drilling pcbs

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I use a Dremel, free hand. I havent broken any bits so far. Using a press is way too time consuming and also highly error prone if you dont have good 3-d vision! The most important thing here is to use the "keep drill holes open" in the layout printing software. Its far better than trying to center-punch a zillion pads.

I use HSS bits, which I sharpen every 25 holes or so. Use a magnifying glass and a fine stone. The angles have to be precise or else tear outs will occur.

Elektor carried a project for an NC drill press with a couple of steppers. Sounded nice but complicated.

I use Orcad for layout, print out on my Epson printer on photo paper, photolith, and use a negative photo-resist. It works nicely, most of the time. 2-sided PCBs (without vias) are easily produced.

vkj
 
I use a Dremel, free hand. I havent broken any bits so far. Using a press is way too time consuming and also highly error prone if you dont have good 3-d vision!

It's quick and easy if you adjust the drill press so that the resting drill bit height is just above the board.

The most important thing here is to use the "keep drill holes open" in the layout printing software. Its far better than trying to center-punch a zillion pads.

Yes!

I use HSS bits, which I sharpen every 25 holes or so. Use a magnifying glass and a fine stone. The angles have to be precise or else tear outs will occur.

HSS (high speed steel) bits explain why you haven't broken any. But there goes your argument about a drill press being way too time-consuming! With a carbide bit and a drill press, I could drill a hole every one or two seconds for an hour, without stopping. Besides, I could never find the HSS bits in small-enough diameters, whereas the carbide bits come in all of the sizes needed, and have 1/8-inch shanks.

Elektor carried a project for an NC drill press with a couple of steppers. Sounded nice but complicated.

I use Orcad for layout, print out on my Epson printer on photo paper, photolith, and use a negative photo-resist. It works nicely, most of the time. 2-sided PCBs (without vias) are easily produced.

vkj
 
It's quick and easy if you adjust the drill press so that the resting drill bit height is just above the board.



Yes!



HSS (high speed steel) bits explain why you haven't broken any. But there goes your argument about a drill press being way too time-consuming! With a carbide bit and a drill press, I could drill a hole every one or two seconds for an hour, without stopping. Besides, I could never find the HSS bits in small-enough diameters, whereas the carbide bits come in all of the sizes needed, and have 1/8-inch shanks.

Actually, I have about 8-10 of them all honed up and ready. Drilling is just in and out, almost instantaneous, esp for a phenolic board. After about 20 holes or so, you can see/feel the edges of the hole getting burred, its time for a bit change. Going by Digikey prices of carbide bits, (Carbide is unavailable in India), I cant justify carbide vs. HSS, esp. if you consider potential breakages. Besides you cant sharpen carbide unless you have a hard-to-find and expensive diamond hone. And even then its not easy. I know -- I've tried to sharpen carbide router bits, its quite difficult to get back the factory edge.

vkj.
 
Actually, I have about 8-10 of them all honed up and ready. Drilling is just in and out, almost instantaneous, esp for a phenolic board. After about 20 holes or so, you can see/feel the edges of the hole getting burred, its time for a bit change. Going by Digikey prices of carbide bits, (Carbide is unavailable in India), I cant justify carbide vs. HSS, esp. if you consider potential breakages. Besides you cant sharpen carbide unless you have a hard-to-find and expensive diamond hone. And even then its not easy. I know -- I've tried to sharpen carbide router bits, its quite difficult to get back the factory edge.

vkj.
I don't think you can sharpen carbides with diamond tooling. Try cubic boron nitride.
 
I don't think you can sharpen carbides with diamond tooling. Try cubic boron nitride.

I have tried it with this:
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it worked but the carbide bits break almost right at the shank so there's almost no twist left in them. I just buy some more from epay instead. With my new rebuilt press, I haven't broken a bit (expect once when I hit it while moving the PCB). Drilling is still as fast as doing it freehand except the holes are more perpendicular to the plane. :D
 
Actually, I have about 8-10 of them all honed up and ready. Drilling is just in and out, almost instantaneous, esp for a phenolic board. After about 20 holes or so, you can see/feel the edges of the hole getting burred, its time for a bit change. Going by Digikey prices of carbide bits, (Carbide is unavailable in India), I cant justify carbide vs. HSS, esp. if you consider potential breakages. Besides you cant sharpen carbide unless you have a hard-to-find and expensive diamond hone. And even then its not easy. I know -- I've tried to sharpen carbide router bits, its quite difficult to get back the factory edge.

vkj.

I never bought new carbide bits. It's been at least five years ago but I always got used boxes of 50 carbide pcb-drill bits for about $20-$30 per box. And after I started using a spring to keep my cheap drill press under tension, I almost never broke a bit. They never got noticeably duller, either, so I never had to think about sharpening them.
 
To use a drill properly and accurately on a pcb, you will need a table pcb. Now that is expensive and takes quite a lot of space.

I use a different tool, which I don't the name from, which came with my first PCB kit I bought 30 years ago in Brazil.

It looks like a desk hand clippling tool, and it has a pin that makes a hole in the pcb when you press the tool, if you know what I mean. This tool is very cheap and probably available everywhere.

It's very quick and accurate. The only problem is the pcb can't have any parts soldered in. In that case you will need a drill.
 
To use a drill properly and accurately on a pcb, you will need a table pcb. Now that is expensive and takes quite a lot of space.

I use a different tool, which I don't the name from, which came with my first PCB kit I bought 30 years ago in Brazil.

It looks like a desk hand clippling tool, and it has a pin that makes a hole in the pcb when you press the tool, if you know what I mean. This tool is very cheap and probably available everywhere.

It's very quick and accurate. The only problem is the pcb can't have any parts soldered in. In that case you will need a drill.

Is this some kind of a punch? If so dont you get a tear-out at the other side?

As to drilling accurately, as far as I know there are two approaches: (a) center punch first and drill. This is the most common, and the accuracy simply depends on how accurate your punching was. An alternate, accurate way is to use the "keep drill holes open" option in the layout software. No need of center punching, just use the guide hole on the copper. If your bit is true you will get the hole exactly at where the center was. (b) Dont center punch, instead, accurately align your job to the drill bit. A milling-machine type table is required. Highest accuracy is possible, but takes a lot of time to align. BEsides if the drill isnt sharp, it can wander. Requires some skill.

If you center punch AND try to align the job with a table any discrepancy between the two will result in the bit bending and possible breakage, not to mention angled holes.

vkj
 
I never bought new carbide bits. It's been at least five years ago but I always got used boxes of 50 carbide pcb-drill bits for about $20-$30 per box. And after I started using a spring to keep my cheap drill press under tension, I almost never broke a bit. They never got noticeably duller, either, so I never had to think about sharpening them.

Same for me. I bought multi-packs of resharpened carbide bits off fleabay and they should be good for thousands of holes... they were cheap enough and last long enough there is no need to think about resharpening them. I've broken more carbide bits by accidentally dropping or knocking them off my workbench onto the concrete floor than drilling anything.

I can't imagine it being possible to drill as fast by hand though it helps to have the press table up so the work is near eye level (wearing eye protection) and to have a strong light shining on it but not reflecting towards your eyes.

I toyed with the idea of adding a laser sight to my press like some of the newer model drill presses have but decided it wasn't really needed.

There are some cheap drill presses that just don't have the tolerance to do it though, if there is too much runout or vibration I would return it for exchange or refund if buying one new for this purpose.
 
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Is this some kind of a punch? If so dont you get a tear-out at the other side?

Yes, I think it may be called a punch.

It's very small, as I said, like a paper clipper.

No, I never got a tear out on the other side. It was always very clean, and I never replaced the pin, which probably would need to by now. Even if I don't know you can replace it on this tool, probably just get a new tool.

It's fast, clean and accurate.
 
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