Question 1

the safety guard on my dewalt saw is stuck and won't retract automatically when i start a cut.

Accepted Answer

DIAGNOSIS The lower blade guard gets jammed with sawdust, wood chips, or even a bit of melted plastic from cutting laminates. It's a physical obstruction, not a spring failure. FIX Unplug the battery. Manually retract the guard by lifting the lever/ear on the side. Look inside the guard housing around the pivot points and where the guard meets the shoe. Use a stiff brush and compressed air to blast out all the debris. Work the guard back and forth manually. A drop of light oil on the pivot pin can help if it's sticky from sap. IF THAT DIDN'T WORK Inspect the guard for physical damage. Is it bent? Is a piece of the shoe bent and blocking it? A bent guard or shoe requires part replacement for safety. Also, the return spring could be disconnected or broken, which is a less common but possible issue. HEADS UP Never operate the saw with a stuck or manually tied-back guard. That's asking for a serious injury. If you can't free it up safely, it's time for professional repair.

Question 2

my saw feels underpowered and bogs down instantly in 2x4s, even with a fresh battery. it's not the blade.

Accepted Answer

DIAGNOSIS If you've already ruled out a dull blade, this points to either a weak battery that can't deliver high amps anymore, or a problem with the tool's power regulation. FIX First, test with a different DeWalt 20V battery, preferably a high-capacity 5Ah or 6Ah one. The smaller 1.5Ah or 2Ah batteries can struggle with the high draw of a circular saw. If a known-strong battery works fine, your original battery is failing. If even a strong battery bogs it down, the issue is in the saw. IF THAT DIDN'T WORK The problem could be the brushes in the motor are worn out or sticking. On the DCS570B, the motor brushes are not user-replaceable without significant disassembly. This would require a motor service or replacement. HEADS UP Also, make sure you're using the right type of blade. A framing blade with 24 teeth will rip through a 2x4. A fine-tooth finish blade (40+ teeth) will bog down because it's designed for slower, cleaner cuts in plywood.

Question 3

how do i change the blade on this thing? the spindle lock button doesn't seem to engage to hold the blade still.

Accepted Answer

DIAGNOSIS The spindle lock on the DCS570B is a little button you press on the top of the motor housing. If it's not engaging, it's usually because the blade isn't in the right position for the lock pin to drop into a notch on the arbor. FIX Hold the blade guard back with one hand. With your other hand, slowly rotate the blade until you feel a faint "click" and the blade stops moving. While holding that position, press the spindle lock button on top. You should feel it click and lock the blade solidly. Now use the provided wrench to loosen the arbor bolt (it's standard lefty-loosey, righty-tighty). The lock only works in that one specific blade position. IF THAT DIDN'T WORK If you can't feel any position where the blade locks, the spindle lock mechanism itself might be broken or jammed with sawdust. You'd need to open the housing to inspect it, which requires disassembly. HEADS UP Never try to hold the blade with your hand or pliers to loosen the bolt. Always use the spindle lock. And remember to check blade rotation direction when installing the new one—the arrow on the blade should match the arrow on the saw guard.

Question 4

the led light on my saw stays on all the time even with the battery off, is it draining my batteries?

Accepted Answer

DIAGNOSIS That's weird, but it's a known glitch with some units. The light is supposed to only come on when the trigger is pressed. It staying on indicates a fault in the switch or control board, not the LED itself. FIX The first thing to try is a hard reset. Take the battery off and leave it off for at least 2 hours. This sometimes allows any residual charge in the tool's capacitors to drain, resetting the electronics. Put the battery back on and see if the light behaves. IF THAT DIDN'T WORK If it persists, it's an internal electrical fault. The switch module or the small circuit board that controls it needs replacement. This isn't a user fix unless you're very skilled with electronics repair and can source the exact part. HEADS UP Yes, it will very slowly drain a battery if left attached, as the light is powered. Always physically separate the battery from the tool when storing it if you have this issue, until you get it repaired.

Question 5

dust blower on my dewalt circular saw doesn't work at all, just fills my cut line with sawdust.

Accepted Answer

DIAGNOSIS The dust blower on the DCS570B is just a simple channel that directs air from the motor fan. It's not a separate part. If it's clogged, you get no air. FIX The exit port is right in front of the blade guard. It's a small hole. Get a thin stiff wire (a paperclip works) and carefully poke it into the hole to clear any packed sawdust. Then, use compressed air to blow backwards through the exit port and also into the intake vents on the motor housing. Do this with the battery out. IF THAT DIDN'T WORK If the airway is clear but you still get no air, the motor fan itself might be damaged or obstructed. This requires disassembly to inspect the fan blade on the motor shaft, which is a more involved repair. HEADS UP This happens a lot when cutting MDF or really resinous wood that creates fine, sticky dust. Make clearing that port part of your post-job cleanup routine.

Question 6

my saw is making a horrible grinding noise and sparks are coming out near the blade when i try to cut.

Accepted Answer

DIAGNOSIS Stop using it immediately. This is almost certainly a failing motor bearing or, more likely, the arbor (the shaft the blade mounts to) is damaged. The sparks are from metal-on-metal contact inside. FIX First, with the battery removed, try to wiggle the blade side-to-side. There should be virtually no play. If it wobbles, the arbor bearings are shot. The fix is a motor/arbor assembly replacement. This isn't a user-serviceable part; the entire motor module needs to be swapped out by a DeWalt service center. IF THAT DIDN'T WORK If the blade is tight but it still grinds, remove the blade and inspect the arbor flange (the big washer that holds the blade). Look for scoring, burns, or debris stuck to it. Also check that the inner blade washer isn't missing—the blade must be sandwiched between two washers. HEADS UP This kind of damage can sometimes be caused by using a warped blade, a blade with the wrong bore size (must be 5/8"), or overtightening the blade bolt. Always use the wrench to tighten, but don't use excessive force.

Question 7

the blade on my dcs570b won't stay square to the base, it keeps drifting no matter how tight i make the bevel lock.

Accepted Answer

DIAGNOSIS Yeah, this one's common. The bevel lock knob isn't the culprit. The problem is usually the pivot bolt or the detent mechanism under the shoe (base) has gotten gunked up with sawdust or worn. FIX Unplug the battery. Loosen the bevel lock and tilt the saw to 45 degrees. Look at the pivot point where the shoe meets the saw body. Clean out all the compacted sawdust you can see with a brush or compressed air. Then, apply a drop or two of light machine oil (like 3-in-1 oil) to the pivot bolt and work the bevel back and forth. Tighten the bevel lock firmly, but don't hulk out on it—it's a fine thread. IF THAT DIDN'T WORK The detent plate (the little metal piece with notches for 0 and 45 degrees) might be bent or damaged. You can inspect it by removing the shoe, which involves taking out a few screws. If it's bent, you'll need a replacement part. HEADS UP Regularly blowing the sawdust out of the bevel mechanism after use will prevent this from coming back. It's a maintenance thing, not a design flaw.

Question 8

my dewalt 20v circular saw just stopped in the middle of a cut and won't start again, the battery is charged.

Accepted Answer

DIAGNOSIS You've likely tripped the electronic overload protection. It's not a mechanical failure; the saw's brain is just taking a nap because it got too hot or bogged down. FIX First, pull the trigger and hold it for a solid 3-5 seconds. Sometimes that resets it. If that doesn't work, pull the battery off, wait 30 seconds, and pop it back on. Try the saw. Still nothing? Try a different 20V DeWalt battery you know is good. The problem is almost always the protection circuit or a battery communication hiccup. IF THAT DIDN'T WORK If a known-good battery doesn't fix it, the issue might be the trigger switch itself. It's a common wear point. You'd need to open the handle housing to check for a broken wire or a failed switch, which is a job for DeWalt service or a confident DIYer with the right tools. HEADS UP When you get it running again, avoid forcing the saw through thick material or using a dull blade. That's what causes the overload to kick in. Let the tool do the work at its own pace.

DeWalt 20V Max Circular Saw DCS570B

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