circular saw cutting guide

[stav]

I made some of those.  The idea is to cut one edge of the a piece of ply off. Then you flip it so the factory edge is facing into the wide piece of ply and that acts as your straight edge.  It works great.  I have several.  I like the hard board for the bottom and a thicker piece of ply for the edge guide.

As they said in the article, a Freud blade on your circular saw will make a big difference.

[Cecil]

You ask if you should worry about kick back.  The answer is yes!  Worry is not the right term, concern is a better term.  Using the guide presented is one of the safest ways to use a circular saw.  Having good support under the work, but supporting the whole sheet on a piece of foam, on the floor, also improves safety.  However, like a table saw, always be aware of where you body is in relation to the saw.  Also, never defeat the safety devices, like the blade guard.

The guide they show in the picture uses heavier material than I used.  I used 1/4" MDF.  I have been cutting sheet goods that way for years.  I have a table saw, but I always break down the sheet goods with a guide and a circular saw.

[mike4244]

First of all cutting anything while on your knees is ridiculous.Make or buy a set of horses.Lay a couple of 2x4's across them. For cross cutting that's all you need. For ripping add 4'-0" long 2x4's across the long 2x's at each end and one more in the center.This will support full sheets.You can toe nail these pieces to keep them from sliding about if needed.Make sure the nails are not high enough to be in the way of the blade.
The straight edge guide shown in the video is okay,I would make it a bit differently.
The bottom piece is too thick, interferes with a full depth of cut if needed.Make it from 1/4" plywood.The top piece can be 1/2",3/4" etc.This piece should be straight,factory edge may be straight enough.The plywood bottom starts out extra wide,12" or so.Install the straight piece so when you initially make your first cut the guide can be used on the narrow edge of the saw base and the other side ,the wide saw base.I prefer using the narrow side myself.I would spot glue and screw the plywood to the top guide.The screw heads should be either countersunk or remove the screws after the glue dries.I mention this because  1/4" plywood may harder to countersink without pulling the head thru.
When making the first cut on each side of the guide piece you will remove the excess plywood and a straight edge is formed.When marking out dimensions the straight edge guide can be clamped to the line on each end.
Set the base so 1/4" of blade projects below the work to be cut.
I use to lengths, 8'-0" for rips and 4'-0" for cross cuts.

mike

[Cooler]

I've used 1/4" hardboard but my damp basement made them get wavy.  I now use 1/4" ply.  

You do have to make a new cutting guide for each new blade you use (unless you buy the exact same blade each time).  

I have the lumber yard make the big sizing cuts to make carting home easier, but I always have to trim myself.  

I cut the long pieces on the table saw, since I have a 48" fence.  

I only need it to cut pieces that are longer than 48" and wider than my radial arm saw can accommodate.

[jcredding]

I use a similar type of guide for my circular saw, but use door skin for the base. I have 4' and 8' guides and one each for 90 degree and 45 degree cuts. Just make the cutting side a little wide and your first cut will be to the edge of your blade. After that it's very accurate and I've never had a kickback problem.

[handi]

I sell plans for a guide rail that not only works with your circular saw, but also with a sled for your router. You build two sections that can be joined just like the extruded tracks. Made with 1/2" ply and common hardware.

PM me and I will happily send you the PDF plans for free.

[kurt18947]

If you make the cutting guide, I would suggest using 1/4" hardboard.  It's much lighter and works great.  I made 3 of them...lengths of 8', 4' and 2'.

That's what I used. For the guide strip I used some 1/4" thick aluminum skin/honeycomb center material. My thinking is that it's light and won't warp or bow like wood based materials might. So far so good. I'm sure a track saw would be better but I don't do enough of this work to justify it.

[JohnnyEgo]

$20 worth of 2x6s gets me a cutting surface where I can just lay a plywood sheet on it and go to town. You can get ready-made sawhorses up and down the price spectrum that are notched for 2x4 material. I saw a cheap plastic set at Lowes the other day for $30. So for $50, you could break down sheet goods pretty easily without having to bend over much or re position the sheet:




Likewise, a sheet of rigid foam glued to cheap plywood allows you to cut right on the floor or on the cutting table with better support for a full-sized sheet, at the expense of limiting your clamping options as the pieces get smaller.
I use the 1/2 ply backer because it keeps the foam sheet in better shape, and because it is convenient to flip it ply-side up and screw jigs, fixtures, or parts directly into the sheet sometimes. I cut my sheet in half to make it a little easier to store, and to allow me to only use half at a time if that is all I need.




I got this idea from here, quite possibly from one of the people above who are recommending it to you now, and I wish I had done this 10 years ago, when I was using a skill-saw and a home-made MDF guide to do my rough sheet breakdowns. These days, I save the tablesaw for small work, and cut all my larger pieces on the cutting table, and feel much safer that way.

[Cecil]

I also find I do not need a 4X8 support surface.  3x7 is plenty.  I never had an issue letting 6" hang over the edge.  Also, you only need to clamp the saw guide to the piece.  I never found additional clamping necessary.  I just use spring clamps for that.

[bennybmn]

I also find I do not need a 4X8 support surface.  3x7 is plenty.  I never had an issue letting 6" hang over the edge.  

That's a good point right there. A little overhang is fine as long as you cheat it so that nothing will fall once the cut is complete.

I also don't like spring clamps because they can shift...

I've been using a guide like the OP for years with great success. I'll also echo the 1/4 MDF suggestion, and 1/2" is thick enough for the "fence" part. Making it fairly wide is good too, because then whatever you use for clamps will clear the saw motor!  I also made a shorter (2'-ish) one that I used for cutting 1X12s down to length. They are juuuuust wide enough to be tricky to crosscut on my table saw, and I don't have a sliding miter saw. Handy little bugger. The zero clearance part of it is a nice bonus.