David Andrews Princess – working on the frames

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Since my last post available time has been spent finishing tapping the horn guides, cutting the springs and hangers from the other side frame and then cutting out and modifying frame spacers.

Like most kits many of the provided frame spacers are either flat or L shaped plates. How ever there has been some attempt at replicating the actual frame spacers of the prototype albeit it in a very 2D form.

I have taken these 2D spacers and made then more 3D by adding framing to openings making them look a bit more like they do on the real thing. I still have some to go but this is a flavour of what I am aiming for.

David Andrews Princess Modified Frame Spacers

This model is also going to have the rudiments of inside motion. In so much as there is a large hole in the frames where the crossheads of the inside motion are quite visible. Due to the axles being telescopic I cannot fit a proper crank axle so what I plan is to use eccentrics to impart a small amount of motion to the crossheads/pistons giving some visible movement behind the frames.
Before moving ahead to assemble the frames I need to make a motion plate and cylinder front for these.
I started this by cleaning up the David Andrews cross heads and slide bars (I have a set of more detailed Griffin castings for the outside motion).

David Andrews Slide Bars and Cross Heads

For anyone who is planning on fitting outside or inside motion time spent fettling the parts to get them smooth running without any hint of hesitation will pay dividends when you come to assemble the various rods etc. to them.

The piston rods on the DA casting were tapered getting noticeably thicker at the crosshead end but reasonably straight. I have come across quite a few castings even from the better kits where piston rods have been like a banana. To remove the taper I put the end of the rods in my Dremel and making sure that it was rotating centrally I gently filed the crosshead end until the rods slid cleanly through the piston glands.

If you do this make sure that you don’t have the drill set on too high speed or the weight of the cross head spinning if slightly out of balance may bend the piston rod.