bogies in kato DD51 too tight

[ianlaw]

Hello,

Has anyone tried to increase the play on the bogies of the kato DD51 (N-gauge). Due to the construction they are extremely limited in tilting freedom. Basically the loco has never been able to run any distance on my layouts without derailing.

[Dinosbacsi]

I suppose the problem is the middle bogey?

[ianlaw]

Nope. The middle bogie is fine. Even negotiating a small cant (twist in the track) will through the leading axle off the track as the bogie can't tilt sideways to accommodate the track. All my other bogie stock is fine. So it also happens on wide curves.

[katoftw]

Give the bogies a push into the chassis.

 

Sounds like the have popped out a little. When this happens, their range of movement massively decreases.

[ianlaw]

Too bad... probably the pockets in the chassis need a bit of machining. It's gone back to live in the show cabinet. Luckily I have enough other rolling stock.

[disturbman]

Did you try pushing/putting them back?

[cteno4]

Also looks as at time pickup contacts can also get a bit out of place and not allow the trucks to snap in all the way. As other have noted popping out the trucks, making sure everything is in correct place then resnappping them in may get them working properly.

 

did you get this new or used?

 

worth a shot if it’s just going in the display cabinet otherwise.

 

Jeff

[ianlaw]

Yes I've had the bogies out and back in. In the past I remember getting it running on the previous smaller layout in one direction by shimming the front of the bogies in the direction of travel with paper shims which put slightly more pressure on the leading axle and thus prevented it jumping the rail. I didn't have any canted curves back then.

It was bought new a few years ago. 

[cteno4]

Bummer. Sounds like something is seriously amiss with the bogie clips or the chassis bogie housing, they should turn pretty easily. When I’ve had them bind it’s either not clipped in all the way or contact strip or pickup wiper has gotten out of place and prevents either clipping in all the way and/or binding up the turning of the bogie.

 

jeff

[Kiha66]

Another issue with the kato DD51 if the bogie has come out (or was incorrectly installed at the factory) is ensuring the internal driveshafts are correctly seated in the flywheel.  I'm not sure how to show it, but if they haven't gone in correctly they'll push the track out of the chassis and lead to very poor running.

[ianlaw]

Thanks for all the suggestions, but pushing the driveshaft further into the flywheel just made it worse.  I then oiled the top and sides of the turrets of the bogies that fit in the pockets of the chassis and that combined with paper shims will keep it on track most of the time.... hmmm, Just too bad it still won't exit the diesel route back into the fiddle yard. I've also noticed there seams to be quite a bit of play of the axles in the bogie itself. It looks as if the axle will move up in the bogie by more or less the flange height and that seems to be problem on said pointwork.

[ianlaw]

Suddenly it's decided it will pass said set of points... The paper shims are not glued in place yet and move around, so I need to get them just right.

[inobu]

Are you running it with the shell on or off?

 

Run it with the shell off so you can see what is going on.

 

Place it on a piece of curve track where you can see all angles and post the picture.

 

Inobu

[inobu]

This video makes me think there is some kind of anomaly with the bogie. 

 

I'm wondering if the bogie has a front and rear position/direction.  I would look for an assemble error

look for the arrow that indicated to front.

 

Inobu

 

 

Edited November 2, 2021 by inobu

[ianlaw]

Thanks for the additional suggestions. It seems that somehow the bogies sit just slightly too deep in the pockets. I have glued the shims in place (with PVA glue so can remove if required) so cannot disassemble at the moment, but with the oil and shims as described it's running ok. If it starts playing up again I'll check for the above.

[Kamome]

I know this is a slightly old issue. Correctly housed the DD51 bogies will navigate R-249 curses without issue. 

 

2 other possible things to check. The underside detail piece is correctly positioned. The bogie assembly housing is correctly positioned. Both have details with a very slim margin for error and will foul each other if not correctly positioned. The same can also be said for the snow plough and coupler assembly. The front of the bogies will catch this quite easily.