There are about a dozen defects that can occur during drill resharpening
(repointing). About half are major, the other half are not as important.
Most drill suppliers have a chart of one sort or another, some shops inspect
drills for these, all good repointing services do this. Talk to your
supplier and or repoint center, if they can't help ask their competition.
This is a case where pictures are worth a thousand words.
Defects can affect hole-wall quality, tool life and positional accuracy on
small drills.
Remember that resharpening is really only a regrinding of the tip, the sides
of the cutter are not touched, and may dull through use. This is not
normally an issue with FR-4, although more exotic materials, like PTFE for
example, are more sensitive.
Drill smear is removed through normal processes, there are a few in common
use such as permanganate and plasma, most multilayer shops perform this pro
forma, hence epoxy smear is almost never an issue these days. Smear does
not cause a problem on double sided plated through holes as the plating will
always connect to the cladding at some point, it is only an issue where it
isolates connections to internal layers, which by their nature have a small
interface area with the PTH barrel.
Ian
-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of <Peter George Duncan>
Sent: Thursday, April 26, 2001 4:51 AM
To: [log in to unmask]
Subject: Re: [TN] The standard bit inspection spec
Hi, again, Jay Ju,
Defects to the bits themselves shouldn't amount to more than insufficient
sharpness of edges, though incorrect angles are also not unknown. Ceramic
bits can be chipped as well, but I can't think of much else off hand. You
may get better answers from other Netters.
Regards
Pete
Young Hwan Ju
<yhju@SIMMTEC To: [log in to unmask]
H.CO.KR> cc:
Sent by: Subject: Re: [TN] The standard
bit inspection spec
TechNet
<[log in to unmask]
ORG>
04/26/01
04:18 PM
Please
respond to
"TechNet
E-Mail
Forum.";
Please
respond to
yhju
$)CThank you for your useful and prompt response.
Yes, Pete I am talking about drill bits for PCB fabrication.
And what I want to know is what kind of bit defect is likely to happen by
incorrect resharpening compared to new bit production.
Regards
Jay Ju
----- H8<[GQ ;g6w : YoungHwan Ju/SimmTech ( 2001-04-26 05:17 PM ) -----
peter.duncan@s <v=E@N : "TechNet E-Mail Forum."
<[log in to unmask]>, [log in to unmask]
t.com.sg B|A6@N :
A&8q : Re: [TN] The standard
bit inspection spec
2001-04-26
04:56 PM
Hi, Jay Ju,
Are you talking about drill bits for PCB fabrication? If you are, I cannot
give you an inspection spec number, but major defects caused by incorrect
resharpening might include incorrect hole size and smearing of the hole
walls. Smearing will have to be cleaned up by reaming the holes prior to
plating or you will not achieve proper connection to inner layers, good
plating adhesion or even plating thickness.
If the bits are for a different application, please specify what it is.
Regards
Pete Duncan
Young Hwan Ju
<yhju@SIMMTEC To: [log in to unmask]
H.CO.KR> cc:
Sent by: Subject: [TN] The standard bit
inspection spec
TechNet
<[log in to unmask]
ORG>
04/26/01
02:08 PM
Please
respond to
"TechNet
E-Mail
Forum.";
Please
respond to
yhju
Hi, all subscribers
In incoming inspection of both new bit and resharpened bit, Can you make
me know the standard spec if anyone knows about that.
And I' would like to know the exclusive major defects caused by wrong bit
resharpening operation.
regards
Jay Ju
----------------------------------------------------------------------------
-----
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt delivery of Technet send the following message: SET
Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
----------------------------------------------------------------------------
-----
----------------------------------------------------------------------------
-----
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt delivery of Technet send the following message: SET
Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
----------------------------------------------------------------------------
-----
----------------------------------------------------------------------------
-----
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt delivery of Technet send the following message: SET
Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
----------------------------------------------------------------------------
-----
---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------
|
