Festool PN574332 User Manual

24 

Domino DF 500 Tenon Joiner 

Motor does not start  

1. 

Check that the cord is properly plugged into an outlet. 

2. 

Make sure the outlet has power. Check the circuit breaker or try another outlet. 

3. 

If used with a Festool dust extractor, make sure the selector switch is pointing 

to "Auto". The auxiliary outlet on the dust extractor has power only when the 

selector is at Auto. 

4. 

Inspect the power cord (including extension cords) for damage or missing 

prongs. 

5. 

The motor brushes may have worn and need replacement.  

Plunging action is not smooth 

► 

Clean the linear rails and bronze bearings of the plunge slide, and make sure they 

are properly lubricated (refer to the Routine Maintenance instructions on page 

► 

Inspect the bronze linear bearings for damage. Improper insertion of the fence 

body onto the motor housing can damage the linear bearings. 

Domino tenons are too loose 

► 

Make sure you hold the Domino joiner firmly in position while plunging the 

mortise slot. 

► 

Make sure the mortise width setting is correct. 

► 

Make sure you are using the correct mortising bit for the size of the Domino 

tenon. 

► 

The Domino tenons may have shrunk in an overly dry or warm environment. 

This is normal wood movement. 

► 

Check the mortising bit to ensure it is not bent. A bent bit will make a thicker and 

wider mortise slot than desired. 

Domino tenons are too tight 

► 

The most common cause for this is that the tenons are stored in a humid 

environment, and they have swelled from moisture absorption. Store the tenons 

in a cool dry environment. 

► 

The mortising bit may have been improperly sharpened or sharpened too many 

times. Replace the bit.  

Workpiece joints are misaligned 

horizontally 

► 

Check the calibration of the locating pins. 

► 

Check the calibration of the Horizontal Position Gauge (sight gauge). 

► 

Don’t plunge the mortising bit into the work too fast. This may cause the joiner to 

move during the plunge. 

► 

Make sure the friction pads on the front of the joiner are not worn, damaged, or 

missing. 

Workpiece joints are misaligned 

vertically 

► 

If the mortise slots were registered from the bottom of the baseplate, make sure 

there is no dust or debris under the joiner. 

► 

Make sure the fence is properly locked at the desired height setting. 

► 

Inspect the height adjustment lock to ensure it is not broken (slipping).  

Tilted or misaligned mortise slots 

► 

Make sure the fence is set to the correct angle (e.g. 90 degrees). 

► 

Make sure to hold the Domino joiner firmly to the work surface. 

Workpiece joint won’t close (gaps 

between pieces) 

► 

Make sure the proper plunge depth is set. 

► 

Make sure the joiner is tight to the face of the workpiece. 

► 

The mortising bit may have been sharpened too many times and is too short. 

► 

Excessive dust may be present inside the linear slide. 

Tearout or rough mortise slots 

► 

Plunging speed too fast. Slow down the rate of your plunge. 

► 

Low-grade materials and plywoods will tear out more than solid woods. 

Decreasing your plunging speed will improve the results but may not eliminate 

the problem completely. 

► 

Dull mortising bit. 

Tapered mortise slot. The Domino 

tenon fits only part way into the 

slot 

► 

The plunge speed is too fast and the bit is not cutting the sides properly. Slow 

down the plunge speed.