MTH CENTERBEAM WHEEL REPLACEMENTS

Alan,

JEFF78RR has some nice tricks for lowering these cars and making them ride and look more prototypical! 

Mike DeBerg,

Thanks Mike. How about radius on curves for these any reason they shouldn't hold fine to 50" Radius?

Thank you.

Al Hummel

I did a 2-rail conversion on an older one. It's pretty simple. The old ones had the wheels set at the extreme ends of the car when the truck center should actually be lined up with the jack pads farther in. Here's what you do:

1. Remove the chassis
2. Remove the trucks (they screw in from the top of the chassis)
3. Cut the ends containing the truck mounts (you won't be reusing them)
4. Cut out a 1" (roughtly) section of the chassis underframe detail near each end of the centersill to shorten it.
5. Install a 1/4" thick piece of basswood between the jack pads on the body. This will function as the bolster.
6. Drill 1/16" hole in the center of the bolster
7. cut out the "bump" on the end sill where the coupler is supposed to be.
8. Mount a Kadee 740 on each end
9. Screw or glue the underframe back on
10. Install a pair of Weaver trucks with Intermountain metal wheels using 2-56 screws..

The car's weight will be pretty close to what it should be and will negotiate 36" radius curves without any problems. The photo of the cutouts is courtesy of Brian Biggs, who gave me the heads up on the conversion (he did autoracks, but the procedure is the same. Thanks Brian. I picked up the lumber loads from a guy on eBay. They come in sets of nine, so I ordered six sets to do the car, but decided to leave out some of the center ones. They were supposed to be assorted, but he did them all in a single branding for me.

easiest way is to get MTH's 2 rail trucks, the under frame  is despicably wrong on this beam cars though. I have a couple.

Here's the way I am doing it

Did MTH originally release these cars with the bolsters in approximately the correct location? I have seen a couple of cars in which the bolster appears to be "aligned" with the jack pads as noted on this Ebay offering and notice the relief for the shank of the coupler as well.

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

I was not sure whther MTH actually made the car this way or whether this was modified. 

Great looking cars but the location of the trucks toward the car ends looks awkward.

@AGHR Matt:- thanks for that post, fantasticly helpful!! I've been looking at my Centerbeam with regards to moving the trucks & re-doing the underframe. Planning on using Atlas trucks though so as to have rotating bearing caps. 

Do Centerbeams have 33" or 36" wheels, anyone tell me?

SundayShunter posted:

Do Centerbeams have 33" or 36" wheels, anyone tell me?

Look at the end of the car.  Prototype cars usually have information stenciled there indicating things like wheel size and wear, as well as brake beam and draft gear specs.  Of course, even if there, the data may not be accurate.

My guess is 36" wheels.  If the cars are rated for 100 tons lading, then they should use 36" wheels.  If they are rated for 70 tons lading, then typically they would employ 33" wheels.

Our go to this BNSF equipment page.  It indicates 36" wheels.  And just about every other possible specification.

SundayShunter posted:

@AGHR Matt:- thanks for that post, fantasticly helpful!! I've been looking at my Centerbeam with regards to moving the trucks & re-doing the underframe. Planning on using Atlas trucks though so as to have rotating bearing caps. 

Do Centerbeams have 33" or 36" wheels, anyone tell me?

You're most welcome. The next cars I do will be done with Atlas trucks -- several older MTH autoracks and another center beam flat car. I used the Weavers because I had a batch of them lying around. Turns out I used the wrong wheels as mentioned above (33" vs. 36"). The Atlas trucks would be the 100-ton. You're definitely right about the rotating bearing caps being nicer.

NEPA posted:

Did MTH originally release these cars with the bolsters in approximately the correct location? I have seen a couple of cars in which the bolster appears to be "aligned" with the jack pads as noted on this Ebay offering and notice the relief for the shank of the coupler as well.

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

I was not sure whther MTH actually made the car this way or whether this was modified. 

Great looking cars but the location of the trucks toward the car ends looks awkward.

The later ones were done with longer shanks and the trucks in the right place. They also did it with the Autoracks. In the case of those cars, they also put Kadee mounts, but the car rides about 1/8" too high with the MTH 2-rail trucks in place. I like the look of the converted cars better as they ride lower. They should still be able to handle 36" radius without the trucks hitting the sides.

Thanks for the further info re wheel size!

My Centerbeam takes 36"radius easily enough, although from above it does look rather silly. From track level, & inside the curve, it isn't so bad.

Also I have fitted long-shank Kadee #746 couplers, but using an Atlas spring in the draftgear box. The stiffer Atlas spring stops the coupler sagging, although it does mean coupling up is a bit harder & I imagine magnetic uncoupling isn't very reliable either, but I use BBQ skewers for that myself.

PS, the Grain Elevator in the pics is HO scale.... an attempt to try & get a sense of distance in a small area through forced perspective. Layout still very much "under construction" !!!

Sunday Shunter:

I think your coupler choice is the correct one. Some photos I've seen seem to show longer shanks on the center beam cars. I like the idea of using Atlas centering springs. I have a couple of Atlas 89-foot flats I switched over to Kadees and the complers sag a bit. Also like the use of the H.O. structure for forced perspective.

AGHRMatt posted:

NEPA posted:

Did MTH originally release these cars with the bolsters in approximately the correct location? I have seen a couple of cars in which the bolster appears to be "aligned" with the jack pads as noted on this Ebay offering and notice the relief for the shank of the coupler as well.

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

I was not sure whther MTH actually made the car this way or whether this was modified. 

Great looking cars but the location of the trucks toward the car ends looks awkward.

The later ones were done with longer shanks and the trucks in the right place. They also did it with the Autoracks. In the case of those cars, they also put Kadee mounts, but the car rides about 1/8" too high with the MTH 2-rail trucks in place. I like the look of the converted cars better as they ride lower. They should still be able to handle 36" radius without the trucks hitting the sides.

Matt, many thanks for clarifying. It seems MTH uses the same part number regardless of the truck position. Unfortunately the catalog images are not helpful. When you mention "the later ones" do you know when this change was made and whether it affected all. Any info or images you can provide will be helpful. Many thanks in advance.   

NEPA posted:

AGHRMatt posted:

NEPA posted:

Did MTH originally release these cars with the bolsters in approximately the correct location? I have seen a couple of cars in which the bolster appears to be "aligned" with the jack pads as noted on this Ebay offering and notice the relief for the shank of the coupler as well.

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

I was not sure whther MTH actually made the car this way or whether this was modified. 

Great looking cars but the location of the trucks toward the car ends looks awkward.

The later ones were done with longer shanks and the trucks in the right place. They also did it with the Autoracks. In the case of those cars, they also put Kadee mounts, but the car rides about 1/8" too high with the MTH 2-rail trucks in place. I like the look of the converted cars better as they ride lower. They should still be able to handle 36" radius without the trucks hitting the sides.

Matt, many thanks for clarifying. It seems MTH uses the same part number regardless of the truck position. Unfortunately the catalog images are not helpful. When you mention "the later ones" do you know when this change was made and whether it affected all. Any info or images you can provide will be helpful. Many thanks in advance.   

I'm not real sure. I want to say around 2005-2006 is when things started changing -- Kadee mounting pads seem to be the key factor. You probably have to look up the catalog number on the MTH site and see if Kadee mounting pads are part of the description to get an idea.

Many thanks Matt....good idea on the descriptions!!

NEPA posted:

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

Sorry everyone - I bagged the Centerbeam; Seller accepted a Best Offer

SundayShunter posted:

NEPA posted:

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

Sorry everyone - I bagged the Centerbeam; Seller accepted a Best Offer

Hey it happens. I bagged a UP version over the weekend, plus a bunch of lumber loads to fill it. I have another one and I'm going to set them up for a sleight-of-hand loads in/empties out operation of some kind.

Well as my pics show above, I have an opera-window style one (I think that's the usual description?) & wanted a more up-to-date truss type, as a contrast as much as anything, but the truck position will be interesting to compare as well.

Finally finished another pair of Center Beam cars -- this time UP with the more current style of center beam support. Decided to use Weaver trucks again with the [correct] 36" wheels this time and Kadee 740 couplers rather than long shanks since they worked with the first car. Used a different technique to mount them, using the existing MTH bolsters, but gluing in a 1/4" diameter x 5/16" dowel to mount the truck and washers to support the truck and prevent rocking from side to side. They turned out pretty nicely. I'm going to use the technique on my old MTH Auto Racks. I modeled one car loaded and one empty (added the car weight from the loaded car to bring the weight up). I'm going to test them out at the club this weekend. The cars have the same road number for loads-in/empties-out operation between a plywood manufacturer and a lumber company module set I was thinking about.

AGHRMatt posted:

NEPA posted:

Did MTH originally release these cars with the bolsters in approximately the correct location? I have seen a couple of cars in which the bolster appears to be "aligned" with the jack pads as noted on this Ebay offering and notice the relief for the shank of the coupler as well.

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

I was not sure whther MTH actually made the car this way or whether this was modified. 

Great looking cars but the location of the trucks toward the car ends looks awkward.

The later ones were done with longer shanks and the trucks in the right place. They also did it with the Autoracks. In the case of those cars, they also put Kadee mounts, but the car rides about 1/8" too high with the MTH 2-rail trucks in place. I like the look of the converted cars better as they ride lower. They should still be able to handle 36" radius without the trucks hitting the sides.

Matt, do you know the approximate item numbers or year for the truck location change?

BobbyD posted:

AGHRMatt posted:

NEPA posted:

Did MTH originally release these cars with the bolsters in approximately the correct location? I have seen a couple of cars in which the bolster appears to be "aligned" with the jack pads as noted on this Ebay offering and notice the relief for the shank of the coupler as well.

http://www.ebay.com/itm/MTH-Pr...b:g:fOQAAOSwZd1Vb00E

I was not sure whther MTH actually made the car this way or whether this was modified. 

Great looking cars but the location of the trucks toward the car ends looks awkward.

The later ones were done with longer shanks and the trucks in the right place. They also did it with the Autoracks. In the case of those cars, they also put Kadee mounts, but the car rides about 1/8" too high with the MTH 2-rail trucks in place. I like the look of the converted cars better as they ride lower. They should still be able to handle 36" radius without the trucks hitting the sides.

Matt, do you know the approximate item numbers or year for the truck location change?

I believe they started that around 2006-2007. I recall they did the auto racks at the same time. I have a couple of the newer auto racks and I'll check the item number against the catalogs. The MTH cars with Kadee mounts will have the couplers at the right height when used with the MTH 2-rail trucks, but the couplers will be mounted below the "bump" in the end sill. My conversions have the coupler in the end of the sill where they're supposed to be and sit about 1/8" lower.

Matt,  Really nice job on these cars!

rdunniii posted:

Here's the way I am doing it

 

I wonder what trucks and wheels these are?

Mike DeBerg posted:

Matt,  Really nice job on these cars!

Thanks. It's a learning process. I'd like to try it with some Atlas trucks but I have to figure out a durable way to make a truck pin. One thought is using a 3/16" stud or rod epoxied to the bottom of the car (or threaded into the floor), drill out the truck slightly and maybe use a C-clip or cotter pin to hold it in place.

Engineer-Joe posted:

rdunniii posted:

Here's the way I am doing it

 

I wonder what trucks and wheels these are?

They look like Atlas. Nice low mount. I set my ride height a bit higher to allow for more swivel on the trucks for sharper curves.

Engineer-Joe posted:

rdunniii posted:

Here's the way I am doing it

 

I wonder what trucks and wheels these are?

Weaver plastic trucks with NWSL wheels.