OWNER’SMANUAL

MF-12PINSPOTTER

MF-12MF-12

MACHINERY DIVISION

MF-12

TIMER ADJUSTMENT

The MF-12 has been designed and built to withstand rugged shop. Constant, trouble-free operation is as-sured with a minimum of maintenance. The GUN TIP, the GROUND CLAMP and all CABLE CONNECTIONSshould be kept clean to maintain a good electrical contact. Wire brush the parts to remove any oxida-tion or adhesive that may have accumulated during the fastening operation.

"HEAT SINK"

The timer dial facing you on the front panel of theunit, determines the duration of the weld cycle. Formaximum efficiency of the unit, the weld cycle should be set for the shortest length of time necessary toprovide a good weld. An excessive amount of time does not improve the weld. On the contrary, the resultingweld may not be an acceptable one. It is recommended that at the start of a production run, using a givenlength of pin with a given gauge of metal, the opera-tor take a few moments to determine the minimum timer setting to perform the job and leave the timer at that point.NOTE: There is a common misconception that thelonger the weld time, the stronger the weld. This isnot true. It is important that you follow the above instructions for maintaining the minimum weld time.

MAINTENANCE

Included with your MF-12 is a simple “heat sink” tool that looks somewhat like a cookie cutter. This tool,when placed behind the point of weld on bare metal,will eliminate any mark on the metal by dissipating the heat generated from the point of the weld. The use of a copper sheet on the work bench will also eliminatethis mark.

ELECTRICAL REQUIREMENTS

Where duct is too large to put on a bench, snap the ground clamp onto the duct and secure the insula-tion quickly by welding the Clip Pins inside or outside of the ducts as required. Eliminate the heat mark on the duct using the simple “heat sink” supplied on the opposite side of the weld.

BRING MF-12 TO THE WORK

MF-12 AS A BENCH TOOL

Connect the MF-12 to a 30 amp power supply. (208-230 volts – 60 cycle). The MF12 uses 208 – 230 volt single phase. To wire to 208-230 volt single phase, the green lead is ground and the white and black leads are power. It is suggested that the unit be permanently wired into a 30 amp disconnect box fitted with 30 amp slow blow fuses.

To use your work bench as a welding table, set theMF-12 alongside or on top of the work bench. Coverthe bench top with a copper sheet (.025 inch) which will act as a permanent ground when the duct workis placed on the table top. Attach the MF-12 ground clamp to the duct work or copper bench top. The Clip Pins will quickly weld every time with no burn marksor wasted pins due to misfires.

INSTALLING CLIP PINSClip Pins are welded as easily as "A", "B", "C".

"A"

Press down through the insu-lation, twist the gun, and pull the trigger. Do not release the trigger until the timer cycle has ended.

"B"

Position the Clip pin on the Magnetic tip of hand gun.

The Clip Pins are permanently welded in position flush with the insulation.

"C"

SERVICE The MF-12 has been designed and built to withstand rugged shop usage. The Indicator lights on the front panel will help you to diagnose minor problems. If your MF-12 fails to operate follow this simple procedure to find the defective component.

1. Pull the trigger and watch the lights. The green light (24 volts) and then the red light (220 volts) should flash on and off.

2. If only the green light comes on, go to step 4.

3. If neither light comes on, press the WELD CYCLE TEST switch on the front panel. A. If both lights flash and the transformers do not

hum go to step 5.B. If both lights flash and the transformers hum,

the problem is either a bad trigger switch or bad switch cable.

C. If only the green light flashes, go to step 4D. If neither light flashes, replace 24 volt trans-

former.

4. Replace the weld activator.

5. The problem is probably a bad weld transformer. Call technical service for further assistance.

(1-800-899-3876)

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MF-12 PARTS & SPECIFICATIONS

17049 Male Camlock17079 Rubber Foot17140 Weld Activator17288 Switch Cable Plug17309 Power Switch17313 Terminal Block17320 Weld Potentiometer17327 Switch Cable Receptacle27005 TP-2 Tip27007 Gun & Cable Assembly27008 Ground Clamp Assembly27009 Heat Sink27213 Female Flush Mount Camlock27217 Line Cord27231 Electrode Assembly27234 Gun Cable27235 TP-8 Tip27236 Fibre Sleeve27237 Electrode27238 Roll Pin27240 Case Screws27241 Switch Wire Assembly

27243 Gun Cable / Electrode27244 Brass Jack27245 Gun Switch27246 Gun Case27253 Line Cord - Strain relief27256 Aluminum Connector Block27257 U-Clamp & Nuts27315 Green Status Light27316 Red Status Light27317 Power Light27318 Case Top Cover with Handle 27319 Case Body27320 Case Side Panel27321 Front Handle27322 Top Handle27323 Rear Handle27324 MF-12 Primary Transformer27325 MF-12 Secondary Transformer27326 Weld Potentiometer Knob39110 Test Switch44091 24V Multi-Tap Transformer

ITEM DESCRIPTION ITEM DESCRIPTION MF-12

MF-12

®

MACHINERY DIVISION© 2011 Duro Dyne CorporationPrinted in USA 2/2011BI027404

®