Drifting of drilling bit

[terry]

Hi,

When drilling holes in PCB, drifting of drilling bit will make the
copper pad vanish, do anyone knows how to prevent this to happen?

I know the general method is to use shorter and smaller drilling bit.
Does the rotation speed affect the result?

Thanks!

 

[James T. White]

"terry" <leonlai2k@yahoo.com> wrote in message
news:9904d48.0409081951.37ea222d@posting.google.com...

Hi,

When drilling holes in PCB, drifting of drilling bit will make the
copper pad vanish, do anyone knows how to prevent this to happen?

I know the general method is to use shorter and smaller drilling bit.
Does the rotation speed affect the result?

Thanks!

Assuming you are etching your own boards, you might find it useful to put a very
small hole at the center of all the pads. If you get the size right, it acts
just like a center punch on metal and the drill stays in the center of the pad.
It also helps to have very, very sharp drill bits and get the drill speed right.

--
James T. White

 

[Clarence]

"James T. White" <SPAMjtwhiteGUARD@SPAMhal-pcGUARD.org> wrote in message
news:4143a5af$0$448$a726171b@news.hal-pc.org...

"terry" <leonlai2k@yahoo.com> wrote in message
news:9904d48.0409081951.37ea222d@posting.google.com...
Hi,

When drilling holes in PCB, drifting of drilling bit will make the
copper pad vanish, do anyone knows how to prevent this to happen?

I know the general method is to use shorter and smaller drilling bit.
Does the rotation speed affect the result?

Thanks!

Assuming you are etching your own boards, you might find it useful to put a
very
small hole at the center of all the pads. If you get the size right, it acts
just like a center punch on metal and the drill stays in the center of the
pad.
It also helps to have very, very sharp drill bits and get the drill speed
right.

--
James T. White

If your using re-sharpened bits, and who isn't? Be very careful to see to it
the center of the bit is really the center of rotation. We had this problem
and solved it by carefully inspecting the drill bit under a microscope and
rotating it in a mandrill to assure they are concentric on the center of
rotation. Made a BIG difference.

Also be sure the drill is turning at the recommended RPM and not loading down,
they tend to drift if the bit is binding.

 

[Watson A.Name - \"Watt Su]

"Clarence" <No@No.Com> wrote in message
news:t0Q0d.18590$lW3.2918@newssvr27.news.prodigy.com...
[snip]

If your using re-sharpened bits, and who isn't? Be very careful to
see to it
the center of the bit is really the center of rotation. We had this
problem
and solved it by carefully inspecting the drill bit under a microscope
and
rotating it in a mandrill to assure they are concentric on the center
of
rotation. Made a BIG difference.

Hah-hah-hah! I'd like to see you try to put a drillbit in a monkey's
nose!! Silly!

http://www.google.com/search?hl=en&ie=UTF-8&q=mandrill+definition&btnG=G
oogle+Search

Also be sure the drill is turning at the recommended RPM and not
loading down,
they tend to drift if the bit is binding.

 

[Clarence]

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com> wrote in
message news:10kj1j4s20d9sfe@corp.supernews.com...

"Clarence" <No@No.Com> wrote in message
news:t0Q0d.18590$lW3.2918@newssvr27.news.prodigy.com...
[snip]

If your using re-sharpened bits, and who isn't? Be very careful to
see to it
the center of the bit is really the center of rotation. We had this
problem
and solved it by carefully inspecting the drill bit under a microscope
and
rotating it in a mandrill to assure they are concentric on the center
of
rotation. Made a BIG difference.

Hah-hah-hah! I'd like to see you try to put a drillbit in a monkey's
nose!! Silly!

http://www.google.com/search?hl=en&ie=UTF-8&q=mandrill+definition&btnG=G
oogle+Search

Also be sure the drill is turning at the recommended RPM and not
loading down,
they tend to drift if the bit is binding.

You of course recognized the term from your family tree? Do they all have the
same purple nose? BTW: A MANDRILL is NOT a monkey!

The tool I have is clearly labeled MAN-DRILL as a contraction for "Manual Drill
holder!" It has a wood handle and a knurled ring used to rotate the bit.
Instructions for starting holes using the tool are included in the box it came
in.
The spell check apparently removed the hyphen!

Normally I would call this tool a Pin Vise, but those have no swivel to turn
the bit.