Introduction: Circular Saw Rip Guide--My Version

Picture of Circular Saw Rip Guide--My Version

Rip guides like this one can be found on YouTube and in other Instructables here. They are very handy for precise ripping of large panels and for trimming things like doors. I am including a couple of modifications, though, that I think readers will find very beneficial. One is a cost reduction. A second is no need for making a precise cut during the construction of this guide. Another is a way to clamp the guide so the clamps do not interfere with the motor housing on the saw. The fourth is two working edges in case one should be damaged.

In the photo you see my rip guide prepared to trim 1/8 inch from the bottom of a door. 

Step 1: Materials and Tools

Picture of Materials and Tools
  • 1 MDF trim board 3/4 x 3 1/2 x 96 inches 
  •  Tempered Masonite 3/16 x 15+ x 96 inches
  •  Bevel-headed wood or sheet metal screws: # 8 x 3/4 inch

  • Rule
  • Drill with bit and countersink
  • Screwdriver
  • Sawhorses 
Lowe's Home Improvement Stores in the USA sell painted MDF trim boards in various widths. These trim boards are very straight. Since the trim board will be mounted with screws to a piece of Masonite almost 15 inches wide after trimming, the piece of MDF does not need to be completely resistant to bending under lateral pressure. The Masonite will add sufficient rigidity.

Have the store rip 15 or 16 inches from the long side of a sheet of 4 x 8 feet Masonite. It does not matter if the cut is not completely straight, but the panel saw will likely yield a straight cut. (My saw's base is wider than some with almost exactly 5 inches between the edge of the base under the motor housing to the nearest side of the saw blade. If your saw's base is smaller, the Masonite could be narrower. But, the Masonite needs to be twice as wide as the base dimension on the motor side of the base plus the width of the trim board. Leave a little extra on both sides to be trimmed away.)

I had a car, not a truck, when I went to the store. I had the store cut the remainder of the Masonite so I had two pieces about 33 x 48 inches each. They may not go into a car trunk, but will slide through a rear car door and not rise above the seats to obstruct your rear view on the way home. (The panel saw at my store is poorly aligned and corners on crosscuts are not square. The operator has tried several times to get the management have the saw aligned again, but has been unsuccessful. Be aware.)

Plans for rip guides like this often suggest ripping about 6 or 8 inches from the long side of a sheet of 1/2 inch plywood. This is aligned along the edge of a sheet of Masonite. That means you may be buying both a sheet of plywood and a sheet of Masonite. One advantage to my version is that you buy a sheet of Masonite and a trim board only, which makes for a lower cost. (Also, if you are cutting the piece that will actually guide the saw, you will need a means of guaranteeing that cut is perfectly straight. That may not be possible in a beginner home workshop. The straight trim board will be a big advantage for getting a straight guide without a large table saw the beginner workshop may not have.)

Center the trim board on the long Masonite piece and clamp with "C" clamps. Support this sandwich with enough sawhorses to keep it from bowing. 

Step 2: Attach With Screws

Picture of Attach With Screws

I chose to have the saw base ride on the smooth surface of the Masonite. So, the rough surface will be down on the finished guide. Here you see the two pieces inverted for assembly. I measured so the screws would form a line down the center of the guide. A screw is installed about 1 to 2 inches from the end. Then I placed screws every 8 inches. The heads are countersunk so they do not scratch a finished surface in use.

Step 3: Trim the Excess From Both Sides

Picture of Trim the Excess From Both Sides

Once the Masonite has been attached to the trim board with screws, invert and support the assembly on enough sawhorses that it does not sag. 

I positioned the edge to be trimmed away off to one side so that the saw will not cut into the sawhorses and metal roller support shown. Make certain the cord is not restricted. With one smooth movement hold the saw base against the trim board and move the saw the length of the saw guide to trim away any excess.* Notice that I clamped the assembly to the sawhorses with "C" clamps so I did not need an assistant while cutting.

I loosened the clamps and turned the assembly end for end. Then I clamped it again as before and trimmed the second side. That gives me the advantage of two edges that mark the cut. If one is ever damaged, I still have another.

*My saw has no "run out" that I can determine. On some saws, especially lower-priced saws, the blade moves outward a tiny bit when the saw is powered up. Cutting in one smooth motion is to eliminate the effects of run out. I will use this guide most often on cuts much less than 8 feet long. I have decided to guard against any run out by starting the saw an inch or so away from the cut line and move the saw base toward the edge of the trim board as I move the saw forward to begin the cut. I will also move the saw away from the trim board before the blade stops spinning. 

Step 4: In Use

Picture of In Use

One of the frequent problems with clamping a straight edge for guiding a circular saw is that the "C" clamps obstruct the movement of the saw by colliding with the motor housing.* But, the Masonite on both sides of the trim board means I can clamp the rip guide by means of the Masonite on the side opposite of the saw cut, which is yet another advantage of my version. The "C" clamps are far out of the way, and the guide is securely clamped in place. (You can see a piece of 1 x 2 in the lower left of the photo. It is functioning as a cushion piece to protect the finished surface of the door so the clamp does not leave a mark. Also, the left rear corner of my saw's base is cut at a diagonal, which explains what you see in the photo.)

*If you watched the YouTube video linked in the Introduction, the author of that video cut the piece that guides the saw to be extra wide to allow his small saw to clear the clamps. Too much width increases the weight of these guides. The version I made weighs 14 pounds, but provides two working edges. You will need to make your own choice.

Step 5: Trim

Picture of Trim

Align the edge of the Masonite with the cut line. After the guide has been clamped in place, make certain the cord is out of the way. Start the saw and trim the excess from the panel or door.

Step 6: Finished Cut

Picture of Finished Cut

The photo shows the bottom of the door after it has been trimmed. Notice how neatly and smoothly the cut edge follows the edge of the Masonite.

Years ago I purchased a two piece aluminum saw guide for ripping. It deflects a little in the middle and I always had to buttress it from the side. Even then, it was not completely satisfactory. This guide from Masonite and an MDF trim board is so much better. When I need to cut something less than 8 feet in length, I just allow equal portions to hang over at the ends and it all works very well. 

I stand my rip guide against the wall when I am not using it. After a while it will begin to bow a little. That is not a big problem, but I can also turn it over periodically so the new position takes out the old bowing. After a while I will need to turn it again.

This guide is made to be used with my saw and the blade I currently have on it. A different saw or a different blade can introduce variables and should have their own custom constructed guide. Also, using this guide with a different saw could render it useless for my saw. If you lend your guide, lend your saw and blade, too.

I wish I had known about these rip guides years ago and had used one then instead of making do with improvised guides that often left "C" clamps in the way of the saw's motor housing. I am also glad I was able to make mine without buying two sheets of plywood.


jeffjenn (author)2017-07-24

I hang mine from a screw in the wall of my shop. Really helps keep it straight and flat.

Phil B (author)jeffjenn2017-07-25

That is a good idea. My shop has also usually been a garage with two cars parked in it, too. Any wall space has many things of various lengths standing against it or it has pegboard with hooks on it.

brian32768 made it! (author)2017-03-27

It took longer to read your article than to build and start using a quickie version of your guide.

I can't go to the store today so I built a small version using 1/4" hardboard from the back of a scrapped kitchen cabinet and a 4' scrap of MDF trim. Total cost $0.00. Time saved? Invaluable. Until now I have been using just a ruler and an MDF trim scrap. This works but takes at least 3x as long.

As soon as I can I will get a sheet of hardboard and do permanent 48" and 96" versions. Here is a photo of my scrap version. That Workmate was a $20 Craigslist find.

Thanks for the other person's suggestion of pointing the clamps down and putting the extension cord over my shoulder.

Phil B (author)brian327682017-03-27

Thank you for sharing what you made. A 4' version is very handy for many cuts. The 8' version becomes necessary if and when you must deal with a full sheet.

brian32768 (author)Phil B2017-03-28

I cut one narrow and one wide side figuring it would be more versatile. I found that using the narrow side allows the saw to rock up and down since most of the saw's base is unsupported. (That is, only the section between the blade and the edge of the base is supported by the guide). With care I can use it but when I do a new version I will make it wide on both sides. Or maybe I will use one side for my router as you suggested.

ryanjohnlenz (author)2016-06-17

Hi Phil--great instructable (and nice job replying quickly to everyone's comments!)

Two questions:

1.) I have a piece of aluminum angle "iron" (a 90 degree piece about 6' long). It appears to be very straight (that's why I bought it). Do you think this would be an adequate substitute for the MDF? It's 'faces' are about 1.5" tall.

2.) If I was going to use this guide to cut a 45 degree bevel (to make French cleats), would I need to modify the guide in any way, or just shift it further from the desired cut-line to account for the angle?

Phil B (author)ryanjohnlenz2016-06-17


I think your aluminum angle could work. It may flex sideways a little in use. I would still mount it to Masonite with screw bolts every few inches to eliminate the possibility of flexing for straighter cuts. That also allows the edge of the Masonite to define the cut line for easier setup. One reason I like the MDF is that it has a low profile and the saw motor can pass over it without obstruction. The higher profile of the aluminum angle will likely get in the way with many 90 degree cuts. A 45 degree cut for French cleats should not be a problem.

Qtronik made it! (author)2016-05-24

one side wide the other for the narrow.

Phil B (author)Qtronik2016-05-24

One of my objectives was to provide a wide enough space on the side without the saw to allow the saw motor to pass over the C clamps. That may or may not be possible with the arrangement shown. I expect you are making room for the wide part of the saw shoe and the narrow part, too. I think someone suggested one side could be a guide for a saw and the other for a router. Thank you.

KentM (author)2016-01-02

Excellent instructable. I used a metal guide for years and almost always had to clean up the cut edge on my table saw (never easy with a very long board). The more woodworking I do the more I appreciate the many jigs I've built that make the job easier and safer.

Phil B (author)KentM2016-01-02

Thank you for looking and for commenting. I hope you can use it. I do not use it often, but it has been handy when I needed it. I wish I had had one of these years ago.

ptindall (author)2015-10-13

This is a nice design and just what I was looking for. One limitation to be aware of - the 1x4 under the motor housing may not allow the saw to be set to it's maximum depth of cut. While this isn't a problem for most applications, it limits the depth of cut just enough that this jig won't work on a 1 3/4" wooden door, at least not with my saw. A thinner piece, such as 3/8" plywood would allow just enough clearance for my saw to make the cut. Nevertheless, this setup is super easy to make and super handy for most ripping applications, and I'm glad I made it. I wound up just using the edge of the Masonite base as the guide for trimming the door. Thanks for the nice design! I wish I'd had this guide years ago.

Phil B (author)ptindall2015-10-13

Saws do vary. The 3/4 inch 1 x 4 works fine at maximum depth with my saw. As shown, I was able to trim a door with my saw and a 3/4 inch guide strip. The usual design for one of these jigs involves fastening the machine cut edge of one sheet onto another sheet of material possibly of another thickness. That results in a cutting guide with cutting on one side, not two sides. In my experience the clamps pose an obstruction to the saw. With two cutting sides, one can be used for clamps and there is no obstruction to the saw motor. Your comment about wishing you had one of these years ago reminds me of some custom cars I have seen. The seats are so low to the floor that a person is too old to get in and out of them by the time he is old enough to afford one. Thank you for looking and for commenting. I would be interested in seeing a photo of the one you built.

Phil B (author)2015-09-29

Luella, I am sorry to hear about your friend's injury. Power saws can be dangerous. Learning about safety precautions is very important. I find it helpful to set the depth of cut to the minimum needed. People actually hold the wood from below with their fingers in the path of the saw blade. Keeping the depth of cut as shallow as possible means an injury from unsafe practice would make a flesh wound rather than cutting fingers off. Stand off to the side a little so you are not in the pathway if the saw kicks back. Make certain the blade guard works properly. Keep the power cord out of the way so you do not cut into it. Do not support the weight of the saw by the part that will be cut away and fall off. Do not let long hair hang down near the spinning blade, and keep loose clothing away from the saw. Do not set the saw down until the blade has stopped spinning. Unplug the saw when you are not using it, even between cuts.

I am having difficulty understanding why you were not able to use this successfully. Perhaps a friend with experience using one of these saws can help you master using this.

LuellaEHarkness (author)2015-09-26

I tried it, but it does not succeed, it is a difficult skill. My friend- Daphene, He even injured while using saw :'(

BerniceD2 (author)2015-07-28

Even if you have a table saw this is still an incredibly good idea to have. Generally speaking table saws are pretty useless for ripping down WHOLE sheet products unless you have some monster table. I'm going to use the table saw to get the 1x4 as straight as possible then attach it. I'm still more worried about making the piece on the underside square to the whole unit. If it's off even by a 1/16, because it's so small, over 4' that could be a big impact. Framing square might help.

Phil B (author)BerniceD22015-07-28

Just make the thin bottom piece larger than needed and rip it. No squaring is needed then, the straight edge of the 1 x 4 guide will make the edge of the thin piece parallel to the guide.

Use a string, preferably a chalk line to snap a straight line on the bottom piece. Use it as a guide when attaching the 1 x 4. That will make sure any error is very, very tiny.

I would be concerned that a 1 x 4 of real wood could warp a little with changes in humidity. Wood always does. That is part of why I used a composite. Those are very stable dimensionally.

Remember that the machine chit edge of a piece of plywood is very straight and true, and easily available.

feiwulfli (author)2014-09-26

Can I substitute masonite with another material?
What would you recommend to keep that straight edge?

Phil B (author)feiwulfli2015-04-29

I am sorry. Somehow I missed your inquiry. You could use Masonite. If you have a factory cut sheet, slice on four or so inches and use the factory cut edge as a guide. Make certain it is thick enough that the saw base does not ride up onto it, but stays alongside of it.

jmorg1980 (author)2015-04-29

Great Idea! I used some extra laminate flooring I had laying around because I like the surface on both sides and it was free. The straight edge goes right over the joint of two pieces. I made a 50" one with the intentions of making 2 and locking them together for 100" for storage purposes but I can tell that the locking system will take so much abuse it wont last. So I will be making and 8' one as well.

Thanks for the idea though saw it last night and said I have to have one.

Phil B (author)jmorg19802015-04-29

Thank you for looking and for commenting. Yours looks good. I think I mentinoned I bought a rip guide made from aluminum more than 30 years ago. It is in two pieces. One of the big flaws is keeping it straight and from moving at the joint when in use. You will like the 8 foot version.

jmorg1980 (author)Phil B2015-04-29

It is amazing how simple this is that I never thought of it before. I have always used a straight edge but have always just figured out where my marks needed to be to make up the difference for the saw. I guess it was never so cumbersome that it turned into a "there has got to be a better way" to make me think to much about it. This will save so much time and even more so a math mistake and a miscut. I almost feel like I own a track saw.

Phil B (author)jmorg19802015-04-29

You make me wish I had thought of the original idea rather than adapted it to make one inexpensively and to suit my needs better. It is almost a little like a track saw. It certainly does reduce the chance for error in how far to set off a rip guide. I hope you enjoy it for a long time to come.

ldenicola made it! (author)2014-07-09

REALLY wish I'd had this during my "trio of bookcases" construction 18 months ago, but I'm working on a long/low ottoman now and this is making shorter work of it!

Phil B (author)ldenicola2014-07-09

Thank you for the photo and for the comment. It looks good. I am glad it is working well for you.

mbecks (author)2014-05-06

I made an instructable for a similar thing, but seeing this you method seems much cleaner and less time consuming when done. Im sold on it and will build one soon. thanks

Phil B (author)mbecks2014-05-06

I hope you enjoy the one you make and it serves you well.

gnach (author)2013-12-11

Well done, Phil. I'm with the glue and screw camp. Tempered hardboard (masonite) is best for these guides. I use both edges of my saw and so I cut the guide from both edges. I've drilled small holes in the center strip to use brads when I can't get a clamp to reach. Oh, and I wouldn't trust neoprene not to move, my skil wormdrive is not forgiving.

Phil B (author)gnach2013-12-11

Someone made one of these guides to handle his saw on one side and his router on the other. Your idea of making a guide for both sides of the saw is good, too. I also like to be sure things will not move while I am using them.

Avasar10000 (author)2013-09-14

Hello Mr. B,
I know this question may be ridiculous and that I am very much so over thinking this jig construction. My dilemma is that I had purchased a brand new, factory….errr….”factory” milled 96” piece of red oak to be used as a straight edge. When I got home to use it as such, I discovered it was not straight. I have a limited workshop consisting of a table saw / router table combo (connected to a joint tech system), a circular saw, a scroll saw, a small drill press and a floor standing drill press (with lots of run-out). How do I obtain or create the straight edged board needed to build this jig with my tools? I am currently not a wood worker, but rather a tinkerer / aspiring jeweler who is in the process of building my Jeweler specific work bench from some very nice up-cycled Bocote and misc. other wood components. Thank you in advance for any advice.

PS- Your take on this jig is very interesting as compared to other similar jigs that I have seen elswhere. Once I feel that I can properly produce it...I plan on using it until both sides are worn out!!! - God Bless!!!

Phil B (author)Avasar100002013-09-14

It is a fundamental law of the universe that wood will always move and change with changes in humidity. I used a trim board made from a wood composite because it is not affected by changes in humidity. Then I mounted it on Masonite which is also a composite not affected by humidity. You could make a stable straight piece from your red oak, but it would be a tremendous amount of work. You would need to rip the oak into at least two narrower pieces and true them with your joiner. Then you would need to glue them back together with the tree rings flipped over in every second strip so tensions in one piece are cancelled by tensions in the neighboring piece. You would also need to clamp them in place so the assembly is straight when dry.

Avasar10000 (author)Phil B2013-09-14

Thank you Mr. B!

I appreciate your timely response. I believe it will be better for my current level of woodworking skills to simply use the red oak for another project and make a trip to one of the Big Box stores to pick up the prescribed materials. I did not discover this jig until after I had purchased the oak or I would have purchased the correct materials initially. Funnily enough, I too have the very same aluminum jig described in step 6. After I determined the oak was not straight enough I recalled that I had this "jig". I marked my $45 per sheet birch plywood and triple checked my measurements, then I clamped the jig down. I noticed that it did deflect in the center. So I placed weights all along the rail to hold all in place. It still did not give an accurate enough cut. At that point I referred to the web for more info on cutting straight using a circular saw. The birch plywood will not be a total waste as I can now build the jig in your Instructable and ultimately salvage the majority of the panels. I wish I had, had the foresight to check here first. Lesson learned….I hope.

God Bless!!!

Phil B (author)Avasar100002013-09-14

We have all had things that did not go right the first time. I misread your original post and thought you had a joiner. The red oak is too good to use as a saw guide. It will make a nice project for other rhings. Let us know how your rip guide works for you.

Moltroub (author)2013-01-18

Very good instructable Pastor Phil! I truly enjoy reading your efforts. For me, it's like having my father and uncles explaining things to me. Do you think the vinyl trim would be strong enough to be the guide or would it present too much bow to the Masonite?

Phil B (author)Moltroub2013-01-18

Thank you. I am glad you enjoy these things. I enjoy doing them. The trim board I used is not vinyl, but a composite material similar to MDF. It is available in greater widths, like a nominal 6 inches. That is wide enough to resist bowing. I hope that answers the question you are asking.

Horsehockey (author)2012-11-25

I use a piece of 1x4 longer than the piece to be cut. My Milwaukee saw is 5 1/2 inches beteen the inner surface of the blade and the outyer edge of the saw base. I mark the piece to be cut at the cut is to take place, measure another 5 1/2 inches back and clamp the 1/4 in place. Using metal spring clamps to secure the 1/4 in place allows the saw motor to clear the clamps.
Simple, fast, and cheap. I cut a lot of 1 1/2 styrofoam board (4x8 and 4x10 sheets) on the ground. A 2x4 under where the saw will run keeps the blade out of the dirt or grass and provides a rigid surface for the cut.
The saw guide dedpicted would be really useful in a cabinet shop but wouldn't last long in a construction site with the foremans whip on a workers back.

Phil B (author)Horsehockey2012-11-25

For the last 40 years I have often done what you describe. It always demanded more mental effort from me to be certain I was reading the measurements correctly and making them identical on both ends of the rip guide board. I always wanted something like this and find it much easier with more certain results. But, if you have something you like, go for it.

mikem360 (author)2012-11-08

i put 2mm neoprene type foam on the bottom, no longer need to clamp it in place

Phil B (author)mikem3602012-11-08

Thank you for the comment and the idea. I would not have guessed the neoprene foam would be dependable enough to guarantee no movement.

fjr_scoot (author)2012-11-05

NICE! Great ideas that I will implement the next time I make one of these

Phil B (author)fjr_scoot2012-11-05

Thanks. Apparently you have used these guides before.

coolbeansbaby68 (author)2012-11-05

Very nice phil

Phil B (author)coolbeansbaby682012-11-05

Thanks, Jim. I wish the original idea had been mine.

coolbeansbaby68 (author)Phil B2012-11-05

Thats ok yours looks just as good

Bill WW (author)2012-11-04

Thanks Phil, a useful Instructable.

And I like your folding carpenter's rule, don't see these much any more.


Phil B (author)Bill WW2012-11-04


Thank you for the comment. That carpenter's rule was purchased new in 1970. I have used it a lot. The numbers on inside surfaces are still mostly like new. Those on the outside have suffered. Once a friend taught me how to unfold these rules in one speedy and continuous motion. I thought YouTube would have a video, but I do not find one. I may need to demonstrate here it one day.

Bill WW (author)Phil B2012-11-04

You said: "Once a friend taught me how to unfold these rules in one speedy and continuous motion.".

One of my strongest memories is when I helped my dad install an oil furnace at the family home in Indiana. 1951, I was 10. We were using his folding rule, which I tried to open in a speedy motion, and it broke in half. I was distraught, did not stick around to see my dad's reaction.

Phil B (author)Bill WW2012-11-05

"It's all in the wrist!" The movement involved with both hands needs to be carefully synchronized. If one hand gets ahead of the other, it would be very easy to break an otherwise good carpenter's rule. So far, I have not broken one, although I do not open one in rapid fashion regularly.

Goodluck (author)2012-11-05

A few things:

1) I find running the power cord up and over my shoulder does a nice job of keeping it out of the way and keeps it from snagging various things. If the wall with the plug is in front of you, use an extension cord long enough to loop it around behind you, then up over your shoulder.

2) In use, orient your clamps as pictured in steps 4, 5, and 6 (turning part down)as opposed to as show in step 3 (turning part up). Not only does that help prevent power cord issues, it also helps prevents the screw part from snagging clothing or poking you and surprising you while running a power tool (not good).

3) Long ago I realized cutting through the tops of my sawhorses wasn't a big deal (see a photo of them in my Treedle Lathe instructable). The biggest reason being that it supports both pieces after the cut. When they get worn out, I'll just build new ones. The ones I have are roughly 20 years old and I don't feel inclined to replace them yet.

4) Well done, I too wished I had known about such a guide many years ago. Without one, it is nearly impossible to cut a straight line. With one, a very simple operation. The only change I'd be inclined to make would be to glue the mdf trim board to the masonite. Screws may loosen or 'ream out' their holes with pressure and vibration over time.

Phil B (author)Goodluck2012-11-05

You make good points. I considered gluing the two pieces rather than using screws. One version on YouTube encouraged using screws because the edge of the Masonite could become damaged over time (in the estimation of the video's author). In that case, the screws could be removed and the Masonite could be shifted to one side a little. Then a new edge could be cut.

I did not want to cut into my saw horses because one of the supports is a steel roller I did not want to cut with my carbide blade.

Thank you for your comments and suggestions.

About This Instructable




Bio: I miss the days when magazines like Popular Mechanics had all sorts of DIY projects for making and repairing just about everything. I am enjoying ... More »
More by Phil B:Picture or Shelf Hanging FixtureMake an Electric Motor Run AgainMotor Made New McGyver Style
Add instructable to: