[NRVR-Members] Meeting with NRVR
tweeksjunk2 at theweeks.org
Tue Dec 8 23:50:20 CST 2015
Here are those other button standoff photos:
On Monday 07 December 2015 14:44:55 Thomas (Tweeks) Weeks wrote:
> [CCing the nrvr-members mail list so this will be archived]
> Wow.. if large autonomous roverer/rocket design is going to be at the
> meeting, that would rock! (but also really suck bc I'm going to miss the
> meeting. I'm a huge arduino geek and would LOVE to see an autonomous
> arduino-rover pop out of a big bird! [😊] ) Here's one of my little
> arduino bots I was thinking about popping out of my next big rocket
> (currently seeking a nice big fat rocket for this):
> I'm eager to hear what Bob has to say about 1inch standoffs, but I've done
> some 3/4" standoffs for rail buttons on one of my fat-nose rocket designs.
> It can be done very robustly if you do it right.
> But you're rocket is going to be pretty heavy it sounds.. so before showing
> how it should be done there's a common way you should probably AVOID doing
> it. Below is the common way to make rail-botton standoffs for
> smaller/lighter large nose rockets (which you probably want to avoid):
> It looks nice, but taking that design out to 1" would give you too much
> button torque on a large heavy bird. Plus the screw/epoxy nipple inside
> your BT (body tube) will create a snag point for any recovery gear/chutes.
> But the torque from the 1inch of clearance is the real problem with a
> rocket as heavy as yours.
> Instead, here's a graphical view of how I did it (on this smaller 2.6"
> rocket design) using streamlined basswood blocks and T-nuts creating a
> much wider "hugging footprint" to the standoff (VERY solid):
> The block is sanded to fit the tube by simply putting the sandpaper (rough
> side up) and sanding the button-block directly against the BT.. creating a
> perfect fit to hug your BT and give you a solid anchor.
> This design yields MUCH more lateral rocking resistance (than a simple,
> columnar plastic standoff). If interested, I have some more pics of this
> design at home I can put on my webserver tonight.. I did a longer 3inch
> block standoff like this that will give you room for both outward and
> inward facing T-nuts. Tricky getting it all screwed down without any
> snag-points, but VERY solid, and you end up with nuts and bolts anchoring
> the button base to the BT, (not just some epoxy or a 1inch plastic
> For an even more solid anchor, you could also go with a larger triangular
> block base with three outward facing threads (t-nut style) with
> flush-nut-head inside and screw bolts from the outside with an internal
> re-inforcing ring (fiberglass or aluminum ring) that the internal
> flush-nut mount the block to to give it a super solid mount point. Email
> me off list and I'll get you the other design photos.
> If this is your first HP rocket.. I would recommend comparing deisng notes
> by the experienced experts in the nrvr.org mail list (CCd). If you're not
> a member, students can join for free here http://nrvr.org/membership/.
> However, to beef up on HP rocket design best practices I recommend picking
> up a copy of this excellent HP rocket design book that has decades of
> big-rocket design wisdom: http://www.amazon.com//dp/1412058104
> Any of you other guys have feedback?
> Bob? You done any heavy rocket button standoffs?
> p.s. Fareez.. with a rocket this big/heavy.. you ARE using the larger 1515
> buttons right?
> -8020-style-1515-pair/ (unless Bob recommends something beefier)
> From: Fareez Chowdhury <fareez.chowdhury at gmail.com>
> Sent: Monday, December 7, 2015 1:17 PM
> To: Bob Schoner
> Cc: Kevin Shinpaugh; james desposito; Jim Farley; Jordan Truesdell; Carlos
> Zapata; officers at nrvr.org Officers; Pat Artis; Brad Smith; Eric Plevy;
> Magda Moses; Johnny Jaffee; Ishan Arora Subject: Re: Meeting with NRVR
> Mr. Schoner,
> Any and all advice would be appreciated. I've CC'd the remainder of the
> team so they can be in on this. In case anyone is curious, I am also
> attaching the PDR we've submitted to the competition organizers and for
> which we'll present on Wednesday morning, as well as the OpenRocket file
> we've got going on right now.
> An additional question would probably be: how would you recommend going
> about building a 1" standoff for railbuttons? If you'll see from our
> rocket file (and alluded to in one of the other questions), our rocket has
> two diameters, and the lower stage is of smaller diameter than the upper.
> Since it is not possible to mount the rail buttons on the upper section
> due to payload reasons, we need to build standoffs for our railbuttons so
> the buttons (attached to the smaller diameter tube) can reach past the
> larger diameter upper stage and connect to the rails. What kind of
> shape/material/size would those stand-offs be, etc.?
> On Mon, Dec 7, 2015 at 9:16 AM, Bob Schoner
> <bob.schoner at gmail.com<mailto:bob.schoner at gmail.com>> wrote: Kevin,
> Lets's put this on our calendar and move forward with it. I will update
> the calendar on our webpage.
> We still have interested VT students that we can help out. These are some
> great questions and are always preferred over assumptions when folks are
> getting into high power rocketry. I don't mind addressing one or two of
> these, but would like more people to help out and add their perspective
> I feel like I can offer something on any of these and will volunteer to
> speak on #2.
> Officers and NRVR members, please reply all to:
> - indicate if you can make this meeting for 12/9 at 6:00 p.m.
> - indicate which topic you want to address or research
> We can certainly invite all our members as this may be of interest to them.
> I know December is busy and we are not giving them too much notice. Any
> objections to open this up to the whole NRVR community?
> I'm inviting the L1 and L22 people that I can remember. Think back to some
> of the assumptions you made when you first started and see if you have
> some advice on any of these topics.
> Since Time is short, please reply no later than 11:00 pm of 12/7.
> On Sun, Dec 6, 2015 at 4:03 PM, Kevin Shinpaugh
> <kashin at vbi.vt.edu<mailto:kashin at vbi.vt.edu>> wrote: I think we can get an
> NRVR meeting with you all for after 6pm on Thursday. Space at VT will be a
> good meeting location.
> On Dec 6, 2015, at 3:16 PM, Fareez Chowdhury
> <fareez.chowdhury at gmail.com<mailto:fareez.chowdhury at gmail.com>> wrote:
> Dr. Shinpaugh,
> At the last meeting, you wanted us to remind you to ask NRVR if we can
> schedule a meeting at Space at VT on Thursday (12/10) at 5:00 PM, to discuss
> some rocket concepts and verify some things you guys are doing. We also
> have a preliminary list of questions we wanted to ask:
> 1. Advice for cutting accurate fin slots
> 2. Filleting fins to body tube at root
> 3. How to prevent parachute tangling at apogee (booster main chute and
> capsule drogue chute) 4. Adding a shoulder to a modified LOC PNC 7.51 in
> nosecone to convert it into a 7.51 in to 5.51 in transition piece 5.
> Advice on parachute deployment bag selection for capsule main chute 6.
> Amount of black powder and Pyrodex required for recovery
> Please let us know as soon as possible. Thanks!
> Fareez Chowdhury
> Mechanical Engineering
> Virginia Tech, Class of 2017
> Fareez Chowdhury
> Mechanical Engineering
> Virginia Tech, Class of 2017
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