I’m currently in the process of installing DCC in two HOn3 brass locomotives, and I’m having a rather unusual problem. Both locos currently require a large starting voltage to get moving on DCC, despite the fact that their motors (Mashima) run with perfect slow-speed motion when tested on DC. I currently have the decoder pickup wires soldered directly to the tender chassis, and I suspect that this may be the problem. Would putting a screw into the chassis, then soldering the wire to the screw, help with this issue?
If you cleaned the tender floor and used resin core solder or a resin solder flux that should not be your problem. Adjusting CV2 to a higher value will give the motor more voltage at speed step 1.
It would also help if you tell us which brand and type of decoder you’re installing, because some of them have a “kick start” voltage and duration CVs that can be adjusted along with CV 2.
I’ve got it sorted. After re-soldering all the connections and making sure they were solid (thanks, Randy), I discovered that the tender pickup scheme on the C-16, while fine for DC, didn’t pull its weight when carrying a DCC signal. Soldering the tender trucks directly to the decoder fixed the problem.
As for the C-18, well, the cause of that loco’s problems became apparent when one of the tender truck sideframes disintegrated in my hands from metal fatigue. Seems the previous owner used it a lot.
That was a common problem with some manufacturers, who used inferior brass.
Several years ago a woman brought a brass steam engine to the club that she was wanting to sell.
Her father had bought it when he was with the U.S. Army occupation forces in Japan sometime in the late 1940’s or early 1950’s. I don’t remember what brand name it was; a green box with black foam padding. The foam had disintegrated and was stuck to the model. Many small parts had fallen off due to poor soldering, and the boiler seams were separating because of the inferior solder.