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Dear Members!

I am currently trying my luck on two of Ted Schnepf's fabulous stock car kits. This is (again) the first time to work with that material and I would like to address some questions here.

1) How do you get your parts straight? I read about boiling in hot water and indeed that softened the castings up. Once they cooled on the super flat kitchen worktop they had a tendency to regain the original warp. I used weights while cooling - resin was not impressed. 

I read in the Andrews Trucks topic (Thanks to OSCALETRAINS!) that it takes a long time to "weight the parts straight". I do so but so far I can not see any progress. The curve in the parts is not really a problem when using some supporting angles and jigs for mounting. I decided to glue the parts together and it worked out just fine. 

This poor woman's jig helped to glue the floor in the right position. Does the material really straight out when weighted just long enough? Thanks for your help! :-)

Sarah

S

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From my experience, warped castings in flat unbuilt resin kits come from a number of different circumstances. Removing the casting from being captive in the rubber mold weighted down with a flat plate on the open side before they cure totally rigid can allow some warpage to occur, even when placed on a flat surface to cure.  The resin doesn't really fully cure a lot of times for up to a week, depending on the resin, humidity, accuracy of mixing the two components before pouring, etc. Some tooling resins shrink a lot.  Other urethane consumer type resins also shrink more than others, usually the faster the cure time the more shrinkage the casting will see. This is thousanths of an inch per inch of length, which in HO scale is not too serious but because O scale castings have far more mass and are usually much longer, it can become a real issue.  Castings that are open poured which are not then covered and weighted down to cure will almost always eventually bow in both directions over time, I don't know why that matters but it seems to. All resins shrink to some extent, but the ones with high shrink rates will also noticably shrink on the side of the casting that has the most detail in all directions to the point that it pulls the casting bow shaped in both directions from the other side. These are virtually impossible to fix and use to build a model with. It's a good idea to drill a really small hole in the middle of the bottom of the floor of your model, since even after building it up into a box, the castings will degass to some extent for a long time, especially if they get warmer, and if there is no place for the gas to escape, the thinnest castings in the car will begin to bow outward from the pressure and be ruined(obviously not an issue with a stock car). The WORST thing you can do with a built up resin car or kit is to place it in direct sunlight, or leave it in a hot car interior.  ABS plastic will tolerate this pretty well but not cast resin.

That said, the resin the CB&Q stock cars were cast with seems pretty soft in its finished state. I just left mine on a flat surface for a month or so and they went back flat.

Last edited by oscaletrains

Oh, I should add to this, as soon as you purchase a flat resin kit, you should take the parts and lay them on their flat side on something flat. Leaving them for long periods of time jumbled up in the box or worse, being pushed on by other parts in the box, can and will lead to warped castings when you go to use them down the road. Or you could cut some flat plywood or plexiglass and rubber band them to it and put them back in their box standing upright(on edge), this will keep them pretty straight.

TexasSP posted:

I have no experience with these kits, but some with resin and plastic kits in general.  Most likely the boiling water is not getting the parts hot enough to relieve the internal stress which caused the warping.  Maybe try in a steam basket.  If that doesn't work try the oven:

Steam is certainly hotter than boiling water, might work.  I'd be REAL leery about using an oven.  One of the two sides of urethane resin is pretty nasty stuff, especially if inhaled. I'd be afraid of the fumes that an oven might produce when heating urethane castings. The cured product is pretty safe, with the dust you get from it by sanding or whatever not really dangerous. If the sanding process produces enough heat to make it smoke though, breathing that might not be.

I also have some epoxy resin cars of old, and a couple of them seem to be "leaking" a brownish colored liquid in a couple places. From what I understand, this is the resin portion of the two part mixture that was not mixed with the activator well enough when cast and is "venting".  Glad they are not painted yet. I plan to clean it off with solvent and then spray the car with sealer before painting in the hopes it will block it. Maybe it will leak into the interior of the car then, I don't know.

Thank you for all the comments! Now I'll go downstairs and make sure to re-pack other kits. Thanks TEXASSP, that's a good point! I'll try different kinds of heat to some parts that I don't include in the kit. Very nice models, Erik! So after six of these you really know how it's done :-)

O.K. Here comes question two: How do you prepare the material for painting? Is a brush wash with soapy water sufficient? Do you recommend a certain primer?

Thanks in advance!

Sarah posted:

Thank you for all the comments! Now I'll go downstairs and make sure to re-pack other kits. Thanks TEXASSP, that's a good point! I'll try different kinds of heat to some parts that I don't include in the kit. Very nice models, Erik! So after six of these you really know how it's done :-)

O.K. Here comes question two: How do you prepare the material for painting? Is a brush wash with soapy water sufficient? Do you recommend a certain primer?

Thanks in advance!

That's a tricky question.  It depends on what, if any, mold release the caster used when he made the parts. If no mold release was used, then the parts will have silicone on them that wicked out of the RTV mold and will fisheye when painted. If the caster used an mek based primer on them(like the early Raills Unlimited car bodies) they are preprimed and ready to paint. If the caster used most any other mold release, some of it will be left on the castings and may or may not cause an issue. You can use different sorts of cleaners on them, 409, Fantastic, etc. Some people have used oven cleaners. Washing with dish washing soap is probably what most people do unless they just prime and paint them and hope for the best.

My stock car showed a little fish eye when I painted the insides, so I will spray some 409 on them, rub a toothbrush on them(not my current one though) and rinse them off and let them dry before doing the car itself.

If you intend to spray primer on them for a first coat, which is probably a good idea since the car will be part resin, part plastic, part brass details probably, then any good name brand model primer will work and not hide detail. Model Master Fine primer is nice, but laquer based so be careful on ABS plastic. Tamiya makes an excellent rattle can gray primer as does Testors. These are all made for the scale plastic model crowd and are really fine particle paints.

Last edited by oscaletrains
Sarah posted:

O.K. Here comes question two: How do you prepare the material for painting? Is a brush wash with soapy water sufficient? Do you recommend a certain primer?

Thanks in advance!

Depends on the resin and who did the casting. If they used a mold release, possibly silicone in nature, most recommend in their instructions the warm soapy water and scrub brush step, although that really should not impact a silicone based agent.  Mineral spirits would be more effective.

This is why I rarely bother to use a mold release agent......

Primer - 2 schools of thought - 1 - use a basic primer of general grey color so it's easier to paint over or -2- just put a first coat of whatever color you plan on using and call that the primer

I would be leery of the oven as I had a baking oven made for drying paint on models and even with the oven cracked partly open it warped the heck out of a resin passenger cars.  I would try the weight method and perhaps adding some heat to speed the process.  Perhaps a heat lamp focused on it or a heating pad under or on top allowing the heat to soak thru while the weights do there work.

 

VGN64 posted:

I would be leery of the oven as I had a baking oven made for drying paint on models and even with the oven cracked partly open it warped the heck out of a resin passenger cars.  I would try the weight method and perhaps adding some heat to speed the process.  Perhaps a heat lamp focused on it or a heating pad under or on top allowing the heat to soak thru while the weights do there work.

 

We have all either seen the results or heard the stories of those unfortunate modelers that baked the paint on their models so well that the solder melted and the model turned into a pile of parts.  I've baked my share of Scalecoat paint on models and never had that happen, though I never let the heat go over 200 degrees.  For resin it'd have to be a very precisely controlled oven. But some people who cast resin do indeed use an oven to cure the castings faster. I have no idea the temperatures to use for that but I imagine it is pretty low.

I don`t recommend an oven for flattening resin parts. Too hard to control the temp and disaster is a possibility. I have had good luck with a heat gun set on low and a few weights. Of course you have to be paying attention and start with light passes. Especially with thin stock car sides. I use a right angle piece of stock brass glued inside along the top of the car side to straighten and strengthen it. Also gives a larger surface to attach the roof to.  jefferson

Erik:  Like the almost full stock train.  As a Burlington enthusiast, you might get a kick out of a tale I read in "Classic Trains" regarding a "Burlington Livestock Express" in the mid-50's.  A photographer was out in Sandwich, IL photographing steam powered trains, occurring in the Fall seasonal rush. He saw a headlight down the line, eastbound, and moved his car over the crossing to get into position for a photo on the other side of the right-of-way.  Thinking he had a comfortable cushion of time, was shocked when the train slammed by him at Zephyr-like speed. He just barely caught a glimpse of a number on the cab side.........in the 3's.  This was an all-live stock extra, pulled by a Hudson.  The Q had the right locomotive for an "express" !!

Thank you, Erik. Great Picture!

Meanwhile I have the right Andrews trucks, a big "Thank You" goes to Jay Criswell for providing these. By luck even the riding hight matches the standards and without shimming. I just needed an ultra thin washer to clear the center plate bolts. 

Also found the right primer. I made some tests with products for plastic models, such as Valejo plyurethane primer with a water like lotus effect. Next product was Autoborne Sealer and it turned out to be a very good base for the color. I only primed the inside of the car, can't get there later. I might leave it grey instead of brown. 

Next steps:

* Finding a herd. Somewhere I've seen that a smart modeler put a couple of styrofoam sheeps in a stock car and it looked very convincing. Lighting will come from above on the layout so I don't have to bee too accurate I guess. Advice welcome :-)

* Adding electrical wipers to the second car's trucks and doing all the wiring for a tsunami sound car. I really want that! 

https://www.youtube.com/watch?v=CzKk-6V23Qg

And Jay – I promise not to ever grow up *smile*

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Well, virtually all roads had stock cars. Unfortunately, not very many of them were exactly the same as other roads had. The Mather lease fleet cars wore different road lettering.  I am sure there are modelers that know more about it than me but the C&S cars I remember seeing photos of were truss rod cars.  The FW&D might have just used CB&Q cars, I don't know if any were actually lettered FW&D.

Last edited by oscaletrains

Dear Mr. Lee,

the C&S had no such cars, the FW&D did "have" some SM-18's (very similar but built for larger weights and slightly different bolster position and wheelbase span. The Rails Unlimited kits can be made into SM-18's, all parts provided. Here's what the 1966 ORER says, very exact information:

SM. 36' Stock Car. Steel Underframe. Class SM-18. Built 1927 at CB&Q Galesburg. Series #56700-56924. 200 cars leased to FW&DC in 1943 (series #56700-57447) and renumbered FW&DC Series #3001-3200.

SM. 36' Stock Car. Steel Underframe. Class SM-18. Built 1926 at CB&Q Aurora. Series #56925-56949. 200 cars leased to FW&DC in 1943 (series #56700-57447) and renumbered FW&DC Series #3001-3200.

SM. 36' Stock Car. Steel Underframe. Class SM-18. Built 1927 at CB&Q Galesburg. Series #56700-56924. 200 cars leased to FW&DC in 1943 (series #56700-57447) and renumbered FW&DC Series #3001-3200.

I am not sure about the correct lettering of the leased cars, some leased locomotives even haven't changed their lettering for a long time. I would suggest that in 1943 nobody down in Texas would have repainted 200 stock cars but that could have been done at a later stage. Don't know. 

 

And here is some info that I was able to gather through the BRHSlist@groups.io e-mail group: 

Mr. Steven Holding, Burlington specialist and former stock yard employee wrote:

Use the Rails Unlimited Kit and paint it CB&Q as they were free running and could be found every where on the system both FWD and C&S.  Cattle would be moved from south to north to follow the grass and then back again in the fall.  Feeders calves would move from the north and south west to the mid-West to feed on the corn fields after picking in the fall
 
Thanks to the vast knowledge of these Gentlemen I can share some of the other aspects of C&S stock cars with you here:
 
 

This a car diagram for the C&S 11000 series stock cars from Burlington Bulletin 25. You can decide if the MDC/Roundhouse version is close enough (edit: could serve as a scratch building referrence). Also none of these cars lasted into the WWII era.

Bill Hirt

And here's an other Info by Mr. Hirt

Looking through Burlington Bulletin #25, the C&S had some very unique stock cars. There were a set built in 1910 numbered #26000-26249 that were built by ACF in Terre Haute IN. They were National Dump Stock Cars with 14 drop doors in the floor so they could be used in multiple services. The text says they lasted through World War II, but were all gone by the early 1950s. This would suggest they kept their original K brakes until retirement. I checked the January 1943 Official Railroad Equipment Register and it shows there were 231 cars listed in the series. The January 1953 ORER lists 2 cars in service.

Bill Hirt

I also did some research about the 26000 class cars but not yet have I revealed too much. I am very sure that a Rock Island car that is featured in the very cool publication of the Rock Island Historical Society on page 16 is a close cousin of our C&S car. Have a look.

rockislandreporter.com issue 11

Believe me or not, I have fun in having nearly correct rolling stock and building a time machine that brings you back in time.

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Here are some impressions of a little progress of the project. Usually I have one or two hours in the morning in the workshop and it really makes me happy for the day.

 

The first of the two ready for primer with all Z-braces and underbody detail in place

 

All steps in place

 

I made the stirrups by flattening the ends of round wire on the anvil with a flat punch, I taped the bent steps in place first to save time on the floor searching. Tichy Train Group rivet heads were used on the stirrups.

The second car received its Tsunami sound car decoder, I still wait for the current keeper to arrive, which I think is essential to have. 

I used a ESU 40mm round speaker with enclosure (50323) and hot glued it to one car end before the roof was installed. I tested many speakers and found that you can't predict sound from measurements alone. 

An easy way to make power trucks – I converted Jay Criswell's brass andrews and they work great. My Atlas test track frogs are insulated, beside that the car works fine even without current keeper. I really love the sound car – it really brings your train to life!

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Update for the SM-16 stock car. I'm sure many of you feel the same here - sometimes you just can't work on your project till the end without a little pause. I took that pause to think about the car's final appearance and decided to try a fading approach.

Since I model 1946 I wanted this car to reflect it's original paint and black herald with just the data lettering updated. Also the brass trucks have been updated to p:48 by now, I still experiment with some chalks but I'm close. Brake wheel and roofwalk support irons are still missing.

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