RFANDPVILLE
Member
What size screw do I need for the middle of a Kadee # 5 to install it? I need to use a screw and need to get a tap and some screws but just not sure of the size. Anyone got any ideas?
What size screw do I need?
- Thread starter RFANDPVILLE
- Start date
PaulB
Member
Kadee has a tap set and nylon screws for use with their couplers. Here's a link to the tap and then the screws:
http://www.kadee.com/htmbord/page246.htm
http://www.kadee.com/htmbord/page256.htm
The tap set includes the appropriate drills for clearence and tapping. There are instructions if you haven't tapped before. I recommend googling it too for tips.
You'll need a small Phillips Head screw driver and a pin vice too. Here's Kadee's pin vice:
http://www.kadee.com/htmbord/page240.htm
Here are some other Kadee tools I hafve which I couldn't mount or repair couplers without:
height gage:
http://www.kadee.com/htmbord/page256.htm
and trip pin pilers (not essential but so much easier when you've got them):
http://www.kadee.com/htmbord/page237.htm
I haven't always used this stuff, though you can't leave home without the hieght gage. It is essential. I have used all sorts of small screws, drills etc to fix coupler boxes in the past. But it is much easier to use the stuff Kadee offers for the purpose I have learn't.
Let us know how you go.
Iron Horseman
Well-Known Member
The standard size is 2-56. The hole size to use for the tap is a #50.
RFANDPVILLE
Member
I have some 2-56 x 1/8 screws and let me tell you they are way to small for fixing couplers with. I can use these to fix the Athearns and I got a tap for that and a pin vise but 1/8 is not going to go all through a Kadee # 5 with a Kadee gear box , they are too small. A bunch of my old stuff is going to have to have the gearbox added on to them. I have the height gauge and the trip pin pliers.
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RFANDPVILLE
Member
Wouldn't 1/4 be about the right size? 1/2 seems too long ?
D&J RailRoad
Professor of HO
Heck, I just super glue a lot of my couplers onto the car.
RFANDPVILLE
Member
I'm finding that the glue just isn't working and that if I break a couple all I need to do is switch it out instead of tear it out.
kenw
5th Generation Texian
sometimes screws just can't be made to work as there is nothing to screw into. super gluing the coupler box to the underframe works well, altho super glue doesn't hold up well under some shock loading. a dab of 5 minute epoxy is much more durable. I've used all 3 methods, none are perfect for every situation.
D&J RailRoad
Professor of HO
If ya use the gell superglue and apply a couple of layers, it holds up to shock. The Kadees hold up well to sever coupling but wont handle dives to the floor.
NScaler
Engineer in Training
I have been a machinist for the better half of my life. A #2-56 thread isn't going to thread well into anything freehand. Just putting a #2-56 tap into a pin vise is only going to bore a slip-fit hole into whatever it is you are tapping. If you manage to get a couple threads to be perfect you got lucky. Thread spacing on a #2-56 is only .0178".
So try using a tap guide next time...
Get a piece of 3/8" thick aluminum, plastic, or hardwood. Drill a .086" hole through (#44 drill). Make sure this hole goes through as square as possible. Use a drill press if you have one. Slide the tap through and line it up with the hole in your work piece. Press this piece firmly to your work and tap the hole.
Here is the tap guide...
Not all taps are alike either. There are plug taps, made for tapping all the way through a piece. Then there are bottoming taps made to tap to the bottom of a blind hole that does not go all the way through the piece. There are also cut taps which "cut" the thread into the part, and form taps that actually "form" the thread. These form taps don't cut any material away. Rather they press the threads into the material. These would be absolutely idea for working with woods, plastics, soft metals, etc. They make a stronger thread. You can pick these up at www.mscdirect.com. Here would be a good choice... http://www.mscdirect.com/product/49710379 Yes, these are pricey, but well worth it. It will last forever for modeling work.
NOTE: You use a smaller drill size for form taps. For a #2-56 you would use 5/64" or .0781". For softer materials I might even go the next size smaller.
Hope this helps.
So try using a tap guide next time...
Get a piece of 3/8" thick aluminum, plastic, or hardwood. Drill a .086" hole through (#44 drill). Make sure this hole goes through as square as possible. Use a drill press if you have one. Slide the tap through and line it up with the hole in your work piece. Press this piece firmly to your work and tap the hole.
Here is the tap guide...
Not all taps are alike either. There are plug taps, made for tapping all the way through a piece. Then there are bottoming taps made to tap to the bottom of a blind hole that does not go all the way through the piece. There are also cut taps which "cut" the thread into the part, and form taps that actually "form" the thread. These form taps don't cut any material away. Rather they press the threads into the material. These would be absolutely idea for working with woods, plastics, soft metals, etc. They make a stronger thread. You can pick these up at www.mscdirect.com. Here would be a good choice... http://www.mscdirect.com/product/49710379 Yes, these are pricey, but well worth it. It will last forever for modeling work.
NOTE: You use a smaller drill size for form taps. For a #2-56 you would use 5/64" or .0781". For softer materials I might even go the next size smaller.
Hope this helps.
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IowaFarmBoy
Member
I have 2-56 screws in lengths from 1/8" up to 1" long that I got in lots of 25 to 100 off ebay. For coupler boxes I normally use 3/16" or 1/4" I also use 2-56 screws in tapped holes to hold trucks. If possible I replace any self-tapping sheet metal type screws with 2-56 in appropriate lengths. I have a cheapie accessory chuck that fits my Black and Decker cordless screwdriver and chuck a tap in that. I lube the tap with beeswax and have not broken any 2-56 taps, Kadee or generic, when using this system. I have not tried any other tap sizes.
RFANDPVILLE
Member
I have some older Bachmann units mostly box cars , hoppers and refers and especially cabooses ( I have this thing for cabooses) that have a really large bolster on the bottom for the trucks. The wheels snapped in on the bottom and I am having troubles trying to even size those up. I believe that they would be good running units with a little work. It's just the hole that these snapped in to is to big. I tried to put some putty in them and re drill them but that didn't work. I was thinking maybe here is a good spot for epoxy but I don't know if epoxy can be drilled? Never used epoxy before. The putty can't though they said it could. It just turns into a mess.
D&J RailRoad
Professor of HO
Yeah Mike. JB Weld would work there. I have some out here that you can use next time ya come out to run trains.
RFANDPVILLE
Member
The local Hobbytown here in Fredericksburg has some JB Weld too. I don't know enough about it to do anything with it, but these units I want to make run again and would be happy to explore all possibilities.
Most HO cars use 2-56 1/4" screws to hold couplers on the car. Get mine from McMaster-Carr: http://www.mcmaster.com/#machine-screws/=q6fv7e
You can buy them in boxes of 100 for $5.67. Guess the price has really gone up as last box cost around $3.50. But if you look around there you might find some cheaper. Like flat head screws because if you countersink them, there's no head sticking up. Guessing you'd pay the same price at your LHS but only get 10-12 screws.
You can have them shipped to you or if you're close enough, pick them up will call. If you also get other screws, drills, taps & other tools, will make the shipping worth it. Theiry shipping by UPS has only cost me $4.50 before.
You can buy them in boxes of 100 for $5.67. Guess the price has really gone up as last box cost around $3.50. But if you look around there you might find some cheaper. Like flat head screws because if you countersink them, there's no head sticking up. Guessing you'd pay the same price at your LHS but only get 10-12 screws.
You can have them shipped to you or if you're close enough, pick them up will call. If you also get other screws, drills, taps & other tools, will make the shipping worth it. Theiry shipping by UPS has only cost me $4.50 before.
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Cjcrescent
Master Mechanic
There should be a way to "fill in these extra large holes using 2 sizes of styrene tubing, fitting a smaller size into a larger. Unfortunately, I don't remember what sizes, but if your LHS has an Evergreen rack, you could take a car with you and see which two sizes would do it. I've done it in the past on a couple of cars given to me as gifts and all you need are the 2 sizes of tubing, some styrene cement, and a 2-56 tap to put threads on the smaller tubing.
As for the epoxy, the only problem in filling in the holes with it, is locating the proper centers for the screws. If you get these a little off, the car may not track correctly. The couplers could also be off enough to hinder good operation. All in all, I'd try the tubing first.
