PCB cutter

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Most any decent woodworking tool (router, table saw, jig saw, etc) will do a decent job, especially with carbide-tipped bits or blades.

BUT . . . the the dust and fibers from the fiberglass are a health hazard! At the minimum, you need a breathing mask! A vacuum to suck the dust and chips away from you is also a good idea.

I much prefer to use a sheet metal shear, though I have to make arrangements with a friend to use it. I have also had good results on 0.062" (and thinner) material with an old-fashioned office paper cutter - the kind with a flat bed and a guillotine-like steel shearing blade pivoted on one end. I put a length of duct tape along the cutting line, on both sides, to minimize chipping and breakout along the edge. Don't try to trim off small strips of material - you need to have at least an inch or two on both sides of the cutting line or the material will tend to tear and fracture rather than shear cleanly.

Dale
 
I have used a shear type tile (floor tile-not ceramic) cutter.

I only need to clean up about 0.020" of shredded board edge.

It pulls slightly and you have to really hold the pcb down to minimize the pull.

Then I use a stationary sander to get the board edge to where I want it.

Yes, don't breath the dust.

I have also used a band saw. It cuts about 0.050" so I place two 0.010" lines on the "text" layer at 0.050" centres.

Since the blade will cut half of each line, this gives a very good line to cut to. If you keep the blade cutting each of the lines the edge will be within 0.005" of where it should be.
 
You can cut PCB with a heavy duty hobby knife, one of the kind with a snap-off blade about 3/4 of an inch-wide.

It needs accurate use of the knife. You score the PCB deeply both sides using a steel rule as a guide. You have to apply a lot of pressure to get a deep mark, then you snap the sheet across a sharp table edge, a melamine surface with a sharp right-angle corner is good. You have to be very careful when scoring the board, because of the large amount of force you are applying with your hands, make sure you do not cut towards any part of your body.

Of course you can only cut straight lines across the full width of the sheet, but you can cut any rectangle required except very small ones in the absence of any other tools.

Hold the sheet down with the heel of one hand with the scored line barely over the table edge and lean hard on it. Strike the free edge squarely in its approximate centre of leverage with the heel of your other hand with as much strength and speed as you can muster. You could trap the board in a large vice if a suitable one is available, but take care that the jaws do not mar the copper surface..

The technique works best when the score lines are exactly superimposed.

I use this technique to precut single or doublesided copper clad board before etching. It works for uncoated or resist-coated board with the protective black covering in pace.

It's easiest to do using the compressed impregnated paper type of board, but it's possible to do it with 1.6mm FR4, and you can cut board accurately enough to make doublesided boards with good alignment without any supplementary reference marks.

There's no problem with dust or tearing.
 
I use a hobby cutter ( about 3/4 inch blade width ) . I think this is also called a box cutter or NT cutter ?
The blade edge gets blunt pretty fast. For a more effective cut I first score the pcb from one side and then score it again from the other side. It breaks off real easy and then you can sand/emery it to get a smooth edge. You need to make the grove a bit deep, not just score a line !
Another thing I have tried is to grind the tip of the blade so that it become flat ( not the usual V edge) and is also curved inwards. That cuts a wide groove in the board and is much easier to break off. The ground edge does not last long !
I'll try to put up a sketch of the ground blade.
 
I use a heavy old paper cutter . . .
I think the ones that really work well as shears for PCB material were outlawed by OSHA about 15 or 20 years ago but you occasionally see them in flea markets.
There's also an import 12" combo sheet metal shear/brake/roller you can get that does a super job, plus it's good for chassis work.
If that tool does even a mediocre job at all those tasks it sounds like a good thing to have in a home shop. Who makes it?

Dale
 
A friend of mine bought one of those 12 inch guillotine style cutters. All metal and very heavy. It was very expensive ($300 I think), and it's hard to align the board properly; the machine itself gets in the way of the best line of sight view, if that makes sense. You end up guessing how to align the board... I'm going to try the vinyl floor cutter blade technique.
 
Yes, they're heavy! It has a rear stop like any sheet metal shear. You stick a ruler in and align the stop for the distance you want. The piece you keep is the one in back. Obviously it's harder if you just want to trim off a small amount as you do that in the usual fashion from the front. The nice thing about this kind of shear is that the blade angle is low, so the board doesn't shift as much during the cut as a heavy paper cutter. I always shear or score and break, as I don't want the Fiberglas dust around. It's nasty stuff.
 
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