I have two GP 38’s I recently installed DCC and now Im working out installing Kadee couplers. Anyone done this? Seems quirky to install the coupler directly to the frame and mount the box on top of it. Just doesn’t seem right. Plus the screws seem way to long. Do I cut them?
Any comments.
I’ve done a few old Athearn BB engines from the 1960’s. I found that I had to grind down the frame to get a good place to mount the couplers, because the heights were way out from where I wanted them.
Since the frames were metal and part of the electrical circuit on these engines, it’s important to make sure the coupler shanks are insulated from the frame. Kadee couplers are all-metal, and will conduct electricity. If you have two engines with oppositely-polarized frames and the couplers are “hot,” you’re going to have a dead short if they should ever touch.
To make sure this doesn’t happen, I use the Kadee “draft gear boxes” which are simply plastic housings complete with a centerpost for the coupler. The centerpost is a plastic sleeve, with a hole for the mounting screw. By using these boxes, you guarantee that the coupler is isolated from the frame and won’t cause a short. Draft gear boxes are dirt cheap, by the way.
The mounting screw may be cut to length.
Draft gear boxes? Do you have a Kadee part number?
i dunno the part number but you get them usualy when you buy the number 5 couplers. Well in the 2 pair packs that is. In the bluk packs they dont have draft gear boxes. I do know you can buy them seperatly… but dont know the part number
~matt
Do you have buddys that are into model railroading? ask them if they have any spare draft gear box’s,we always have a few in our toolbox’s!
Ahh thats what your talking about. I have lots of those. So you put the coupler in the box and screw thru it etc???
To mount #5s in their draft gear boxes on the GP-38s, you’re going to have to drill out the hole and then tap it for a #2/56 screw. You can get the Kadee drill and tap kit from your LHS.
As an alternative you can break off the frame mounting pad with a pair of pliers and then build up a new mounting pad on the body behind the pilot with styrene, drill a screw hole and use a self-tapping screw. (Before you break off the old pad, use it to mark off where the bottom of the coupler will be on the pilot, then subtract the thickness of the draft gear box and that’s height or thickness of the new mounting pad). This method will allow you to permanently fill the opening below the coupler. With the frame mount you have to attach the coupler first as you have to screw it in from above and then attach the body.
Ok I alreadyhave them both drilled and tapped. I just need to remove the current setup Kadee #37’s and install the plastic gear boxes instead.
Thanks guys!
I have an Athern BB that I installed Kadee’s on. I installed them with the same plastic piece that came with the engine. That was on the advice of an expierenced club member and I’ve never had a problem.
Also, didn’t the BB GP38-2’s require Kadee couplers with overset shanks if you are going to frame-mount? It’s been a while since I did a Kadee mount job on one of those, but I fuzzily remember a standard #5 coupler would sit a bit too high with the BB GP frame.
When I mounted #5 Kadees on my SD40-2’s, I filed the coupler mounting pads about 1/16" or so, and kept checking to see when I had filed enough. I drilled and tapped for a #2-56 screw, used the plastic screws that came with the #5 couplers, and cut to length when finished.
Brad
Confusion reigns:
Old Athearn BB engines had a flat mounting pad you could drill and tap a 2-56 screw for.
You had to then buy 2-56 screws. Brass 3/8’ comes to mind. Walthers sells.
ALL Athearn chassis’ are low - even with 42" wheels. A #7,27,37, OR 47, was Kadee’s answer. a thin dab of Contact Cement or Walthers ‘GOO’ on the pad keeps the coupler centered straight ahead…
ALL Kadee couplers come with draft gear / coupler mounting boxes (except #4) or bulk packs, that insulates the coupler from the Athearn chassis.
jflessne #37’s ARE insulated couplers with plastic draft gear boxes… WHY are you changing? If you want shorter, go with #44’s (or #34’s), longer #41. All come with insulated boxes…
Long island tom: You want the ‘Underset shank’ not ‘Overset’.
To those recommending #5’s, they’ll be low without chassis modification.
For best appearance, cut off the Athearn frame extension, build up a mounting pad with styrene to the correct hieght on the shell, mount a Kadee draft gear box, then fill in the pilot with sheet styrene. This also solves the insulation issue.
See the response in this thread with picture by Bob Boudreau http://www.trains.com/community/forum/topic.asp?TOPIC_ID=63050
the lat BB i done i used number 27 but I found they too short. so I’m going to get some 21 they are longer. I find the BB atherns nee a underset shank type coupler. I find the #5 too low.
If you are going to run engines together permanently I make the whole job a lot easier by using a drawbar between the engines. I shape it roughly like a pair of couplers and paint it black. That way I can close couple them where I want, have no unwanted uncoupling and save money. Nobody has ever noticed them either. You can also use the existing coupler pocket on the engines.
I agree with Don Gibson.
I driil a #50 hole behind the original coupler mounting hole, than tap with 2-56, then cut the front of the mounting pad so it won’t stick out from the pilot and allow the coupler box to go back far enough. Usually it will take an under shank (knuckle above the shank) coupler to gauge properly. DON’T CUT THE FRAME.
The plastic draft gear boxes are availablie separately:
This is definitely the best solution to putting KD couplers on an old athearn BB loco.
Please follow the following URL to Kadee for mounting recommendations that apply to all brands of equipment.
http://www.kadee.com/conv/ho.htm
WHY are you using 20’s when 40’s do the job for less money?
If a #47 is too short, go with #41. You must have super tight curves.