To paraphrase Vane Jones, "Knowledge is of little value until shared with others."

Monday, March 30, 2015

Finishing a CTM 4000 Baldie Kit Part 4: More Roof Vents, and Miscellenous Details

Intake Vents
Thinking of how to add the 2 small square vents built into the roof of the prototype took some time. First something already available was looked for.
Nothing could be found.

These vents were built into the roof. They are louvers which blocked objects falling from above from entering the duct. At this end (#1) of the car, an electric intake fan in the ceiling of the entrance/exit vestibule pulled air from the outside through the 2 vents and into the car. The 2 vents near the center of the car were passive exhaust vents.

After much thought a square vent 0.010" thick was built out of styrene. Styrene 0.010" thick is flexible enough to conform to the contours of the roof. This same type of vent could be made from etched 0.005" or 0.010" brass. I do not know of anyone who etches brass so the styrene vent was made.

Now that my roof is finished, I feel my measurements were a little bit off. Therefore as we go through this section, my comments about measurements will reflect this.

First a square had to be built from 0.010" x 0.020" styrene strips. Using my concept of if 2 opposite corners of a square or rectangle (1/2 of a larger square being made) are square then the shape is square. The photos go through the building process.

Eight pieces of 0.010" x 0.020" styrene were cut and glued together at 90 degree angles. Each piece of styrene was cut longer than required. A small machinist's square block was used to ensure each joint was square. Small amounts of styrene glue was used. Too much would warp and/or dissolve the styrene strips.

After each of the joints had completely dried, they were prepared to be glued into squares. Notice the penciled lines on 2 of the 1/2 squares. These are the final size of the complete square.

The red and green arrows point to the pencil marks. The blue area points to an area where too much styrene glue had been used. The styrene dissolved to provide the webbing effect.

The next steps were to make the squares. The photo taken below shows the process just after one of the sides was cut short. BTW - all cuts in the making of the squares is at 45 degrees to allow the square to lay flat. Small drops of styrene glue were used.
IMPORTANT - Leave one arm attached to the box (green arrow).
 
You need the one arm on the styrene square for the installation of the louvers. Four louvers need to be installed leaving 5 slots for the air to enter the car. The louvers are 0.015" x 0.020" styrene cut to the correct length to fit into the square.
 
The louvers are placed on their 0.015" side which means they will be sticking out of the square. After all the louvers are installed, they will be sanded down to 0.010" thickness.
 
Use the handle to hold the styrene square against the glass as each louver is installed and glued in place. Dentist scrappers and other picks are useful in cleaning up the vents.
 
This is a close-up of one of the vents after gluing and sanding. Notice how the glue has softened the styrene. At this point the styrene is stuck to the glass. It can be cleaned up plus the handle cut off. Gently use a new razor blade to remove the vent from the glass.

Handle the vents carefully. Now the vents have to be glued onto the roof. These vents are located at the #1 end of the car above the side door on each side. Glue the bottom of the vent 1st.

Then after the glue has set, continue gluing the vent around the curve of the roof. Be sure to glue each slat of the vent to the roof. The vent will be sanded and you do not want any of the slats to come loose.
The vent has been completely glued to the roof. The vent can be gently sanded to even out the vent plus reduce the slat size. Remember they were 0.015" sticking out (0.005" higher than the 0.010" thick vent material) from the roof.

Next comes the old auto body or if you prefer the old plasterers' trick. Many years ago we hired a pair of plasterers to repair some cracks etc. in a wall we had in our home. After the work was done I commented to one of them about how nice and flat the finished wall looked. He told me the wall really isn't flat but an allusion of looking flat. The trick was to make the wall look as smooth and finished as possible over the long flat plane of the wall.

I've repaired the body of an old car (1953 Porsche) with "bondo". The idea was not so much to match the curve of the other side of the car as much as to make the side being repaired look like a smooth and finish curve without holes or cracks. This was much the same as the plaster work in our home.

The intake vents on the roofs of the prototype 4000's were into the material of the roof. The vent did not stuck out from the roof. On the model the same thing has to be done. Squadron body filling putty is applied around the vent and allowed to dry. Do not use an old tube of Squadron putty. It will not flow well and will dry with cracks and small holes in it.

Apply the body putty up to the center of the roof, for 1/2" to 3/4" towards the center of the car, down to the bottom of the roof, and all the way towards the front of the car.

Squadron body putty actually dries to hardness. As the solvent evaporates the coating of putty with shrivel up. Thin coats will dry quickly and not crack. Thick coats with shrink in and crack!

It's best to wet sand (320 or finer grit) the vent and body putty until the area is smooth without cracks or holes. Clean out the slats in the vents. If the edges are not feathered and/or there are cracks or holes apply more body putty. When dry wet sand again. Clean out the slats in the vents.

Repeat the cycles of application and sanding until the area looks smooth and finished. At this time you'll notice the vent to appear as though it's into the material of the roof. The slight "bump" of the vent will be un-noticeable.
This is the vent during the sanding process. The rivet decal had been prematurely applied to the roof. Photos which are cropped and the size readjusted are great to show the imperfections in a model. The lines were drawn to be sure the slat holes were the same length.
 
More work of filling in the cracks etc. had to be done to the vent in the above photo before the rain gutter and rivets were re applied. Unfortunately I failed to take enough photos of the work.

This post is getting long and there's still the rain gutters, roof rivets, and something strange about the roof! The next post will have to cover them.

Cheers,
Ed




Wednesday, March 18, 2015

Finishing a CTM 4000 Baldie Kit Part 3: Underbody and Odd Boxy Roof Vents

Underbody
Do you have your photos of the prototype Baldie you are planning on building ready? You'll need them for this part of the assembly. First, the floor was attached to the body with 2-56 flat head screws the same as the Plushie model.

If you are making a powered Baldie, the same Q-Car underbody kit as the Plushie can be used to supply all the needed parts.

If your Baldie is to be unpowered, many of the same parts are needed. It's the electrical control parts which are not needed. I used the diagram with part numbers supplied by Q-Car in the Plushie underbody kit to order all the parts needed.

Some of the electrical control parts which are needed besides the air brake parts are the 4 MU connectors at the car's corners and the battery box. BTW - If you are not aware, the 4 MU connectors at the 4 corners are for the door opening/closing controls and not the MU operation of the cars in a train! The MU connectors as well as the 600 v buss are located below the couplers.

This is where I started to have 2nd thoughts about not having a more detailed underbody on the cars. Since the cars would be operating on elevated right-of-way, it may be possible to see the underside of the cars. If this is possible then a more detailed underbody is called for.

To assuage my conscious the brake rigging from the brake cylinder to the trucks was added. The coupling at the end of the brake levers had to be drilled out to receive the brake rigging to the trucks. While there is a dimple in the soft metal, the soft metal casting was not the best. The drill would not stay in the center of the coupling.

A "tool" made up of 2 pieces of brass tubing was made. The drawing below will give you an ideas as to how it works. Sometimes more than 2 pieces of tubing are required to make-up the inner piece to get the correct diameter of the pieces to be drilled. Styrene tubing can also be used.
If you want to save the tool for future work the pieces of brass tubing can be soldered together.

When using the tool be sure the drilling is square with the piece to be drilled. My drill slipped towards one side. But, all was not lost. Do not rush; work slowly!

This is what the underbody looks like for my Baldie after 0.028" diameter brass wire was glued in place for the brake rigging.
Green Arrow = where CA was used to attach the end of the brake rigging to the body
Red Arrow = the original location of the battery box. After looking at a photo the location of the box was closer to the side of the car.
Blue Arrow = location of a filed out line in the floor used to indicate the #1 end of the car. The piece of styrene (glued to the door on the model) used to hold the floor in place has a similar filed out area.
Orange Arrow = metal washer glued to the styrene body bolster. The metal washer provides a better bearing surface between the body and truck.
 
The brake rigging was just glued to the bottom of the car. This is one solution for having the brake rigging hanging loose under the car. Normally the brake rigging is attached to each truck. Since this is a model without operational brakes and trucks which are free to rotate, what is done to the brake rigging is up to the modeler.
 
Gluing the brake rigging to the floor may not be the best solution. The brake rigging ends up going up to the floor at an angle which would never be seen this way on a prototype car. In a future post the brake rigging on the Plushie will be hung in a different manner.
 
Also, I like to be able to solder the brake rigging to the levers of the brake cylinder. I wish I had replaced the brake cylinders with brass castings.

The body bolsters for the trucks were installed. For the 6'6" wheelbase truck an old Wagner un-powered truck was used. The wheel set was changed to a set with 0.145" thread wheels from NWSL.

Just 4 days ago I found a 5'6" wheelbase truck. The wheels need to be changed to NWSL wheelsets.

Exhaust Vents
Now comes one of the items all of you have been waiting for - the roof vents! In looking at photos of Baldies there looks like of the original batch, the trailers, starting with number 4001 up to a number unknown to me, a Utility exhaust vent was applied to the roofs of the cars.

Again, starting with some number I am not aware of, a strange looking boxy vent was applied to the roofs. In looking at the photo of the car I desire to model. It had the strange boxy vents on the roof.

Just in case you were not aware, vents were not usually make by the car manufacturers. There were small sheet metal shops which specialized in making objects out of sheet metal. They made vents for railroad cars, duct work, plenums, and other boxy looking objects. Utility, Globe, Garland, and Ward were some of the manufacturers of vents.

If your car needs Utility vents, the Q-Car CS016 or CS021 can be used. CTM, Terry, will have a Utility vent available.

Looking through as many photos as possible I noticed some odd, at least odd to me, things about the vents on what was to be my car. These include:
     the side nearest the center of the car and 2 sides of the vent were solid,
     the side facing the outside of the car while solid was open at the edges,
     the 2 sides facing the center of the car and outward were parallel to the sides of the car,
     the vent hugged the roof line of the car, 
     the roof of the vent followed the contour of the roof.
     the vent was almost square, and
     the sheet metal of the roof over hanged the sides.

No one makes a model vent like this! CTM is not making a vent to match this design. The 2 vents will have to be scratch built.

Time for a "time-out" - I've reached a point where there is something I have never seen before. Yes, during the time I rode both Baldies and Plushies, this type of vent may have been on the roof of the Baldies I rode. I've never noticed the vents before. There are only photos of the strange boxy vent available to me. Therefore the dimensions will be a SWAG (Silly Wild Ass Guess).

This series of photos is how I located and scratch built the vents.

The vents are positioned so 1 side of the vent is centered between 2 windows on the side of the car. A Q-Car CS021 vent was used as the base of the vents. Two of the CS021 vents were installed on the roof. 
Using 2 machinists' squares up against the sides and a ruler, the center of the roof was found. This has to be done twice, once at each end of the car.

The center line was drawn down the center of the roof.

The short line to the left is the side of the vent centered between 2 windows. The line of the right is the center line of the vent casting to be used. The inverted "T" is where the hole has to be drilled.
 
The Q-Car Co. vent was glued in place. Then I found the side of the vent facing the center line was too low. A piece of styrene of the correct size was attached to the top to correct the incorrect measurement.

The Q-Car vent is too high at one end. This end was filed down so as to be below the required profile.
 
To make vents which have the correct side profile, vents were drawn on a drawing of the roof profile of a Baldie I had. The profiles were then printed on card stock (maybe 80 lbs., 8-1/2" x 11" stock). After the profiles were printed and cut out, each piece of card stock was impregnated with CA adhesive. CA was applied and wiped off.
If you are able to print out this photo so the actual dimension of each roof profile is 2" actual inches each, you can make your own vent side pieces.
 
Do not toss out any of the car stock as this will provide more than enough material for the other parts of the vents.
The sides of the vent are glued on.

The top side is glued on.

The bottom side is glued on. Notice it's pushed in a little bit.

Blue tape was placed on both side of the vent to sand it. The blue tape protected the finish of the roof during the sanding process.

The body of the vent was filled in with white body putty and sanded on drying.

Finally (Unfortunately no photos were taken of this part of finishing the vent.) a piece of the card stock was glued over the top of the vent. If needed it can be sanded to shape.

Both of the odd boxy vents should be built at the same time.

The 2 vents on both sides of the roof at the #1 end are next. They will be built and installed in the next post.

Cheers,
Ed