Gearbox problems in a Mallard Duke

[GWMark]

I am building a Mallard Duke and have a bit of an issue with the gearbox. This is the second box I have fitted, the first interfered with the backhead, currently I have a Branchlines Multibox gearbox that take the drive the rear axle and lets the motor sit nicely in the firebox. The problem is that the final output gear on the rear axle is too large to allow the cab floor to site down, I need something that is about 2 to 3 mm smaller diameter than the gearbox I have. 

 

 

Looking at the HighLevel gearbox planner I can see a couple of boxes that would allow the same arrangement as the Branchlines one does now, the problem is I can see any data on the diameters of the gears themselves.  Doe anybody have this data or experience with the Mallard Duke and getting a modern gearbox to fit it?

 

Thanks

Mark

[Adam]

I can't help with the Duke specifically - attractive loco's though they are - but have you asked Chris Gibbon? I've always found him very helpful. As a rule, I think the gearbox planner shows the gears where they overlap the gearbox and not otherwise (but I would check with Chris about that).

Adam

[Worsdell forever]

Yes, some of the HL gears are within the gearbox and any that are larger are shown on the planner, but as Adam says, give Chris a ring and I'm sure he will have all the measurements.

[GWMark]

Thanks, that's useful to know. I emailed Chris but no reply, I will try calling in the morning if I get a chance.

 

Thanks

Mark

[N15class]

Hi

Looking at the gearbox and sub chassis, can you not drive from the leading driver and still get the motor into the firebox?