Estes Saros question...

[Mugs914]

I just ordered a balsa nose cone and transition from Semroc so I can reproduce an Estes Saros (one of my all-time favorites). I haven't had a Saros in decades and while I'm sure I can make a pretty good guess at fin sizes and the length of the rear "nozzle" transitions, I thought I would see if anyone had a Saros and would be willing to take a few measurements for me?

I'm looking for fin sizes (span, root chord, tip chord), tube lengths and the dimensions of the nozzle bit.

The plan is to start by doing an original sized Saros and then go upscale to mid power and maybe high power. Any help would be greatly appreciated!

Thanks!

Mike

 

[mikec]

I ended up pulling the dimensions off the images in https://plans.rocketshoppe.com/estes/estK-54/estK-54.htm for a clone using Semroc parts.

Be warned that the Saros in my experience is not terribly stable. Pretty, though!

 

[Micromeister]

A couple years ago I Downscaled the Saros to T3 body size. As the pervious poster mentioned I had to add a good bit of nose weight to get the model to fly well.

 

[Mugs914]

Thanks Mike, that will work great. I wouldn't have thought to look for the plans. I'd forgotten how detailed they used to be!

Now that you guys mention it I do remember stuffing some clay or something in the nose to aid stability.

I'll probably do a build log once things get moving along...

Thanks again!

Mike

 

[samb]

Don't know if you saw the gallery entry for this one here: https://www.rocketryforum.com/showthread.php?21327-Estes-(Astron)-Saros-(K-54-or-1254)-Gallery

Transitions are cool !

On a side note, I hope all is well with our friend John Lee, the Godfather of the TRF Gallery. The ability to bring order to chaos is a gift !

 

[Mugs914]

Just for reference, I simmed my version of Saros. It looks like .175 of an ounce just under the nose cone you end up with 2.05 caliber stability margin with a C6-5.

Probably cheap insurance... Here's the Open Rocket file:

View attachment Saros clone.ork

(Sorry, that is Open Rocket, not Rocsim as I originally said.)

Mike

 

[Leo]

I am looking for precise exterior dimensions of the fin can from the Saros/Nomad kit.

I'd like to clone the kit as true to the original as possible.

 

[dpower]

Subscribed!

 

[Mugs914]

Got the parts from Semroc and have made a little progress with the build. Got the nose and transition sealed with thin CA and sanded, and the tubes have been cut to length. I've got the motor mount glued up and fin patterns made.

Going to work on the fins tonight. I decided to make the fins from three layers of 1/64" ply laminated together with balsa bevels on the leading edge and throught the wall to the motor mount. They should do a pretty good job of mimicking the fins on the original plastic fin can.

Pics as progress warrants, but here's the stack so far (Sorry for the rotten cell phone pic):

 

[Mugs914]

Got the fins done last night, also got the motor mount glued in and the fin slots cut.

Here is how the fins were made:



And the first dry run:



Still need to do the nozzle transitions, but it is starting to look like a Saros!