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Sunday, March 28, 2010

Birney Project ~ Window Glass II

Cutting, shaping, and installing widow glazing.

In part one of installing window glass, some of the brass sills were filed away so that I could model some of the windows open. Now that the car is detailed and painted, the "glass" can be installed.

Really the glass is .015 clear styrene. Cut to approximate size, I held it against the window openings and marked the location of the sills with a sharp blade.

Then I scribed in the location of the openings in the styrene (bottom), checked it against the model, and then cut out the openings (top).

A reader of this blog suggested using Micro Kristal Klear for gluing in the windows. Its a water soluble product, so it doesn't craze (fog) the plastic the way petroleum based glue would. I found this to be really easy to use.
Finally, strip styrene matching the dimensions of the brass window sills was painted the trim color, cut to size and glued into place.
And there we have it! The open windows add a lot of character and realism helping to make this car a real one-of-a-kind model. Yes sir! A real one-of-a-kind model!

Dandy

Monday, March 15, 2010

Birney Project ~ A Weighty Situation

Adding Weight to the Birney Car 

The weights I used are those kind that you see that come in a long strip with double sided sticky tape on one side. They are usually divided into sections that can be broken off anywhere at 1/4oz increments. They are usually available at your local model train shop for weighting freight and passenger cars to NMRA standards. I was able to fit 4 of these 1/4oz weights for a total of 1oz added weight.

Location of weights
1. Cut and fitted to clear the motor frame and filed to conform to the curve of the end of the car. Then epoxied into place under the floor.
2. Trimmed to fit under the roof in the sub roof cutout.
3. Filed to conform to the curve of the end of the car. Then epoxied into place under the floor.

Weights 1 & 3 had their double sided sticky tape removed so that they can be slid under the pilot. There they were epoxied in place. Here you can see where weight #1 was trimmed to clear the motor mount.

Weight #4 had to be fitted inside the front of the car. Yes, the car has a "front and rear" now. Originally it was designed to be double ended, but I ran into this problem. As you can see, Birney the motorman has been removed from the seat assemblies and is now fitted into the front of the car.
Weight #4 was notched to fit around Birney the motorman's seat.

The top of the weight had to be ground out to clear the headlight bulb and wires. Then it was painted black and glued into place.

After all that effort I was able to add an additional 1oz to the car bringing it to a total of just over 5oz. Doesn't sound like much but that is another 25% added to its weight. And the car is suprisingly heavy when you pick it up. Yes sir! Quiet heavy.

Dandy

Wednesday, March 10, 2010

Birney Project ~ Phun With Fysics

 After a test run on the Southern California Traction Clubs city modules, the drawbacks of single truck trolleys became apparent on ol' 301.

Sir Lord Dr. Isaac Nudeton Esq III PHD.

Nudeton's 3rd law of force states: "The force of the trolley pole pressing up against the overhead contact wire is equal and opposite to the force pressing down on the trolley car.". Who knew Nudeton was a trolley fan!
Well that force was evident on the Birney car. The pole pressing down on the back of the car coupled with the fact that there is a weight behind the decoder puts more force on the back wheels than the front wheels. So the back wheels become in effect, a fulcrum. In other words, the trolley wants to do a wheely.

And a trolley that wants to do a wheely doesn't want to take curves, it wants to keep going straight.

So the solution is: More weight in the front of the model, get those front wheels down so that the flanges will help the trolley get around corners.

So after making the bold statement of "There is officially no more room for anything else in this model!", I have to find more room for more weight in the front of the model. Yes sir! Have to find more room!

Dandy