16x6.5 garage layout

Need to really think about all those curves on the purple and lt blue runs. Trains going through them will tend to pull cars in the opposite direction the rest of the train will be going and that leads to cars being pulled off the track, etc. The curves look nice on paper and work okay for large layouts, but 16" is not enough space. Of course, you can make them work by running shorter trains at slower speeds, but I'd suggest setting up a test section of track before going too far with that part of the design.

Good point Dave. Right now I rarely run more than 4-5 cars in a train since my current layout is so small though many of those cars are heavy operating cars. I did some additional tweaking when I realized I could use a Ross crossover instead of 4 separate turnouts to connect the loops. That reduced the radius of some of the double curves on the inner two loops. Also thought about dropping the inner loop entirely which would leave room for a yard as well as room for additional operating accessories. I might make an indent in the middle to give the table something of a shallow U shape which would give me more reach room for accessories and give the loops more of slight double dog bone shape. I just finished an N scale layout and am being somewhat unpleasantly reminded of just how huge O scale is when it comes to planning a layout. Jealous of all the guys who have a full basement or room to build out!

That's a right small garage.

Normal size garage for a 1960 Seattle house but it has to share room with 14' paddleboards, bicycles and still leave me room to work on projects so I want to keep it to no more than 6.5' wide. I also want to leave room along the opposite wall for a N scale layout. The kids like running the O scale trains thanks to the operating accessories and sound effects but for pure train running fun I prefer N scale. Everything is 1/3 the price and about 1/5 the space. I can buy three Kato EMD SD70 locomotives for the price of a single MTH SD70! Also looks more realistic since the smaller track allows for more gradual radius curves and there's no 3rd rail going down the middle of the track. It's good to have different scales to chose from. Well maybe not on the pocketbook...

OK, decided to dump the smallest inner loop. Also reduced the S curves. The inward bump on the blue loop gives me room to add additional operating accessories in the future. Also helps to avoid the look of nested, perfectly symmetrical loops which I can't stand for some reason. I thought about using the Ross crossover switch but then I saw the price and decided to go with 4 Atlas switches instead. A little more complicated and not as elegant but it is ~$100 less expensive.