Soldering in "drop-in Decoders" - what are the downsides?

[nickelplate759]

I was installing a Digitrax DN163K0B into a Kato FP7A today.  I just could NOT get the two motor contact tabs to maintain good contact with the decoder board this time, no matter how much I fiddled with the little grey plastic locking gizmo that pins the contacts down.     I've never really had a problem with this before (I've done several of these, along with Kato E8s and P42 that use a similar board), but this particular install just wouldn't take.   So, I got frustrated and used a little dot of solder to solder the tabs to the board.  It works just fine - but am I asking for trouble down the road?  One downside I can see is that I'll have to remove the board to lubricate the motor at some point.

On a related note, the Digitrax board has too short an LED for the FP7A - so I just unsoldered the Kato factory LED from its board and used it to replace the Digitrax LED.  Fits perfectly now!.

[woodone]

I always solder those , if you every have to remove the decoder it is not too much of a problem- leve them un soldered and you will surely have problems . A no brainer IMO.

[MK]

No problems at all.  Even if you have to remove them later on, just heat up the solder and use a small jeweler's screwdriver and pry up the tabs while the solder is hot.

[jdcolombo]

I still use hard-wired decoders precisely because I simply don't trust "contact"-type electrical transfer that doesn't have some sort of positive engagement (e.g., like a relay where contacts are forced against each other or forced apart).  Hard wire the motor leads.  You'll never regret it - as others have said, unsoldering is a 30-second job IF you ever have to do it.  Which you probably won't - I haven't touched 99% of my hard-wire installs since they were done.

John C.

[Jim Starbuck]

Hard wire the motor leads.  You'll never regret it - as others have said, unsoldering is a 30-second job IF you ever have to do it.  Which you probably won't - I haven't touched 99% of my hard-wire installs since they were done.

John C.

This
My approach is “Build it to run, don’t build it to fail”

I understand the thinking of making things serviceable but I can’t recall removing a hardwired install unless I was scavaging the decoder for another project.

[eja]

I was installing a Digitrax DN163K0B into a Kato FP7A today.  I just could NOT get the two motor contact tabs to maintain good contact with the decoder board this time, no matter how much I fiddled with the little grey plastic locking gizmo that pins the contacts down. 

Funny you should mention this.  I had the very same experience with a Digitrax install in a Kato F40PH yesterday.  I didn't measure, but I suspect the Digtrax board may be thicker than the original.

[mmyers]

I don't try to use the "contact method" anymore on those style decoders. (E, PA, FP, F, etc.) Tin both contacts and the pads on the decoder. Hold the contact down on the pad with a pin and heat the tab until solder flows. Remove heat. A few seconds later remove pin. Done. You can reinsert the grey plastic clip if you want.
I went back and soldered all of my original green box E8's because they were stopping dead after running for some time. I assume as the tabs heat up from use, they may be losing contact? Anyhow, soldering fixed them all.
To remove just heat the tab while lifting it with a jewelers screwdriver. To reinstall after clean and lube, just reverse the process.

Martin Myers

[rrjim1]

I wonder why some people have problems and some don't?  I must have over a hundred locos with a contact type decoder and have yet to have one fail. The only thing I do is apply DeoxIT to the contact area.

[nickelplate759]

I wonder why some people have problems and some don't?  I must have over a hundred locos with a contact type decoder and have yet to have one fail. The only thing I do is apply DeoxIT to the contact area.

I wonder too - even within my own installs.  I've done about 8 of this style decoder without any trouble, but this last one wouldn't work reliably without soldering.
I've decided that I'll leave the previous 8 alone until the day when they refuse to run, and then I'll fix them.

[MK]

I've done about 8 of this style decoder without any trouble, but this last one wouldn't work reliably without soldering.
I've decided that I'll leave the previous 8 alone until the day when they refuse to run, and then I'll fix them.

That's my situation too!  All my F's and E's were fine.  Then my recent F40PH needed to be soldered.  Go figure!

[peteski]

I'm not a fan of this decoder install. I see possible contact reliability issues both with the motor contact strips (held by a flimsy plastic clip) and even with the truck pickup strips contacting against the bottom of the decoder.  I solder mine and therefore eliminate any possible problems in the future.  Yes I usually overengineer things.  That's just how I am.

In my "job" as the local NTRAK club's master-repairmen of locos, I have seen my share of those decoder install failing. Often due to too much Kapton tape applied to the truck pickup strips. I also see the plastic motor lead clips loose and not able to retain the motor contact strips.

Sure, it works well for the original factory light board. That is because in that instance the motor contact strips are in direct contact with the truck pickup strips and are all pinched under the light board. That extra thickness of the metal strips also results in a tighter electrical connection between the light board and the truck pickup strips.  Not the case when a decoder replaces the light board.

[carlso]

I am like Pete. I too solder the motor tabs to decoder plus I also place a piece of decoder wire from the truck pick up strips to the decoder pads. No contact problems at all.

Carl

[nightmare0331]

all of the DCC equipped units Kato kicks out the door of this style (E5/8's, F3/7's, PA/PB's, P42's) have these tabs soldered in place.

It cuts down immensely on contact issues.

Enjoy!

Kelley.
www.dufordmodelworks.com