Use carbide drill and reamer! Allow only 0.3mm stock for reaming. Use proper tool holders with min runout. 400C you have is nothing for carbide but can be high for standard (junk M2) HSS tools.
Viktor
http://viktorastakhov.tripod.com
EdDanzer (Mechanical)
Viktor,
If you read my post we do use high tech drills when the task justifies. Do you also model the thread helix, dimension the thread angle and radius at the thread point?- unfortunately not although a lack of such models creates some problems when we use rigid tool...
KENAT (Mechanical)
"DO NOT BREAK THRU" - is an atavism from the time when we did not use CAD drawings. Nowadays, a normal drawing should show everything graphically with tolerances. For example, in the automotive industry in drawings of the valve bodies, pump covers and other parts of an...
[highlight #F57900]In this case, a note saying drill shall not penetrate this surface would be sufficient.[/highlight] - this is a new trend in ISO drawing standards? The drill may not penetrate a dozen of other surfaces - do I need to make a note for each? :) Be serious - there is no such a...
SpaciouS (Mechanical)
If cost is not a big factor than you have another game. First of all, select a good tool maker who has high-precision grinding machine and Zoller genius 3 (or Walter Helichek Pro); make sure that they grind the tool in the holder as a monoblock and then check the resultant...
SpaciouS
"Radially symmetric features can generally be made more precisely on a lathe than from a milling machine (I believe)" - believe sounds as church activities whereas guess relates to Las Vegas. It does not matter what type of machine we are talking about. Rather, it is a mater of...
Can I achieve +/-1um [.00004"] bore size, and +/-5um [.0002"] coaxially from one bore to the next inline, using a milling machine?
No - you can't. Typical spindle runout+tool holder runout+tool runout+...are much greater.
EdDanzer
In general, you are right. However, two points I would like to make.
First, as the conditions have been changed, the tool should be changed accordingly. This is not nearly the case.
Second, no need for cost justification. It is to say that when you grind a complicated point geometry...
cloa
Sharpe and Morse did a great job under conditions of the second half of the 19th century. However, "the best result" as vied today should be specified clearly. the best in terms of what - hole quality, productivity (the penetration rate0, cost per drilled hole, tool life and so on. "The...
Ted
You are right - it is established long time ago that 120 presents a balance. However a question remains: Why? An why modern carbide drills by leading tool manufacturers as for example Guhring and Mapal are supplied with standard 140?
Not that something has been changed since 1888 in terms...
New Post cloa (Petroleum)
Not even close. 140 is now the standard for carbide drills while 120 is still the standard for HSS drills. When you say "minimum force'? what the force you mean? When you say "maximum cutting" what is that? Being of great importance, the point angle is the second most...
AX3L
To select the right direction, you have to know the application. It is first of all the drilling system you are dealing with. In the automotive industry, new machine come with powerful high-speed spindles having built-in censors and Siemens controllers that cleanup the signal so that the...
Well..the story is as simple as....I will start to tell it in sections a bit later. To start, please think that what changes with the point angle: the direction of the chip flow with respect to the drill axis; the ratio "axial/radial" forces; the chip load on the major cutting edges (a.k.a. the...
Power measurements and power limits set on the machine controller - this is the right answer. Anything else that far is a toy.
Viktor
http://viktorastakhov.tripod.com
118-120 is the standard for HSS drills. Nowadays leading companies use 140 for carbide drills.
A question "Why?" is another story - the above link does not provide clear answer although it rather simple but lenghly to explain with no figures.
Before you try to figure out about the coolant application, you should first to know if the drill geometry and carbide grade are suitable for the work material. Coolant-through drills performs ALWAYS better that those with flood coolant provided that drill geometry, machining regime, tool...
To the first approximation
Cutting force = uncut chip cross-sectional area x compressive strength of the work material.
Approximation is fairly good.
Viktor
http://viktorastakhov.tripod.com
Tom
I haven’t heard anything about this conference though I wouldn’t mind to read its proceedings. Just as bed (or bad?) time stories with the corresponding pictures of the other side of the Moon (sorry, micrographs SEM images of structures which nobody normally can understand).
As for my...
ISO insert codes that describe the insert geometry are good reference but ISO code of grades is of no use. Here are some of my comments on
STANDARD ISO 513:1991
Application of hard cutting materials for machining by chip removal – Designations of the main groups of chip removal and groups of...