But let's get back to looking at how I approached the Excelsior and how I am sticking to that approach for all the other ships.
What determines scale? Well, there is canon for one. For another it is the details on the model. Excelsior scales to 467 in both cases. The edge of the saucer is the same as the Enterprise refit, just the opposite angle. And on the model wall in TNG, they are all scaled to the CVN-65, the same ship that the TOS Enterprise was scaled to in TMOST. Also, the scale of the TMP refit is not just determined by some random number. The sets and matte paintings and FX shots were carefully constructed. We see the hanger from inside and out. We have docking ports where we can scale the doors (5 of them). Then we have the egress elevator they used to get out on the hull when they reach V'ger. These all scale to the same thing. The only thing we have on Excelsior is a few rows of windows on the secondary hull that feel too close. The deck height would have to be about 7 feet. Not very comfortable, but if we extrapolate the design of the TMP refit, this should be the cargo area. Cargo areas could have warehouse style flooring. We see this in TMP, but the deck spacing is spacious. But perhaps there is a reason for less space in this area of Excelsior. It is hard to put in words what I envision in my head.
When we get into the TNG world, the ship designs that appear have longer vertical windows. This sets the scale for all those designs. Both in terms of the spacing and window size. The Galaxy, Ambassador, and Nebula classes all follow the same window pattern. And the Galaxy, Sovereign, and Intrepid classes were all designed in exacting scale, like the TMP refit. So their sizes are know and certain. While they only built a limited number of sets, the sets they did build fit in the designed exterior. Except the Ent D hanger. Ignore the hanger. The reused ships and side ships were not always as carefully scaled.
The bridge. Here is why what it looks like and its size and placement don't matter. In 1964 Matt Jefferies designed the bridge set very carefully to fit in the upper dome on the saucer. We see (in 1964 quality FX) the bridge in the dome. This stays true for the second pilot. Then they cut the model down (the windows added in lighting process provided the line to cut the entire bridge down) and the only way to fit the bridge in at that point, is to lower it. We see from the 1968 TMOST cross section that is what Jefferies intended. Then on to Phase II and TMP and the dome fits the bridge again. All good through Star Trek IV. Then in Star Trek V they have to build a new bridge set and they don't give quite as much attention to if it will fit. The Star Trek V bridge might just fit. Might. The Star Trek VI bridge will not. So again to put the interior and exterior in agreement, you have to lower the bridge.
So we come to the Excelsior. The original bridge on this model fools people. It looks so short. Well, the platform it sits on is too short for a deck so it is part of the bridge structure. The bridge we see should fit under that dome with the extra space. Plus the top of the next deck is angled which adds a couple more feet. Then Bill George changed it for Star Trek VI, as well as the hanger front. Neither of these changes is in scale with the rest of the ship. For that bridge to fit the set the ship would have to be longer than the Galaxy class. Roddenberry was dead set against that. That also doesn't fit with the design of the saucer edge. So that means that this bridge structure is just the external structure covering the bridge, not the bridge itself. The bridge itself is sunken. And were do we again find that concept? The Galaxy and Nebula classes. Their bridge is sunken as well. So the sunken bridge is a common concept in Starfleet. A concept that disconnects the exterior design of the bridge from the actual bridge underneath.
So when we look at the Centaur or Discovery Enterprise, the models should tell us the scale. They do. The Centaur features many TNG era windows. Examining the ship design in light of those windows and the hanger leads to scale the ship at the scale of the Excelsior parts. The windows are the right size and line up to actual decks in the Excelsior scale. The bridge is just a dome over whatever bridge is inside. The hanger is key. That hanger is barely large enough for standard shuttles at the Excelsior scale. It would be nearly useless at a smaller scale.
The various kitbashes made from various Galaxy era parts are pretty consistent in their scale when you look at the windows. The windows clearly indicate that most of those kitbashes are much smaller ships. Definitely not in scale with the galaxy class even though they are using those parts.
Every ship design has something that will clearly indicate its sale. Sometimes a particular design as multiple items and multiple possible scales. I feel we have to pick on and I lean toward consistency in appearance. I think starfleet tends to modular construction so given hull areas in common, that is the first thing to look at. Then windows, they other features.
What determines scale? Well, there is canon for one. For another it is the details on the model. Excelsior scales to 467 in both cases. The edge of the saucer is the same as the Enterprise refit, just the opposite angle. And on the model wall in TNG, they are all scaled to the CVN-65, the same ship that the TOS Enterprise was scaled to in TMOST. Also, the scale of the TMP refit is not just determined by some random number. The sets and matte paintings and FX shots were carefully constructed. We see the hanger from inside and out. We have docking ports where we can scale the doors (5 of them). Then we have the egress elevator they used to get out on the hull when they reach V'ger. These all scale to the same thing. The only thing we have on Excelsior is a few rows of windows on the secondary hull that feel too close. The deck height would have to be about 7 feet. Not very comfortable, but if we extrapolate the design of the TMP refit, this should be the cargo area. Cargo areas could have warehouse style flooring. We see this in TMP, but the deck spacing is spacious. But perhaps there is a reason for less space in this area of Excelsior. It is hard to put in words what I envision in my head.
When we get into the TNG world, the ship designs that appear have longer vertical windows. This sets the scale for all those designs. Both in terms of the spacing and window size. The Galaxy, Ambassador, and Nebula classes all follow the same window pattern. And the Galaxy, Sovereign, and Intrepid classes were all designed in exacting scale, like the TMP refit. So their sizes are know and certain. While they only built a limited number of sets, the sets they did build fit in the designed exterior. Except the Ent D hanger. Ignore the hanger. The reused ships and side ships were not always as carefully scaled.
The bridge. Here is why what it looks like and its size and placement don't matter. In 1964 Matt Jefferies designed the bridge set very carefully to fit in the upper dome on the saucer. We see (in 1964 quality FX) the bridge in the dome. This stays true for the second pilot. Then they cut the model down (the windows added in lighting process provided the line to cut the entire bridge down) and the only way to fit the bridge in at that point, is to lower it. We see from the 1968 TMOST cross section that is what Jefferies intended. Then on to Phase II and TMP and the dome fits the bridge again. All good through Star Trek IV. Then in Star Trek V they have to build a new bridge set and they don't give quite as much attention to if it will fit. The Star Trek V bridge might just fit. Might. The Star Trek VI bridge will not. So again to put the interior and exterior in agreement, you have to lower the bridge.
So we come to the Excelsior. The original bridge on this model fools people. It looks so short. Well, the platform it sits on is too short for a deck so it is part of the bridge structure. The bridge we see should fit under that dome with the extra space. Plus the top of the next deck is angled which adds a couple more feet. Then Bill George changed it for Star Trek VI, as well as the hanger front. Neither of these changes is in scale with the rest of the ship. For that bridge to fit the set the ship would have to be longer than the Galaxy class. Roddenberry was dead set against that. That also doesn't fit with the design of the saucer edge. So that means that this bridge structure is just the external structure covering the bridge, not the bridge itself. The bridge itself is sunken. And were do we again find that concept? The Galaxy and Nebula classes. Their bridge is sunken as well. So the sunken bridge is a common concept in Starfleet. A concept that disconnects the exterior design of the bridge from the actual bridge underneath.
So when we look at the Centaur or Discovery Enterprise, the models should tell us the scale. They do. The Centaur features many TNG era windows. Examining the ship design in light of those windows and the hanger leads to scale the ship at the scale of the Excelsior parts. The windows are the right size and line up to actual decks in the Excelsior scale. The bridge is just a dome over whatever bridge is inside. The hanger is key. That hanger is barely large enough for standard shuttles at the Excelsior scale. It would be nearly useless at a smaller scale.
The various kitbashes made from various Galaxy era parts are pretty consistent in their scale when you look at the windows. The windows clearly indicate that most of those kitbashes are much smaller ships. Definitely not in scale with the galaxy class even though they are using those parts.
Every ship design has something that will clearly indicate its sale. Sometimes a particular design as multiple items and multiple possible scales. I feel we have to pick on and I lean toward consistency in appearance. I think starfleet tends to modular construction so given hull areas in common, that is the first thing to look at. Then windows, they other features.