# Trials and tribulations of insert decoding



## GunsOfNavarone (Jan 16, 2020)

I'm not gonna lie, of all the mill/lathe knowledge I am slowly learning, insert decoding just IS NOT coming together for me. I have done times of searching, a lot of chart scanning, sat on the couch with a caliper measuring and cross referencing....but yeah, I'm not going to lie, this is NOT coming together for me.
I have talked to other newbs, this isn't uncommon. I will say it is more complicated than it needs to be and that there are ANSI and ISO, it makes it even more challenging. Here's my story, names have been changed to protect the innocent.....
I bought my lathe about 2 years ago, with good recommendations, I immediately changed to an AXA QCTP. I bought the Accusize 3/8" tool holders and in this time, I have needed to change the inserts. I want better quality inserts than the originals and I do mainly stainless. The C shaped insert tool some education, but was able to get a few different Kennametals. Done. This W shaped one has become comical in trying to replace it. I have been using it for 2 years and that has been through the earliest learning stages where uber light passes was about all I did, now I have learned that can actually over heat the tool...but I'll try to keep this in topic and wrap it up.
My first (extremely under thought through) purchase was WNMG inserts. Way wrong. My tool holder is swgcr06-2j and Accusize says WCMT 21.52 inserts. Went to ebay and found some really good ones,got them....too small. The sellers said you need WCMT 32.52 he did a swap with some addition cash and I got some SECO for stainless. Too big. I'll say there are more options in the ANSI name than the ISO, but they should be one and the same....NO?
I need help with this tool holder. Good, bad or indifferent, I'm not going back to ACCUSIZE. Maybe it's just pricip


----------



## Liljoebrshooter (Jan 16, 2020)

The best information I have found and made sense is  carbide depot.   Click top right, three lines,  then technical resources.
Then about half way down that page it will list several items.  Insert designation chart is on the right.  It shows what each number and letter means.
In the same list is the cross reference for ISO also.
They also show the same information for tool holders and boring bars.
If you have already looked at it,   sorry about being late.

Joe Hynes


----------



## GunsOfNavarone (Jan 16, 2020)

Thanks Joe. I have printed that out (a long time ago) along with Mitsubishi 's and a couple others. I have still ordered the wrong thing and even with a professional info, the wrong thing. I'm outta ideas to be honest. I'll measure it all up again (7th time?) And post my results here. It seems unless I purchase Accusize's inserts (that I don't want) I'm up a creek. Something isn't jiving for some reason.


----------



## ub27Rocks (Jan 16, 2020)

Accusize catalog says the insert is WCMT2.52, e.g.  https://www.prolinemax.com/10-PC-WC...able-Turning-Tool-Bit-Chipbreaker_p_2075.html Do those dimensions jive with what is in your holder?


----------



## GunsOfNavarone (Jan 16, 2020)

So, i can confirm it is wcmt. Beyond that, I feel like it's all a guess/round to the closest option.
Inscribed circle. It's not asking for size of hope but rather the biggest imaginary circle that would fit within insert? If so, the IC is 7.6mm or .299" that does relate to a 1.5, or a 2 or a 2.5
It can't be that much of a rough guess system. This is the 1st issue.


----------



## mksj (Jan 16, 2020)

Basically that particular holder uses a weird insert somewhat unique to that holder, the more common insert would be the WNMG (negative rake) as opposed to WCMT (neutral rake) insert. It is also a screw insert as opposed to the clamp style for the WNMG and the smallest size is 3/8" inscribed circle, the WCMT would be a 1/4". So it does not look like you have many other options for that particular holder. ANSI and ISO are interchangeable, just a different measurement system, ANSI being more archaic. It looks like the Accusize insert spece'd is a unique oddball, doesn't seem to follow the proper nomenclature. A standard would be WMT or  WCGT 040204 21.51 Carbide Inserts with a 6.35mm inscribed circle, so Accusize seems to have their own flavor insert (it may be an 05 size, 7.94mm inscribed circle)  is the reason you cannot find any better replacements. Depending on your size machine, for an AXA you might try 1/2" set of holders that use some more commonly available inserts. I have attached the more common ones that I use sized for a BXA holder, each holder specifies the type and size insert to uses. Then I look up the manufactures insert specifications for the material I will be using them on. Some of these are shown in the attached document. On a smaller lathe you probably want to stick with neutral or positive rake holders unless turning softer materials.

ISO Inserts,


----------



## GunsOfNavarone (Jan 16, 2020)

mksj said:


> Basically that particular holder uses a weird insert somewhat unique to that holder, the more common insert would be the WNMG (negative rake) as opposed to WCMT (neutral rake) insert. It is also a screw insert as opposed to the clamp style for the WNMG and the smallest size is 3/8" inscribed circle, the WCMT would be a 1/4". So it does not look like you have many any other options for that particular holder. ANSI and ISO are interchangeable, just a different measurement system, ANSI being more archaic. It looks like the Accusize insert spece'd is a unique oddball, doesn't seem to follow the proper nomenclature. A standard would be WMT or  WCGT 040204 21.51 Carbide Inserts with a 6.35mm inscribed circle, so Accusize seems to have their own flavor insert (it may be an 05 size, 7.94mm inscribed circle)  is the reason you cannot find any better replacements. Depending on your size machine, for an AXA you might try 1/2" set of holders that use some more commonly available inserts. I have attached the more common ones that I use sized for a BXA holder, each holder specifies the type and size insert to uses. Then I look up the manufactures insert specifications for the material I will be using them on. Some of these are shown in the attached document. On a smaller lathe you probably want to stick with neutral or positive rake holders unless turning softer materials.
> 
> ISO Inserts,
> View attachment 310841


THANK YOU! Yes, it seems to be VERY limited. I had posed that question long ago, can I go to a larger holder that will take a insert that is more common with more options. It seems If I go to a 1/2" holder, i will be above center of work piece. I may just go this route and mill down the bottom side of holder, or do I go with an XL AXA tool holder and mill it down even more. I understand my mill doesn't have the power to do negative take inserts, but there are probably options in positive take in the 1/2 or 5/8" holders? I am not happy with my option in the trigon 3 /8" options so. ....


----------



## mksj (Jan 16, 2020)

AXA are designed to take 1/2" tooling in their holders, I would stick with 1/2" unless you have a small lathe. You can mill the holders and/or use spacers, but the outer surfaces of the holders are hardened (at least mine), so a bit difficult to mill (I use carbide end mills). You should be able to gauge off your 3/8" insert holders as to if you can lower the holder an additional 1/8". You adjust the height of the tooling holder so the insert cutting edge is on center. Typically an oversized holder is taller as opposed to thinner on the bottom.


			https://www.precisionmatthews.com/shop/250-101/
		



			https://www.precisionmatthews.com/shop/250-101-xl/
		


If you have a 12" lathe you may be able to fit 5/8" oversized holders where there are more insert options, smaller machine stick with 1/2" which should still should be able to use 3/8" IC inserts. On general machining I primarily use the CCMT/CCGT type inserts, WNMG I use in aluminum with ground edge inserts, but I do not recommend negative rake for smaller lathes. The other common styles are listed in the document provided, but there are many types. The nomenclature is like learning a new language, but once you get the gist of the names, sizing and coating it makes a lot more sense. I have certain inserts manufactures/coatings that I use, they work well for my application. In an industrial setting you are trying to achieve maximum production rate and insert longevity, so a totally different set of priorities and much larger/heavier machinery.


----------



## Mitch Alsup (Jan 16, 2020)

mksj said:


> AXA are designed to take 1/2" tooling in their holders,<snip>
> 
> If you have a 12" lathe you may be able to fit 5/8" oversized holders where there are more insert options, <snip>



All of my AXA holders take 5/8 or 16mm tool holders.


----------



## darkzero (Jan 16, 2020)

Mitch Alsup said:


> All of my AXA holders take 5/8 or 16mm tool holders.



The holders you purchased may but that is not the original Aloris standard. Aloris standard is 1/2" for AXA, 5/8" for oversize. 5/8" is standard for BXA & 3/4" for oversized. 

Newer Dorian holders jump up 2 sizes for their oversized holders, 3/4" for AXA & 1" for BXA. But just because you can fit the larger tools in one of these extreme oversized tool holders doesn't mean they will work with your lathe.


----------



## GunsOfNavarone (Jan 16, 2020)

I bought a HHIP 1/2" cutoff tool, even in the lowest height on the AXA holder, I had to mill off about 1mm just to get right at the center of the work. I have a Grizzly g0602z 10x22 lathe. I lean towards trying an XL AXA holder and jst seeing what works and what mods I need to make. All my other 3/8' tools, there are plenty of options, but I am limited on this WCMT. Maybe it's good enough, but since I'm still in the early stages, I'd rather build my inventory with what works for now and in the future rather then spending tons on 3/8' when I end up  at 1/2" or even 5/8". 
I'm buying an XL now and both a 1/2" and 5/8" unless there are any other thoughts...


----------



## GunsOfNavarone (Jan 16, 2020)

darkzero said:


> The holders you purchased may but that is not the original Aloris standard. Aloris standard is 1/2" for AXA, 5/8" for oversize. 5/8" is standard for BXA & 3/4" for oversized.
> 
> Newer Dorian holders jump up 2 sizes for their oversized holders, 3/4" for AXA & 1" for BXA. But just because you can fit the larger tools in one of these extreme oversized tool holders doesn't mean they will work with your lathe.


That's my concern. I guess there is only one way to find out for sure? I don't know if my HHIP cut off just isn't design on the low side, rather the high. Perhaps other tools will be better or worse.


----------



## darkzero (Jan 16, 2020)

GunsOfNavarone said:


> That's my concern. I guess there is only one way to find out for sure? I don't know if my HHIP cut off just isn't design on the low side, rather the high. Perhaps other tools will be better or worse.



Generally, with indexable tools the cutter height is inline with the top of the shank. But this doesn't apply to all tools like boring bars for example. To find out you will need to measure the distance from the top of your compound slide (surface the tool post sits on) to spindle centerline. You'll need at least 15/16" height to run 1/2" tools in AXA. If you don't have at least 15/16" than an AXA tool post is technically too big for your lathe. In that case you would have to mill material off the bottom of the tool holders, mill off the bottom of the tool shank, or run smaller shank tools.


----------



## GunsOfNavarone (Jan 16, 2020)

I believe AXA is correct for my 10x20 Griz G0602z...but I agree, that doesn't mean all 1/2" or 5/8" will work. I just placed an order for a 5/8" AXA hold and a 3 piece tool/cutter set (one tool is a WNMG) We will see where this goes and what I have to modify. I appreciate the complound to spindle measurement, I will check that now. I'll get it to work, but depending on how much modifying it takes, perhaps I will try 1/2" next. Nothing risked, nothing gained I guess, I just can't deal with that one tool having zero options on inserts. I'll keep anyone interested posted.
Thanks much guys!


----------



## Jericho (Dec 10, 2020)

My son just bought an Accusize mill cutter and I see what you mean about the cutters. Seems like Accusize has bastardized all the standard nomenclature and come up with their own rendition to keep you buying their inserts.  These are APKT11T3.Have no clue as to what the KT11T3 are supposed to translate to.


----------



## GunsOfNavarone (Dec 11, 2020)

Yeah, there are the ones they go by their own standards of jibberish, but I will say with time it gets a bit more easier to understand. I know this opens doors for “debate” but as usual, the metric side of things is a bit more sensical.


----------



## macardoso (Dec 11, 2020)

There are an absolute ton of different insert geometries. I'd categorize them as standard and proprietary. The standard inserts are available everywhere and are easy to find matching holders. Every manufacturer also has proprietary inserts. These are usually custom made to fit a specific tool or family of tools. Often they are targeted at a higher performance market who is willing to buy into the family of tools and supporting hardware. 

I'd recommend sticking to the common shapes and sizes. Here is an example list which is far from inclusive.

CNMG (Most common insert, general purpose, negative rake, high cutting forces, my 12x36 can barely handle these, CNMG432 is most common)
CCMT (Positive rake general purpose insert, my go-to, CCMT32.50 is my favorite)
TCMT (Triangle insert, often used on boring bars)
DCMT (medium diamond insert, weaker than CCMT, stronger than VCMT. DCMT21.51 fits some of my boring bars)
VCMT (sharp diamond insert, weak, but low cutting forces and excellent accessibility, ideal for fine finishing, VCMT110304 is my go to)
SCMT (square insert, used for heavy turning or chamfers)
There are metric and imperial designations. For example CCMT31.51 and CCMT090304 are the same insert. The first is the imperial designation (used by Shars for example) and the second is the metric designation you'll see on AliExpress.

Next are different edge conditions and rake angles. xxMT is common for general purpose positive rake inserts (e.g. CCMT32.50). xxGX or xxGT are uncoated, high polish, sharp ground edge inserts great for plastic or non-ferrous metals (e.g. CCGT090304). 

Finally, the corner radius is very important. In the imperial designation, the "31.5" is the insert size while the "0" is the corner radius (e.g. CCMT32.50 vs CCMT 32.52). "0" is a near sharp corner, "1" is a medium radius, and "2" is a heavy radius (manufacturers will provide the exact dimension. In the metric designation, the last 2 digits (e.g. "04" in CCMT090304) are the corner radius. "02" is near sharp, "04" is medium, and "08" is heavy. A heavy radius creates a stronger tool for roughing and ideally a better surface finish at high feed cutting, but tremendously higher cutting forces. A sharp edge will deflect the workpiece less, giving more accurate dimensions. The corner radius also determines the *minimum* depth of cut you can take. I strongly recommend the near sharp corner for machines under a 12" swing. I rarely use the medium corner inserts and only for roughing.

The included angle of the insert also determines cutting forces. The lower the cutting forces, the more accurate your dimensions will be after the cut. That is why the VCMT (30 degree included angle) will finish more accurately than the CCMT (80 degree included angle) in most cases.

The xxGT edge condition also drastically reduces cutting forces, but is a weak edge. They are ideal for soft materials (and have excellent life), but also give good performance in alloy steel and especially stainless, although they have a much reduced insert life.


----------

