Your problem(s) are in drilling, and trying to correct deburring is not
a good way in a long run. I will look for:

- thicker entry material (use .008" or even .010", instead of .006-.007
aluminium);
- slower feed rates, but must check with drill vendor;
- good drill bits (make sure your re-sharps conform with the original
new drill bit);
- cleanliness of the panels; good tapping, or other system of fixing the
panels on drill table;
- good vacuum on drill machine;
- spindle alignment (perpendicularity to table, left to right & front to
back, as well as spindle height across the table);
- pressure foot damage.


Another $.02
Julian / [log in to unmask]





Lyle Anderson wrote:
> 
> We are experiencing sporadic instances of copper burrs after deburring.  It
> appears that the deburr brushes are "shaving" burrs and almost but not quite
> removing them.  Describing the condition as a burr may be misleading because
> most people think of a burr as protruded copper.  These burrs exist when the
> surface is 100% smooth and free of surface burrs after drill . What is left
> is a curl of copper protruding the hole. What we have observed and done so far:
> 
> -When it happens, it is on the whole job-maybe a 2 panel run, maybe a 100
> panel run.
> 
> -it occurs on multilayer and double sided panels.
> 
> -it happens on .5 ounce through 2 ounce foils.
> 
> -we have tried every combination of brushes.  320 grit works as well as
> anything else. (The deburr machine has 2 brushes top, 2 brushes bottom.  The
> operators are performing brush footprint checks several times a day.
> 
> -it appears to be on the top side of the panel as it is drilled. We have had
> our drill tool supplier in (inconclusive)and have emphasized the obvious to
> the drill operators-clean between panel stacks, make sure depth is correct, etc.
> 
> Any ideas?
> 
> thanks,
> 
> Lyle Anderson
> [log in to unmask]

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to:           *
* [log in to unmask] with <subject: unsubscribe> and no text.        *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact   *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask]      *
***************************************************************************