
Thanks for watching.
Tom
no1wrench Lol, I hadn't noticed that until you mentioned it, yes on both accounts.
Toms Techniques Maybe you should find out by watching "Dirty Work".
That aluminum is a real jerk!
That's a pretty cool setup. Thanks for showing the grinding of the tool.
Do you think a flycutter, with a properly ground tool (more with a downward facing point I'd guess) could be used to cut a large hole in some plate aluminium as well? I don't have a flycutter holder, but it doesn't look like it's such a hard thing to make with a lathe and mill.
Cheers!
/Daniel
Thanks Daniel.
Cutting a hole as you describe is called trepanning. It's normally done with a pilot of some sort to keep the center piece from jamming when the tool cuts through. A boring head would be a better option than a flycutter, but only if the center was restrained.
Tom
Great video Thanks for making it- 10,000
Video on proper use of Boring head would be great --
I just purchased one and not much info out there on using -
Toms Techniques
Tom,
nice video, again!
I wanted to make a comment regarding what you were talking about with projects versus individual instructional videos: while both are great-and important-the projects are kind of like stories.
the original function of stories, anthropologically, is to get us use our imaginations to simulate situations we haven't experienced, so that we can survive if we do experience them. stories grip us really powerfully, and help us remember critical information.
all through the carriage stop project, I was trying to imagine how you'd accomplish one thing or another, and it was really fascinating.
videos like this are really interesting, too, but contain much less suspense.
anyway, just my 2¢
my 2 cents, it is an instructional video. Wasn't aware they needed suspense. You want suspense, read a good fiction novel
Both types of videos have their purpose and the intent is for them to be used together. The instructional videos are intended for the beginning machinist to teach them basic machining operations. Once they are familiar with the basics, the project tutorials demonstrate how to apply them. It's the old "gotta learn to walk before you can run" thing. If you look on the website, you'll see that each project has a number of recommended instructional videos to be viewed and mastered before attempting the project. The idea is to provide interesting material for all levels of expertise.
Tom
Jasin Colegrove did you even read what I wrote?
ThoperSought
I did, and thought I was agreeing with you while reiterating the purpose of the two types of videos. Sorry if it didn't come across that way but I answer dozens of these comments daily and some just come across better than others.
Thanks for taking the time to comment (and for watching the videos).
Tom
Toms Techniques Sorry, Tom; I didn't think you were disagreeing. I meant the comment for the other commenter.
I agree completely with you that both videos have their purpose, and I think it's really clever to match them up the way that you do on your website.
I don't remember precisely what I was responding to in the original comment, but I think you said something about the projects being new, and the basic instructional videos being the original content; I'm not sure now.
thank you for taking the time not only to reply, but also re-reply!
Very nice. I would like to use a flycutter to remove scale on new 3\16 in thick stock but new to milling and can't see how to hold work piece to do any milling on it other than drilling..
You do have a vise? Just clamp the stock in the vise and fly cut the top surface. If the the top is lower than the vise jaws, you will have to set the part on parallels to raise it up. Be sure to take a deep enough first cut that the tool is below the scale or it will quickly dull.
Tom
New sub here...so glad I found this channel...cant way to go through your library of videos. Several time you mentioned the color of the chip. Could you expand on what you look for in a chip with the various machines and methods? Also related would be what color and shape and size tell you. What information do you gain from a chip and how do you use that info to fine tune the process you are using at the time? Hope this question makes sense...I am going to look at and maybe make a deal on my first couple machines tomorrow. hopefully.
Using chip color as a guide really only applies to ferrous metals. Assuming the proper rpm is being used, you should try to keep the chips from turning straw colored with high speed steel tooling, or anything more than blue with carbide. For aluminum, watch for chips sticking to the tool to tell if things are getting too hot. Depth of cut and feed rate are both factors that contribute to the amount of heat generated with a cut.
Tom