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[edit] Using a hand held power saw.
All the saws I have seen in this category are designed for right handed use.
That is, for a right hander when you are sawing in the normal position, the blade guard is between your face and the saw blade.
If you are a left hander be aware that any chips of sawdust, etc. are flying out on your side.
So don't forget your safety gear. Not just left handers of course.
[edit] General Usage
If you buy one of these circular saws it will probably have a plain HSS (high speed steel) saw blade in it. Get a TCT blade if you can afford it, as they are so much more durable, especially in tough hardwoods. Also plywoods and composite boards are hard on blades so TCT blades are needed on them.
Don't dismiss the HSS saw blade, though, as so many do, it may come in handy. It's a good standby. You can always sharpen it yourself. Unlike TCT which has to be sent away.
I ripped up a pile of boards once to make strips for doing a stripped plank deck on a boat that I had. The fact that the HSS blade was thin meant I could get two more strips out of each board.
As a general rule it is said that you shouldn't have much more of the blade showing than you really need for the job you are doing. So to cut 40mm thick timber, set your blade to about 45mm or 50mm. This helps to minimise kickback.
Keep your saw guard in smooth running condition. It should spring back in place as soon as you lift the saw off the work. It should slide up smoothly as you push onto the work. Make sure it's DOWN before you put the saw down.
[edit] Using the saw guides
In these photos I am using my 160mm Makita circular saw. When I am starting the cut, I look down the face of the right hand side of the blade and line it up to the pencil mark.
I then look at the front of the saw to the two guide notches. The right hand one is a guide for cutting with the blade set in the normal position, and the other one is for when I have the base angled at 45 deg. So I line the notch up to my pencil line.
When I start cutting after a quick check to the front of the blade (photo 1) I keep my eye on the guide (photo 2) all the time.
This puts me in a natural position looking forward along the pencil line, and out of the way of any sawdust. The guard is between my eyes and any flying crap. ( use protective glasses of course).
As soon as I get into the cut I make sure that I am keeping the base of the circular saw flat on the timber being cut.
[edit] Handling Kickback
Kickback is a fact of life for anybody who uses a circular saw often. It is caused by the timber that is being cut, bending in some way, so that it jams on the back of the blade, making the saw buck or stall.
In the sketch above when all is going well the action of the teeth cutting into the timber at "A" helps to keep the saw bed and the timber in close contact. If the timber starts pinching the blade at "B" the opposite happens, the saw wants to climb out of the timber. Sometimes with a vicious jerk. The easy answer is to not let the timber bind on the back of the blade.
In the sketch above I have a length of 150 x 50 (6" x 2" for you metrically challenged :-) sat on a couple of saw stools. I can with my nice sharp saw slice straight through it at point "B", holding the main length of timber with my left hand, and letting the offcut fall to the ground. No sweat, except that there will probably be a big rough split on the end because I needed another hand to support the offcut. (I am right handed). A better way to do it would be to cut at point "C", where, as I am getting almost through the cut, I support the offcut with my left hand, and in such a way that I help the cut to open up. If the timber wants to slide about on the stools I clamp it down. I might think that it would be OK to cut through at point "A" , holding one piece with my left hand and letting the other drop to the ground. (Splintered again). It is fairly safe, but I have another thing to consider. Look at the sketch below.
What I have to do is stop this happening. The two ends on the stools want to stay put, but I'm pushing in the middle, and as soon as the bit of timber left to cut becomes small enough the whole lot wants to bend, and sure enough, bind on the back of the blade.
An easier way altogether is when you are cutting a lot of pieces up, you use some of them to make a bench. Then with a few lumps of offcuts under the one being cut you can go for it. Or, make a bench out of a couple of planks. Or failing that, cut on the ground, using packers and one foot on the timber being cut. Below is a sketch of a bench set up.circular saw cutting
To sum up, once you know what causes kickback, you are almost there to preventing it.
Clamp your work firm if you can.
Support in some way heavy offcuts, small ones are no problem. If you are cutting off rafter ends to fix a fascia, you should either have them precut to size before you fix them, or close to it, so that the offcuts are small enough to be no problem. That way you have one hand to hang on with and one to cut with.
[edit] See Also
[edit] Author
Bill Bradley
More DIY and home improvement pages on my website. Bill's site
