RockSim help, again, please

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mikemech

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RockSim help, please
1. I am designing a rocket that requires a paper transition from a BT5 to a BT20. I entered the dimensions, plus .006" on the smaller diameter, set shoulders to 0.00, shape to conical, material to paper, construction to hollow and wall thickness to 0.05. Went to the 'Database' tab, entered manufacturer as 'custom' and part description as 'transition 5-20', click Mark as custom, click Save to database, check data at the bottom of the Database screen, click save, click Choose from database. Yea, it's there!
Now I understand how to do this, right? Hollow laugh.
I will now set up a bunch or transitions of various diameters and lengths. This one will be 'transition 5-50'. Click Mark as custom, click Save to database, check data on Database screen, click save, get error message asking if I want to replace existing file 'transition 5-50' with new information. There IS NO file 'transition 5-50'. What the hell, click yes. 5-50 is now in the database, but 5-20 is gone! Help was no help. I tried opening a new design, just two tubes and a transition, same problem. Watched Tim's video again. Obviously I'm missing something. What am I doing wrong?

2. I have yet to find a program that will print the .svg files accurately. Ideas?

3. The above rocket is my first competion bird, A PD. If I install the BT5 (mmt) as a body tube I cannot slide it , with centering rings, into the BT20. If I install it as an inside tube, I cannot put fins on it. (In the computer design. On the workbench I CAN put fins on it.)

Thanks,
Mike
 
I had no issues with saving the transition I created by following your steps you outlined. I never selected "Marked as Custom" I went to the "Data Base" tab and filled out some information under Manufacturer and clicked "Save to Data Base"

Another screen will come up that list the data base "Select From Data Base" screen with your part. At the bottom Click "OK" and save the file. You can go back into your design and click on the transition and then go to edit tab and then the data base tab. Click on the Choose from data base tab and it should show the transitions you created saved to the data base list.
 
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1. I am designing a rocket that requires a paper transition from a BT5 to a BT20. I entered the dimensions, plus .006" on the smaller diameter, set shoulders to 0.00, shape to conical, material to paper, construction to hollow and wall thickness to 0.05. Went to the 'Database' tab, entered manufacturer as 'custom' and part description as 'transition 5-20', click Mark as custom, click Save to database, check data at the bottom of the Database screen, click save, click Choose from database. Yea, it's there!
Now I understand how to do this, right? Hollow laugh.
I will now set up a bunch or transitions of various diameters and lengths. This one will be 'transition 5-50'. Click Mark as custom, click Save to database, check data on Database screen, click save, get error message asking if I want to replace existing file 'transition 5-50' with new information. There IS NO file 'transition 5-50'. What the hell, click yes. 5-50 is now in the database, but 5-20 is gone! Help was no help. I tried opening a new design, just two tubes and a transition, same problem. Watched Tim's video again. Obviously I'm missing something. What am I doing wrong?

2. I have yet to find a program that will print the .svg files accurately. Ideas?

3. The above rocket is my first competion bird, A PD. If I install the BT5 (mmt) as a body tube I cannot slide it , with centering rings, into the BT20. If I install it as an inside tube, I cannot put fins on it. (In the computer design. On the workbench I CAN put fins on it.)

Thanks,
Mike

Number one is solved. The database requires a part number.
Still looking for 2 and 3.

Mike
 
Can you make the part of the BT5 that's inside the BT20 an inside tube, and join that to a BT5 body tube at the end of the transition? Something like this (done in OR)?
View attachment 149683
Apologies in advance if I've completely misunderstood what you're trying to do.
 
Draw the transition in 2d
Extend the angled lines to their intersection
Center your compass at the intersection and draw a circle that intersects the endpoints of the shorter line(the diameter of the smaller tube)
From the same center, draw a circle that intersects the endpoints of the longer line(the diameter of the larger tube)
Set your protractor at the center of the circles, with zero on one of your lines
Mark the angle given by 180*{smaller tube dia}/{radius of smaller circle}
Draw a line from the mark back to the center
Cut the included area
Optionally, leave 1/8" to 1/4" on one end for a gluing tab


(somebody check my equation - I'm at work and can't lay one out to test)
 
FYI

1. I had not used a part number. If you use a different part number you can modify the transition
and save it without creating a new design. e.g. BT5 to BT20 1" long = part number 5-20-1. If
you decide to change the length to 1.5", change the length spec and save under part number 5-20
-1.5. You do not have to change the description.

Thanks to all!
Mike
 
FYI

1. I had not used a part number. If you use a different part number you can modify the transition
and save it without creating a new design. e.g. BT5 to BT20 1" long = part number 5-20-1. If
you decide to change the length to 1.5", change the length spec and save under part number 5-20
-1.5. You do not have to change the description.

Thanks to all!
Mike

cool :) Glad it all worked out. Sometimes ROCKSIM can be a bit annoying
 
2. I have yet to find a program that will print the .svg files accurately. Ideas?

Well, duuuh.
I found something else I should have seen earlier. Open a design with a transition, click the printer on the toolbar, on the Print Selections menu check the Templates box, scroll to Transitions and check the box, click OK. Prints perfectly!

Between TRF and Michelle at Apogee, all my problems are solved. At least rocket design problems. At least today.

Mike
 
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