From memory, I think the big visual differences between the K1sa and sd are the sand domes (sa has split domes from the mallets,) and the sds had boxbox center drivers. I'm sure someone else will further clarify or correct me.

Well the N scale model will be using the shell as a basis, these measurements are strictly to get the closest chassis as we can. We only have two options unfortunately. The shell will be completely rebuilt from a donor.

Concor 2-10-2 compared to a K1

Smokebox front diameter -93.6” actual – 95.6”
Mid boiler over 3rd driver – 102.4” actual – 99.9”
End boiler under 5th driver - 109.3” actual – 102”
Smokebox length -100.8” actual – 86”
Driver diameter 61.6” actual -61.5”
Length from cab to front dropstep - 58.6’ actual – 56’
Cylinder centerline to back of mechanism 49.3’ actual- 47.5’
2ft = .15”
Actual dimensions are from Ed’s book and I measured the concor model using some vernier calipers and doing the math

Looks like the boiler girth is pretty much on the money, alittle on the big side though but I'm not crying about being a few scale inches off. Smokebox is way off...drivers are dead-on pretty rare for nscale.

The extra 2 scale feet is from the added flywheel, in concors brilliance they decided to length the entire shell instead of get a shorter motor or move it forward to accomadate a flywheel in the prototypical space. haha

why on earth did i sell mine...ugh!

I just picked up a kato gs-4 and so far so good. The drivers are beautiful in person and come in at 76" scale with the giant rims we have to deal with in n, without the rims the driver center diameter is 70" but I think its close enough and I'm happy with the diameter.

Boiler is hopeless, I think I'm going to scratch build from styrene tube stock.

Also the cylinders are hidden under the sheathing and are whole and not molded to the sheathing!What a relief!

Regrettably, the tender base needs to be lengthened and trucks separated because it comes in at 24' from center truck wheel to next while the actual spacing should be 29' quite a bit longer for the T1!

yeah unfortunately the K1 and T1 tenders will need to be scratched. if you use thin styrene you may be able to make cross beams to match the curve easy, but it would be fragile and might not hold over time. possible to look into brass sides and a dremel tool...