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I just spent about 20 minutes trying to cut through a PCB with a hacksaw. These things are really tough.

What is the correct tool to cut PCB material, and get a nice straight line?

I saw something about a guillotine, but can't find a vendor.

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Have you considered a Dremel tool? Or is it not a fine enough cut? –  morgellon Dec 21 '09 at 10:51
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I've used a Dremel tool before with very nice results. Be aware though that you'll generate a lot of heat, the cutting discs are fairly brittle and the Dremel is a hand tool, so very long cuts are likely to increase your chances of busting the disc. Also, as mentioned up top by @jluciani, this cutting process will produce a lot of glass fibre dust which you absolutely should not breathe in. A conventional dust mask probably won't cut it for protection either as the dust is extremely fine. –  Sketchy Fletchy Jan 5 '10 at 23:30
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Don't use tinsnips - crap goes everywhere and you ruin the edge of the board. –  tronixstuff Jun 17 '10 at 6:50

15 Answers 15

up vote 23 down vote accepted

The first thing I should mention is safety. You need to wear breathing protection since the dust created by cutting is very hazardous to breath. Safety glasses should always be worn. As Norm would say -- read and understand all the manufacturers instructions for your tools.

I use either a hacksaw, bandsaw or tin-snips. Since I primarily use the bandsaw for wood I only use it if the blade needs to changed anyways. After cutting 10 linear inches of FR4 the blade will be useless for wood. I hate changing bandsaw blades.

Hacksaw is what I usually use. I leave 50mils between board edges. I place copper no closer than 25mils to the edge. The hacksaw blade is apx 35mils wide. I use a magnifying visor. This is fine for prototypes.

Sometimes I snip the edges with tin-snips. A scroll-saw would be ideal. Quick change carbide blades. Also I have heard of people using shears.

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Tin snips work great for short cuts, but they sometimes seem to add a little flex to the board while they're working. I wouldn't trust them for anything > 1-2 inches, and preferably not when I cared about the boards on both sides. –  edebill Mar 9 '10 at 23:15
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I agree with that. Typically I use them to trim corners if I need to round a corner. Saves a lot of filing ;) –  jluciani Mar 11 '10 at 1:18
    
Hacksaw works well when you put the board in a vice. protect it with thin cardboard, and use the top of the vice as a guide for the line you want to cut (pad with a little cardboard if you're worried about blunting the blade on the vise. –  naught101 Jan 14 '13 at 9:25
    
@jluciani Can you please describe hacksaw that you use. A brand, model, etc would be nice. –  Chetan Bhargava Nov 15 '13 at 4:39

I don't know if this is the best way, but I usually score it multiple times with a heavy-duty knife (on both sides) and snap it by hand. Obviously this won't work for any non-straight cuts. The knife I use is similar to one of these Stanley knife

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Yep for straight edges this is the quickest, most accurate and more importantly the safest (no fibreglass dust) I find that a few scores then use a square edge and bang the ob is done. –  Justblair Dec 23 '09 at 22:26
    
I use this too, with a ruler. Not the best but works fine to me. –  Daniel Grillo Jul 8 '10 at 14:02
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This works especially well for perf boards. Score down the center of a row of holes, line the score line up with the edge of the table, and press down quickly on the overhanging piece. –  ford May 8 '11 at 18:39

I finally settled on a wet tile saw. Turns out that it's not much different than the PCB saws that many places use to cut PCBs. A cheap wet tile saw from Harbor Freight costs about $70 (I got mine for $45 on sale), plus another $12 for the blade. The blade cuts a little over 1/16th of an inch, and with the saw guides I can cut very accurately. I also purchased a foot switch so I can cut PCB batches pretty quickly.

The advantage of a wet saw is that the dust is hardly a problem - it's trapped in the water, so while you still should wear protective equipment, you won't end up with fiberglass dust everywhere.

Further it's a very nice, ground cut. Very smooth - it's no different than the edges that were routed or sawn at the PCB fab house. I usually use a fine sandpaper to break the edges (which are a bit 'sharp') afterwards if I think people are going to be handling the PCB a lot.

The water poses no problem to the PCB itself, and if you already mounted components, most are washable. If you need to use it immediately a quick blast with the air hose or canned air removes all the water.

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Is this one of those miniature circular saws, with a lid over a reservoir, if so I have one of these and may have to give it a go? –  Amos Jun 17 '10 at 10:58
    
That's a great idea! I've got a neighbor with a tile saw, I'll have to give it a try. What kind of blade do you use? –  Kevin Vermeer Jun 17 '10 at 20:47
    
@Amos - Cut away! Any blade meant for ceramic/glass tile will work very well for fiberglass PCBs. –  Adam Davis Jun 17 '10 at 22:33
    
@Reemrevnivek - I have a wet use blade suitable for ceramic tiles. It's a simple diamond wet saw blade. –  Adam Davis Jun 17 '10 at 22:34

Use a paper cutter!

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This is basically the same thing as a "guillotine" he mentioned. –  davr Dec 21 '09 at 16:54
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I haven't been able to get this working effectively on 1.6mm FR4, just a warning. –  Mr. Hedgehog Nov 7 '10 at 16:56
    
+1: LadyAda also mentions a papercutter, but has pictures of a couple of guillotine PCB shears in the $200 to $600 range. –  davidcary Nov 9 '12 at 2:49

I score it deeply with a Stanley knife on both sides and snap it, as well. A tungsten carbide tile cutter also works, but I prefer the Stanley knife. It blunts the blade very quickly, I resharpen mine with a diamond hone and can keep using the same blade indefinitely.

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You can get bi-metal blades, they tend to last longer. –  Brad Gilbert Mar 10 '10 at 15:06
    
You can get carbide scribing tools from eBay pretty cheap, use with a ruler of something to start a straight score mark. Also, score both sides. If you can them use a press to hold one, or both sides (with wood or something to prevent bare metal press scratching board) then that can reduce the 'splintering' either side of the score mark. –  Chris2048 Apr 30 '10 at 14:16

While many of these have already been addressed I'll put my 2 cents worth in as I have had some good and bad experiences with this problem.

All of the basic options like Hacksaw, coping saw, tinsnips and scoring with a knife work for small jobs they are not my favourite for larger scale runs.

If you are just blanking out a large sheet for etching/developing etc. then a PCB guillotine, as you stated, is good for quick, straight and accurate cuts. See http://www.getlofi.com/ How We Make Circuit Boards – Video November 5th, 2009 entry for good vids on DIY PCB manufacturing including how they cut boards down. Farnell carry PCB specific guillotines but they are frighteningly priced, further googlage to the effect of "PCB guillotine" might elicit cheaper results. If you want to try paper guillotines Officeworks or other stationary suppliers will carry them for ~$60AU but I cannot vouch for this method.

When I was working at a signshop and had small circuits to produce I would use a bandsaw for all my cuts (including straight cuts, takes practice or a jig or both). As stated by jluciani safety should always be considered first! Wear a good breathing mask and not just a cheap one, just don't bother if your not going to spend the money and get a proper mask! I say this from experience because I developed breathing problems when I worked in this environment and the company didn't look after my health, lesson: look after yourself. If you can smell the fibre glass then you are breathing it in!!! Use an extractor too, even if you can't get a fancy industrial one Gaffer tape the hose of a normal vacuum to the table and you will eliminate most dust. Small bandsaws are available from Bunnings warehouse and Total Tools Industrial in Australia and should be available worldwide from any good industrial tool suppliers.

I hope this helps :)

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Like thisismyrobot, I tend to use a very sharp blade and a straight edge to "score & snap" boards with straight edges. Generally when I'm doing a board at home, rectangular boards are fine.

If I'm doing a circular or odd shaped board for an enclosure, I'm usually sending it out anyway, at which point I have the board house do it for me.

As others have said, if you do anything (grinding, sawing) that generates dust, be damn careful, use breathing protection. Preferably do it outside in an open area.

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I use a big scissor (originally meant for metal sheets, I don't know the english name, see the picture)

enter image description here

that's perfect for the scope.

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Tin snips I think –  Jim Dec 21 '09 at 10:53

If you have access to one, a router table with a straight bit will do a great job. You can probably pick up a decent router and table used for a reasonable price (varies by location) and they don't take up much space. The table allows you to assure your boards are squared, and the router itself will allow you to make funky shapes if you wish.

IT's a bit more involved than, say, an Xacto knife or tin snips, which also work quite well, but the results are really great and very quick. If you plan on processing a lot of boards, it's worth the investment.

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Nice cordless dremel tool like the 300 works fantastic.

The various cut off wheels work great on lots of other hobby chores/cuts.

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I prefer a 'nibbler', at least for small jobs it's ideal. I don't know if they all have a square cutting bit, but mine does, and it's fairly easy to cut in a straight line just free-handing it. The downside is that it takes a swath about an 1/8" wide, but for many purposes this is not a problem. Just google 'nibbler tool'. I got mine at a local retailer (RS) ten years ago, it's held up well.

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How about a sharp hacksaw? That's what I've always used. (Although I'll admit that I wasn't aware that the dust was THAT toxic; I'll be more careful next time. )

I can cut a small chunk out of a 4x5" piece of protoboard (about 12" of cuts) in less than 5 minutes, and not working that hard! Are you trying to do a multilayer/thick copper board, or making a great many cuts?

The alternative is to specify a long row of via-size holes (perhaps supplementing with routed cuts) in your PCB, if you're having it manufactured. Just read up on your board house's rules, put some holes in a row, and you can snap the board with your hands. Leaves a ragged edge, but not that much worse than a hacksaw. That's how we do it at work, at least.

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I use a scroll saw for weird cuts on boards I create. It just depends on what design your going for. Sometimes just a box cutter and snapping it over a hard edge is all I need for straight cuts.

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Shears/guillotines seem under-represented among the answers. Farnell has some PCB shears, but they can be quite expensive.

Looking for lower-cost alternatives, I encountered a review by Brooke Clarke of the Enco 130-5700 12" bench-top plate shear.

I haven't tried one yet, but a shear would be a good alternative to cutting or sawing which produce noise/mess.

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I've always used 1.6mm copper clad but I have always been a bit dissapointed at the options available.

I have tried the following methods:

  • Utility Knife: Works but is labourious and hard to get accurate results.
  • Paper Guillotine: Don't even bother unless you're using a very thin PCB.
  • Tile Saw: Excellent results but the noise and mess just aren't worth it.

I've had some excellent results using a metal shear, which are about a third of the price of the cheapest PCB shear I have found.

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Dead link (domain expired) –  JYelton Dec 11 '12 at 16:11
    
I have pointed it to the original video instead –  Mr. Hedgehog Dec 11 '12 at 21:34
    
Nice; that looks very similar to the Enco unit I found (and mentioned in my addition). –  JYelton Dec 11 '12 at 21:49

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