This car has a frame scratchbuilt from evergreen strip and trucks from a Chivers On30 kit. The deck is balsa wood stained with heavily thinned enamels. I had previosuly beleived that balsa would not stain well and that it was better to use basswood, however having seen examples on the web I decided to try it and found that it will stain perfectly well and it does of course have the advantage of being more widely and cheaply available.
The couplers are Kadee #5 which are bolted to the end sills using 10BA bolts into holes which I drilled and tapped.

This car is also scratchbuilt. The body is build from Evergreen scribed siding, however I laminated this with plain plasticard to ensure that the body would have sufficient strength when complete. Trucks are reqular HO items, and the couplers are Kadee #5s bolted to end sills which I added to the chassis for this purpose even though they are not visible behind the side planking.
The car can be operated as it had a complete chassis and couplers, but it currently needs a roof, doors and other detailing including ladder, brake wheel etc.
When I do add the roof I will be sure to drill some holes in the floor first - building a sealed box from styrene using solvent is not a good idea as the fumes are trapped inside and can over time attack and soften the whole car body.

This car is a conversion of an HO heavy duty flatcar which was surplus to requirements. The original car ran on 16 wheels, using double trucks at each end. I had no need for the double trucks, but the fact that the car was heavy duty meant that the side frames were heavier built which makes them more suitable for moving up a scale.
For this conversion I used only the side frames, setting them wider than they were on the original HO car, and one of the trucks for each end. The deck, which I have only just started, is stained balsa as for the scratchbuilt flatcar above.

When complete this car will be a steel bodied gondola. It is based on a Bachmann HO body on a scratchbuilt chassis. The original body was too low to just use as is in the larger scale, so I constructed a chassis from Plastruct I beams to both give it a heavier look and also raise the height. I plan to add corregated ends to match the style of the body.
Due to the construction I used this car will probably be modelled permanently load. If I had removed all the old floor then I could have added a lower wooden floor, but as it is if I did so now the floor would be too high.

I also have a HO tank car body which I plan to mount on either a wood flatcar or a steel framed chassis, and I am testing a contsruction technique to build a round tub which could be used to construct a pickle car.