Caboose trucks GN


aaejj2j
 

I have posted four prototype photos and one model photo of an Andrews truck as used on the shorter GN cabooses in the Photos section in a new file called GN Caboose Trucks. Of interest here is the spring chamber area. I am interested in information or thoughts on the approach the GN used on these caboose trucks. The GN had similar caboose trucks with "Bettendorf" T-section and perhaps U-section sideframes which utilized the same or nearly the same spring chamber. About up to 1940 the GN cabooses generally used archbar trucks but these 25' wood cabooses were upgraded about in the 1940s and received new trucks, generally Andrews and Bettendorf T-section sideframes. The 1945 and later 30' cabooses like the Ambroid, Northeastern, and PFM Tenshodo models had U-section sideframes with similar spring chambers. I wonder if this approach was unique to the GN or if others had similar trucks. The trucks have a 5-0 or so wheel base and probably came off older freight cars which might have gotten newer trucks of higher load capability. The spring chamber appears to have been flame cut (on the ends) out of a box section of steel. The bolster is seen farther inward.
I photographed this on a car on private property in MT along US 2 and the old GN tracks; but from photos I have seen it is representative. Some older photos may show a sheet metal over the area above the springs. Note I added a plastic foot long ruler to help me determine various lengths.
Of course what I have been trying to do is improve the trucks on my cabooses as I do not like the brass trucks for operation and no plastic framed trucks look correct. Most model trucks are longer wheelbased and if they have real springs their spring chamber seems unrealistically wide. Trucks such as CV or Kadee are often modified with the old Walthers, Silver Streak, Kemtron (I think I have all of these) metal springs result in the springs protruding too far outward, visible bolster end, and too wide a spring opening and without the appropriate enclosure. I have modified some model trucks as IM. I have many more photos and some with dimensions added and some of various model trucks and conversions for those who may be willing or interested.
Thank you,
Tyrone Johnsen
Rockford, IL


brianleppert@att.net
 

This is in response to Tyrone Johnsen's post from eight days ago:

These are Swing-Motion Caboose trucks. Swing-motion trucks differ from conventional trucks in that the truck bolster and spring plank never touch the side frames. Rather, a Transom connects the two side frames. The transom is open in the center from the top thru the bottom. The spring plank hangs from the transom by four links. The springs sit on the spring plank and the truck bolster sits on the springs.

I have added three illustrations from a Bettendorf Co. brochure to the "GN Caboose Trucks" file on the Photos section. These show Bettendorf's Swing-Motion Caboose Truck, their cast Transom and a cross section view which I hope will better explain how these trucks are set up.

Notice that the center line of the leaf springs are inboard of the side frames. This is why less of the leaf springs are visible from trackside.

The transoms on GN's cabooses are kind of crude looking, IMO, and GN was using freight car truck side frames instead of special ones as on the Bettendorf trucks. Perhaps Great Northern fabricated these trucks themselves? AFAIK, these are unique to GN.

Brian Leppert
Tahoe Model Works
Carson City, NV

--- In STMFC@..., "aaejj2j" <tyrone.johnsen@...> wrote:




I have posted four prototype photos and one model photo of an Andrews truck as used on the shorter GN cabooses in the Photos section in a new file called GN Caboose Trucks. Of interest here is the spring chamber area. I am interested in information or thoughts on the approach the GN used on these caboose trucks. The GN had similar caboose trucks with "Bettendorf" T-section and perhaps U-section sideframes which utilized the same or nearly the same spring chamber. About up to 1940 the GN cabooses generally used archbar trucks but these 25' wood cabooses were upgraded about in the 1940s and received new trucks, generally Andrews and Bettendorf T-section sideframes. The 1945 and later 30' cabooses like the Ambroid, Northeastern, and PFM Tenshodo models had U-section sideframes with similar spring chambers. I wonder if this approach was unique to the GN or if others had similar trucks. The trucks have a 5-0 or so wheel base and probably came off older freight cars which might have gotten newer trucks of higher load capability. The spring chamber appears to have been flame cut (on the ends) out of a box section of steel. The bolster is seen farther inward.
I photographed this on a car on private property in MT along US 2 and the old GN tracks; but from photos I have seen it is representative. Some older photos may show a sheet metal over the area above the springs. Note I added a plastic foot long ruler to help me determine various lengths.
Of course what I have been trying to do is improve the trucks on my cabooses as I do not like the brass trucks for operation and no plastic framed trucks look correct. Most model trucks are longer wheelbased and if they have real springs their spring chamber seems unrealistically wide. Trucks such as CV or Kadee are often modified with the old Walthers, Silver Streak, Kemtron (I think I have all of these) metal springs result in the springs protruding too far outward, visible bolster end, and too wide a spring opening and without the appropriate enclosure. I have modified some model trucks as IM. I have many more photos and some with dimensions added and some of various model trucks and conversions for those who may be willing or interested.
Thank you,
Tyrone Johnsen
Rockford, IL


John H <sprinthag@...>
 

Brian,

Great info there. I've always wondered how those trucks actually worked. I knew how they looked from the side and obvisouly they had to function but that was as far as my knowledge went. One of those things I was going to research when I got a "round tuit" but just never did. Thanks to you I now understand the design.

Thank you,

John Hagen

--- In STMFC@..., "brianleppert@..." <brianleppert@...> wrote:



This is in response to Tyrone Johnsen's post from eight days ago:

These are Swing-Motion Caboose trucks. Swing-motion trucks differ from conventional trucks in that the truck bolster and spring plank never touch the side frames. Rather, a Transom connects the two side frames. The transom is open in the center from the top thru the bottom. The spring plank hangs from the transom by four links. The springs sit on the spring plank and the truck bolster sits on the springs.

I have added three illustrations from a Bettendorf Co. brochure to the "GN Caboose Trucks" file on the Photos section. These show Bettendorf's Swing-Motion Caboose Truck, their cast Transom and a cross section view which I hope will better explain how these trucks are set up.

Notice that the center line of the leaf springs are inboard of the side frames. This is why less of the leaf springs are visible from trackside.

The transoms on GN's cabooses are kind of crude looking, IMO, and GN was using freight car truck side frames instead of special ones as on the Bettendorf trucks. Perhaps Great Northern fabricated these trucks themselves? AFAIK, these are unique to GN.

Brian Leppert
Tahoe Model Works
Carson City, NV

--- In STMFC@..., "aaejj2j" <tyrone.johnsen@> wrote:




I have posted four prototype photos and one model photo of an Andrews truck as used on the shorter GN cabooses in the Photos section in a new file called GN Caboose Trucks. Of interest here is the spring chamber area. I am interested in information or thoughts on the approach the GN used on these caboose trucks. The GN had similar caboose trucks with "Bettendorf" T-section and perhaps U-section sideframes which utilized the same or nearly the same spring chamber. About up to 1940 the GN cabooses generally used archbar trucks but these 25' wood cabooses were upgraded about in the 1940s and received new trucks, generally Andrews and Bettendorf T-section sideframes. The 1945 and later 30' cabooses like the Ambroid, Northeastern, and PFM Tenshodo models had U-section sideframes with similar spring chambers. I wonder if this approach was unique to the GN or if others had similar trucks. The trucks have a 5-0 or so wheel base and probably came off older freight cars which might have gotten newer trucks of higher load capability. The spring chamber appears to have been flame cut (on the ends) out of a box section of steel. The bolster is seen farther inward.
I photographed this on a car on private property in MT along US 2 and the old GN tracks; but from photos I have seen it is representative. Some older photos may show a sheet metal over the area above the springs. Note I added a plastic foot long ruler to help me determine various lengths.
Of course what I have been trying to do is improve the trucks on my cabooses as I do not like the brass trucks for operation and no plastic framed trucks look correct. Most model trucks are longer wheelbased and if they have real springs their spring chamber seems unrealistically wide. Trucks such as CV or Kadee are often modified with the old Walthers, Silver Streak, Kemtron (I think I have all of these) metal springs result in the springs protruding too far outward, visible bolster end, and too wide a spring opening and without the appropriate enclosure. I have modified some model trucks as IM. I have many more photos and some with dimensions added and some of various model trucks and conversions for those who may be willing or interested.
Thank you,
Tyrone Johnsen
Rockford, IL


soolinehistory <destorzek@...>
 

--- In STMFC@..., "brianleppert@..." <brianleppert@...> wrote:

The transoms on GN's cabooses are kind of crude looking, IMO, and GN was using freight car truck side frames instead of special ones as on the Bettendorf trucks. Perhaps Great Northern fabricated these trucks themselves? AFAIK, these are unique to GN.

Brian Leppert
Tahoe Model Works
Carson City, NV
Tyrone and I had discussed these in person a while back, and I postulated that these were an early version of the Bettendorf cast transom, meant to fit a standard sideframe, but I could never find anything to substantiate this.

A question that comes to my mind is what holds these trucks together? For that matter, what holds a Barber-Bettendorf truck together?

The earlier iterations of this design, using wood transoms and arch bar sideframes, just had the transoms bolted directly to the side frame. This essentially locked all four wheels into a non equalized rigid frame, much like a one piece molded model truck. However, I'm sure the wood transoms were limber enough that they just twisted sufficiently to allow all four wheels to remain in contact with uneven track. Even the later swing motion archbar trucks that used steel channel section transoms were likely somewhat flexible, since the transoms were not unified into a box shaped fabrication with cover plates. The Bettendorf cast transoms are a box section, and are not likely to twist to allow the sideframes to equalize. That means that there must be some allowance for motion between the sideframe and the end of the transom casting, and indeed, they do obviously appear to be separate pieces with some clearance between. But, what held them together? It isn't very obvious from the drawings, and I've never had the opportunity to dismantle a prototype truck of this sort.

Dennis


brianleppert@att.net
 

The Bettendorf and Barber-Bettendorf Swing Motion caboose trucks were pinned together, in a way.

Each side frame had a vertical hole centered on the spring seat. Each transom had corresponding pins (or lugs or bosses--whichever is the correct term) cast on the bottom. During assembly, there is enough vertical clearance between the transom and side frame opening for the pin to clear the spring seat before dropping into the hole. After that, gravity works. As for the GN trucks, I have no idea.

Brian Leppert
Tahoe Model Works
Carson City, NV

--- In STMFC@..., "soolinehistory" <destorzek@...> wrote:

snip

A question that comes to my mind is what holds these trucks together? For that matter, what holds a Barber-Bettendorf truck together?

The earlier iterations of this design, using wood transoms and arch bar sideframes, just had the transoms bolted directly to the side frame. This essentially locked all four wheels into a non equalized rigid frame, much like a one piece molded model truck. However, I'm sure the wood transoms were limber enough that they just twisted sufficiently to allow all four wheels to remain in contact with uneven track. Even the later swing motion archbar trucks that used steel channel section transoms were likely somewhat flexible, since the transoms were not unified into a box shaped fabrication with cover plates. The Bettendorf cast transoms are a box section, and are not likely to twist to allow the sideframes to equalize. That means that there must be some allowance for motion between the sideframe and the end of the transom casting, and indeed, they do obviously appear to be separate pieces with some clearance between. But, what held them together? It isn't very obvious from the drawings, and I've never had the opportunity to dismantle a prototype truck of this sort.

Dennis


aaejj2j
 

Thanks to Brian for posting the info and illustrations and comments on the later B-B Swing Motion Caboose Trucks and to Dennis for his comments. I agree, the side frames appear to be older Andrews and T-section with intregal journal boxes off older freight cars with the addition of a built up transom very similar to the later B-B Swing Motion Truck that Brian supplied the illustrations of and offers in HO (usable on the longer GN 30' cabooses). The transoms on these older 25' GN cabooses appear to have been fabricated using various steel shapes welded together; and appear to be unique to the GN. Although I do have additional photos of the underside of the display caboose I can not and do not remember any other significant features to illuminate the details to which Brian and Dennis have commented. I do remember stops and rollers (more wheels) near the upper junction of the side frames and the transom. I am somewhat familar with the old illustrations and text in White's books and in the 1919 CBC but I was not really studying the total truck construction when I stopped to view, measure, and photograph it during a trip through MT.
Key visual items to me are the visible rectangular box transom, the recessed nearly not visible bolster end, short exposed protrution of the leaf springs, and the shorter wheelbase when compared to existing model caboose trucks - the undesirable (to me) brass trucks do better replicate the prototype.
The purpose was solely to gain info for a better representative plastic model for myself. That said, understanding the prototype as Brian and Dennis discuss is of interest and has been appreciated.
Sorry for the slow response as I have been gone the past week.
Again thanks for the info,
Tyrone Johnsen
Rockford, IL