Drilling oversized and drilling undersized on Fanuc machine?

[Dbrock11]

Drilling oversized and drilling undersized on Fanuc machine? I've asked before but I can band-aid this by slowing down feeds and speed. Just want to know the cause my drill is size is 8.542 and my reamer is 8.792. The runout is 2 or 3 microns on the end of the drill and reamer. Here is a video if its undersized its usually just 2 holes are tight, if its oversized either all or just one. Most of the undersized holes are the holes on the bottom side.

 

[mfgenggear]

OP
I try to explain.
Many factors.
#1 factor is the wear and tear of your machine.
The higher the force and rpm will cause movement.
The precision of the tools will depend the precise manufacturing of tools, and materials used.
Not all tools are equal same goes for machining centers.
There are different classes of precision.
Machine tools and machining centers
Are normal, precise, and ultra precision.
As the precision goes up the the feed and speeds slows down.
Thus when precision is required cost goes sky high.

 

[Dbrock11]

In order to correct material moving, what would you do lower the feed and speed?

I know essentially, you don't want any movement.

However, to counter from machine not being 100% efficient as far as drill walking would this method help?

 

[mfgenggear]

OP
the type of work , size of holes or machining , the hardness and type of material.

follow standard feeds and speeds as specified in machinery hand book and from tool suppliers for their tooling
use brand new sharp drills and mills on critical parts, must not use sharpen tools, if not done correctly
such as drills with over size holes.
use the correct type size, coated or not coated carbide inserts. obtain from your tool sales engineer for correct feeds and speeds.
any chatter slow feeds and speeds down with over ride of the feeds and speed of the machine centers.

there are different rigidity of machining centers and tooling used for machining, tool adapters, holders etc.
amount of horse power and rigidity will dictate depth of cut and feeds.

 

[enginesrus]

If you need very close dimensions then use a different process to finish the holes.