Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: Notesfiles $Revision: 1.6.2.17 $; site uiucdcsb.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxj!houxm!ihnp4!inuxc!pur-ee!uiucdcsb!chaltas From: chaltas@uiucdcsb.UUCP Newsgroups: net.railroad Subject: Re: trucks Message-ID: <11100032@uiucdcsb.UUCP> Date: Fri, 7-Dec-84 22:50:00 EST Article-I.D.: uiucdcsb.11100032 Posted: Fri Dec 7 22:50:00 1984 Date-Received: Tue, 11-Dec-84 03:53:44 EST References: <147@decwrl.UUCP> Lines: 35 Nf-ID: #R:decwrl:-14700:uiucdcsb:11100032:000:1986 Nf-From: uiucdcsb!chaltas Dec 7 21:50:00 1984 hmm...I don't have any firm dates, but here goes, more or less chronologically. Arch bar trucks are no longer found outside of a few relics. They have not been permitted in interchange for many years -- I think they were banned in the 20's. Their frame is fabricated from steel bars -- roughly in an arch, but with straight lines rather than curves. They were prone to failure and had bolts and such that could come loose. Andrews trucks were designed to ease the financial pain of having to junk the arch bar trucks -- they have a cast frame, much like the Bettendorf design, but use the journal boxes removed from arch bar trucks. Bettendorf trucks are what most people think of as a "normal" truck. (This would be much easier with pictures). Arch bar, Andrews, and Bettendorf trucks are all friction bearing trucks -- the journal boxes were packed with oily whatnot. Roller bearings were used in locomotives in the 30's, but didn't become popular for freight car trucks until the fifties. They have much less friction (rather like ball bearing, but capapble of a much heavier load) and are less prone to overheating (a "hotbox"). Timken is a manufacturere of such bearings as was (is?) Symington. Most trucks now in use have exposed axle ends which you can see turning. The Symington (sp?) design did not. I have recently seen coal hoppers on the ICG that have Bettendory-style trucks that have had their friction bearings replaced with roller bearings. The lid is removed from the journal box and you can see the axle turning inside. There was also an archaic truck design by Fox, which was banned even before the arch bar. It had rigid frames and sprung journals. All the above designs have journals rigidly fixed in sprung frames. I'm told that modern trucks have NO fasteners of any kind in them (nothing to work loose), being held together by gravity. This makes them hard to lift, so spares are often bolted together. George Chaltas uiucdcs!chaltas