Thanks everyone for your advice and tips. I'm going to not drill the hole (at least not all the way through) and also not going to use the teflon sleeve approach - the patch is easier done from the topside - but all this is good to know. The fix will be to put a little epoxy over the hole to seal it (maybe drill it out a little so the epoxy "bump" isn't significant), bend lead out from under the LED package, and tack-solder the resistor using one of its leads as one of the jumpers. I did three boards this way (sans any drilling) and its straightforward. Thanks again everyone! J Win Wiencke wrote: >>Well I have 100 pcbs with an error on them, stupid oversight, but now I >>have to come up with a patch-em plan. Aaargh. > > > The drill must be sharp and both the rotation speed and feed speeds are > critical. > > We have had good luck using a diamond hone to flatten the tip relief > somewhat -- this makes the drill cut slower but seems to not "smear" the > copper on one layer into the other. > > Feed is best done with a weight on the control arm. You might need to give > it a push to get started but gravity can be your friend when you need > consistent results. That said, one guy here has such a deft touch that he > simply cranks the drill in by hand. > > Rotation speed is a dicey area. I just diddle until I get it right. > Sacrifice one board to cut up into test squares. Inevitably it is slower > than I expect. Start at the recommended production drill speed and work > down. > > Finally, we've used catheter tubing to insulate. One can even get it in > Teflon although the stuff tends to cold flow and have an annoyingly uneven > wall thickness. I heard of someone using lacquer but never tried that > myself. > > Good luck on the rework -- and welcome to the human condition... > > Win Wiencke > -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu