Our Ball Bearings for rolling stock come in two sizes, 6mm and 7/32". The 6mm fits the Aristo® Bettendorf® freight truck and has an ID of 3.1mm. The 7/32, fits the Aristo modern roller bearing truck with roller caps without modification, and has an ID of 1/8"

The 6mm bearings sell for $18.00 for a package of 10. The 7/32" sell for $19.00 for 10. These bearings are flanged and are double shielded. They do not require lubrication.

To install the 6mm bearing in the Aristo® Bettendorf® truck, simply remove the plastic axle insert with a #6 tap or a #6 dry wall screw. If you have a counter sank bit, taper the outside of the hole by hand slightly. This will help you align the bearing with the hole. Turn the side frame over with the bearing started and push the bearing into the hole using a flat surface. I find this works well for me.

To install the 7/32 bearing in Aristo® modern roller bearing trucks with roller caps, you will have to disassemble the truck side frames. Take a punch and knock out the brass bushing and push in the 7/32 bearing. If you find that the bearing is difficult to insert use a 7/32, drill and clean out the hole by hand only.

To use these bearing in Aristo® passenger trucks, you will have to disassemble the truck, remove the brass bushing, and drill the exiting axle hole to fit the bearing you intend to use. The bearing can also be used as a electrical pick up by making a small notch on the side of the hole and inserting the wire then installing the bearing.

These bearings can be installed in other manufacture trucks by drilling a hole using the exiting axle hole as the center for the new hole.

There are two trucks that will not accept these bearings. The Aristo® Sierra® passenger truck and the LGB® simulated roller bearing truck.

If you would like us to drill the truck side frame and mount the bearings, the cost will be $0.50 a hole plus return shipping. Please send only the side frames.

We also stock a bearing replacement kit for Aristo® new fourwheel diesel motor truck with open face bearings. The bearings we carry are double shielded and very smooth rolling.

The kit to do two motor trucks sells for $15.00.

USA® Conversion Kit Instructions

The kit will consist of eight 6mm unflanged bearings and four insert bushings. Each axle will have one wheel as a pick up, and one wheel insulated. Since the truck frame is metal this will allow each truck assembly to be electrified using one truck as a plus pickup and one as a minus pickup for the lighting. The cost for the kit is $25.00.

To do the conversion yourself, disassembly the truck by removing the brush holder and four screws that hold the side frames on. You will need to get a #2 screw extractor and a tap holder to hold the extractor. Insert the extractor into the bushing and turn counter clockwise and pull towards you the bushing will come out easy. You will notice that the bushing hole is two sizes the outer hole is .258 dia. and about 1/16' in depth. The inner hole is .235 dia. and about 3/16" in depth which allows for a press fit of the 6mm bearings. When pressing in the bearings try to press it in fl;ush with the inner bearing hole. Remove 1 wheel from the axle and remove the plastic bushing. You will have to get a .315 chucking reamer to enlarge the ID hole on the wheel from .313 to .315 the bushing OD is .316 and will allow for a press fit. Install the metal bushing and reinstall the wheel on the axle. Install nylon spacer on the axle. Since the bearings are recess this will keep the axles from to much side play. Before reassemble the truck, rotate each spring on the side frames about four complete turns. This will remove the paint and assure good electrical contact between the lower and upper part of the side frame. Attach the red wire to one truck and the black to the other truck. I find that by adding a small lug to the wire and attaching the lug to the hole that was used to hold the brush holder on the frame works fine.

If you would like Great Big Trains to do the conversion for you (drilling, bearings, and bushing), the cost will be $45.00 for a pair of trucks plus shipping.

AMS® Conversion Kit Instructions

Remove the side frames. Take a #3 screw extractor and remove the brass bushing in the side frame. Install the bushing in the kit first and then the bearing. Take a duck bill pliers and squeeze the lip where the bearing rests just hard enough to keep the bearing from coming out. Now, this is the hard part. You will need access to a lathe. Remove the wheels from the axles. The outboard part of the axle (1/4”) will have to be turned down to .115” +.001” or -.002”. Reassemble the wheels.

Great Big Trains offers two options to help you with this conversion:
1) Send us the side frames and wheels and we will convert them for you at a cost of $30.00 per four side frames and wheels. This includes the bearings and turning down the wheel axles. Add shipping.
2) Send your axles and Great Big Trains will turn them down for you at a cost of $16.00 for four axles. Add shipping.

Remove the trucks from the car. Remove the 4 small screws that hold the 2 side braces (Be careful not to drop the screws). Remove the 2 side frame screws on 1 side frame. Place a common screw driver between the wheel and side frame and twist to pry the side frame up to loosen the rotating bearing caps and remove. Remove the side frame from the wheel axles. Do the same to the other side frame. Put the side frame between the 2 jaws of a hobby vice or 2 small blocks of wood and, with a punch, knock out the 9mm bronze bushing. Take the 9mm bearing and install the nylon spacer in the bearing ID by tapping with a small hammer. Install the bearing in the side frame (You may need to tap the bearing into the side frame). It is a tight fit.

Re-assembile the truck in reverse order and install the rotating caps last.

Price: $17.50*, includes package of ten bearings.

Please feel free to contact us with any question you may have.

George Bellopatrick, Great Big Trains

Phone: 303-362-0951
Fax: 303-256-5489
E-mail: information@gbtrain.com