1920 MacDonald Model O, 5-Ton, Low-Bed Truck

[LeOn3]

Russ,

Is it still possible to order the December Modellers' Annual?

I like to try the techniques I see in the pictures in this forum, so that I can improve my models on my little exhibition layout. And maybe put some pictures here.

Leon

[TRAINS1941]

Russ

Just was kidding you, thought maybe all the people that I know, that say there is no book out there on how to do things would take notice when there here.

Jerry

[finescalerr]

Leon, sorry, but once my printer sends out the books, that's it. I long ago realized the back issue business is unprofitable and got out of it. We have nothing here. A few books may remain in hobby shops; you would have to search for one. Maybe our hobby shop distributor, Kalmbach, might have an idea or even a book lying around the office. Another possibility would be to see whether somebody might photocopy all or part of a book.

Jerry, I was almost certain you were kidding. Even so, go stand in the corner. And no peeking over your shoulder.

Russ

[Belg]

And Jerry make sure you put on that pointy paper hat while your in that corner!! Pat

[Scratchman]

This finishes up the frame and wheels, and it's nice to have the model to this point. There is another frame, that the rest of the truck sits on. This frame sits above the front frame and is attached to the four springs. I will start the next section with this frame and the differential, along with the four contact points to the four springs.I will still talk a little bit about the wheel construction, later on.

Gordon Birrell

[finescalerr]

Way to go, Gordon. -- Russ

[Chuck Doan]

This is Master building...whatever you need, you make it!

[Franck Tavernier]

Outstanding Gordon! 

Franck

[Scratchman]

The prototype wheels are very complex castings and would be very time consuming, so my wheels for this truck needed to be a little more simple.

The Rim

For these wheels, the main tool I use is a two-inch outside-diameter piece of  Plastruct round tubing (TB-200). I will  use this  as a  form for the two .030" strips of styrene as I use hot water to shape it, and  hold the shape when gluing.

1- Out of .030 sheet styrene, cut two 7/8 inch wide strips for the rear wheels and two 3/4 inch wide strips for the front wheel. One long enough to go around the tube and one long enough to go around the tube and the first strip. Cut these strips longer than the needed length, these well be cut to the correct size after the strip has been formed.

2- Pull the strips though your thumb and finger to start the curve, and place both strips around the tube and hold in place with rubber bands. Place in a glass bowl and cover with hot water and let set tell water has cooled. Remove from tube and cut to length. Now place the two strips back on the tube and glue together staggering the joint 180 degrees apart, being careful not to glue it to the tube. I use a liquid plastic cement.

The Center Disk

1- Cut a two-inch diameter disk out of .030" styrene. I use a good quality compass with a metal tips on both points. Drill a small hole in the center to help hold the tip in place. You need to go round and round many times from both sides, break it out when you get a good score and sand the disk to size.

2- I start by drawing a six-inch circle with a two-inch circle inside that circle on a piece of paper. I use a protractor to mark the segments on the six inch circle. The front wheels are divided into ten spaces and the rear wheels are divided into nine spaces. Draw the lines from center to the outside of the six-inch circle.

3- Place the styrene disk on the drawing and add the lines for the spokes. draw a one inch circle to both sides of the disk.

4- Add three layers to the out side of the disk.

a. Add a one-inch outside-diameter exchanger ring from Plastruct (RI-32) with .188" x .100" x 1/2" long strips of styrene (cut out the spaces between the spokes on the disk.)

b. On top of the exchanger ring add a one-inch diameter button.

c. And on top of that I used some cone shape parts out of my junk box.

5- On the inside of the disk after enlarging the center hole to 1/8" add one or two 1/4" scale Grandt Line circus wagon wheel (#30 or 31), the one that is one-inch diameter. This will give a good solid hole for the axle.

Place this assembly inside the rim and add a thin slice of the two-inch round tubing one on each side of the disk.

The Hard Rubber Tires

For the hard rubber tires cut a slice 3/4" wide for the rear wheel, and two 5/16" wide for the front wheel out of two-inch ABS pipe. This is inside-diameter and will not fit over the rim, so I cut it in one place and added a short segment to get to the right size.

I have added a photo showing some of the parts.

Gordon Birrell
http://www.flickr.com/photos/77318580@N00/

[JohnJ]

Gordon:  Another great one.  BTW, you didn't send me the links we talked about yet.  John

[Scratchman]

Thanks John, good to see you on this forum. There is a lot of good stuff over here. I sent you a PM over at Railroad Line forum,for the links.

Gordon Birrell   

[Scratchman]

This model was starting to kick my butt, not being able to see what is going on with some items in spots, til I found these pics of a 1922 model A MacDonald 5 ton truck today.

http://www.google.com/url?sa=U&start=1&q=http://rockindownthehighway.blogspot.com/2007/09/rockin-birthday-visit-to-hays-truck.html&usg=AFQjCNFU4rVKBv6JPCmoKsUaKPSq0OTUkg

Gordon Birrell

[finescalerr]

I can see where the photos might have been rather helpful, Gordon. Even without them your model is really exquisite so far. -- Russ

[Scratchman]

I've got the upper frame with the engine bottom, transmission and differential in place, and this full assembly mounted on the lower frame. There are still the assemblies that go between the sprockets and the rest of the steering assembly to finish up before moving on to the radiator hood and the rest of the engine detail. The cab is mostly finished and snaps on to the upper frame.

Gordon

http://www.flickr.com/photos/77318580@N00/

[finescalerr]

Gordon, did it ever occur to you that you're an artist masquerading as a model builder? -- Russ