In this video, we'll demonstrate how to check and correct table parallelism issues on a dovetail-style jointer, specifically using the Grizzly G0654 6-inch model. 

This video stresses the importance of correct alignment for precise woodworking and making necessary adjustments before starting your projects.

We've also included the step-by-step instructions below if you'd like to follow along.

• Disconnect Power: Always start by unplugging the jointer from the power source.
• Read Instructions: Refer to the written instructions that came with your specific jointer. Read and become familiar with your owner's manual in its entirety, including all safety instructions.
• Follow Shop Safety Procedures: Remember to follow all general shop safety procedures.
• Eye and Ear Protection: Always wear appropriate eye and ear protection.
• Technical Support: If you need further assistance, you can call technical support at 570-546-9663.

• Gather Tools: You will need a good quality straight edge (at least three-quarters the length of both tables) and a set of feeler gauges. A dial indicator can also be used for this step.
• Position Straight Edge: Place the straight edge on the infeed table so that it hangs over the cutter head.
• Ensure Squareness: When using a straight edge, it is crucial to keep it perfectly upright and square to the table. The video shows a simple wood block with a slot to help with this.
• Measure Distance: Using the feeler gauges, measure the distance between the body of the cutter head itself (not the knives) and the straight edge at each end of the cutter head.

• Assess Parallelism: If the difference in measurements at each end of the cutter head is more than three thousandths of an inch, it needs correction.
• Prepare Shims:
• You can make shims from thin material like a soda can (approximately two thousandths of an inch thick).
• Alternatively, the easiest method is to use the leaves from an inexpensive set of feeler gauges as shims, as they are already specific thicknesses and the correct width.
• Loosen Bearing Block Nuts: Locate and loosen the nuts between the base and the stand that secure the cutter head bearing blocks. Loosen them several turns.
• Lift Bearing Block: Slightly lift one side of the cutter head bearing block.
• Insert Shims: Place the appropriate thickness of shims between the bearing block and the mount it sits on.
• Tighten Nuts: Tighten the nut that you loosened.
• Recheck: Recheck the parallelism between the cutter head and the infeed table using the straight edge and feeler gauges.
• Adjust Shims: If necessary, add or subtract shims until the parallelism is within three thousandths of an inch across the length of the cutter head.
• Final Tightening: Once the parallelism is correct, fully re-tighten the cutter head bearing block nuts.

• Raise Tables: Raise both the infeed and outfeed tables so that they are above the cutter head. Some jointers may have stop bolts that need adjustment to allow the tables to raise this high.
• Position Straight Edge: Place the straight edge on the infeed table, spanning across to the outfeed table.
• Adjust Outfeed Table Height: Adjust the height of the outfeed table until it just touches the bottom of the straight edge. Be aware that if the tables aren't parallel, one end of the outfeed table might touch the straight edge first.
• Measure Gap: Once the outfeed table is touching the straight edge at one point, measure any gap between the straight edge and the other end of the outfeed table using the feeler gauges.

• Identify Shim Location: You will need to add shims between the dovetails of the outfeed table and the base casting. The outfeed table is typically shimmed because the infeed table is frequently moved for adjusting the depth of cut.
• Loosen Gib Screws: Loosen the table gib set screws enough so that the outfeed table can be slightly separated from the base.
• Insert Shims: Add thin shims equally to each side of the dovetail connection on the outfeed table until the table is parallel to the straight edge placed on the infeed table.
• Start with Small Increments: It's recommended to start with five thousandths of an inch of shims and work up in five thousandths of an inch increments until you get close to the correct alignment.
• Lock Table Movement: Remember to lock the outfeed table movement each time you recheck the parallelism.
• Recheck: Recheck the parallelism between the infeed and outfeed tables using the straight edge and feeler gauges.
• Adjust Shims: Continue adding or removing shims until the outfeed table is parallel to the infeed table.

• Set Outfeed Table Height: Once the infeed and outfeed tables are parallel, set the outfeed table level with the top of the jointer knives at their highest point of rotation.
• Snug Gib Screws: Lightly snug the table gib set screws to secure the outfeed table in its aligned position.

We trust you will find this video to be beneficial. Please feel free to reach out to us HERE if you have any questions on how to tune a jointer with dovetail slides.