This is the third post in a series of table saw alignment articles.
Verify and align the rip fence.
What are we trying to accomplish?
Straight rip fence
- The rip fence to be parallel to the rip fence.
- The face of the rip fence to be perpendicular to the main table.
What is the effect when the rip fence is out of alignment?
If the fence is slightly out of alignment one side of the cut wood will have slightly more saw marks than the other. One side of the wood will have a slight cove cut to it. On a piece of 3/4” thick stock it will be difficult to see the effects.
When the fence is more out of alignment, the saw blade cuts will be more pronounced on one side of the cut and the cove will become more obvious. If the riving knife is installed it may begin to effect the cut and either pull the board away from the back of the rip fence or push it into the back of the rip fence. Boards will not be cut straight; this will be especially obvious on longer boards.
If the fence is really out of alignment, there is a significant risk of kick back. The riving fence will help prevent it. Also there is a greater risk of jamming the saw blade and damaging the drive belt.
Alignment process
Safety First
Unplug the table saw.
Rip fence straightness
Check the rip fence for straightness. Using a straight edge check the straightness of the fence. There should be no gap greater than 0.002”. If it is not, replace it. Even after aligning the fence to the saw blade the cuts will be messed up because of the bow in the fence. Potential sources for a replacement fence are: local classified ads, craigs list, Ryobi, and eBay.
Aligning the rip fence
Unfortunately the rip fence’s alignment mechanism is quite crude. To adjust the alignment, unlock the rip fence, and then loosen the two screws on the top of the rip fence.
A simple home made jig is required to set the alignment. The jig consists of a scrap block of wood with a screw threaded into it.
Raise the saw blade up almost to the top. Mark one of the teeth of the saw blade with chalk. This saw tooth will be the reference tooth. Position the jig and rip fence so that the screw is almost touching the saw blade. Adjust the screw so that it barely touches the saw blade. This is the reference point or ‘zero point’.
Rotate the reference saw tooth to the back side of the table. Position the jig against the rip fence and slide it toward you until the screw is next to the marked saw tooth. If the screw head barely touches the saw blade the rip fence is in alignment. If the screw head protrudes past the saw blade then the rip fence is angled toward the saw blade. If there is space between the screw head and the saw tooth, then the fence is angled away from the saw blade.
In either case, adjust the rip fence adjustment screws until the fence is parallel on the front and back sides of the saw blade. For the angled away case, use a feeler guage to measure the distance of the gap. If the distance is less than 0.004”, leave the alignment alone.
Once the rip fence has been aligned it should stay aligned during normal usage. Whenever the rip fence rails are repositioned, check the alignment of the rip fence rails and the rip fence.
