Is there a standard size screw that Lionel has used to attach shells to frames?

Well, "standard" is really not happening, they have been used in various lengths, and if you miss the length by too big a margin, you either have the shell fall off or you crack the posts.  Most of these look to be #4 sheet metal screws, so I'd just order several sizes from around 1/2" to 3/4 or even 1" and have the right one on hand.

Thanks John.  They look like #4 sheet metal screws to me as well.  I have lots of these, but none are self tapping. I guess I'd better go to Lowes (the biggest rip-off hardware in history) and look for some self tap.

@Mannyrock posted:

Thanks John.  They look like #4 sheet metal screws to me as well.  I have lots of these, but none are self tapping. I guess I'd better go to Lowes (the biggest rip-off hardware in history) and look for some self tap.

If the holes are already there, there's no need for the self tapping part.

In the Greenberg LIONEL Repair Manual book that I have (which reproduces LIONEL's service docs), the screw at the front of an F-3 A unit cab is secured to the frame using a #4 x 1/2" sheet metal screw.  I bought several recently and they worked fine--no need for self-tapping.

Thanks, I'll try the regular #4 then.

You could get a bunch of different ones from Jeff Kane @ the train tender or Len caperelli (sp) who bought the Ted nygeres screw business.  Also bill Harrison at S&w .

Btw over 90% of the cost of screws at big box stores comes from the packaging, handling, shelf space cost and overhead.  Buy their screws at 5lb of one size and the cost comes way down.

I sold some parts with my trains at shows but screws and nuts were totally unprofitable.   Selling figures, lanterns, xfmr handles, bulbs were okay but i eventually stopped that as well.

If you ever get to York,  stop and see Jeff and Len in the Orange hall.  Just get a bunch of stuff you may never need but good to have if you are delving into postwar and MPC stuff