Tuesday, April 07, 2015

Bracing joints

Braced parts2Zap superglue is marvellous stuff but like all such glues, there are times when the mechanical joint isn't as strong as you would like.

A good example is on the back of Nellie, where the cab back meets the footplate. The are of join isn't very large but the chances of catching the component with an errant hand are pretty large.

Add to this the lever effect on the join and you can spot the potential for trouble.

Fortunately, resin is easy to drill so I popped a hole through the bottom of the cab back and into the footplate. A length of brass wire was glued in to this and cut off with flush cutters.

Not being able to get the cutters in to the cab properly, there was a small remaining stub. This was dealt with using a curved file called a riffler. This can be poked in to small spaces and manipulated to file away the excess metal.

Braced parts1The dome provided an interesting problem. The cartoon loco didn't have to worry about the niceties of actually working, so Emett could draw a ball balancing improbably on a point.

Real life means the dome is make up of two castings that have to be joined. With such a tiny contact area, only drilling both parts for a thin wire and using this to join them can work.

The ball was drilled by eye and wasn't too bad. A little bending of the wire ensured the parts are in line.

2 comments:

Anonymous said...

Phil,

I notice that your pushing on with the Emmett loco, but seem to have abandoned the GWR railcar again. Is it proving a difficult build?

Colin Murdoch

Phil Parker said...

As I mentioend a few days ago, I'm having trouble with the railcar valve gear. However, I picked up some new parts at the weekend, so all I need is a little bit of time...