I like to use screws to attach KD couplers. To avoid having the screw head show I use 1-72 flathead screws. If you countersink the screw slightly into the coupler box the head will not show under the car.
I will sometimes put a small amount of glue between the coupler box and the car floor to prevent the coupler box from rotating around the screw.
Mark Vinski
Kadee posts a what-fits-what list that lists every piece of rolling stock manufactured over the last 50 years. They make more variations of their coupler than I can remember. Long shank, medium shank, short shank,head offset up, head no offset, head offset down, all plastic, whisker spring, and dark of the moon. A #5 Kadee works on most freight cars. There is a whisker spring version of the #5 but I haven't used it, I am still buying 10 packs of #5s. For locomotives and passenger equipment it is worth checking the what-fits-what list. You want insulated couplers for locomotives, either plastic coupler or all plastic mounting of the coupler box. You can glue the boxes in place, but should you ever need to replace the coupler, you will wish you had used screws. 2-56 screws are right to secure coupler boxes and lids. A lot of cars, all the blue box Athearn cars, need a washer under the trucks to get the coupler up to proper height. #6 flat washers from the hardware store work just fine. You need to buy or make a height gauge. I made mine from a block of pine. The NMRA gauge has a notch in it for coupler height that I used to get my home made gauge right. For what you are doing, converting from truck mount to body mount, the what-fits-what list won't help you, it will list a replacement for the truck mount coupler, which isn't what you want. Just use a #5. Cut off the truck mountings, or turn the trucks around to get it out of the way. Fasten the stock Kadee boxes to the car floor. I just eyeball the center of the car and it works, looks right, and the couplers couple when banged together. Install a coupler and check the height. If the coupler is low put a washer under the trucks. If the coupler is high, put a shim under the coupler box.
David Starr www.newsnorthwoods.blogspot.com
1arfarf33.How to center gear boxes on car body as I'll be cutting off plastic couplers from trucks?
I just eye ball it. I guess I could measure it in millimeters and divide it in half but I think my eyes get it close enough to center that I've never had any problems with them on the two dozen Tyco cars I have converted from truck mounted couplers to body mounted couplers.
1arfarf34. What adhesive to glue on gear boxes if they are not screwed on?
I use super glue (CA), Medium Zap a Gap to be exact. Super glue isn't as super as they say. It is strong enough to hold on the coupler boxes but if you really want to remove the box it isn't that hard to do and it won't damage your models like Testors airplane type glue which melts the plastic together.
By using glue you will be able to adjust the box to the best position before the glue dries. If you use a screw where ever you put the hole is where it has to go.
I'm sure others here will advise you not to use glue but I've never had any problems with it and I've been doing it that way since the 1990s.
1arfarf35. How to determine correct coupler before installing gear box?
Kadee #5 comes with the box so use them.
1arfarf36. Any other item(s) needed to correctly install couplers.
You will need to make some plastic shims which need to go between the car body and the coupler box so the couplers are the correct height. You can make them out of Evergreen sheet styrene. Before you cut the old couplers off of the trucks slide a shim in there to check the thickness needed. 0.040" or 0.060" is a good guess. Make the shim the same size as the coupler box.
1arfarf3Any other info, tips, tricks, etc greatly appreciated for a new endeavor.
Try one car first before you do all the rest and see how it works for you.
BigDaddy tstage Do you mean the draft gear cover, Henry? Maybe not. I've been know to glue the draft gear cover onto the chassis. I'm not sure I have an explanation for that. One downside is that if the cover sticks out beyond the floor and the the chassis is in a box with other stuff while the shell is being weathered, it is prone to breakage. I will suggest to the OP that he make sure that any coupler box screw will clear the steel weight, or cut or drill the weight to provide clearance for that screw.
tstage Do you mean the draft gear cover, Henry?
Maybe not.
I've been know to glue the draft gear cover onto the chassis. I'm not sure I have an explanation for that. One downside is that if the cover sticks out beyond the floor and the the chassis is in a box with other stuff while the shell is being weathered, it is prone to breakage.
I will suggest to the OP that he make sure that any coupler box screw will clear the steel weight, or cut or drill the weight to provide clearance for that screw.
Deano
BigDaddyI've been know to glue the draft gear cover onto the chassis. I'm not sure I have an explanation for that. One downside is that if the cover sticks out beyond the floor and the the chassis is in a box with other stuff while the shell is being weathered, it is prone to breakage.
Yea, I never glue a draft gear cover and always use a screw. If a draft gear spring ever goes wonky (and I've had a few do that over the years)...or the coupler is acting strange, all I have to do is unscrew the cover and replace and/or fix the offending piece. Gluing makes that much more difficult.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
tstageDo you mean the draft gear cover, Henry?
Henry
COB Potomac & Northern
Shenandoah Valley
BigDaddyThe box I screw on, 2-56 like everyone else. You can find these cheap enough and in black on Ebay
Do you mean the draft gear cover, Henry?
These days, I do glue the top half to the chassis with ACC. The box I screw on, 2-56 like everyone else. You can find these cheap enough and in black on Ebay
The Kadee website has useful information here:
https://www.kadee.com/htmbord/helpful.htm
Kadee itself makes 2-56 screws out of nylon that I have used. But unlike metal screws they tend NOT to be self tapping. I seem to recall they offered nylon nuts that matched. They also offer metal screws but many others do as well
They also make a 2-56 drill and tap set
https://www.walthers.com/2-56-tap-drill-set-includes-tap-and-50-43-drills
Dave Nelson
Kevin posts some good information. I've found, however, if you are drilling into softer plastics, tapping the hole is unnecessary. The 2-56 screw is MUCH harder than the styrene undercarriage and will actually self-tap the hole with its own threads. For harder materials (e.g. Delrin or metal), I would choose to tap the hole.
To find the center, measure across the floor and divide by 2. I use a dial caliper that measures in 0.001" to make the job quick. I set the coupler screw in 0.100" from the floor end.
.
Use 2-56 screws and only install them in a pre-threaded hole. Use a #50 drill to make the hole.
In house cars, like boxcars, you can use longer screws. Tank cars and hoppers require shorter screws. I use 3/16" screws on these cars. Flat cars require a 1/8" screw and a plug (bottoming) tap to prepare the hole.
It helps to add material inside the car to give the threads more material to bite into.
Give it a try, post pictures, and ask more questions.
-Kevin
Living the dream.
I can touch on a couple of your questions:
That's pretty simple, measure the width, divide by 2 ? and by using the Kadee coupler height gauge.
Once again, the coupler height gauge. The back side of the gauge gives you the correct height to mount the box, that way you'll know if any extra shimming is needed.
The business end of the gauge gives you the correct coupler placement, height, and will also help you center the box and coupler on the car.
Mike.
My You Tube
Need info on installing kadees.
1.Have centering springs, 232 & 242 gear boxes, a few #5's, and a few Whiskers.
2. What size, length, and material for screws, washers?
3.How to center gear boxes on car body as I'll be cutting off plastic couplers from trucks?
4. What adhesive to glue on gear boxes if they are not screwed on?
5. How to determine correct coupler before installing gear box?
6. Any other item(s) needed to correctly install couplers.
Any other info, tips, tricks, etc greatly appreciated for a new endeavor.
Thanks