Found an older production Athearn GP38-2 today price: $55.99. INRD 3805. Great detail on the shell, but: Not DCC ready. here are some photos:
Any hints on this one? I know that the motor must be isolated from the frame; but do I need plastic screws? Also, Im not putting a Keep-Alive in this one.
Sort of helpful, not really the route im taking, but close.
Can’t get the DH123AT anymore, but all it is is a regular decoder with wires already soldered to a set of Athearn motor clips. So all you need to do is solder the appropriate wire to the top and bottom motor clips (swap the top clip for the bottom one - the bottom one has an extra finger to contact the chassis, by swapping them, you avoid having it wear through the layer or two of tape you need to put there). Be careful - wtih both clips off, the motor literally falls apart. You need a wire between the two vertical tabs on each truck, and that wire goes to the red decoder wire. The black wire, those harnesses clipped to the light bracket in front but those are usually loosely riveted and make poor contact. Drill a hole in the frame and run in a brass screw and solder to that. These aren’t that difficult to convert. Adding the factory board so you can then plug the decoder in is a waste of money buying the factory board - it still has to be soldered to the pickups and motor!
–Randy
Jst Connector board is installed, and the shell doesnt go back on…[banghead], should have known this would happen. Popped out the weight under the dynamic brake bulge. Dont think I want the decoder touching the shell. Thoughts?
Yeah there is no way to fit the decoder and the factory board in without modifying the shell, which I am not doing. Good idea with switching the motor contacts.
Sorry - I failed to note you got one of the Athearn adapter boards. Didn’t realize they sell for that much ! I have a whole drawer full as that’s the first thing I remove when installing DCC, mainly because I don’t use 1.5 volt bulbs and I’ve had limited success trying to convert the board.
For Athearn conversions, I prefer to use a TCS A4X decoder (Atlas style board) and just silicone it to the top of the motor. Low profile and easy to wire.
As an additional step, I like to solder wires to the metal plates on both sides of the trucks for track connections to the decoder. Prevents on having to rely on a common ground connection through the chassis.
Mark.
Took multiple photographs of the assembly process, will upload in morning.
TCS seems to have a similar install. GP38-2 non DCC ready.
http://www.tcsdcc.com/Customer_Content/Installation_Pictures/HO_Scale/HO_Search/search.html
Rich
Yes, I found that. Its pretty much what I ended up doing. The Athearn drop in board didnt fit, so I took it off and hard wired the decoder in. Put it on the track last night. I determined that I had a couple of issues to resolve, mainly with lighting, photos will be delayed a few hours.
The frame receives power from the left hand rail. The motor must be isolated from the frame. Addionally on the advice of Randy, I swapped the motor clips from the top to the bottom, to prevent the tabs from wearing through the tape and short circuiting the decoder. As warned the commutator brushes fell out when I removed the clips, be careful to re-insert them so that the curved worn side matches the commutator or you will be replacing them prematurely.
For the Left rail pickup, I soldered it ot the tab coming up for the light bulb. The tab on this locomotive was not loose so I didnt bother with drilling and tapping a hole in the frame, your experiance may vary.
Motor and flywheel assembly with tabbed clip still on bottom, as previously mentioned this clip was swapped to the top. Heed the warning about the little springs and commutator brushes.
Chassis reassembled with the Athearn Drop in board. It did not fit under the shell of the GP38-2. I decided to hard wire vice risking damage to the shell.
Ooh, I’m not the only one who uses a nice (good bit) amount of black tape in my Athearn units… Nice job! (And, nice to see someone else likes the tape thing!) Very nice how-to presentation here.
I would caustion on the use of black electrical tape - over time it gets gooey and oozes adhesive, and comes loose. It;s probbaly ok to use a layer or two in the chassis well to isolate the motor, since it will be effectively clamped in place by the motor, but I never use it in any of my installs. Besides the gooey mess and the tendency to come unstuck, it’s also significantly thicker than the recommened alternative, Kapton tape. For holding down wires to keep them out of the way of the shell or moving parts, it can’t be beat. It also resist wearing through better than plastic electrical tape, but it’s not indestructible, which is why I suggested changing the top and bottom motor clips.
–Randy
I did a similar conversion a few years ago with a HO Walther’s H12-44. Had to isolate the motor but used Kapton tape. Thin and quite tough. Bottom frame is one rail, the top weight is the other rail. Motor halves are separated by a piece of plastic. Both brushes firmly connected to each motor half.
Just had to make sure the mounting holes in each weight were smooth so as to not puncture the Kapton tape. Nylon screws hold the motor in place.
Rich
I will give Kapton tape a try when I get some. Have an additional question, I have now noticed that the entire locomotive leans a couple of degrees to the left when at rest. What causes this and is it fixable?
Hard to tell from the picture, but if you have your decoder wrapped in black tape, I suggest removing it. Black electrical tape acts as an insulator and the decoder needs to breathe as it does get warm. Kapton tape is designed to not hinder heat disipation.
As for the lean, that problem is caused by the king pin tab on the top of the truck not being perfectly level. Pry it up or down to level things up.
Mark.
I did a tutorial once on how to do these properly…perhaps a search would have given the OP insite to what shortcuts shouldn’t have been taken?
Removed black tape from top of decoder. Left it on bottom to prevent shorts. Is the king pin tab the metal one or the tabs on the gearbox?
And I did in-fact do a google search, and your thread didnt pop up in the top ten responses.
I also did a google search for Kapton tape. It looks a lot like the brittle cracked stuff i pulled out another old locomotive, dont remember what it was or how old. Does Kapton tape dry out over time?
The king pin tab is the metal one with the hole in it that fits over the pin on the chassis. Set the truck on a flat surface and rest a straight edge on the metal tab. You’ll easily see which way it has to be bent to be level.
Mark.
I took photos of the trucks/chassis. Please enlighten me as to were this king pin is because I am sure that it is looking at me but I am not understanding your description.
