03-18-2013, 07:26 PM
(This post was last modified: 03-18-2013, 07:29 PM by the penguin.)
I have 4 different set of carbide insert boring bars, 2 made in the US and one made in Poland and the final one made in Taiwan. Two of the sets use CCMT inserts (21.51 and 32.51), one of the set uses TPGB inserts (221 and 321) and the final set uses TT type inserts (221). All of the sets have flat bottoms, tops and sides, on the rounded shaft so the can be used in the standard QCTP blocks. All of the tip observations are based on using the standard QCTP tool block.
On the CCMT boring bars, both of the sets, the insert has a slight downward tilt (5-7 degrees) in the front, but one set the insert is level, side to side and on the other, there is a similar tilt down on the cutting edge side (again about 5-7 degrees). Which one is right or doesn't it matter.
The set that uses the TPGB inserts, the insert is almost level front to back and side to side.
The set that uses the TT stype insert, the insert like the one for the CCMT is tilted dow in the front (again about 5-7 degrees) and with about half of that tilt (2-3 degrees) toward the cutting edge.
When I use the QCTP blocks that made for boring bars with the pinch sleeves, obviously the insert can be orientate anyway, up or down. I realize that the boring bars have different inserts and are made by different mfgrs, since I almost alway using the boring bar QCTP block, where is the best spot of cutting tip location, or is it dependant on the type of insert used. Any rule of thumb or guide line would help.
This topic came up in conversation today with a fellow home shop guy and neither him or me had any concrete data to base a solid conclusion on.
On the CCMT boring bars, both of the sets, the insert has a slight downward tilt (5-7 degrees) in the front, but one set the insert is level, side to side and on the other, there is a similar tilt down on the cutting edge side (again about 5-7 degrees). Which one is right or doesn't it matter.
The set that uses the TPGB inserts, the insert is almost level front to back and side to side.
The set that uses the TT stype insert, the insert like the one for the CCMT is tilted dow in the front (again about 5-7 degrees) and with about half of that tilt (2-3 degrees) toward the cutting edge.
When I use the QCTP blocks that made for boring bars with the pinch sleeves, obviously the insert can be orientate anyway, up or down. I realize that the boring bars have different inserts and are made by different mfgrs, since I almost alway using the boring bar QCTP block, where is the best spot of cutting tip location, or is it dependant on the type of insert used. Any rule of thumb or guide line would help.
This topic came up in conversation today with a fellow home shop guy and neither him or me had any concrete data to base a solid conclusion on.
jack