If you are going to separate job sites with your miter saw or if you have a work site far from your home or office, you will have to fold and transport your saw on a regular basis. During the transportation, the miter saw may get out of alignment as a result of general movement, shocks, and bumps along the way. Besides that, job site hazards can also cause misalignment.
Though the safety of the miter saw is not affected by alignment issues, cutting accuracy will be greatly affected. When this happens, you will need to take the time to tune up and calibrate your saw if you want to end up with great cuts every time.
Here are some tips to help you tune and calibrate your miter saw properly:
Performing miter cuts requires a well aligned saw, or else the angles will be incorrect.
- Clean the Saw
The first thing to do is to clean the saw thoroughly. Blow sawdust away using air compressor or plug in a shop vac and suck the sawdust and debris from around the blade and saw base. Use a clean cloth to wipe down the whole tool, including the moving parts. Make sure that there is no pitch build-up on the entire saw. If there is, you can remove it using a rust and stain remover.
- Check the Blade
Before you make any changes to the saw, it is advisable that you check the blade of the saw. If the blade is in bad condition, no amount of tuning or calibration will help it to make a great cut. In fact, you may find that in some instances it is only the blade which is causing the saw to cut improperly. Changing the blade may solve your calibration issues. Make sure that blades are clean and sharp, without any warped or bent sections.
If the blade is in good condition, you can proceed with regular alignment adjustments. Whenever you want to adjust the alignment of your saw, it’s useful to put the blade which you want to use on the saw first. Making alignment changes and then switching to another blade may affect the way the saw cuts, causing your calibration to be pointless.
A miter saw blade in prime condition.
- Fence and Table Alignment
Regardless of what you might think, miter saw fences can be pushed out of alignment over time. Newer models of miter saws feature flat table bases which are very strong and provide a working platform. However, you shouldn’t trust this platform to be level and accurate until you have tested it for yourself. Older miter saw tables need regular checks as they can be knocked out of alignment more easily.
Finding out whether the the table is still flat is no big deal. You can do so by placing a metal straight-edge along the top of the table. Take a look at the straight edge to see how it laps on the table. If there are gaps between the table and straight edge, then it is not flat. If you have a level, you can also use that to check the various parts of the table. Just because the table is straight and flat doesn’t mean it is perfectly level!
The next thing to do when you have ascertained that the table is flat and properly leveled out is to check the fence located at the table’s edge to ensure that it is straight. You can use the same method to check the fence as you did with the saw table. Lay your straight edge across the length of the fence (on both sides of the saw table) and check for any gaps.Depending on the saw table you’re using, fence adjustment can differ. Many newer table designs operate by letting you loosen the mounting of the fence and adjust it into a new position. If it is a fence that has multiple parts, make sure that you straighten all the pieces individually.
- Miter Angle Alignment
When you have straightened the fence, you can now check and set the miter angle. Start by adjusting the bevel angle of the saw’s blade to 0 degrees vertically and horizontally. Do the same to the miter angle, making sure that it is squared to the fence. Lower the saw so that the blade will be in its lowest possible position, then slide the square against the blade’s side edge. Some models may require the blade guard to be raised in order to access the side of the blade in this position.
One edge of the square should be secure against the blade’s side while the other is against the saw’s back fence. Check for gaps between the blade and fence. If there are any uneven gaps, then you have to loosen the tightening knob of the miter saw and set it properly so that the blade will be straight and squared to the fence. Keep the angle in place by tightening the knob again. Make sure that the saw’s zero degree detent is accurate by loosening and adjusting the screws on the detent plate.
- Bevel Alignment
You should also make sure that the bevel angle is at zero degrees and squared to the table. Angles you have set before, whether your miter saw bevels both left and right or only in one direction, can be adjusted later on if you have accurately set the 45 degree angle and the 0 degree angle.
- Checking for accuracy
After you have set and adjusted all the parts that require alignment adjustment, you should now check for accuracy. You can do this by doing a few basic crosscuts at 0-degree miter and 0-degree bevel. Use a square to check the accuracy of the angles obtained. If you did not get perfect square cuts, then you have to readjust the saw until you are able to obtain a perfect square.
- Other Tune Up Tips
As mentioned earlier, when a saw blade becomes dirty it can be knocked out of alignment. You can reduce the chances of this happening by ensuring that the dust collection methods of your miter saw are working properly.
Keep in mind that most dust collection systems only work on a small percentage of the dust that’s given off by the saw. A regular dust bag that might come with your saw will not be very effective. However, you should still check to see if the bag needs to be emptied, if there are any holes in the bag, or if the connection ports are tightly sealed.
Most miter saws allow you to hook up a shop vac to collect dust more effectively. If you have this option, check your shop vac hose and all connection ports to make sure they are sealed tightly without any holes or gaps that might allow dust to escape again.
If you have a sliding compound miter saw, give the sliding mechanism a short test run to make sure the play is not too strong and to see if the bearings are still work properly. If the sliding supports are not working effectively, you may need professional support to find the problem and solve it. Too much play in your sliding cuts will potentially mess up your crosscuts, no matter how well aligned the saw is.
Keeping your saw well aligned is up to you, and you can repeat these steps as often as you want in order to have a precise cut every time. Once you learn how to do these basic calibrations and tune ups on your miter saw, you’ll quickly master the processes and be able to do them within just a few minutes!