Morgan Hill Models Stock Car _ Design Evolution

[marc_reusser]

Over a year or so ago, Jon of Morgan Hill Models, and I got to talking about the possibility of a stock car kit. The idea was to use as many of the parts/designs/pieces from the existing line of car kits as possible, and then design whatever new parts would be needed.

The cars design would be "freelance", but based on prototypical design/construction methods/concepts wherever possible. It was to have character and some nice detail. We also discussed doing a pilot/test model with corrugated roofing, to make it a bit more unique/interesting.

For a while progress went fairly steady, but then with my freakish attention span and other things that come up in life progress got delayed.....but is now once again moving forward.

This thread will show/describe the evolution and process of the project to date...and as it progresses to its finished state.

Jon had sent me the parts from his kits, so that I could look them over, measure and work with them. Over several months, we had numerous design and idea exchanges/discussions. Based on the parts and discussions I set out to do some 2-D CAD drawings of the proposed stock car design. These are screen shots of the CAD drawings.








From these were developed a 3D CAD (SketchUp)model to show all the individual parts and an assembly diagram, to make sure everything would go together the way it was envisioned.






The base "flat car, side bracing, roof, roof bracing of the existing box car kit all worked for the proposed model, the end walls would however need to be new parts, and some infill braces for the laddrs/grab irons would also need to be added.

In the design process I did include some ideas/parts that would likely be an optional choice by the builder in a final kit, such as the draft timbers (which limit the truck swing, and radius the car can negotiate).

This is the assembled 3D model...still missing the doors, as these were/are still an item whose design was/is being discussed.












These are the laser cut bracing parts for the superstructure that come with the MHM box car kit. The stained pieces have been stained using BIS Silverwood, and brown & Grey Guache washes.




A view of an assembled side of the car. I left the bottom brace/piece in the door opening in place for several reasons; it gives me greater strength/stability to hangle the part during sanding, staining and assembly as well as keeping the piece from warping. (I will be modeling the doors closed,so I will be leaving the piece in place on my final model as well, as it will help me during assebly).




This is a view of the assembled new end bracing and sheathing. Though on a kit this would be a laser cut part, for ease and stability of construction on the test model, I built it using Styrene.




In order to get a smooth clean finish and get color into all the nooks and crannies, and sides of boards and bracing it was necessary to airbrush the model color on the exterior.

I decided to paint the sub assemblies seperately. The sides were laid flat on a piece of Friskit paper so as to avoid any overspray onto the areas to remain wood. Color is Floquil Oxide Red, using a 60/40 paint/thinner ratio.

The painted exterior and unpainted interior of the sides




Views of the car during assembly. The flat was assebled completely, then masked top and bottom, and the sides airbrushed. The Decking was stained in the same manner as the sides, Using BIS Silverwood, and washes of Brown and Grey Guache.








The next part was to appy the lase cut roof sheathing. As the car is a bit naroower than the MHM box car from which the part came (Due to the lack of the sheathing thickness of the box car sides), The pices were trimmed slightly narrower to give me the desired side overhang.(trimming was done along the edge that would be the seam at the peak).




This being my firts laser cut kit, I ran into some issues when staining the roof that it warped on me (as can be seen in the image above); so to make sure that it would not show any uneveness on the final model, I decided to add some additional lenth-wise bracing using stripwood.




Here you can se the roof pieces in place.....but I made a mistake...since I was goint to be doing a corrugated metal roof, I had wanted to face the laser cut boards to the interior of the car for added dtai....but in my concern/focus on getting the roof to lay absolutly flat, I wasn't paying attention to which side was up....and so this is the result.




Also visible on each of the corners and at the end is some of the unpainted "metal strap" detailing. This will later be "spot painted" with the airbrush.

Two additional design/aesthetic choices that I made that deviate from the standard components of the MHM kits, is the use of Foothil Model Works link & pin couplers, and scratchbuilt/adapted KD coupler boxes.




The other was the use/choice of Macleod ?NPC? trucks instead of the usual MacLeod ?Russel? trucks. For added detailing I added brake beams from Foothill Model Works.



These two views show the car during a recent test fit of the trucks, corrugated roofing material, roofwalk, and anchor board for the corrugated roofing.





The next steps, and in progress, are adding the truss rods and brake rigging to the underside, then applying the roofing and roof details, as well as misc. other detailing on the car side. Lastly will be the addition of the brake wheel and it's mounting hardware. The doors style is still in question/under consideration.


Marc

[Chuck Doan]

Good planning equales good result. A very plausable looking car, Marc. And very nice construction of same.
Those grabirons...what source?

Chuck

[marc_reusser]

Thanks Chuck,

Some of the grab Irons were supplied by Jon...so I am not sure .....but I also used PSC ones which were identical.

A note when using these....they are EXTREMELY fragile when being removed from the sprue, and there is an easy 50%+ attrition rate, where they break in the middle. I was able to alleviate some of this problem by running a brush of MEK (Plastruct Solvent) across/along the grab iron to glue/seal any hairline fractures that were there that would otherwise cause the part to berak in half. I do the MEK one more time after the grab irons are in place on the car, beacuse there is sometimes tension put on the grab iron if the holes are not absolutely perfectly frilled/aligned etc...or if the GI was slightly wracked when pushed into it's holes....the MEK afterward helps slightly soften the plastic, just enough to allow any tension to dissipate.

Marc

[Doug H.]

Marc,

Nice crisp car. I guess I'll be the odd man out regarding the grab irons. Isn't a real grab iron only 5/8" in diameter? While I do like the formed ends, they really do look too thick and clunky to me. Also, do you have any idea about what brake and door hardware will be used? Details like the car hardware can make or break a model.

Thanks,

Doug

[marc_reusser]

Doug,

I have no idea how big a dia they are on the real cars, but I agree that the grab irons are a bit chunky/heavy....they scale out to .020-.022".....so about 1" to 1-1/8"; but short of having the modeler make his own, they are the best that I have found on the market.  There used to be some nice thin PSC brass castings.........but they have gone the way of many of the rest of the PSC castings....missaligned blobby brass shapes that have only a slight remblance to what it's supposed to be....they might as well be Kemtron or Dave Braun castings.

The brake hardware will be the non-airbrake setup that comes with the MHM kit line.....for the wheel I am using the FMW one...but the kit will likely include a PSC one....the staff and staff mounting hardware are from the PSC line...either their Boxcar or Low Gon set. I had considered doing a "brake platform" on the car end like many South American cars had...but it was decided that it would just complicate matters....and could easily be done by an individual modeler wanting to do so.


Marc

[morgan Hill models]

I would like to thank marc for all his efforts to date with this pilot model. I had originally asked Marc if he could use some of the components from my boxcar kit and come up with a stockcar. A few days later I received the beautiful set of drawings and 3-D concepts shown above. He just recently sent the photos of the actual model...Wow! I was very pleased! I just need to turn all the data into a kit.
The grab irons Marc used are from PSC #5642. As Marc mentioned they are very fragile, and a bit oversized. For those  reasons I will be using wire ones from Tichy #2001 18" straight and #2002 18" drop with macleod Western N-46 grab iron NBW's. I try to use as many detail parts as I can from Doug Macleod, His parts are top quality and he delivers quickly. He has 3 brake wheels, I like the 15" for these small cars. Jerry at Foothill Model works is continuing to add to their line of details and are worth consideration as well. Both companies specialize in western narrow gauge from which these cars get their "flavor"
Thanks,
Jon
www.morganhillmodels.com

[marc_reusser]

A quick peek at the final model. I think Jon will have it with him at O-Scale west.

I can post some more pics as soon as I resize them from their current 12MB size.

Marc

[TRAINS1941]

Marc

Just an outstanding job on the car.  I just emailed Jon last week to ask him when he thought it would be coming out.  After seeing the job you have done on this I can't wait to get one from Morgan Hill Models.
As always Marc you never cease to amaze me.

Jerry