CONVERTING MTH 72FT CENTERBEAM'S FROM 3 RAIL TO 2 RAIL TRUCKS.

Almost all MTH cars have to be dismantled first to get to the truck screws.  For flat cars this should be simply a case of unscrewing the screws that hold the underframe in place.

Once you lift out the underframe, the truck screws will be revealed.  The thing is that Atlas trucks have a shoulder which comes up to meet the pivot point on the car and the screws attach from below.  Conversely on the MTH cars (at least the modern Premier ones) the car underframe comes down to meet the truck and the screws go in from above.  The two trucks are very different designs - when I offered them up I concluded there was no hope of making them work.  I proceeded to obtain the appropriate MTH 2-rail trucks and fit those instead - for modern roller bearing trucks the part number is 20-89002.

With those the conversion is quite easy for most cars although I haven't tried the Centerbeam.  Hope this helps.

Regards, Bevis.

I've converted the MTH Centerbeam Flat to Atlas trucks. You do need to dismantle the car, as the MTH truck screws are fitted from the top, rather than from underneath.

I use the Atlas truck with the plastic 'spacer' attatchment supplied with them as spares, with a small metal washer to help centering, as the MTH hole is a bit wider than the Atlas piece, & I also use a thin rubber 'O' ring of about 1/2" overall dia. between the truck & frame to reduce 'wobble', as tightening the Atlas screw right up still doesn't hold the truck up against the car.

Sure someone has posted on here before about it, as it's more-or-less their method I copied!!

Best thing about the Atlas trucks is the rotating bearing caps, of course. The MTH 'roller bearing' trucks don't have this feature.

There should be holes in the underframe that are Kadee-compatible, though you may need to shim the draftgear boxes down a bit to get the coupler height right.

Thank you BEVIS KING&SUNDAYSHUNTER for your help on the centerbeams.

My car must be old as it has no Kadee pads. I'm going to have to do a lot of careful measuring to get this right.

These cars should have lower shelf couplers. For those in the more modern era where these are used,go to this link. https://www.dropbox.com/s/brli...%2011.27.03.jpg?dl=0  Wish I could get more info on these plus a release date as well as pricing.

Thanks again gentlemen.

As Always,

Al Hummel

Al, Look like some great coupler options for modern era guys.  Which ones are those?

Mike ,

Yes,these look great. They are a Protocraft type coupler,though not produced by Protocraft. There's a single lower shelf,a double shelf for tankers and an H tightlock for passenger cars. According to the photos,they've been produced but not cleared for release to us modelers yet. I don't know why someone hasn't at least announced that the project is in the works even if not ready for sale.

Did you see the new Prototype model of a Racor operating groundthrow switchstand? This model is a "first" in any scale. New Century throws are on the way. The Racor model is ready for sale and are $24.95. I think the link here,is aatlarry@allaboardtrains.com. It's 3:39am so if that link doesn't go through,let me know and i will look it up again.

Thanks for the interest Mike,hope others will show interest,also.

As Always,

Al Hummel

Thanks Al.  Definitely interested in these advancements for O Scale!

I've converted three older MTH center beam cars from hi-rail to 2-rail, partly because the original truck locations on the cars were incorrect, partly because I'm a not-so-closeted 2-railer running at a 3-rail club. The conversion technique I used was a combination of how Brian Biggs converted early MTH auto racks, Dave Branum's conversion article from O Scale News several years ago, and a tweak I did to better support the trucks.

First, the photos:

Burlington Northern car before conversion. I had dumped the original loads in favor of some wood lumber loads I picked up off eBay. About 30 seconds after I had the loads in I knew I had to convert it -- those trucks just looked WRONG where they were mounted. The newer hi-rail cars have the trucks in the right place, but they haven't released a lot of them. The older ones show up periodically on eBay, which is where I got the UP cars. The Burlington Northern and the Tobacco Railway are "opera window" Center Beam cars (which is why there are only two rows of loads). The opera window cars are hard to find.

UP Car post-conversion. I took the weight from the second car (identical number) and added it to this car so I could run it empty.

The cars in a scale-wheeled consist on the club layout.

Loaded UP car.

The technique is actually pretty simple.

1. Remove the screws holding the underframe detail on the car.
2. Cut the underframe at the center sill edge of the bolster. (For the newer cars, they properly located the trucks, so you just need to remove the trucks and replace them with the MTH 2-rail trucks and mount the Kadee couplers and you're done.)
3. Cut approximately 1 1/8 (as I recall) of frame away. from each end of the under frame center section.
4. Cement the bolster to the underside of the car body with the ends aligned with the jack pads on the body (correct location).
5. Cut a 1/4" piece of 3/8" wood dowel and cement it into the truck mounting hole on the bolster. Your Weaver truck will screw into this.
6. Glue three 3/8" washers to each bolster around the dowel This supports the truck cross beam and keeps the car level. It's invisible (you can paint it black to be more invisible).
7. Notch the end sill "bump" where the coupler draft box should be to accommodate the Kadee draft box. I used a razor saw to make two small cuts down the sill, then an X-Acto to score and snap the horizontal cut at the bottom of the body.
8. Drill 1/16" holes to mount the Kadees. I used a small shim to level the couplers.
9. I used Weaver Plastic trucks with 33" Intermountain metal wheels and the coupler heights were right on target.

Here's a close-up of the bolsters. I made the ones for the BN car. I got lazy (or smart) and cut off and reused the MTH bolsters with a small dowel inserted for the UP cars. With the washers installed, it supports the trucks well. The cars ride nicely and track well.

To convert an older MTH Auto Rack, you use exactly the same technique -- i.e., cutting out part of the chassis and putting in bolsters. I opted to re-use the MTH parts and wood dowels as it took less time. I actually made bolsters for the Burlington Northern car.

Weight wise, the loaded cars are a bit heavy at roughly 27 ounces because of the loads, but they track well in a train. My understanding is that technically  I should have used 36" wheels but in this configuration, the cars are more tolerant of the uneven spots on the club layout. The new wheelbase will allow the cars to handle 36" radius curves (O-72 in hi-rail speak). I'm going to do a conversion on several older MTH Auto Racks I have in my collection.

Hope this helps. If you need some detail photos, I'll take one of the cars apart and get some more photos.

Matt, Nice conversion.  Thanks for sharing!

Mike DeBerg posted:

Matt, Nice conversion.  Thanks for sharing!

Thanks. Sometime in the next few weeks I'll be doing a couple of auto racks.

Nice conversion , makes for a more prototype ride height , too bad none of MTH's cars have an accurate road number , no large railroads have 4 digit road numbers , shows how lame MTH is in the research dept.

so to finish the job now one must find a road number  that matches the  car type and paint scheme

AGHRMatt posted:

Mike DeBerg posted:

Matt, Nice conversion.  Thanks for sharing!

Thanks. Sometime in the next few weeks I'll be doing a couple of auto racks.

Matt you mention that the newer MTH centerbeams have the trucks mtd correctly, obviously a newer bottom frame, the newest catalog still pictures these cars with the older out to the end truck mtg is this just a catalog use of older pics ? or has MTH indeed put a new frame with correct truck mtg locations, would like to know for sure before I pre order some.

Hands down one of the best conversions done on the MTH centerbeams, is this car from Bernie Winkler....

hibar posted:

AGHRMatt posted:

Mike DeBerg posted:

Matt, Nice conversion.  Thanks for sharing!

Thanks. Sometime in the next few weeks I'll be doing a couple of auto racks.

Matt you mention that the newer MTH centerbeams have the trucks mtd correctly, obviously a newer bottom frame, the newest catalog still pictures these cars with the older out to the end truck mtg is this just a catalog use of older pics ? or has MTH indeed put a new frame with correct truck mtg locations, would like to know for sure before I pre order some.

IMO, especially if you plan on using Atlas 100-ton RB trucks, I would gut that part of the bottom underframe, including the bolster.  I've done that with old and newer MTH cars with great success.  Will send photos later today.  Similar to the photos above from Matt... Definitely not the quality of Bernie's work, but provides a great ride height as well as gives a much better side appearance without the center sill.  I've rebuilt the center sill with styrene as well as just cut off the drop portion with great success.   

Modifying  older MTH centerbeams is not a problem, still asking if the newest releases of what appears to still be the original MTH tooling on these cars has corrected the truck spacing, Matts original post seems to indicate this is the case, as all ways SCRATCHBUILDER1-48s work is exceptional.

The newer centerbeam cars have the trucks in the correct position- this was corrected many years ago, but they are still using the old artwork in catalog pics.

Sorry Hibar, yes the trucks are in the correct position on the newer cars as Jeff points out.  I was trying to suggest that depending on the trucks you plan on using and the look you're going for, might still be a better plan to modify the car regardless of old vs new?

Mike, first- nice pics!! And I agree, modifying the bolster here lowers the car to a more realistic ride height. 

Thanks for info, I use Weaver diecast RB 36T 2 rail trucks, kaydee w/long shaft couplers and add cut levers and air hoses, will order from latest Catalog so as to not cut up frame and modify bolster area accordingly for correct ride and coupler height. I hope eventually Atlas produces this car I think in a Masterline version [either line would work for me] it would sell out. JMO

Outstanding work as always, Bernie.

The big reason I didn't just use MTH 2-rail trucks on the UP cars was that the car rides about 1/8" too high. The end sill "bump" on the MTH car should be notched out for the coupler. Even though it appears the prototypes use long-shank couplers, I opted for standard length 700-series Kadees as they'll clear sharp curves and the standard shanks are actually a bit longer than prototype anyway. What's starting to bug me is that the only ones showing up on eBay are priced higher than original retail -- all this to find another BN opera window car.

hibar posted:

Thanks for info, I use Weaver diecast RB 36T 2 rail trucks, kaydee w/long shaft couplers and add cut levers and air hoses, will order from latest Catalog so as to not cut up frame and modify bolster area accordingly for correct ride and coupler height. I hope eventually Atlas produces this car I think in a Masterline version [either line would work for me] it would sell out. JMO

I absolutely agree with you on Atlas making this in the masterline, it would be the new standard in O scale.  Similar to what Atlas accomplished with the Trinity 5161 covered hopper. I would be in for CN, IC, WC, BCR, TTX, GTW, AOK just to name a few!

Did some more research MTHs UP273547 is accurate for model although they managed to get the trucks mounted slightly more inboard should center on lifting gussets as per Matts conversion also included pic of TTXZ with trucks mounted out to end steps as per MTH original models obviously crude basic underbody on models compared to Bens work.

Newest project this is one of the very few accurate paint schemes from MTH for these cars, the prototype was an 86/87 Thrall car with the correct shorter truck spacing used I believe because of the 10'+ solid centerbeam paneling inboard from both ends before open posts. I have added end details plus Atlas 2 rail trucks would look better with the newer Atlas thin frame trucks, big advantage of Atlas trucks is ease of mounting a 10-24 3/4" machine screw and nut along with a suitable spring from any ball point pen with a fat spring works great, remove frame and mount trucks nut just fits round back side of frame after remounting frame trucks can be removed and nut stays in place without turning. I took this a step further by filing down top screw on plate of trucks to near flush with inside lower mtg post this is as low as you can bring carbody with out hitting tops of 36" wheels on under frame on curves still requires spacer under KD 706 long shank box about 1/32"  more if you do not file truck tops I make mine from sheet styrene , car is still to be touched up and weathered. When MTH first introduced this car some catalog pics were of HO model with correct truck spacing.