The limits of brass casting

[Hawk]

I am in the process of designing some masters for fittings that are to be used on an 0-scale mineral wagon.

Here are a screen-dump of the masters at their present state:



Is it at all possible to cast such fairly long and slim parts in brass? The cross section of the parts are 1,4 mm X 0,4 mm. The longest one is around 30 mm long.

I would guess that the arrangement of filling funnels and escape channels for trapped air is fairly important. Tips on designing those are also much appreciated!

 

(The printability of the parts in wax is another issue, but that is a topic for another forum!)
 

[Pete Harvey]

Yes very possible the brake pull rods on my 7mm KFA Wagon Kit are 200mm long and cast in brass.

 

Pete

[hobbyhorse]

Same as Pete said, we do a lot of thin items at Hobbyhorse one being some dummy 7mm fish plates with a thickness of .30mm. Allowing a generous sprue we find with small items helps.

 

Simon

[Hawk]

I have now received a batch of parts from an American caster, Dave Sciacca of Valley Brass & Bronze. You can find his contact info here: http://www.tracksidedetails.com
He found it challenging to shoot the waxes, but reported no difficulties with the actual castings. 
 
The original master was a wax print from Prescision Wax in England. As I understand it, going directly from a wax part to a RTV mould, but in this case it seems to have worked just fine. 
 
I have tried printing the master with several printers, but the best print was definitively the wax print made by Prescision Wax on a Solidscape printer. The only alternative seems to be prints by Fineline in the US, but this would have costed at least USD 168 (excluding postage) compared to the GBP 24,- (Including postage to the US).
 
Here are some images:

 

 

A thread about the woodwork for the wagon can be found here.