Engravers Network-Dahlgren System 300 General Tips

System 300 General Tips

Engraving Motor Sensor - recently my engraving motor was changing speed up and down during operation. After I examined the engraving motor, I figured the problem was with dust on the motor pulley sensor. It is located on the outside top of the motor pulley. It has three divisions of `shiny' areas - the speed sensors. This pulley should be approximately .030 from the holding bracket. I removed the dust from the sensor area, and readjusted the space between the pulley and the bracket.
Recently I was having problems with my older System 300. It was blowing fuses, and the run bottom was not functioning 100% of the time. The RUN button membrane was also broken from repeated attempts to engage/disengage. The fix required a new power supply, and a new front membrane.
When using your Arc'ing option on your Dahlgren, the letters are not arc'ed, only their appearance as a group. Several members have tried unsuccessfully to use the lines in the utility font to underline arc'ed letters. Although a letter in a font set or a logo may be condensed or expanded, it cannot be distorted to the contour of the arc.

Regularly remove the accumulation of chips under the leadscrew cover beneath the table. The buildup of chips can cause leadscrew binding, and prevent the table from returning to it's Home position.

Recently I was having trouble with my System 300. The X & Y axis were moving very erratically, and you could hardly read the engraving.

I put the engraver into the SLEW mode (switch on the back of the SCU), and SLEWed it several times. When the spindle came back to the HOME position, the Y-axis was at 0, but the X-axis was usually at 1-1/2 - 2 inches to the right of its HOME position. I turned off my SCU and swapped the X & Y-axis leads. After SLEWing several times, they were in the same approximate position before I swapped the leads.

Thinking it was probably my X-axis motor, I turned the knob on the end of the motor shaft and noticed it had a much rougher rotation than the Y-axis.

I started taking the motor off. After removing the last socket head screw holding the motor, the motor fell off in my hand. Normally I would have had to loosen the helical coupling between the motor shaft and the X-axis leadscrew to remove the motor.

Apparently I had a hairline crack in the helical coupling and the weight of the motor caused it to break completely.

The coupling was a lot cheaper than what the stepper motor would have cost to replace..

As a general rule, if you swap the X & Y-axis leads and the problem remains the same, it's probably the stepper motor, leadscrew bearing or the helical coupling as above. But if you swap, and the problem moves to the other axis, it's probably a stepper board or other PC board.)

I have found by waxing underneath my System 300 and System 1 tables, it makes cleanup a lot easier. I use Johnson's paste wax. Be sure and don't wax the top of your table or you can't tape your plates down.

System 300 Engraving Quality Problem

Beyond the usual problems associated with mis-adjusted leadscrew nuts, you may be finding problems caused by worn bearings in the X-Axis slide.

The first thing to do in these cases is to eliminate all other possibilities that might cause the poor engraving quality. In the Default settings, set the engraving cut speed to 190, and the move speed to 110, with ramping off. See what kind of improvement this offers. Make sure the cutter is sharp, and the spindle is properly set in the assembly.

Next, make sure that the problem occurs exclusively on the X-Axis. Engrave 3 utility boxes and note which lines have the worst ``wiggle''. Then engrave the same job with the plate orientation of Left Sideways, and verify that the wiggle is still on the axis in question.

If you are certain that the problem is the X-axis slide, you will need to replace the bearings in the X-Axis slide

SYSTEM 300 TABLE. Have you ever lost you engraving motor speed control, and it starts running wide open no matter how much you try to adjust on the SCU panel?

Recently I was changing a belt on my 300. I loosened the two set screws on the pulley shaft and slid it upwards toward the motor so that I could remove the belt. When I installed the new belt, I decided that I would leave a larger gap between the pulley and the lower mounting housing. The increased gap would make it easier to change belts the next time. When I started engraving I noticed that I had lost my engraving motor speed control.
: I retraced my steps and found a sensor on the bottom of the pulley. After lowering the pulley to the original position (1/16 inch between the pulley and the motor housing) I regained my speed control.
: If you lose your speed control and you haven't adjusted the pulley, check to see that the sensor is free of oil and other debris.