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Rick Potter
03-01-2007, 4:30 AM
Went to the church last night to install some light fixtures in an old building we are remodeling. At the same time the AWANA leader (kids club) was setting up to make some simple boats for a race the kids do every year. The boats are a simple 1X4 about seven inches long cut to a point on the prow, with a dowel for a mast. The kids do the rest.

Anyway he and a helper, neither of which know anything about tools, started cutting them up with a borrowed chop saw. Simple cuts...pine...longest cut is four inches. They had fifty or so to make. After a while they came to get me, saying the saw blade had gone bad.

I went to look and found the 10" blade had buckled about one inch, took out the bottom insert, and came around and buried itself an inch and a half in the aluminum part of the upper blade guard. I have never seen anything like it. I took it apart to check if the blade had come loose, but it hadn't. The arbor was straight, the motor was not loose. As I said, the blad was buckled an inch, and there was a tear in the blade about that long where it had hit the saw.

Since the job was not done and the saw ran ok, they went to HD and got another blade. Half an hour later they came to get me again. The new blade did the same thing again.

I cannot see how they could have heated the blade enough to warp it that much. The cuts were not that big. Carbide 60 tooth Oldham blades. It was a decent saw..a 10":confused: Delta.

Anyone have any thoughts??

Sure glad I didn't have to return that saw to the owner.

Rick Potter

Ron Blaise
03-01-2007, 6:11 AM
Could they have but the blade on backwards?

Steve Kohn
03-01-2007, 1:12 PM
Pushing (maybe better said driving) the blade into the work before the saw was running at speed? Then they have the effect of pushing a stationary blade into a hard stop.

Rick Christopherson
03-01-2007, 1:34 PM
There is not enough information, but I am guessing that they were using a stop block to make their cuts and the offcut was actually their workpiece (i.e. trapped between the blade and stop block, but not controlled by the operator). The result can be a rotational kickback with a lot of lateral force. The kickback pushed the blade into the saw.

Rick Potter
03-02-2007, 2:43 AM
I am going to ask the Awana leader about feed speed and stop block Sunday. I will let you know.

Rick P

John Durscher
03-02-2007, 7:42 AM
My guess would be that they did not have the boards flat against the fence when doing their angle cutting. If they are cutting a point on a board I would bet that instead of changing the angle of the chop saw that they were holding the board at an angle away from the fence. When the blade paritally cuts the board it grabed the board and slammed it into the fence, twisting the partially cut board and bending the blade. Probably lucky their hands didn't get pulled into the blade when the boards took off.

John

"Gary Brewer"
03-02-2007, 12:59 PM
Rick: Ask them to cut a few of the boats while you watch. I'll bet you find the problem.
Gary