Removing crank pins

[cookisan]

Hi, wondering if anybody could help.

 

How easy is it to remove the crank pins from the wheel - connecting rod? Am I right in thinking some are pressed in and others are screwed in.

 

How interchangeable are connecting rods, valve gear and crank pins between different manufacturers and models?

 

I have a bit of an idea for a project to make a passable representation of a chassis type which appears unavaliable, but before I start spending money I was hoping for some advice or experiences.

 

Cheers

[DCB]

Depends on the loco, early Hornby Dublo are pushed through and rivetted over, later ones push in, Airfix used push in, Triang/ Hornby screw in, Mainline tiny securing pins in hollow crankpins, continued by Bachmnn,   Current Hornby seem to use whatever the Chinese decide on from day to day, Romford wheels take Triang screws as the romford crankpin wears, breaks, comes unsoldered, looks daft.

 

Most 00 coupling rods can be interchanged if you open up the crankpin holes carefully with a small needle file, but check the wheelbase of the model as the rod length must be right to much less than a millimetre to get good running.  I use Mainline/Bachmann 57XX Rods and Romford wheels with Triang screws  on K's 57XX and Dean Goods locos.

 

Personally I think 1950 style Hornby Dublo valve gear has never been bettered in OO, especially if you add some width to the motion bracket on the 4MT and 8F as I have done

[cookisan]

Cheers David

 

The information was great, I feel I'm at the top of the slippery slope!

 

Regards

[34theletterbetweenB&D]

If you actually describe the intended project, someone may already have trod that path and have relevant advice.

 

Current Bachmann and Hornby product from tooling created in China over the last fifteen years is pretty compatible, in that the crankpin arrangement is a boss on the wheelface, with a small hex headed screw to retain the rod. Easy  to swap components about, though they must be of matching length in the case of coupling rods, and since not all wheel spacings are to dead scale this has to be determined by measurement.

[cookisan]

I'm trying to make a passable class 15xx chassis. So far the donor chassis' I've looked at only have one of the three criterior I'm looking for, roughly right wheel spacing but wrong wheel diameter, right wheel diameter but wrong spacing and if it has Walschaert valve gear it tends not to have the others!

 

I'm even starting to think about having a go at making the subframe of the chassis from scratch and use donor parts for the connecting rods, valve gear and motor.

 

I seem to have slightly lost the plot regarding panniers!

 

Thanks for your info.

[DCB]

I guess you are talking GWR outside cylindered Pannier 15XX  not a GWR Saddle ? Pannier of the 1501 series or a great Eastern 4-6-0, in which case with a  6 foot 4 and 6 foot 6 wheelbase, plain coupling rods, fluted Con rods and a visible joint in front of the centre driver which is 4'7" with the 12" throw crankpin on the spoke.  ..  I had plans for such a beast, not fine scale but Mainline 22XX boiler, Lima or wills 94XX tanks and cab and a 1950S  Triang Princess Chassis, the screw together type which from memory at 26mm +26mm was only 0.33333333333 of a mm out for wheelbase and being screw together could be sculpted with a large blunt file.  The chassis was far too short for the  Princess it should have been much more like 32mm X 30mm but it would never have hurtled round 12 inch curves at 200 mph with a scale wheelbase.  The same chassis ran under loco drive Britannias and WCs and some tender drive Brirannias as well

The old Hornby Dublo Wrenn 0-6-0T and 0-6-2T chassis had 26mm X 31mm wheelbase so two sets of their rods would make a set and the chassis could be re drilled to shorten the wheelbase.

[cookisan]

Thanks agian for the very useful info.

 

The model dimensions are very useful. I think what I need to do is bite the bullet and get some test pieces to have a go with!

 

Cheers.