Making fin guides 'real scale'

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Karl

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I want to print out a fin that will be the excact same size that will be the actual size of the one that will go on the rocket, but what program shoul I use and how would I do it?

My OS is XP, 2nd Edition, but I dont have word, ect. I want to use the fin that I created on Rocksim7 btw.

Thanks
Karl
 

dr wogz

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My choice would be Autocad.

But I am a mechanical designer, and have been using Acad (among others) for well over 15 years. (Pen & paper before that...)

Dosen't Rocsim 'print out' fin templates? I would bet these templates are 1:1.

The other thing, is to pick up a pencil, paper, and a ruler, and draw it out. You drew it in Rocsim, so you should be able to draw it with a pen, paper & ruler.. Unless it's overly complex, you'll only need to deal with 3, 4, or 5 measurements..
 

BHP

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Use print > templates in RockSim. Will give you the fin and tab to the motor mount if applicable. I've used it many times. You can use rubber cement to attach the template to the fin material then easily remove it after you've cut the fin out. It can't get any easier.
 

sandman

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DON'T use AutoCad. Man, that is way more expence than you need.

I use QuickCad made by Autodesk. They make AutoCAD and it is perfect for making professional looking drawings.

The drawings can be printed, converted to many different formats such as DXF and DWG fils that AutoCad can use.

Plus if you look you can find it real cheap, like $30!

Here is one I made and converted to a jpeg.
 

Karl

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Thanks Sandman! Im just searching Ebay for it now :p
I've enquired about getting the parts lasercut so I'll see where that gets me :)

Rather than make a new thread, does anyone know where I can find 2x legnths of 2" tubing that are both over 40" long? And I need a nosecone, and I know where to find one of those ;)
Thanks,
Karl
 

sandman

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Totally Tubular (check with member damage!) Has BT-70 size tube (T-70) at 2.217" O.D.

Or the old Centuri tube size T-2.04" tube.

I think damage has them or can get them.

Unfortunately...they only come 34" long.
 

Karl

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Thanks Sandman. Is balsa suitable for a rocket nosecone that is almost min dia? (38mm)
Thanks
Karl
 

sandman

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Balsa is OK up to about mach 1.5 then it's a crap shoot.

A nice healthy coating of epoxy should solve that problem.
 

ResearchWorm

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Instead of coating with just epoxy, you might want to try throwing a layer of light "finish" fibreglass into the epoxy, just to give it some damage resistance. If you're pushing into regions where Mach numbers are a factor, you also might want to make sure the nose cone's shaped properly so it doesn't cause excess drag.

One thing you might try doing is checking how calibrated the output of your printer is to reality. In your favourite drawing technical drawing program (AutoCAD, AutoSketch, QCad, etc) sketch out a series of squares (full size) at 1 inch, 1.5 inches, and 2 inches. Check the print out with a ruler. There are quite a few printers out there that "squish" geometric figures either horizontally or vertically. However, most laser printers, plotters, and electrostatic plotters are accurate.

Speaking of fin dimensions/profiles, I found a NASA Technical Paper, TP-3615, on aerodynamic control surfaces of historic launchers. I don't remember where I found it, but if you google for 'tp3615.pdf' you should be able to find the URL. Has some really interesting drawings of the Redstone and Pershing controls, and a great scaling shot of for the Saturn V's main engines/fins.

Harm none,

ResearchWorm
 

DynaSoar

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Originally posted by Karl
Rather than make a new thread, does anyone know where I can find 2x legnths of 2" tubing that are both over 40" long? And I need a nosecone, and I know where to find one of those ;)
Giant Leap has 2.152" (54mm) ID non-brittle phenolic tubing 48" long.

From the web catalog:
B-2.152 (54mm) LONG! 48" wall = 0.062" $13.99
 

Karl

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Thanks, I had a go of AutoCad 2005 at my dads work, but it's far to complicated lol. I found the Print > Templates ect on Rocksim but I would like to get the templates out of Rocksim, and put them in a e-mail to my dad at work. Could I export the templates some how?
Thanks
karl
 

DynaSoar

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Originally posted by Karl
Thanks, I had a go of AutoCad 2005 at my dads work, but it's far to complicated lol. I found the Print > Templates ect on Rocksim but I would like to get the templates out of Rocksim, and put them in a e-mail to my dad at work. Could I export the templates some how?
Thanks
karl
When you bring up the print dialog box, check the little box that says "Print to file". Send that file by email (it might need to be zipped, I don't know) and you should be able to send it directly to the printer there.

You might need to select the kind of printer your dad has at work so the file gets formatted for the right kind of printer when creating the file, but probably not. The file should work on most any common printer.
 

powderburner

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Originally posted by ResearchWorm
Speaking of fin dimensions/profiles, I found a NASA Technical Paper, TP-3615, on aerodynamic control surfaces of historic launchers. I don't remember where I found it, but if you google for 'tp3615.pdf' you should be able to find the URL.
RW, would you please post a link to that report? I tried googling that label (and several others) but got no hits. I sure would like to see that report
 

DynaSoar

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Originally posted by powderburner
RW, would you please post a link to that report? I tried googling that label (and several others) but got no hits. I sure would like to see that report
The NASA document server system has it listed as TR-3615 (Technical Report) although right on the front it says Technical Paper (TP).

https://trs.nis.nasa.gov/archive/00000321/

Links to the NASA doc servers as well as gobs of other neat stuff is on the Amateur Rocketry (aRocket) web site at www.arocketry.net
 

ResearchWorm

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I really should have caught the TR/TP difference there. Sorry about that. I've got a 2.6 gig collection of Nasa Docs (mostly Marshall TP/TR/CP and SP-8XXX docs), and a mirror of the index pages for the Marshall server. Next time I refer to a NASA doc, I'll verify what I'm looking at either by going on-line or checking my mirror.

Harm none,

ResearchWorm
 

Stymye

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or go to the arocket website it has links to most of the pertinent reports,,, I found some interesting reports on the buckeling of tubes and nosecone stress..alot of the sifting has been done for you there.

this is just one page from the site
https://www.arocketry.net/sp-8000.html


you can get turbocad for free it will do all you want in a simple cad program and the tutoral is excellent

https://www.freecad.com/
 

ResearchWorm

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Folks, please always take my pointers/bookmarks/suggestions as starting points, not final solutions. It is not possible to find, review, and publish a comprehensive index of resources on all aspects of a topic. My research style is a different from other people's and probably does not mesh with many expectations. I guess this downfall of mine is from being the son of a professional research/reference librarian, as well as being a serious bookworm. I'm not perfect, and I will never claim to be.

Arocketry's got a very good selective topic SP-8K index, and for the missing Suggested Practice documents, a couple SP-80xx's and about 25 SP-81xx's, you have to go to multiple other places. Strangely enough, I was finding electronic copies of SP-8K's, which the TRS main servers said did not exist, on external sites such as Arocketry. Much of the more useful info (aerodynamic profiles for historic vehicles, etc) you won't find in the SP-8K's, as the SP-8K's are "Suggested Practices" documents for space vehicle designers. What you will find in the 8K's though is very useful documentation on design practices, and some historical documentation (Solid Propellant Rocket Nozzles, Explosive Acutators, etc)., and some extraterrestrial stuff (Planetary Atmopheric models, etc). TP/TR/CP's and their like are, for the most part, indexed only on the TRS related servers.

The TP/TR's are the "results" oriented papers, and have experiment, design and mission results. Some of the more interesting stuff I have found in the TP/TR's are the EVA related experiments of the Apollo landings and the SkyLab space metallurgy experiments. Reading a TP/TR with a related SP or CR open in another window is a real eye-opener.

The really current neat stuff isn't always found in the TP/TR's. It can also be found in the CPs (Conference Papers) transcript documents (Metallurgy of Aluminum Lithium alloys, Environmental stuff, etc). This is were you will find odd things, such as ideas concerning prototype propulsion systems (Space Elevators/Tethers), theoretical devices and systems (Anti-Matter Drives, Electromaginetic Confined Plasma Fusion engines, etc) where some of the technology used doesn't even exist outside (or inside) the lab yet.

Harm None,

ResearchWorm
 

Stymye

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Rworm,keep sharing your finds, I've been saving some of the links ,,good stuff
 

ResearchWorm

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Stymye, et al:

I just reread my last post, and I apologize if I came off sounding annoyed. I'd been having a moderately shitty day here at work when I wrote that, and I think I might have let my day here influence my wording here on the forums. I'll try not to let that happen again. So if I ever do sound like I'm stressed or annoyed it's most likely just my job getting to me.

I do have the bad tendency to forget where I have found documents, especially if I've saved a local copy of them. So, I'm going to try doing two things. Index all the stuff I've got (a little daunting), and if I find any more useful stuff I'll try to remember to record where I found it.

On a slightly more interesting topic- Over in the Propulsion forum, I started up a thread hunting for info on the Stanford Wax hybrids (kind of a pet research project of my own). There's a couple of websites mentioned in the thread that are are well worth browsing through. Especially the Hybriddyne forums (www.hybriddyne.com). The Hybriddyne forums are small compared to TRF, but density of info is incredible.

Harm none,

ResearchWorm
 
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