In a message dated 09/06/2006, gpayton880@....... writes: Does anyone have any GOOD photos of a completed Lehmann Sensor? I have a scale drawing if that would be any use? I use two 1/4" thick bright mild steel plates, 2" wide by 3.5" long. They are held apart by 3 or 4 zinc plated 3" mild steel set screws with three nuts each. On the centre inside of both plates I fit two 1" square by 1/8" thick NdFeB square magnets to give an arrangement -> Bolt Bolt XXXXXXXXXXXXXXXXXXXXXXX Backing plate NNNNSSSS <-- Coil --> SSSSNNNN XXXXXXXXXXXXXXXXXXXXXXX Backing plate Bolt Bolt I find that this works very well and it is easy to adjust. The coil that I use came as a spare for a 220V water valve on a washing machine and it is about 3/8" thick by slightly over 1" OD, about 5,000 turns. I use the same layout but with 1"x1/2"x1/4" NdFeB magnets for the 1/16" Cu damping plate. Any internal field inbalance is shorted through the bolts and the external field is near zero. Hope that this helps. Regards, Chris ChapmanIn a message dated 09/06/2006, gpayton880@....... writes:<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>Does=20 anyone have any GOOD photos of a completed Lehmann=20 Sensor?I have a scale drawing if that would be any=20 use?I use two 1/4" thick bright mild steel pla= tes,=20 2" wide by 3.5" long. They are held apart by 3 or 4 zinc plated 3" mild stee= l=20 set screws with three nuts each. On the centre inside of both plates I fit t= wo=20 1" square by 1/8" thick NdFeB square magnets to give an arrangement ->Bolt &= nbsp;  = ; BoltXXXXXXXXXXXXXXXXXXXXXXX Backing plateNNNNS= SSS = ;<--=20 Coil -->SSSSN= NNNXXXXXXXXXXXXXXXXXXXXXXX Backing plateBolt &= nbsp;  = ; BoltI find that this works very well and it is easy= to=20 adjust. The coil that I use came as a spare for a 220V water valve on a wash= ing=20 machine and it is about 3/8" thick by slightly over 1" OD, about 5,000=20 turns.I use the same layout but with 1"x1/2"x1/4" NdF= eB=20 magnets for the 1/16" Cu damping plate.Any internal field inbalance is shorted through= the=20 bolts and the external field is near zero.Hope that this helps.Regards,Chris Chapman[ Top ] [ Back ] [ Home Page ]