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I am new to woodworking and I tried my ''new'' secondhand table saw (General LR63420 Model D) today. It cut through the first few chipboard boards just fine but then had a lot of trouble going through the middle of a 4 x 8 chipboard board. I am pretty sure I did not squeeze the blade so I am wondering whether it could be a belt or blade issue.

What should I look for/change first?

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    Was the blade slowing down? Was the blade burning the wood?
    – JACK
    Dec 30 '19 at 23:06
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    Some motors have thermal cutoffs. Make sure the entire table saw is clean, then vacuum any vents. Make sure ventilation is working correctly, and make sure any fans or breathableopenings are not blocked.
    – noybman
    Dec 31 '19 at 1:05
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    Also a common mistake with beginners is to set the blade way too high. Usually you want to set the blade such that the top of the blade is barely going through the material. This uses as many teeth as possible on the blade to cut, and causes the cut to be much smoother because each tooth isn't trying to take out such a big chunk of the material.
    – Ron Beyer
    Dec 31 '19 at 16:19
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    Can you be more specific about what you mean by "stops"? When you remove the wood does it run? When it stops, does the motor hum loudly and do the lights dim? When it stops, does the motor make its normal running sound? Dec 31 '19 at 18:01
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    @EricLippert It's much better than marginal, IMO. 1/8" less (say) of a cut to your body could mean tremendously less of an injury, eg if it missed a nerve, bone, etc. vs cutting it. Jan 1 '20 at 12:04
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  1. What is the horse power of the motor?
  2. What is the rating of the circuit breaker?
  3. Are you running on an extension cord?

Circuit breakers can take some time to trip if the overload is small. As the motor slows, it draws more current.


If a saw has been moved, it may no longer be in alignment. Using a vernier caliper check that the blade is parallel to the miter slots. To do this, mark a tooth with a felt pen. Put the tooth just above the center plate on the leading edge, then repeat using the same tooth at the trailing edge. The numbers should be the same to within a few thousands of an inch.

Next, check that the fence is parallel to the miter slots. This is easier. Slide the fence adjacent to the miter slot and lock it. Again, it should be parallel to a few thousands.

That saw, I think is a cabinet saw, with the saw mounted on the base. Adjustment is usually done by loosening the bolts that secure the top to the base. Should say in the manual if that came with the saw. If not, google it.

In passing: Chipboard is hard on blades. I buy Freude 7.25" circular saw blades on sale for rough work. As a smaller diameter, there is more torque and the saw bogs down less. It's also a thinner kerf. Finally, if you do bind the blade, stuff coming at you is only moving 45 mph instead of 70.

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    "Buy on sale." Key phrase. +1
    – bishop
    Dec 31 '19 at 2:40
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Examine the blade disk to see if it has become gummy or coated with resin. You may have to remove the blade and scrub it clean.

If the saw is not new the blade may be quite worn and need replacement.

The teeth of a saw are bent slightly to the side (usually every other tooth to each side) to make the cut wider than the saw blade. Sometimes a saw blade can seem sharp but the projections formed by the bent teeth are worn down, making the cut too narrow.

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There could be several issues that cause the blade other than a dull blade, you have hit on squeezing the blade with the rip fence and chip board will get chewed up a little even with some squeeze, since it’s not that a loose belt is another possibility and the last thing I have seen a few times is the pulley on the motor shaft or the saw arbor is loose, sometimes there is a key or a small square metal piece in the pulley to shaft connection that is normally held in place with a set screw through the pulley, if no key there will be a flat spot on the motor and arbor shafts that a set screw keeps the pulley from spinning on the shaft.

If the pulley has been spinning it may have done a little damage to the shaft, you may need to adjust the pulleys in or out if the flat was damaged severely but once tight and inline with the other pulley even a badly damaged shaft will work because it is a belt drive.

My son had the blade slowing down and tightened the belt so tight I was amazed it could slip or did not break the belt. Once we tightened the set screw his saw worked fine.

So I would be looking at a missing key and or a loose set screw if the belt is tight.

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It turns out it was a combination of the 2 following issues :

Underfed saw : My extension cord did not transfer 240V but 120V only

Old blade : Blade was pretty worn out

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    Yowsers! Running a 220v motor on 120. I'm amazed that it cut at all. Jan 3 '20 at 15:18

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