Kickback happens when the blade catches the workpiece and violently throws it back to the front of the saw, towards the operator. It can be thrown very hard and can injure the operator. It is not uncommon for the object to have high enough velocity to become embedded in a wall or to cause other damage or injury. Never stand in a direct line between the blade and the fence when ripping narrow stock. A kickback can be fatal.
Kickback happens when ripping if:
The wood pinches the blade because of internal stresses. This is difficult to predict and can be impossible to control when using fingers to hold the wood down. Many times the board pinches the blade and is thrown back before the wood reaches a splitter. This type of kickback never happens when a board is not cut all the way through (dado). By starting a cut with a dado and then raising the blade to leave a splitter tab of uncut wood, this type of kickback can be avoided, but raising the blade during a cut cannot be done unless anti-kickback hold downs are used, so it is safe to raise the blade with a free hand.
The wood is allowed to raise up or moved sideways during a cut, then pushed back down, taking too big a bite at the top of the blade. This can be prevented by using feeder wheels very close to the start of the blade and hold downs after the blade to control the wood all the way through the cut. The right feeder wheels are very effective for both dados in plywood and for rip cuts on boards as narrow as 1/8". Feeder wheels can be powered or unpowered, clamped or held magnetically, and replace fingers near the blade so a hand can be free to turn off the saw during a cut.
The board is pinched between the rear of the blade and the fence. The fence should be parallel with the blade, for the best cut on both sides of the blade. The fence can be set with the rear farther from the fence for safety, but at the expense of upcut marks on the "waste" piece. Never allow the fence to be closer to the rear of the blade than the front.
Kickback can also happen when crosscutting boards with internal stresses. A chop saw or circular saw is the best preference for cutting poor lumber.[citation needed]
The risk of kickback is reduced by certain practices:
The blade must be kept sharp and clean, something novice users may not recognize. The buildup of pitch on a blade greatly increases friction and increases the probability of kickback. It also decreases the quality of the cut, causing it to burn.
The saw must be aligned, adjusted so that it is parallel to the miter grooves, with the rip fence should angled minutely. If the blade is parallel with the fence you will notice the marks made by the back of the blade on the wood. It is possible for the workpiece to be pinched between the blade and the rip fence, which will cause violent kickback if the fence is closer at the back of the blade. The correct relationship for the fence is minutely spread which means that the angle is different depending on the side of the blade the fence is set.
The blade guard should be used whenever possible. Typical table saws incorporates a riving knife, a spreader which helps prevent the cut from closing on the back of the saw blade. Natural tension can exist in wood that causes the cut to close. Some blade guards have anti-kickback devices that allow only forward travel past the blade.
Push the workpiece past the blade. Do not release a workpiece until it is past the blade and removed from the saw. Turn the saw off before removing small cut off pieces.
Always maintain control. Do not execute a cut where you do not have complete control of the situation. Make sure there are no obstructions. Do not cut a workpiece that is too large to handle.
Do not use the rip fence as a guide during crosscuts. If you need to make a series of equal length crosscuts, use a stop block in front of the blade so the workpiece is not in contact with the rip fence during the cut. It is easy for the workpiece to twist out of perpendicular at the end of the cut and thus get caught by the blade and thrown.
Check for flaws in the wood. Cutting through a loose knot can be dangerous. Cutting a warped or twisted board along the rip fence is dangerous because it can get pinched between the fence and blade.
| Manufacturer | Kreg Tool Inc |
|---|---|
| Part Number | PRS3020 |
| Item Weight | 1.1 pounds |
| Product Dimensions | 9 x 3 x 7.5 inches |
| Item model number | PRS3020 |
| Is Discontinued By Manufacturer | No |
| Size | 1 Pack |
| Color | Blue |
| Material | Metal |
| Item Package Quantity | 1 |
| Number Of Pieces | 1 |
| Mounting Type | Plate Mount |
| Included Components | Kreg True-FLEX Feather board twin pack (PRS3020). |
| Batteries Included? | No |
| Batteries Required? | No |
