FRUSTRATION with MT screws for attaching body mount couplers

[daniel_leavitt2000]

So we're not phrasing???

Just  the tip.

[mmagliaro]

+1 on the brass screws from microfasteners.com (or anywhere else).
They have much deeper, cleaner threads than the MT screws, and the heads are much
better.  I usually use the round-head ones.  But if space is tight and there's an axle going over the top of
the screw, then I use the flat-head countersunk ones and I use a ball reamer to make a countersink depression
in the coupler box so the screw lies down flat in it.

But yes... even so, always tap the hole.  It's just so much easier.

[nkalanaga]

I also use flathead screws on my 1025s, countersinking the box with a 3/32 drill bit twirled by hand.  You don't want it to dig in, just scrape the plastic away.

Those old zinc screws were worse than useless.  In many cases the parting line was thick enough that the screw wouldn't go into a tapped hole, if they jammed they usually broke, and if you did get them in, they'd break if you tried to remove them.  I had to take one out of plastic last week, and it came out in pieces, ruining the hole in the process.  Being plastic, it wasn't hard to plug and redrill, but if it had been a metal underframe I might still be arguing with it.

Their original zinc screws, the black ones, weren't bad, back in the 70s.  They were nicely cast, went in smoothly, and lasted well.  They also made good drain valves for tank cars if one filled the slot after installing them.

[Lemosteam]

Did anyone mention tap the hole? 

I like these nylon screws, very durable and won't strip plastic threads and are VERY easy to cut to length:
http://www.microfasteners.com/nbb00908-00-90-x-1-2-binder-head-screws-nylon.html

[jdcolombo]

Those old zinc screws were worse than useless. 

The zinc screws were why I decided to go with the 3/16" brass flat heads.  They were awful.  The newer screws are much better, but I still like the flatheads, which seem to have a better slot for a screwdriver and which also will fit flush in a 1015 coupler box if need be. 

Oh . . . and yes, tap the hole 

John C.

[carlso]

How about tap the keg.

C

[Kisatchie]

How about tap the keg.

Mmmm... beer...

[djconway]

As others have said:
   1 - buy a 00-90 tap, and tap the hole 
   2 - buy 1 tap drill  #62  0.038"
   3 - buy 1 clearance drill #56 0.047"
   4 - use the "newer" 00-90 stainless steel screws from Micro Trains or order in lots of 100 (www.boltdepot.com)

also make templates for locating the hole - just a little bit off will hurt the operation of the MT Couplers (don't ask how I know this )

[milw156]

I love these MTL screws, and, yes, I use a tap.  Off topic, but I also use these screws for trailer kingpins to fit the hitches in my TOFC cars!

DFF

+1

[Mike C]

 Seems like the guys here like to tap the hole .....

[thomasjmdavis]

or order in lots of 100 (www.boltdepot.com)

DJ-
I looked all over that site and couldn't find anything listed smaller than a 2-56.  Is there a trick to finding 00-90s?

[mmagliaro]

DJ-
I looked all over that site and couldn't find anything listed smaller than a 2-56.  Is there a trick to finding 00-90s?

Me either.

But these guys have them: 
https://www.microfasteners.com

Also here:
http://www.fastener-express.com/00-90-x-12-round-slotted-machine-screws-brass-stainless-qty-50.aspx

Heck, even Micro-Mark has them, but they are a little more expensive there
http://www.micromark.com/round-head-machine-screws-00-90-x-1and2-inch-pkg-of-25,10664.html
(25 for 11 bucks, about 55 cents a piece)

[rschaffter]

You gotta tap it, Daddy-o...

[randgust]

I buy mine in bulk for my kits.  Buying by the gross really saves some serious money if you use them the way I do:

http://www.morris01550.com/

And yes, always tap the hole....

[djconway]

DJ-
I looked all over that site and couldn't find anything listed smaller than a 2-56.  Is there a trick to finding 00-90s?

Sorry folks -- Going to have to check my stock when I get home -- I'm 99% sure that's where I ordered them, but that was a few years ago .