How to Cut a Straight Line Using a Skill Saw or Jig Saw

Intro: How to Cut a Straight Line Using a Skill Saw or Jig Saw

This instructable will teach you how you can cut straight lines using an electric skill saw, circular saw or jig saw. This is very handy when cutting long boards like a piece of ply wood. The ideal thing to use would be a table saw, but like me, some people can't afford one.

STEP 1: What You Will Need

The things you will need to do this are: - a pencil - to mark your cut line. - a square- to assist in making a straight pencil mark. - a straight piece of wood- this is to act as your saws guide so it should be free of big bumps or warping. - 2 clamps- these need to be able to tighten as they will hold your guide. If they move your cut won't be straight. - a measuring tape- to set your guide in the proper place. -of course you'll need a saw and a board you want to cut.

STEP 2: Measure Your Blade to Shoe Distance

Measure the distance from your blade to to edge of your saws shoe. The shoe is the bottom piece of metal that rests on you wood when cutting. measure the shorter side of your saw for a smaller more manageable measurement. Look at the photo above to see what this measurement should look like looks like.

STEP 3: Put the Guide Onto Your Lumber

Draw the line onto your board where you would like to make your cut. This line really only needs to be on the first and last 6 inches of your wood but I like it all the way across as a visual guide. Put your guide onto the wood your going to cut and get your clamps ready. Measure from your pencil line the same distance you measured on your saw and make a pencil mark. Do this to both sides then clamp your guide onto these marks. Measure again and adjust till its as perfect as you want. I like to get my saw ready as if I'm going to start the cut and make sure the blade lines up with my line when the saws she edge is against the guide.

STEP 4: Cut Your Wood

Now start your cut. While cutting keep the saws shoe against your guide and you will have a nice straight cut. Cut slow and steady don't force the saw forward. Wear the proper safety equipment and blah blah blah.

Comments

[Oberrw]

You do know that in Step 2, your measurement suffers from 2 problems that MIGHT create inaccuracies? Both problem stem from the fact that the picture shows the tape butted up against the plate of the saw blade.
1. This ignores the kerf of the saw cut introduced by the set of the teeth of the saw.
2. Most people ignore the inaccuracies of the hook at the end of a steel tap measure. Check your tape measure, you will see it only loosely attached to the blade of the tape. That is to allow for space it takes up when doing an inside measurement. The question everyone needs to check to see if the tape measures the same whether butting the end of the tape measure to an inside corner or stretching it over the outside corner of the edge of the piece of wood that is being measured. Theoretically, you can SOMETIMES compensate for the space by bending the hook either a little bit more or less.

Now, I know some people are going to say this is picking insignificant nits. But think about it, would you trust your life to a boat built where every measurement can be off by as much as 1/8”, creating that big of a gap between pieces of the hull that are supposed tto keep the water out and you afloatt?

[Fred Sculla]

A third problem is I never saw a piece of wood with a really straight edge for guiding. All my attempts resulted in the jigsaw shoe following the edge of the guide wood perfectly and thus missing the straight line sooner or later.

[mbecks]

You guys are correct. This isn’t perfect but I did seem to help a lot of people cut some scrap wood. Thank you for your in-sites.

[mbecks]

I wasn’t years ago but I now am. I encourage you to add to the instructable community and make an instructable on the topic. Thanks for checking out my instructable.

[BillyM94]

Hey thanks for the tips I'm going to go give it a try right now my ripsaw Marines went out of it and I have one ordered won't be here till Friday and I have a bunch of wood I got to get cutting out of here so the more I can cut better off I am I appreciate it I hope someday I can put something on here and help somebody

[vinay.lad.376]

I TRIED THE WAYS EVEN BOUT ANUTHER JIG SAW NO GOOD AND EASY RESULTS.IN FACT BAND SAW BULDING ILOST THE PLY OF 11100 X 100 MM BOARD.. IWILL HAVE TO THINK MYSELF TO SOLVE THE PEOBLEM .ANY BETTER ADVICE?PLEASE WRITE OT boson2001@rediffmail. com HURRY UP.

[mbecks]

Although this will help you cut straiter with a jig saw it isn’t ideal. A jig saw is designed for its blade to move around somewhat freely. You’ll be very unlikely to get a perfectly strait line with a jig saw. What project are you working on or what are you trying to build?

[mbecks]

You shouldn't have to pay to upload images here. I know I've never had to.

[Nikiniku]

I deleted my third posting after finding that my "breakthrough" method was not as good as I thought it was. However, I'll keep trying, so your comments give me hope. It's just that when I tried to upload my photos, I saw some comments to the effect that illustrations could not be uploaded without some kind of paid membership. Thanks to you, the next time I see those words, I'll check further.

[mbecks]

Glad you enjoyed it hope it works well for you. It's a little tougher to keep strait with a jig saw but still very doable

[Aimitis]

Thanks for the guide. It was well done and easy to follow even for a novice like me. I am just getting started, and trying to space my purchases. This was the first link when I searched how to cut a straight line with a jig saw since I didn't want to have to buy a circular saw yet as well.

[mbecks]

Your welcome. Made wood working way easier for me

[Gusgonnet]

nice, thank you!

[TDolce]

Ok,....I'm missing something. I'm sure I will be criticized for such a dumb question. How are you making the pencil line at the beginning stage? If both long edges of a 5 ft. board are crooked already,..what am I using to make sure my measurement line is straight? In other words,....I need to cut 4 " off the long end of one side of the board. If I measure up 4" from along the edge of the board to make my pencil marks and subsequent line (connecting the dots) it will end up being as crooked as the edge that I'm using as my guide. That's what is throwing me.

[mbecks]

All you missing is the use of a square edge as seen in the very first image of this instructable. Use that to get your strait line instead of measuring from the crooked ends of your board. If all 4 edges of your board are crooked then use this instructable methods to make a strait edge on your board. Does that make sense?

[mbecks]

The very first image of step one shows the square tool.

[dimtick]

the way that you're cutting with the circular saw, you'll get an uneven cut. you've got the narrow part of the saw guide supported while the wide part is on the waste side. when you start the cut, the saw will be flat but as you got and the waste wood sags, the saw will lean and you wont get a square cut.
what I do is lay several 2x4's perpindicular to the cut line and lay the plywood on that. set the saw depth to be just a little deeper than the plywood and then cut. I also use some guides that i made rather than a board. the guides work well because the edge of the guide is the cut line so you place the guide on the save side of the plywood and align the edge with the line. that way the blade thickness will be to the waste side. the guides are really easy to make and i'm pretty sure there are instructables for some.
also always lay the plywood with the good side face down. all the tear out and rough edge will be on the top. I also recommend getting a plywood circular saw blade. has a lot more teeth and makes a much cleaner cut. well worth the 20 bucks and 10 minutes it takes to swap blades.

[MohsenS6]

Thank you, I appreciate if you can provide more explanation maybe with pictures related to the guides issue.

[bo88y]

I also like to get the material closer to the ground when making long cuts, as shown in your picture. Sometimes I use some low benches I made that are about knee-high. I find that being above the work puts me in a position of better control of the saw.

[mbecks]

Thanks for the comments. It brings up a question though, why do so many people search for an instructable on something they already know how to do