Or make the centre wheelset flangeless.
In theory ............ if your con rods use the same hole pattern as the Piko ones, then the remaining differences are cosmetic ..... except
Is there a clearance problem at the back end of the slide bar ? I did have that issue on a scratch-built loco
I fitted the running gear off this one, to my other 0-6-0 and it runs perfect with the gear / rods off this box , so I don't believe there is anything different with the rods compared to the first one I made. Hence removing the gearbox and looking for what else is wrong. The tightness is on the front set of wheels but not every rev but when the gear has jumped a tooth or two then the rods will bind and lock. The set of con rods off this one are still on the other 0-6-0 as they run perfect then theirs no point in swapping them back .I would imagine the misalignment in the con rods has caused damage to the gears rather than vice versa.
Check where the tightness occurs and on which wheel. Chances are the distance between the wheel mounting bosses is slightly different to the rod length and this is causing the binding. Ease the hole out on the rod to give a little bit of free play.
Is it just the picture, or is the middle axle missing something on the bottom wheel?Think I have found the problem with WW gearbox the lid on these have two screws only when you get them but four screw holes I added the other two. It looks like one of the original was screwed in to tight and partially stripped the thread so the lid was lose in one corner, looking at the Gear that meshes with the motor brass Gear it looks a bit stripped on a few teeth which would explain why the con rods go tight some times the motor has lifted enough for the gears to jump hence the damage to the Plastic gears and the connecting rods jamming. All just a guess but will buy new gears, I have already fitted a longer screw in the one that works lose. Ignore the pick up strip that is not runni9ng on the bearing in the pic it was, just the bearing moves when the cover is off.
Just got to work out which Mogul the box was off to buy the gears for it now.
View attachment 288177
The center set of wheels are totally free as a pair to turn on there own, with quite a lot of sideways movement as well to allow cornering, So the only thing that holds them in line with the quartering and turns them is the con rods, I have never looked how LGB do this on blocks with more than two axles, but I can see why its common for the the centre Piko pin that holds the con rod on to shear as it did on the Piko BR80 I have, twice now. The red plastic sleeve on that axle is to limit the sideways movement I guess ?Looking at the picture, is the plastic sleeve under the gear the only thing holding the wheel quartering in the correct position? I'm wondering if this is allowing the quartering to be thrown out, causing the binding and gearbox damage?
Agreed. If the centre axle is fully floating, this can put a lot more strain onto the con rods, as they are essentially holding the wheel into position, while still transmitting power to the 3rd set - out of sight here.
I see what you mean now , the center axle doesn't have any bushes, it's just the axle itself that sits in a vertical slot in the casing just the outher two axles have bearings and both are then driven from the motor, I did look at the centre red sleeve over the axle and all it does is limit the sideways movement of that axle, does this image explain it better.