One Great Tip » Shop Made Circular Saw Guide
Working with big sheets of plywood, or worse yet MDF, can be a bear. Even on my cabinet saw, equipped with ample outfeed support, I dread man-handling those behemoth sheets. Its grunt work at best, and can be downright dangerous if the slightest thing goes wrong. I have stories among my circle of friends, and I will spare you the gory details.
The solution to this problem that can be found in some big-time cabinet shops and home centers is a panel saw, which is an amazing tool for quickly, easily and safely taming sheet goods. But two simple reasons prevent me and most other hobbyist woodworkers from taking the plunge into panel saw ownership. The first problem is price, and for me there don’t really need to be any other problems. At $900 for a basic model (and they go way up from there), I wouldn’t use it enough to justify the indulgence. Secondly, the dedicated footprint required for this tool is significant. Between the infeed space and the massive size of the tool itself, it is like having another stationary table saw for a specific task. These tools are impressive and a great asset for a shop, so if you have the space and the money, don’t let me talk you out of getting one. But if you are like me and don’t have one, the other or both, then read on.
As I looked around for options for breaking down sheet goods in my home workshop, I saw that there are many nice guide systems for circular saws that looked decent. Some guide systems even come with a circular saw, and these look like a great alternative to a panel saw. I knew I was getting warmer. But could I rig something like this up for my own circular saw, which cost $49 some 15 years ago and had mostly been used for building decks? I love cheap, but I hate junk. I wanted something that would deliver a chip-free edge on veneered plywood that would rival what a panel saw or high end guide system could deliver. If it compromised cut quality, I would go a different route.
My solution was a dirt-simple work around; an hardboard guide system that is made custom for my circular saw. Here are some of the things that I love about this system:
If I have successfully sold you on the idea of building one of these, let’s get started. First, the shopping list is pretty simple. You will need a 4’ x 8’ sheet of 1/4” hardboard and a bit of glue. That’s enough material to make an 8 foot long guide for ripping, a 4 footer for cross-cuts, and have lots of leftover material for future jigs.
First, cut pieces for base and fence. Cut a strip of hardboard 9” wide and whatever length you want your guide long. The one I am making here is 8’ long. Then cut a strip of hardboard 5” wide and the same length as the base, which will be used as the fence for your cutting guide. If you are tempted to keep the jig lighter by making the fence more narrow, be careful because the width adds rigidity which is critical for an accurate cutting guide, and it also provides more surface for clamping so that the clamp does not interfere with the circular saw operation (I just saved you having to throw away
your “rough draft” project like I did with mine.).
Glue the fence to the base. Use your favorite woodworking glue. Align the edges, but don’t worry too much as we will trim it later. 
Place glue-up on flat surface and add weight to hold flat. This will keep the cutting guide flat as the glue dries. As an alternative to weighting it down, you might choose to use short brads to secure the two pieces together. Whatever you choose, be sure to keep the pieces held against a flat surface while the glue dries.
Cut base. Leave the edge overhanging enough so that your saw blade will not cut into anything that you don’t want it to. Hold your saw base carefully against the fence as you make this cut, leaving you a base that is perfectly matched to your saw, with a zero clearance edge that will deliver a chip-free cut on veneers.
Trim the other edge. This is an optional step that will tidy up the guide. Place the non-fence side of your base against the fence on your saw, and adjust the fence so that you will remove material from both the base and fence of your guide for the entire length of cut. After this cut, the jig is complete.
Using the Guide
Place guide directly on cut line. Mark the plywood for your cut. Then lay the guide directly on the line, placing the guide on the side of the line that you will keep. This will prevent chip out from occurring on the project itself, because the base of the guide system will serve as a backer board for the cut. 
Clamp the guide in place. Place the clamps where they will not interfere with the path of the saw’s motor.
Make your cut. Carefully hold the saw tight against the fence and flat against the base for the length of the cut. Push steadily through the cut in one continuous motion.
Perfect edge. If everything was set up correctly, your sheet should be trimmed perfectly to size, with a chip-free edge where you made your cut.
Blade selection. Be sure to find a good blade for cutting veneer plywood, and not just go with the junky blade that came with your saw, which is typically designed for cutting framing lumber. Look for a blade with a high tooth count, in the range of 50-60, thin kerf to minimize resistance as you move through the cut, and carbide tipped teeth to maximize the time span between sharpenings.
14 Comments
I've used this type of jig for several years, and it's fantastic! About the only thing I might add is to trim one edge with your standard kerf circular saw blade, then, if you sometimes use a thin kerf high tooth count blade, turn the jig around and trim the other side with the thin blade. Be certain to mark the thin cut side, otherwise you'll be about 1/16" off on your cut. Don't ask me how I know that! :>)
Thanks for the comment. I like the concept of a double sided jig. Because I only use this by placing the jig on top of the "keep side" of the plywood, thin vs. full kerf doesn't make a difference like it would if you place the jig on the waste side. Another reader made an off-line suggestion to me that the other side of the jig should be used as a router guide for making dados, which I think is also a fantastic idea.
This is a great jig. I like the 1/4" thickness better than the 1/2" I am currently using. I gave mine a couple of coats of clear spray paint and then a good coat of paste wax to make it slick.
great idea to lacquer and wax the guide, Steven.
I bow down hmubly in the presence of such greatness.
Great idea. I've been using a 4" strep off the edge of a peice of 3/8" ply nd allowing its placement by deducting the width of the of the saw plate.
Hi kfbessel, Thanks for the comment. That is exactly the way that I had been doing it for years as well. You will love this new approach for two reasons. 1) put the jig right on the line and cut. super simple. 2) the "zero clearance" aspect improves the quality of cut tremendously. Even with my cheap old circ saw and a home center quality blade I get chip free cuts on veneer. Love it.
I've made these as well, they work great. Just had to make another as I switched to a thin kerf blade so there was a gap between the blade and my previous jig. Fortunately they're cheap and quick to make.
Hi WHWoodworking, Thanks for posting. If you place this jig on the "keeper side" of the project, and place the wider portion of the base on the track, then the thickness of the kerf should not effect the cut. If you place the jig on the waste side, or place the narrow part of the saw base on the track, then you would need to account for the thickness of the blade, which would be a pain. So if you build another one, when you cut the jig with your circular saw, be sure to position the saw so that the inside edge of the saw blade (the edge closest to the motor) is defining the width of the jig; not the outside.
Hi Paul. You are right about not making these guides too narrow. I built one a while back, before I read your article, that will bend in the middle given enough force. I am going to make a couple more and will follow your advice. I am thinking about trying 1/2" MDF for both the base and fence. I'd like your thoughts on this. Thanks
Done and used them with VERY positive results, minimal chipping even with melamine combined with a good blade. Like +++
Use one side as above and flip it around and use on the other side a straight bit in your router and use it for doing a straight edge and jointing. It works great!
Rod, I think 1/2" MDF would work but would be overkill. My only concerns would be 1) weight, and 2) clearance. This might not be a problem for some saws, but if the upper guide was 1/2" on mine, the saw would not fit flat on the base because the clearance underneath the motor is not sufficient. If yours has enough clearance, it would be fine.
I made mine for saw one side the other side for my router