Carbide insert question

[davidpbest]

Okay, the size of a 215 insert is .250" inscribed circle. A triangle needs three sides being .433" long to contain a .25" circle.
Spilt in two so we have a hypotenuse of .433" and an opposite side of .2165". So that makes the adjacent side or the length of a 215 insert ~.375." long.
Somebody feel free to peer check me.

Excellent math:

 

[Mike8623]

Pardon me guys, if the hole was .313, what size would that make the length?

 

[ddickey]

Do you mean the inscribed circle? An insert with an inscribed circle of .3125" would be
.460" long.

 

[Mike8623]

Yes

 

[Mike8623]

I want to really thank all of you. I kinda understand this stuff, but then something else pops up and messes it all up for me.

I'd really like to find a insert as follows:

T- triangle
P- 11 degree relief or just a little more
G- doesn't matter, less the better
H- i need a counter sink hole for cap
screw

2- would really, really like a 2.5 hole .312-.313
1- 1/16 or 1/8 would be fine
5- 5/64 radius is fine

 

[Mike8623]

My work bench is just full of paper trying to figure this thing out

 

[davidpbest]

I want to really thank all of you. I kinda understand this stuff, but then something else pops up and messes it all up for me.

I'd really like to find a insert as follows:

T- triangle
P- 11 degree relief or just a little more
G- doesn't matter, less the better
H- i need a counter sink hole for cap
screw

2- would really, really like a 2.5 hole .312-.313
1- 1/16 or 1/8 would be fine
5- 5/64 radius is fine

If by "hole" you mean the inscribed circle (I.C.), then the ANSI designation code for the insert you seek would be as follows:
TPGH2.515 for 1/16" thick
TPGH2.525 for 1/8" thick

It might exist (but I doubt it) in metric form with an ISO designation of:

TPGH100120 < the 10 is 10mm side length (equivalent to ~0.4"), the 01 is 1.59mm thickness, the 20 is 2mm radius
TPGH100320 < the 10 is 10mm side length (equivalent to ~0.4"), the 03 is 3.18mm thickness, the 20 is 2mm radius


The tightest tolerance would be an "M" and designated TPMH.

I'm not sure such a thing exists. TPGH inserts typically have an I,C. of 0.250" or 0.375". If a TPGH insert exists with an I.C. of 5/16" (0.3125"), that would be news to me. I recommend you call Carbide Depot and discuss this with them. If such an insert does exist, they will know.

 

[Mike8623]

I think you are right, I've searched and searched

 

[Mike8623]

What would the numbers 21.50 mean in
TPGH21.50?

 

[ddickey]

That would be size of 2 so 1/4" inscribed circle.
1.5 thickness of 3/32".
0 radius which is .004"
Did you see this insert somewhere?