I've finally started on the Semroc SST and I have a question. The Centuri instructions don't give much information on ram-jet placement. They show them at 1.25" apart on center, which doesn't go all the way to the edge of the wing. They also don't show the foward/aft placement of the ramjets. Am I missing something in the instructions, or is this supposed to be one of those TLAR (that looks about right) measurements?

Edit: the instructions show the outboard ram-jet at the edge of the wing. The picture on the front of the kit card shows the ram-jet much farther inboard.

The SST Shuttle has some of the most measurement-less instructions of any Centuri kit. It made me nuts. I set the outer ramjets so the outer edge of the tube was even with the outer edge of the wing; I went for the catalog look. Then I centered the middle ramjet between the inner and outer ones. I also pretty much centered the ramjet tubes on the area of the wing they sit on, front to back. The instructions also don't say how far forward to set the rudder. I set mine 1" from the rear; that's about what it looks like in the catalog shots. You'll find the canards are difficult to line up because there's no line on the main BT to use. I used a 4 fin marking guide and drew lines all the way up. There's more info in my review of the kit on EMRR. Looks awesome when done, though.

Drew

I drew some lines extending from the leading edge of the wings. I'm going to use the TLAR method on the ramjets like you did. I'm also doing things a bit out of order, putting on the ramjets before the rudder so I can lay the thing down on the table while working on the jets. This thing is by far the easiest to build Skill Level 5 kit I've seen so far. Of course we get laser cut fins to make things even better.

The SST was an interesting build. There were lots of TLAR's to the construction. The building is done and it goes into the pile for sealing, sanding and painting this spring. If anyone builds this, I whipped up a convient little jig to insert the inlet cones the proper depth. I just wrapped a used mini motor with tape 1/16" from the end so that the tape stopped the insertion. I cut some of the tape so that the motor could slide up against the wing and body tube. This let me insert them all exactly the same depth and kept them straight. Everything else was pretty much standard construction. Sorry about the pic quality, I used the old camera.

Here's the motor, with plastic cement still on it from use.



SST-1





SST-1 and OT

Nice pair

Drew

Nice pair

I just noticed a hairline crack on the right main wing of my SST Shuttle. I've had that happen several times with large wing area rockets after a few landings. I didn't go nuts with the filling and sanding on this one; it's a real PIA to sand between the ramjets

Looks great, Tim.

Drew