POTENTIAL CONFLICT IN TFC PATTERN PROC.

Narrative

MYSELF AND MY STUDENT WERE ON DOWNWIND LEG ABEAM THE NUMBERS AT FORT WORTH SPINKS ARPT (FWS); WHEN I ANNOUNCED INTENTIONS TO SIMULATE AN ENG FAILURE RESULTING IN A FULL STOP LNDG. UPON SIMULATING ENG FAILURE WE BOTH CHKED FOR TFC AND COMMENCED A SHORT APCH UPON SIGHTING NO TFC. AT XA00 LCL; FWS CTAF FREQ CHANGED; A NOTAM TO WHICH I WAS UNAWARE. ALL NORMAL RADIO PROCS WERE FOLLOWED WITHIN 5 NM OF THE ARPT. HOWEVER; OUR TFC PATTERN TO RWY 35L WAS FLOWN CONTRARY TO TYPICAL STANDARD R TFC PATTERN. OUR RADIO CALLS WERE NOT HEARD BY FWS TFC; RESULTING IN THE TWIN ENG ACFT GOING AROUND. NEITHER I NOR MY STUDENT EVER SAW THE TWIN ENG TFC UNTIL WE PARKED ON THE RAMP. A BYSTANDER NOTED THE SIT WHICH HAD JUST OCCURRED AND POINTED OUT THE TFC WE HAD CUT OFF. THE TFC WAS JUST TURNING XWIND LEG OF THE TFC PATTERN. BASED ON THIS; OUR SEPARATION COULD NOT HAVE BEEN CLOSER THAN 1-2 NM. I ATTEMPTED TO SPEAK WITH THE PLT OF THE ACFT; WHO WAS ALSO A FULL STOP; BUT HE TAXIED TO HIS HANGAR. I BELIEVE THIS SIT COULD HAVE BEEN AVOIDED BY THOROUGHLY CHKING ALL NOTAMS -- EVEN FOR A LCL FLT. I ALWAYS FLY PUBLISHED ARPT TFC PATTERNS; AND TEACH MY STUDENTS THE SAME; BUT IN THIS SIT I DO NOT BELIEVE THAT FLYING A NONSTANDARD TFC CONTRIBUTED TO THE SEPARATION OF ACFT.