I have been out of town for a couple weeks, on vacation. I now have my tubes from Totally Tubular!!
I have been kicking around how to mount the fuel tubes. Attached are some sketches. Putting the tubes on a .935 radius (scale dimension) the largest ID to fit inside the tubes is 1.17" The closest tube I can find is a Quest T30 which is 1.18" OD. I am thinking now of using a BT-50, make it full length and fly on a single 24mm motor.
I am attaching a drawing which has some part dimensions, which is currently, a hybrid of the core using the Quest tube and the BT-50. You will note there is a gap between the engine tubes and the stuffer--the Centuri kit has a cardboard bulkhead there, to adapt the two engine cluster to the stuffer tube.
Using the original Centuri instructions, I find some of the part lengths aren't to scale--or since I can't find the templates mentioned in the instructions, I may have incorrectly interpreted some of the part placement. I decided to make all the lengths to scale, so I am moving away from being a Centuri clone.
I still have a question about the aft tube length.
George Gassaway's drawing shows the top to be at STA 192.6. I can't find this documented on the Saturn 1B drawings I have (NARTS packet and
Scott Lowther's APR site). Scaling the pixels on these drawings, I get the top at 193.75. George, is your dimension an actual STA, or did you scale it?