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Old 01-26-2011, 06:29 PM
Carl@Semroc's Avatar
Carl@Semroc Carl@Semroc is offline
Junior ??? Rocketeer
Join Date: Mar 2005
Location: Knightdale, NC
Posts: 1,470

It is usable now. I need a help document!

Start with "NEW" to create a basic ogive shape. Adjust the shoulder to match tube or adjust the length of the first section to change size, then hit "REFRESH". When you are satisfied with the design, give it a name and hit "SAVE" to save it in your directory. Each SAM user can only save to his own directory and not to the Semroc main directory.

Another way to start is select a well known nose cone, transition, etc. in the Catalog Number field and clear the Owner field. This will bring up the current Semroc specifications for a part. You can modify those parameters and save it in your directory as a new part.

If you want to share your design with other SAM's, leave the Public field as "Yes". If you set it no "No", it is your private design and only you and Semroc can access it. Each balsa part is accessed by its unique Catalog Number and Owner. There can be as many BNC-20N nose cones as there are SAM's and they can all be different shapes! If you want to load a fellow SAM's design (if it is Public), you must enter the corresponding SAM# in the Owner field.

Use the "Notes" field for information such as "Upscale of Centuri BC-71" or "First test of my new nose cone", etc. This will show up in the master list of all nose cone (N.B.,add later.)

Most common types are Ogive, Ellipse, and Cone. They all need a beginning diameter, ending diameter, and length. The Control X1 is to modify the "fatness" of the shape. It can range from -1 (thin) to 0 (normal) to +1(fat). Many of the old Estes nose cones seemed to be around .2 for their ogives.

Bezier is a hard one to describe. Look up bezier curves for much more detail than I understand. It allows you to determine the shape of a curve by defining a starting point (begin diameter), ending point (end diameter) and two control points. The two contol points each are defined by x and y coordinates. If you have a shape in Corel Draw (or equiv.) you can read the bezier coordinates and enter them directly. (N.B.,Drawing needed!)

The Power, Haack, Parabolic series are identical to the ones in RockSim. Until now, I have not seen many of these three actually used in production nose cones.

The Split section is used to provide a saw point to separate two parts. See the BNC-3ET for an example.

The Flat is used to terminate a coupler or transition.

The None ends the nose cone. If you want to add an additional section, change the final None to the next shaper. See the TA-2050 for an example. See the BNC-2 for another very complex design.

Every balsa part generated can not be made on our equipment. The tool gets in the way if there is too much "flare" in the shape. (N.B.,Need test for tool hit.)

When you hit "Save" or "Save As", the program calculates and writes your unique cnc file to our server, so we can cut your balsa part minutes later. It calculates how long it will take to cut the part, how much balsa is needed, and calculates the volume of the part, its weight (based on 7lb/cf balsa), its length (minus shoulder) and its retail price. It also sends us an email to tell us that it has been written. (N.B., add capability to check box to designate whether this is for a future design or current need.)

It is possible to upscale and downscale a current design by scaling all the numbers provided with a calculator. Later, I will add a scale button to simplify that. For example, reading the beginning shape, then using a pull-down box to select the target tube type, like BT-20 to BT-70. As many times as I have done that, you would think I had already added that.

This is wordy without many pictures, so it will take some playing with it to get proficient. Hopefully, we will have several SAM's that can help with your project.
Carl McLawhorn
NAR#4717 L2
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