Selecting and questions on indexable/insertable endmill?

Thank you for your time, I'll preface this with, I'm a newbie student machinist, and got excellent advice here before on a CAD/CAM system.

We haven't really learned much yet in the way of carbides, inserts, types, etc. Thus, I'm looking for a recommendation on insertable/indexable cutters and lathe tool.

This year, we will primarily be machining aluminum, and next year we will be working on molds, dies, and possibly other tool steels. The ops I'm looking to be able to do with an endmill is profiling, pocketing, and facing, and for a turning tool one that can do left and right hand turning, radius, and possibly, thread with the same tool. In short, both tools that are good all arounders, and fairly economical to replace inserts. I know it will probably be at the cost of of specializing, but that'll be a question for you guys when I have a black hole tool budget for a MS horizontal. ;P

Looking at insertable tooling, it's flooring how many options there are, in insert types, coolant throughs, high feed or larger DOC types, and frankly I have no idea where to start.

First off, Kennametal, Sandvik, Walter, Kyocera, Iscar, Ingersoll or someone else for a long lasting, quality, durable tool? Do coolant through types require a special coolant system or hookup, or does it come standard on CNC's(Told you I was a newbie)? What machines a part faster (MRR's, right?), something with a lower DOC, but faster feeds, or one with deeper DOC at the cost of feed? What size would you recommend? Any simple reading or videos on it you'd recommend on them? Would you suggest solid or insertable types for use on a regular Bridgeport style manual machine?

Sorry for the wide open, tall order question here, I hope you don't mind sharing your experience and recommendations. But in any case, take care, God bless, and thank you very much for your help!

This was posted recently in another thread about insert tooling.
http://www.carbidedepot.com/resources.htm

Thanks for pointing out the site, ezduzit!

It seems like a great place for choosing an insert type, and seeing the shapes and what they're good for was pretty cool.

Looking at the page here:
http://www.carbidedepot.com/formulas-insert-shape.htm
When it says limited machine power, does that mean if you go heavy DOC(say .1) it would tend to break?

Unfortunately, it doesn't seem to cover much about tooling manufacturer's, what toolholder's shape is adequate for certain ops, if faster feed types (low DOC) are faster overall at removing metal and leaving a decent finish.

Also, what diameter insertable endmill would you recommend? I was thinking a .625 or.750 but not sure if it's strong enough.

Thank you very much for your time!

Don't forget Mitsubishi for indexable tooling we swapped out our aluminum specific R245 Svandik inserts for Mitsubishi's and they just about made the Svandik inserts look like garbage. I think what would be more helpful is a budget you want to stick with

Ah! Thank you, Whysosharp. I'm not sure what kind of budget I should be looking for on an indexable, but I'd rather save up for one that'll last, then spend half as much and end up buying more in junk. I'd like somewhere in the ballpark of 1 to 3 hundred, but kind of expecting something in the 4-5 hundred range. Thank you!

megiddoblades said:

Also, what diameter insertable endmill would you recommend? I was thinking a .625 or.750 but not sure if it's strong enough.

Click to expand...

I wouldn't recommend ANY insert mill under 1".

What are you going to gain over a solid?

The steel body is going to be floppy compared to a solid carbide.

You are going to have less flutes, 3 if you are lucky, possibly only 1 depending.

You will be limited on depth of cut, the depth of the insert, not the flute length of the cutter.

97% of the time an indexable will eat more power than a solid. The geometry dictates that.

Your wall finish is going to suck.

What happens when you have a "woops". You destroy a bunch of inserts and lose a cutter body.. With a solid,
there is a chance it might be able to be resharpened, and at worst you are out the cost of the endmill, which will
be less than the cost of the cutter body, never mind the inserts.

megiddoblades said:

Thanks for pointing out the site, ezduzit!

It seems like a great place for choosing an insert type, and seeing the shapes and what they're good for was pretty cool.

Looking at the page here:
http://www.carbidedepot.com/formulas-insert-shape.htm
When it says limited machine power, does that mean if you go heavy DOC(say .1) it would tend to break?

Unfortunately, it doesn't seem to cover much about tooling manufacturer's, what toolholder's shape is adequate for certain ops, if faster feed types (low DOC) are faster overall at removing metal and leaving a decent finish.

Also, what diameter insertable endmill would you recommend? I was thinking a .625 or.750 but not sure if it's strong enough.

Thank you very much for your time!

Click to expand...

You'll notice the inserts listed as suitable for limited machine power are the ones with a smaller included angle of the cutting edges. This smaller angle has a chip thinning ability and reduces load on the machine. An Additional benefit includes lighter cutting pressure (vibrational tendencies) at the expense of a weaker cutting edge.

Generally for the work we do we're a Sandvik shop when it comes to indexables but I might go another way if I were starting over from scratch; however, we are so grandfathered in it would be difficult to switch at this point.

Thank you guys!

Bobw, by your post, I hang my hat and say I'm a victim of my own misconceptions.

You addressed practically every unstated thing (and then some) I thought the insertable types would be better at. What I was looking to gain over solid, is flexibility in carbide inserts, i.e. switch from aluminum inserts to steel depending on the material, fewer loops and passes, economy (couple fifteen dollar inserts, rather than a new, 80+dollar .75 em {no sharpener at school, and surf.grinder has no diamond wheel}). But more than that, was also expecting a better depth of cut, similar/better finish to solid, wasn't sure about deflection but thought it would be tougher to break, etc. Thank you for addressing that.

With a new (or at least lightly used), solid, half inch carbide endmills, and flood coolant, and could only get about .050 depth of cut on aluminum. I started off at .1 and it sounded like it was on its last legs. Then again, it was a toolroom style cnc, so it might've been the machine and not the carbide.

From what it sounds like, insertable endmills then are more for large work surface areas, and stick with solid everywhere else?

@Michiganbuck,
Interested newbie syndrome, sorry. So even the tool bodies of the insertable tool holders are material specific? I thought wrongly inserts would bridge the gap.

@Hazzert
Thank you, that helps clarify things! Those types would probably be better for smaller machines then. Makes sense...It's unfortunate that tooling companies locked you in. I suppose it all depends on your dealer, support, time constraints, locale, and personal preference and pray that the company doesn't shoot itself in the foot later on.

Thanks again for all your help guys, God bless you fellas for your patience!

Not just for smaller machines, they're also used for smaller or more delicate workpieces where deflection is an issue. The smaller the included angle the lower the cutting pressure and the smaller the tip radius the smaller the tip pressure again.

The worst case scenario for pressure would be an R type insert feeding the whole radius. That said the same insert only 10% Radius deep you could feed the snot out of due to the thinning action of the profile.

Although I agree with Bobw in that it is cheaper and more cost effective to buy one solid carbide tool than it is to buy multiple inserts and a "floppy" cutter body. You have to keep in mind that even though you can use indexables to finish machine they are really more suited to roughing and if you break an insert you need only to replace it as opposed to having to wait for the cutter grinder to fix it up again for you. There are indexable tools that do allow for hefty cuts such as a solid tool and are very versatile not to keep name dropping but the AQX style indexable cutters from Mitsubishi offer a lot of variety in their capabilities and you can get them in .750 diameter which is a good middle of the road for roughing I think. Like I said I agree with Bobw economically a solid tool is cheaper and maybe slightly more adaptable to everything but with a level of time and care you may find the indexable tooling to be just as much a match for a solid tool. Let's not forget a solid carbide tool does not allow for flex as opposed to a cutter body which will "give" alittle which can be paramount in a heavy cut as a solid tool may just snap. My .02

Good to know Hazzert, that seems like a really good rule of thumb, because believe it or not, I was scratching my head thinking, "how deep can each of these things go?" Probably not the .6 they said for max depth, but wasn't really sure. Tried a .1 cut on a monarch lathe with a tpg insert, and while it cut, it burnt through the insert pretty quick. That had to be one of the starting points of my obsession with carbide however (went from 'heavy' .02 cuts with hss).

Whysosharp, yeah, the 'floppy' caught my attention too! Thought that was a pretty, dare I say cute, description (sorry Bobw, but it was). We machinists(even student ones) have such a different view compared to the rest of the world, another reason to enjoy the field.

And thank you for your detail in key differences in strong points, and as to the aqx... 0_0 Those are powerfully flexible tools. Do you know what kind of deflection do you get? What size do you use? How long have you had them? From what I understand, the offset flutes reduce chatter, but do they also tend to walk (I'd imagine not if you swear by them, but curious)?

Sorry for the slew of questions there, but that was what I was looking for in an insertable. If we do large parts that would require a 3/4 or larger endmill, that's the main one thus far that I'd be looking at.

Thanks again guys, it's really awesome to be hearing from pros in the field!

megiddoblades said:

Thank you guys!

With a new (or at least lightly used), solid, half inch carbide endmills, and flood coolant, and could only get about .050 depth of cut on aluminum. I started off at .1 and it sounded like it was on its last legs. Then again, it was a toolroom style cnc, so it might've been the machine and not the carbide.

Thanks again for all your help guys, God bless you fellas for your patience!

Click to expand...

.
.050 doc with 1/2 dia em milling aluminum ? i would ask feeds and speeds used and if slot milling or doing 75% width passes. and most important length of tool sticking out and length of tool holder. also end mills made for aluminum can easily cut 200% faster
.
any slot milling the chips need to get out of the way. often a 2 or 3 flute endmill is better as too many flutes the chips just clog up the flutes.
.
slot milling or full cutter width milling it is normal to use reduced feeds and speeds and depth of cut compared to light peripheral or side milling
.
also quite normal to use a roughing endmill for roughing then use a different tool for finish passes.
.
for example i often use a 1.75 dia roughing endmill with a 1.75 depth of cut at full cutting width and just plow through a casting lug no longer needed at 5 ipm. sure feed not high but it plows through it all in one pass. of course that takes some horsepower

In the way of deflection I've seen anywhere from .001-.003 with the APX3000 style as for the AQX model given that I haven't played with it a lot from a job I just used it on I saw about .002 deflection consistently at .465DOC and .1875WOC. This was in a mid 1980's Supermax Rebel-1. Considering this measurement was taken with calipers it may have been more or less but we use indexables for roughing only so as long as the part isn't wildly tapered deflection isn't something we really look at with our roughers. We have a 3/4" one now I'm looking at a 1.0" but we have multiple APX3000 of different flavors the 1.0" and 3/4" are both great for ramping a profile into a part and though I'm sure someone has done faster we typically exceed 140ipm roughing with these at a 5* ramp angle .125 DOC(not special but most our work fits on common stock sizes so there isn't really ever a need to take heavier cuts. I'd be happy to help you make a selection if you really want to go the indexable route but my opinion is biased as I've only used Mitsubishi milling cutters. GARR makes a nice aluminum specific Endmill if you want to go the solid carbide route.

@DMF_TomB
I'm not quite sure, it's been some time (probably 4+months) and I'm kind of fuzzy on all the details. Also, I don't have my programs on this, but now that I think about it, I was probably milling mild steel (sorry about that, thanks for the tips though!), full width, 4 flute in a cat 40. That being said, I still, well, at least think (ahh, there's the trouble.^_^) I should've been able to do it no problems. Going by memory now, but the tool stickout was about 1.75, I normally use the Weldon if available, but always have the tool up to the flutes' beginning. As to the special aluminum endmills, hey, I just got a HSS rougher, I do need some time to catch up with you guys. ;P Good to keep in mind for the future though. On another note, I've heard those types tend to want to 'unravel'. Is there something I'd need to keep in mind for using them? Kind of OT, but...

Also, still trying to learn my way around taking into account some of the variables in the feeds, speeds beyond the basic calculations. DOC, coatings, rigidity (part and machine), Chipload PT (can't find for atrax endmills for some reason), coolant, length of tool, axial and radial cuts, certain sounds the cutters make for judging whether not to pick up the rpm (except chatter), I have no clue on. I blindly grasp for robin blue chips for carbide, and straw color for HSS. The closest thing I can sort of find for other endmills are chipload, coatings (i.e. tialn *.3), and coolant (think you can up by another 10-20 percent). I know that shows how little I know, I'm sure that doesn't even touch the surface, but that's why I appreciate all your guys input. But otherwise hoping by the grace of God to give my all and learn more!

And holy crap on that depth of cut! Wow, that carbide, I can't imagine how it must've been using HSS all the time. I wonder if future generations will wonder that about carbide some day, haha.

@Whysosharp
Wow, thank you so much for the info, that's pretty dang awesome. Either way, both seem to have astounding results for you. It really is a tough decision between solid and indexable, and each have their place for sure. Unfortunately I was ready to write solid off until Bobw mentioned its strengths, and then your views on insertables made it an even tougher choice.

What I'm doing in school, varies. For this semester, we're primarily cutting aluminum , however, we're also going to be machining jigs, fixtures, graphite, and unknown next semester. For personal projects, I'm probably going to be machining brass, 4140, cold & hot rolled, etc. I've gone through all my HSS 3/4 inch, and it was strongly recommended to us to switch to carbide now that we're solely on cncs. There's some talk about the shop eventually getting a tool and cutter grinder and maybe teaching how to sharpen an endmill. But I'm not sure how certain it is, and if it will be this semester, next or when I leave the shop.

So in short, Whysosharp, I'm going to take you up on your offer, and your bias is no bother!

I'm machining a variety of materials, it would mainly be used for roughing, I'd want to be able to use the endmill in multiple operations like you can a solid carbide one (facing, ramping, helical and profiling). It'd be awesome if at all possible, it could fit in an R8 collet. Here come the slew of questions again.

Does Mitsubishi stand behind their products? I know you use it for roughing mainly, but is the finish alright on lighter cuts? Do the inserts last basically as long as a standard carbide endmill (assuming you can't sharpen the endmill?)? It seems like the AQX is more flexible than the APX, but the APX is more rigid, is that true? On non typical insert, is there a way to find out the cutting angles?

Frankly, I've been amazed at the amount of knowledge here, and I thank the Lord for you guys. Seriously, in a day you guys changed how I approach selecting a machine's tooling, adjust the program accordingly and cleared up misconceptions along the way. Thumbs up to all of you!

Might've missed it but I didn't see anyone mention the overall tool length. I needed to machine a 4" deep profile in aluminum, and let me tell you solid carbide that long gets really expensive. It was cheaper to buy a 3/4" single flute indexable kit than a single reduced neck long reach end mill. I was very happy with its performance.


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I just see several things that nobody has mentioned
1. What's the HP of the machine that you're going to run these cutters in?
2. What's the spindle type and size (CAT HSK etc)?
3. What's the max RPM?
4. What's the max depth you need to cut?
5. What's the narrowest width you need to cut?
6. What type of coolant system?
7. What type of coolant?
8. Exactly what alloys do you intend to machine?

That should be enough for now. Without all of the facts, I don't understand how anything can be recommended. Without facts, you're just stating opinions. The OPs questions are so open ended, it's like saying "I need tires for my truck, what should I buy?" You'll get 100 opinions.
JR

@kineticmx,
Thank you, that's a good point to consider!

@JRIowa,
Thank you, you bring up good variables I should've addressed. I'll try and go point by point.
1. HP varies pretty significantly, anything between a 3 HP toolroom style VMC, to a five axis horizontal (ohh, what I have planned for you, heheh, don't tell it that though), and we'll rotate week by week. Probably averages around 30 hp if I had to guess.
2. Main spindle types are ER collets (30-50), and cat 40.
3. RPM varies from machine to machine, so I don't know for sure off hand, I want to say 6-7k.
4. Unknown on max DOC, we have multiple projects, and will design our own primarily this final year, though the longest depth of cut thus far would be 2.5 inches, but am compensating by flipping the part. Long shanks would be nice if they could fit through the cat 40 and only stick out as much as necessary
5. Much too small for indexables! I have some solid carbide already, some stubby, etc. but nothing above .5, save hss.
6. Mainly flood, but also air, and no coolant.
7. I couldn't tell you to save my life. It just stinks after awhile. Rust forms pretty quick, it's sticky when dry, greenish blue in color, and did I say stinks after awhile? Guessing water based, but I'll have to ask.
8. Varies from part to part, primarily aluminum this semester, but also tool (A2) steel, brass, hrms, 4140, etc.
9. Adding one here, but we'll also have to machine 3d text and shapes via Gibbs.

I was going for narrowing some tried and true tires there. ^_^ Thanks again!

1. Found out about HP, 15 is average
3. Max RPM varies to 6k to 7500
7. Oakflo DSS 700

I am a job shop and run very little indexables on the mill. In fact, the only indexable in my mill is a facemill. IMO indexables are great if your running production but I have little justification in buying bodies and inserts when my tooling varies so much. I just spent $400 on a indexable drill and .759" inserts for a stainless job. Now that drill sits and collects dust. The only time I will use it again is for drilling more than 5XD because my HSS drills are considerably cheaper to run.

Another thing to consider is your experience. Indexables can be cheaper in the long run, but if you crash you might be out the body too which is the expensive part. Just get a good set of carbide endmills that have good geometries and coatings. Look into Swiftcarb for aluminum. For steels I run the new Guhring Diver endmills. I've drilled and bored over 800 holes with a single Diver endmill and still ran it at 900 SFM afterwards before it started mircofracturing.(new product, had to R&D it!)

If you don't have coolant thru or air thru your not going to gain much vs. running a nice carbide endmill IMO as chip clearance would be an issue too.

If your not sure about your coolant, get knowledge on it! Coolant plays a huge factor in machining, especially aluminum! You can have the best cutter in the world, but if you clog and burn it up they are all worthless in the scrap bin.

In my opinion if you want to invest in an indexable I would look into a facemill and/or chamfermill. These are two cutters that will almost ALWAYS used in any machining operation so they will always be used and not tossed in the back of your tool chest. With a CAT40 and average 15 hp I would say a max 3" dia 4 or 5 flute facemill. 45 degree inserts are great especially for low HP mills.

From my experience I would stay away from Kennametal. They use to be good until they went across seas. I have a few indexables and am not impressed with their tolerances.

Ouch. I appreciate you sharing your experience with those types of drills.

Thank you for bringing that up, it reminded me of a question to ask. I don't understand how a solid carbide is a better economical buy unless you have a tool/cutter grinder, then you can buy used and do even better. If a reasonably priced, good quality solid carbide, its price is probably hanging around 150. (I've seen 3 hundred even!) New, name brand, probably decent quality insertable mills start at 250-300. If the inserts last about as long as a solid, and each dulled at the same time, you're probably buying 70 in inserts, vs. 150 for a new endmill. You're just about breaking even the first time the inserts are replaced. Which brings me to the question, how long do inserts last in comparison to solid types?

Good to know.

Checked into it a little more, it's a medium duty, oil based, semi synthetic oil, made for general purpose.

Thank you for your suggestions on facemill and chamfer mills, as well as size, and brand to avoid. I'll keep it in mind! Take care jbifs.