Thursday, 12 February 2015

Investment in modelmaking...

A dreadfully serious sounding title for a simple aspect of modelmaking, albeit an essential one.

When building some shapes and fiddly structures, it is so much easier to pile in the materials, so that they are easier to assemble and then cut and trim the excess, effectively wasting or "investing" some material into the bits pot.
The alternative is to cut the individual parts to size and hope you can hold them all in place whilst soldering.  I am NOT saying you can't do it that way, but as I have to earn my living from these endeavours, I can't afford the hit and miss nature of that method.  So, I'll always work on the principle that it's easier to remove than to add.

Whilst making a new undercarriage master for the Pilatus PC12 master, I decided that though an early white metal nose leg was very acceptable, the earlier main legs were not at all nice and were way oversized, so had to be completely replaced with new brass ones.  The legs were handed, so two had to be made.
Here's the new legs. One finished tother day, but one done today.  Note how the long stick of brass rod is left attached to the bent part, soldered onto the end of the main leg's articulated member.
The leg on the right has the brass rod trimmed to rough length.  Rough, because we still have set up the position of the wheel and tyre combo.

Here are the two new ones with the old w/m one showing the hefty, unsuitable nature of it.  And that's with a big overscale chunk already cleaved off it.

Now, obviously the left over brass is still usable on other projects, but bits of all the rod used will have been clipped off and pinged away.  What gets caught, goes back in the bits pot and it's amazing how many of those bits get used eventually.

The main leg coming down from the fixing plate (about 7x2mm) could have been soldered straight on to the plate, but that would have been another pain to do, so holes were drilled in the two plates.  One for the 1/16th" diameter main leg and one for the 1mm bracing leg.
A small investment in 1/16" enabled that to be held in the vice jaws by putting a slight crank in it, so that a bit is in the jaws and another bit is parallel to the jaws, enabling the plate to sit on the jaws and be soldered to both main leg and brace at one sitting.  When happy with the solder clean-up, still on the brass rod, to enable easy clean up, the rod is finally clipped off, above and below the plates.  So you've invested in a bit of 1/16th" rod which now has a slight crank in it, but that can be straightened in the vice anyway.
Time-wise?  The second leg was assembled with solder as my wife called to say she'd made coffee.  I am still drinking that perfectly hot coffee as I type!

Invest in your cheap materials, not your own time.


  1. Intresting. I suspect many of us make life harder for ourselves

  2. Indeed, James, but I hope the only time I do it after all these years is when I need a particular tool from the distant shed on a wet day and I make do with something else, almost always with a time penalty.