RockSim question

Hi All
How do I go from a bt60 to three bt20's to a bt60? The three bt20's will be
a cluster mount and the aft bt60 will have TTW fin attachment. The bt20's
are the problem, I can't get three tubes to show up in the drawing.
John Hornsby
Reply to
a.hornsbyiii
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I'm not sure I fully understand what you are trying to do, but I am sending you a sample file I just did real quick in Rocksim 7. I think what you are missing is the fact that you need to specify the radial position of the BT 20 tubes. Other than that, according to my drawing, three BT20's don't fit in a BT60. I don't think I have any BT60 to try it physically.
-- Eric Benner TRA # 8975 L2 NAR # 79398
Reply to
Eric Benner
According to old Estes cluster kits ("Astron Ranger"?), I seem to recall that they did just that!
-dave w
Reply to
David Weinshenker
Wierd......
When I re-opened the file, the drawing showed them fitting all nice and snug. But when I first drew it, the drawing showed them sticking out the sides of the BT60. I made no changes to the body tubes or their radial positions. All I did was close the program and then re-open it after reading your reply. I guess it pays to refresh the page once in a while during the design process.
-- Eric Benner TRA # 8975 L2 NAR # 79398
Reply to
Eric Benner
I think you're right with the radial displacement. 3 BT-20's do cluster nicely inside a BT-60 in a triangle cluster; its so good its a self-centering fit.
Reply to
Gary
Thanks Eric for the help. The file won't seem to open, but the explanation is what I needed.
Actually thanks to all for the help.
John Hornsby
Reply to
a.hornsbyiii
You can use the Cluster Wizard to create the three MMT tubes. Just put one in first (along with any engine blocks/retainer hooks etc.) and then select the mmt and click on the cluster Wizard button on the design screen.
Reply to
Norm Dziedzic
I found that little goodie *after* I went through the hassle to do it on my own. Ya, thanks Eric! :) I got it done and am gonna have to build it soon, Like this weekend.
Thanks again to all that posted a response.
John Hornsby
Reply to
a.hornsbyiii
Absolutely, triple BT-20 motor tubes do nest *really* nice in a BT-60. There's really no need for a centering ring either. Just plug the gaps with something. I just completed a model a couple of months ago with a 3X18MM cluster in a BT-60. Motor retention is via a central stud and nut. I did make a 3-piece centering ring for the rear to give it a nice appearance and to plug up the gaps.
I didn't bother with any type of centering ring on the front, other than a wrap of masking tape to tighten the fit a bit. I also did TTW fins on it. It files great! There's just something you gotta love about a BT that is crammed full or motors!
-- Joe Michel NAR 82797 L1
Reply to
J.A. Michel

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