New O gauge wheel sets

Osgood

Western Thunderer
Would I be right in thinking that at 7mm scale the normal shrinkage factor required for full-size casting is of no consequence - and therefore the same CAD moulding dimensions can be used whatever material is used for the actual casting?
 

Overseer

Western Thunderer
Would I be right in thinking that at 7mm scale the normal shrinkage factor required for full-size casting is of no consequence - and therefore the same CAD moulding dimensions can be used whatever material is used for the actual casting?
No, shrinkage needs to be allowed for. It can be even more complex because of the two casting stages - wax and metal. Different waxes have different shrinkage rates and are prone to warping. To achieve accurate size and shape the wax to be used and the casting metal need to be kept the same through the whole batch. The temperature of the metal at casting also makes a difference.
 

Axlebox

Active Member
I have been reading all these replies detailing where to insulate cast iron wheels and what type of pickup to use and I thought I would throw in my
two pennies worth.

I do not insulate the wheel or crankpin and fit after machining to a steel axle. I do however make a split insulated axles and also make
insulated axle boxes. current collection is made with two wires picking up from just two axle boxes from the front. The coupling rods serve to l
carry current to the leading wheels and Ohm meter reading are normally about 0.03 Ohms measured from the wheel rims to the collecting wires

The connecting rod is obviously connected to its crankpin and a small insulating Tufnal bush is fitted to the big end and a small brass bush fitted inside to connect it to the C/pin. The leading crank pin bush is counter bored to allow the attachment screw to be as flush with the outer edge of the coupling rod to make sure there is adequate clearance between the crosshead as the two parts approach each other. Also the leading axle needs to be accurately fitted with minimum side play to avoid shorting. A gap of between 0.010"-0.012" is sufficient.

If the loco has outside valve gear the return crank needs a small Tufnal bush; because it is very small it can run directly on the return crankpin.

To make these parts one does need the use of a lathe and a milling machine. Over the last 25 years I have also made various jigs to assist also.
 

Axlebox

Active Member
I also meant to mention that I fit compensation to the two leading axles on a 4-6-0. Also regarding the bogie or pony wheels I use split axles but I use small Tufnal bushes inserted in the wheel hubs.
 

Pencarrow

Western Thunderer
Steve,

I'm pushing forwards with the Bullieds in parallel with all my other wheels determined to get something out first 1/4 of this year. All the wheels will be available including bogie and tender.

Regards

Elliot

The Bulleid wheels on your opening thread page look great Elliot. Good news that you're pushing ahead with them as there are a few folk who recently bought the F7 kit.
 

Elliot 84A

Western Thunderer
I wish I knew you where there, I would have had a chat.

Len
Len, I'll be at other shows during the year, I was round on the guild stand demo'ing Solidworks and helping people with their questions regarding 3D modeling and rapid prototyping and getting peoples input on the wheels so I can tune them to the best kind of product to suit as many people as possible.

E.
 

Elliot 84A

Western Thunderer
Simply stunning, thats the best wheel set and crank axle I have ever seen.

Richard
Richard, thanks for that. They still need a little work but we're nearly there. I'm going to try and get as many individual wheels on display for the next show I'm at with hopefully something for everyone so any suggestions are always welcome.

E.
 

Elliot 84A

Western Thunderer
Will you be at Kettering this year, if so where will you be?

Len
Len,

I'd like to be but at the moment work is very hectic at the moment and trying to get these wheels up and running is taking a lot more of my time than I initially thought although I'm determined to see it through.

As for where I'll be I'm not sure. Yesterday I was on the Guild stand demo'ing Solidworks and helping answer peoples queries about 3D modeling and Rapid Prototyping. If the Guild want me back then I'd more than happy but I have to be mindful not to use it as a way to sell wheels (not that I am currently) as all the other traders have to pay to have stand and it would be completely unfair for me to do so.

E.
 

2-Bil

Western Thunderer
MAGNIFICO!
Wish (re Len C) id known too.Anything worthwhile ALWAYS takes longer to achieve as im sure any soul using this site knows full well.
Best Wishes for ALL your Endeavours
BW aka 2-Bil
PS to Warren
Saw the MOK Standard 4 tank (80016)in" the flesh"for the first time yesterday.The Lining looks even better than in the Photos, so heres a MAGNIFICO ! for you too.
adios
 

OzzyO

Western Thunderer
If you did a proper set of wheels for a L.M.S. Princess I could be very taken to part with some money, and that takes a bit of doing.

OzzyO.
 

Elliot 84A

Western Thunderer
If you did a proper set of wheels for a L.M.S. Princess I could be very taken to part with some money, and that takes a bit of doing.

OzzyO.
What's the difference between Duchess and Princess wheels? I'm a Western man so not that clued up on the "other" stuff lol.
 

OzzyO

Western Thunderer
What's the difference between Duchess and Princess wheels? I'm a Western man so not that clued up on the "other" stuff lol.

6'6" 20 spokes on the Princess, 6'9" 21 spokes on the Duchess. Slater's do a set of wheels for the Princess the 6'6" is OK but they have 21 spokes.

OzzyO.
 

Elliot 84A

Western Thunderer
6'6" 20 spokes on the Princess, 6'9" 21 spokes on the Duchess. Slater's do a set of wheels for the Princess the 6'6" is OK but they have 21 spokes.

OzzyO.
If you have a drawing I'm sure I could or are they identical to the Duchess in every other way, plus do you want Standard profile or Pro?
 
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