Drilling IC holes in a PCB

[Guest]

After many attempts to get a PCB to etch right, I finally succeeded, then I goofed when I tried to drill the holes for an IC, they were just a little too out of alignment Does anybody have any tricks that work for a guide or anything? I'm trying to drill on a set of fairly small pads (the classic PIC programmer found int uController section here, actually). Thanks!

 

[MP1]

I do not know of any alignment tricks other than using a magnifier so that the pads are easier to see when you drill them.
However, when you make a mistake like this, you can still use the hole. Just bend the leg a little and make sure you are not touching another pad. You might have to remove a little copper to insure there is not a connection where you do not want it.

MP

 

[Xenobius1]

Well first of all you must use a SMALL driller to it is easier to handle and ofcoarse a small drill.

The normal sizes are 0.8mm for normal components, 0.6mm for vias (jumpers) and 1mm for large componnets like voltage regulators, large rectifying diodes etc..

IF You use a 0.8mm drill and a small driller, if you aim right the drill will automatically find the hole and drill it ... (it bend a little) because the copper forming the pad will act as a guide.

 

[Guest]

Take a small nail,point of your geometry instruments and punch a small dot on the pad.
This will help for the tip of the drill to be balanced.

Have you heard about punchs used before drilling in metals?

 

[MP1]

This is why it is better to use a layout that shows the hole in the pad. There will be a little hole in the copper which makes drilling easier. On solid pads, the drill bits tend to walk before biting in.

MP

 

[Xenobius1]

Or else use a very high speed driller (30,000 RPM) like mine and it will drill the PCB instantly without running off before cutting. Drawbeck is that you must aim right or else it will drill were you do not want it

 

[InFLak]

I think buy a drilled circuit pattern. Put it on pcb, where you want to drill. Drill the PCB, from holes of drilled pattern.

 

[MP1]

Or else use a very high speed driller (30,000 RPM) like mine and it will drill the PCB instantly without running off before cutting. Drawbeck is that you must aim right or else it will drill were you do not want it

My drill is also 30,000 RPM and I have noticed that if the bits are new then it is how you have described. But if you plan on using them a number of times, you will get the walking problem. Even on my CNC I see this problem. Only the walking causes the bit to break. Besides, you are dulling your bits faster by drilling through a copper pad. A simple scratch of the etch resist will allow the etchant to make your center hole. Why waste bits?

MP

 

[Kasamiko]

I used a small precision screwdriver grind its tip to needle point and used it as center punch.. ;D