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I attempted to test-cut a straight line using my new electric jigsaw. Therefore, I clamped a piece of scrap wood and used another piece as guide, marked the cut lines using a pencil and fitted the jigsaw with the blade and cut.

But my cut is like this:

Final result on jigsaw cut

As you can see, my cut is not straight and has some kind of stair-like pattern, so do you think that this blade used to cut is at fault?

Jigsaw blade

Would you recommend this blade for cutting straight lines?

Blade for recommendation

  • 7
    AFIK a narrow blade reciprocating saw cannot be used to make a straight finish cut. Generally a circular saw is used. – Jim Stewart Jul 19 at 20:27
  • you can make a jigsaw jig for straight cross cuts, lots of videos about that. I once made one to cut quarter-round at a perfect 45, and as long as I managed to slide in the trim in the correct rotation (which I did ~2/3 times) it worked great. – dandavis Jul 20 at 9:29
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    Is this a pure jigsaw, or is it a scroll-saw? If the latter, then maybe the blade isn't pointing straight forward. – Mike Brockington Jul 20 at 15:19
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    You likely pushed the saw too hard forward, and maybe didn't maintain steady enough pressure downward and against the guide. – Hot Licks Jul 20 at 17:39
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    For a straight cut on a board like that, you would have been better off with a hand saw ;) It just looks like you pushed it way to hard. – Chris Schaller Jul 20 at 23:56
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Jig saws are designed for cutting curves.

You can cut straight lines and generally you followed the correct procedure - using a straight edge. Your picture of the cut is pretty blurry, so it's hard to tell for sure, but there are several possibilities:

  • The piece of wood you used as a straight edge isn't as straight as you thought. Usually one uses a metal or plastic straight edge - one that is manufactured to be straight. Either a ruler, a level, or a specifically designed cutting straight edge.

    • If you're starting in with tools, wood working and house projects, get yourself a level and plan to clamp it carefully to use as a straight edge.
    • Depending on the design of the level, this might be easy or difficult. Purchase one with the thought of clamping as a straight edge to get more than one use out of your tool.
  • You didn't follow the straight edge as carefully as you thought you did.

    • Note my initial comment that jig saws are designed for cutting curves. That means that the slightest variation from dead straight will end up with a wavy line.
    • You have to have a thick enough straight edge, clamped well enough, that you can actually continually pull the base-plate of the jig saw against the straight edge. If you don't, it will tend to wander off because that's what they're designed to do.
  • It does appear that your blade has a lower tooth-per-inch count. I'd guess it's between 6 and 9 teeth per inch.

    • These blades are good for "general purpose" cutting and especially for fast cutting. They generally do not make a "pretty" cut. They generally leave a pretty ragged cut edge behind.
    • If you want a smoother cut, a higher tooth-per-inch blade is what you want. Something that has 12 or more teeth per inch. Be aware, however, that these will cut slower, and are often designed for cutting metal. They will cut wood just fine, but they will cut slowly in comparison to the faster cutting wood blades.

Once you get some practice with the saw, you will get to be pretty good a following your pencil line free-hand (without a straight edge), but it's not likely that you'll ever generate dead-straight lines with a jig saw (especially not free-hand). It's just the wrong tool for the job.

Some additional thoughts:

Jig saws are used for curved cuts, but also for notching or stopped cuts where you need to cut into a board, but not all the way through from one edge to the other. You use it to cut straight in from the outside edge of the wood, straight to the corner, then you nibble away at the turn until you've got enough clearance to make a 90° (or whatever is called for) turn, then make the next straight cut. Continue this for as many interior corners as you need.

None of this is to say that you

  1. Can't make straight cuts with a jig-saw (everyone has agreed that it's possible, but it takes practice and it's very unlikely they'll ever be laser straight), or
  2. Can't use it for making full edge-to-edge cuts. Generally, though, a through cut is made with a circular saw because that's what they are designed for.

Since you've already purchased the jig saw (and may not be able to return it for refund), go ahead and use it. Make some practice cuts to get the hang of how to use it and accept that your cuts will likely never be perfectly straight. If you do need a really neat final cut, adjust your cut to give yourself a smidge (1mm or so) of room to manually clean up the cut using a different technique as noted in Joe's excellent answer.

Finally, it looks like your "option" blade is labeled "extra clean cut". That will help make a nicer cut, but what you really want is a wider blade - one that has more distance between the points of the teeth and the smooth non-cutting side of the blade. This width is what will help the blade track straighter, though it still isn't the magic bullet for straights cuts.

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  • 8
    If you're riding the edge of the jig saw base up the side of your level and cutting into it, you should probably step away from power tools before you dismember yourself. A flat ruler, maybe, but not a level... – FreeMan Jul 20 at 10:51
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    @FreeMan Sure, of course, but OP's image looks like the cut was made in the dark by a drunk. The cut could be 99% improved with just technique. It could probably be 99.4% improved with technique plus a different blade. At this point in the game, OP really just needs to focus on technique, I think. – J... Jul 20 at 16:17
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    I'd also say the blade was forced into the wood, deflecting the blade off the cut, which can easily happen with a small blade like that. If you let the tool do the work and just put enough pressure on it to keep it moving forward without risking kickback, then the operator will get a much straighter and cleaner cut. This works with nearly every tool, and can take a lot of practice to get right. – computercarguy Jul 20 at 16:27
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    @Brad if the OP is struggling to make a straight cut with a jig saw (see note above describing it as "cut by a drunk in the dark"), it's unlikely he will be able to "rip a piece of plywood" with any great precision. As I noted, I've used a level before. I can trust it because I've tested it against other levels and other straight edges - it came out of the experience the same way it went in. I've got an over abundance of tools and wouldn't likely ever use a level again for this, but if you're just starting and on a tight budget, it's doable with care. – FreeMan Jul 20 at 18:35
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    @Brad Bending a level with a clamp is bad if you have a good level with high precision and generally high workmanship standards. I think looking at OP's results, they could raise their game tenfold even using a bent level badly over whatever it was they tried to do in the first place. I'm sure OP isn't spending hundreds on a good level - if they wreck a $5 level getting their technique level up, I think that's a fair sacrifice and a small price for a good lesson. By the time they're good enough to realize they need a better level it won't matter anyway. You always wreck a few tools learning... – J... Jul 20 at 18:59
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As a novice-level wood cutter, I will say that what helped me the most with learning how to make straight cuts using a jigsaw was to slow down. You can certainly cut in a straight line, without a guide, if you take it slow, with some practice. More pressure against the blade equals more likelihood of not being straight - let the blade do the cutting, not your force on the wood into the blade. That's an easy mistake to make, especially if you're used to hand-saws.

As others note, it's not entirely intended for straight line cuts - that's what the circular saw is for, and I highly recommend a good one - but it's possible, especially with thinner wood. That wood isn't too thick, so it should be doable with practice. A circular saw will be much easier to do this type of cut with, though. I made a straight cut my second attempt with a circular saw, while with a jigsaw it took five or six tries, and was never quite as perfect.

Also become familiar with the tools of "cleaning up" after your cuts - shaving a little bit extra off using a hand plane, using a chisel for little bits, etc. - so you don't have to be perfect! And as FreeMan points out, there's also sandpaper, or my preference a file, which may be easier on these end grain cuts if you're not too far off.

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    Excellent points! Wish I'd thought to include these in my answer. Also, sand paper will work for cleaning up a slightly ragged cut and is much easier to use on the end grain of a cross cut like the OP posted. It's much harder to plane or chisel end grain, especially for a novice. – FreeMan Jul 20 at 14:22
  • For sure, though I will say for me at least sandpaper is ... intimidating, in a way, because when it looks like that much wood as OP's picture does it feels like it'll take an hour to clean up with sandpaper! I know it doesn't actually, and especially if you use a file first before using paper, but it feels that way (sort of like a kid looking at a messy room and thinking "this will take forever"). – Joe Jul 20 at 14:25
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    Again, a valid point. If it's that bad, make a better cut then clean it up from there. ;) – FreeMan Jul 20 at 14:31
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    If you use Painter's tape to tape over where you're trying to cut, it reduces the splinters by a significant amount. It helps a lot at the edge. – Nelson Jul 21 at 4:03
  • Even better than @Nelson's suggestion is a scrap piece of board on top to reduce splintering. This only really works with a fence though, not cutting to a marked line (unless you mark the scrap board) – Chris H Jul 21 at 17:49
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Forget the guide block. Seriously.

Jigsaw blades wander for a variety of reasons, and all of them will cause you to have a non-square cut, even if you have a square guide block.

Instead, practice cutting to a line. (Or more accurately, cut most of the line on the waste side.) If the 'top' of the board is supposed to be the nice side, then mark the line on the bottom. (Or get used to cutting upside down, which takes even more time/effort...)

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  • 2
    It's very true that a jig saw blade will follow the grain. Not so much on a cross cut, though, and with a guide, you should be able to get reasonably straight. Don't think I've ever tried using a guide with a jig saw, though. Usually a jig saw cut is short and/or curved, so it's free-hand either way. – FreeMan Jul 20 at 0:48
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    This is exactly my experience. Just want to add something to the "cutting upside down" part: This is what helped me get the cleanest and straightest cuts. The dust will fall to the bottom of the wood and won't obscure your view of the line and the blade. Alternatively, using a dust collector can be used for the same purpose. – anderas Jul 20 at 8:06
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    @anderas Some jig saws have a blower that will blow the dust away from the cut line so you can see it (some are switchable - I can't fathom why someone would want to turn this feature off!). Failing that, each jig-saw operator is provided with a built-in dust blower (for years, I used this one). Trying to cut with the tool upside down and on the bottom of the wood just so the dust falls away (and into your face/eyes) seems like a horribly bad idea - dust in your face, even more difficult to follow the line, and the slightest slip means the saw is falling on you. – FreeMan Jul 20 at 14:20
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    @FreeMan I haven't seen that many jigsaws with builtin dust blowers, but mine has an option to fit a tube-like thing behind the blade which can be attached to a vacuum - basically the opposite of a dust blower. The upside-down part was about holding the saw below the wood while looking at it from above. (I completely agree that looking at the saw from below would be stupid.) In this case, you only see the blade and the marked line, and all dust is pulled away from you by the blade itself and gravity. The downside (no pun intended) is that it ony works comfortably if the wood isn't too big. – anderas Jul 21 at 6:18
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    @anderas wow... you hold the saw under the wood, following a line on top of the wood, with the point of the blade jabbing up and down at you with nothing but air between you and the blade? You're a braver man than I! Frankly, that sounds like the kind of thing I would do only if I desperately needed to cut a piece of wood already installed into something with no way to remove it and no way to get the cutting tool on top of the wood, and a really bad recommendation to make to someone who is brand new with power tools. – FreeMan Jul 21 at 10:51
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A jigsaw isn't designed to make perfect cuts. Straight cuts can be made but the stock has to be clamped down and the fence, guide block, must be clamped down too. You can't hold down a guide block with one hand and operate the saw with the other, the guide block will move and the saw will jump, as is obvious from your pictures. Clamp everything and use both hands on the saw, practice makes perfect.

Use the proper blades for crosscut or rip cutting. The type of blade is labeled on the packaging.

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A jigsaw is fully capable of making a decent cut. Will it be as nice as a table saw or as a pull saw? No. But the cut you have here doesn't appear to have any straight lines at all.

You want:

  • Downward pressure
  • High blade speed
  • Don't advance the blade into the wood faster than the blade wants to cut the wood

With those three things I don't think you even need a straight edge to get better results than that picture. A straight edge will help further though.

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    This is the perfect point, its not about simply slowing down, its about maintaining vertical pressure on the blade by not pushing the saw forward in a way that puts too much backward pressure on the blade, which causes it to warp. The material and type of blade will determine the max speed. But learn how to judge what that speed is. You'll find the point where it glides through the material, when it moves as you push it. You shouldn't be forcing or pulling it through the material. – Chris Schaller Jul 20 at 23:54
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Ever considered why it has its name? It's designed to do just about anything except cut in a straight line!

Its blade is thin, front to back, on purpose. So it can and will go round corners easily. To cut straight lines, the blade needs to be long, front to back, so it's difficult to turn. As in tenon saws, which even have a strengthener to stop them flexing, or handsaws, which have deep blades.

The hand jigsaw, sometimes a coping saw, has an even thinner blade, to get round corners even more easily. One of the reasons it has an adjustable angle handle.

To enable straight cuts, use any saw with a 'deep' blade, so when the front edge may start to wander, the back edge keeps it on the straight and narrow. Where we all belong..!

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  • It's name comes from "cutting using a jig" (en.wikipedia.org/wiki/Jig_%28tool%29). If you want a semi-circular cut, use a radial jig. If you want a straight cut, clamp a straight-edge down and use it as a jig. – Flydog57 Jul 20 at 23:41
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The blade looks bent. I've drawn lines along the spine of the blade as shown in the photo in the question. If we assume the background is flat, the point where my red lines cross isn't sitting on the surface, and is bent towards the camera. See also the shape of the shadow, and the non-round holes. On a non-flat background, it's possible the blade has been bent towards the teeth, but that would mean pressing very hard backwards without buckling it.

Bent jigsaw blade

Step 1: don't start with a bent blade, instead buy a new one. Bent blades are more likely to break and won't cut straight. If the blade bent during cutting, you were pushing too hard, and probably sideways.

When replacing it make sure the blade you get is compatible with your saw. I suspect those in your last picture aren't. There are two major fittings for handheld jigsaws, as well as larger reciprocating saws.

Mount the blade very carefully, ensuring it's straight and solid.

If you're cutting against a fence, as I often do for straight cuts, make sure the fence extends far enough beyond the workpiece that the sole plate can be lined up against it before you start to cut.


Here's the shape I think the bend has taken, mocked up in paper. From the less angular shape of the shadow I'd expect the bend to be a little smoother in the metal blade - but it would be as it's much stuffer and thicker. The location of the bend is where the support stops in my jigsaw, suggesting the blade was either bend before cutting, or the saw was pushed sideways rather hard during the cut (without keeping the soleplate flat to the wood) bent blade, mocked up in paper

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  • ooh... good catch on the blade mounts! I'm not seeing a bent blade, unless you're just speculating. – FreeMan Jul 22 at 11:22
  • @FreeMan see the comments under the Q - it's bent. I'll upload a marked up copy of the OP's picture in a moment – Chris H Jul 22 at 11:27
  • ah, I see the shadow. I was looking at the blade itself. It looks like it's manufactured with a "bend" causing the bottom of the blade to be forward of the top of the blade when properly inserted in the saw. I think I saw the shadow as it was sitting on an uneven surface - the shadow appears to be smoothly rounded toward the bottom of the pic, an odd bend for a blade that was bent during misuse, as opposed to the nice curve of fabric. Maybe OP can clarify the backdrop used for the picture – FreeMan Jul 22 at 11:30
  • @FreeMan I don't have a blade to waste, but I've mocked something up out of paper and added it to the answer – Chris H Jul 22 at 11:42
  • You may well be right! Nice mock up, BTW, though I'm disappointed you didn't use a real blade... :D – FreeMan Jul 22 at 11:57
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I quote from an online article concerning saws of all kinds.

  1. Jigsaw

A jigsaw is a handheld powered saw. It has a smaller blade and finer teeth than a reciprocating saw. It moves vertically. You can change the speed to make it go faster or slower. This saw is designed to cut curves and other non-straight lines. https://sawingjudge.com/different-types-of-saws/

This is a useful article to skim through from end to end. It is quite comprehensive.

Each type of saw is described briefly. If you think a particular saw is best for your purposes then it is a good idea to search online for a saw of that name.Very often YouTube will have a video showing how to use it. For example http://bitly.ws/96y6

In the case of a jigsaw you need to distinguish when searching between "jigsaw puzzle" and "jigsaw cutting".

Note that jigsaws are mainly used for cutting (curves) in sheet materials such as plywood. If you want a clean cross-cut (as hoped for in your photo) then try searching online for "cross-cut saw".

You don't have to buy every kind of saw going but it helps to read a little (and perhaps try searching for example for "general purpose saw" etc.).

To avoid a lot of initial expense, it is worth considering buying hand-saws. When they are new and their blades are sharp it is surprising how quickly they can cut. Take note of other answers. When using a drill or a saw, always let the tool do the work, it is rare that a lot of pressure is needed.

If you find yourself working hard, then you may have the wrong sort of blade but, more likely, the saw has become blunt with use.

Arnold Schwarzenegger could probably saw with a blunt blade and I've seen builders with big muscles labouring away with a rusty and blunt saw at a rough plank. They get there eventually.

Hand saws can be reset and sharpened but it's a skilled job. Quite frankly, these days its cheaper to buy a new saw than go to the trouble. For power saws, check the blade for signs of wear after use and consider replacing them if they are bent or damaged. It saves time and money in the end.

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  • Your quote is wrong in at least one respect: "You can change the speed to make it go faster or slower. " isn't universally true - mine doesn't, and if replacing it I wouldn't pay extra for variable speed. It's not needed when using the right blade and being gentle – Chris H Jul 22 at 12:17
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    You'd be hard-pressed to find a new jigsaw that's not variable speed. Even the cheapest toybox models have variable-speed triggers. It's a useful feature when you're trying to ease into a cut in soft material. – isherwood Jul 22 at 16:24

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