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  1. #1
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    Executioner Clone Build

    The Estes Executioner has been discontinued from the 2012 catalog. You can still find these kits in the retail channel, but they will dry up eventually. Thankfully this is an easy kit to clone inexpensively.

    Another good reason for a scratch or clone build is that you can modify anything you want to get the desired end result.

    I have an Executioner clone which is starting to show it's age. It has a few dents in the balsa nose cone, a couple of marks from "almost-zippers", and two of the fins have been re-attached with rather liberal amounts of 5-minute epoxy.

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    Since I already have all the necessary parts and pieces in my "parts bin", the time is ripe for a new clone. Besides, it's Sunday, and It's raining... no other excuses needed.

    Plans for the kit can be found on the JimZ website at
    http://www.spacemodeling.org/JimZ/es...er/est1951.pdf

    The plans are .pdf and include a full size fin template. Which is helpful.

    I use OpenRocket
    http://openrocket.sourceforge.net/

    along with the plans and the rocksim file found at EMMR Rocket Reviews.

    The rocksim file is very close with the fin template. I'll be tweaking the file in OpenRocket to match my build.
    Fin templates print right from OpenRocket after I adjust the fin tabs for my build.

    With my clone I'm planning to modify the original design to include:
    - A zipperless/baffle mid-break design.
    - Launch Lugs and Rail buttons
    - Screw-on motor retention
    - Kevlar shock cord
    - Nylon chute
    - TLAR precision cloning methods as needed.

    *TLAR "That Looks About Right"
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  2. #2
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    I decided to use a 24mm motor tube, rather than upgrade to 29mm. I have a bunch of 24mm motors to use and not enough 24mm rockets. This will be a reasonably light build and flies nice with the 24/40 case and reloads. There is always the Pro24 line from CTI if I feel the need to push it into *LEO.

    Nose cones can be sourced from Semroc, Balsa Machining Service, or this guy on eBay. The eBay one is plastic, and that’s the one I chose to use this time.

    The nose cone gets a quick skim-trim with the hobby knife to remove any excess flashing. A shaving/scraping motion with the hobby knife really makes those mold seams disappear. Then a quick wash and dry to remove any silicone mold release or other contaminants. I use a green (coarse) Scotch Brite pad in the wash to take off the "shine" and prep the plastic to accept paint better.


    *LEO "Low Earth Orbit"
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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  3. #3
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    A few holes are drilled in the side of the nose cone shoulder to aid with a more "mechanical" bond to the airframe since glue won't stick to the plastic very well by itself. All holes were carefully drilled with "tlar" precision measurement.

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    Two holes are drilled in the base for the shock cord. I also scuffed-up the shoulder of the cone with some 80 grit paper for better glue adhesion. It won't show, so it doesn't need to be pretty.

    At this point I measure and weigh the nose cone and adjust the .ork sim file accordingly. Even though tlar will be used in the build, I want the sim to be reasonably accurate.

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    I'm using about 3x the length of the rocket for the shock cord. 9-10 feet or about 3 meters, tlar again. Kevlar can be hard to cut. I use a utility knife with a sharp blade.

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    Tie an overhand loop in one end of the shock cord. This will be the loop that later connects via quick link to the baffle. Measure about 1/3rd (one meter maybe) from the end loop and make another overhand loop in the shock cord. This is the loop for the chute. Now fold up the shock cord into a neat bundle and wrap it with a small rubber band. Toss it on the scale to get the weight for the sim.

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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  4. #4
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    7th April 2012
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    On a recent order I threw an executioner in the mix, I didn't know it was going oop. Glad I did!

    I'm excited to see what you have in store for your clone, hopefully I can shamelessly steal some ideas from you!

  5. #5
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    Every good cloner has to a a good set of tools and reference material. In addition to the Plans at JimZ's, I found this to be an invaluable help.
    The Estes Body Tube List has the two BT80 airframe tubes at 14.2 inches each. Total airframe length 28.4 inches.

    I'm using Hobbylinc SureFire BT-80 tubes that are 15 inches long. I trimmed an inch and a half from one tube to get 28.5 inches total for the two tubes and called it "tlar".

    The Estes Tube Marking Guide set has a little adjustable stop that works like a depth gauge for marking the cut line.

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    To make neat straight cuts, I measure and mark a line where the cut should be, then wrap a couple turns of painters masking tape around the tube at the line. The tape acts like a guide for the knife.

    Green painters tape - not too sticky, no damage to the tube, and cheaper than the name brand blue stuff.
    It also matches the color of the cutting mat (bonus points)

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    Z is for Zirconium.

    Load a NEW blade in the hobby knife and make several 8-12 or more passes around the tube with the point of the knife. Work slowly and use the tape edge as a guide.

    Peel the tape off and "de-burr" the cut edge with a sanding dowel. (Just a piece of scrap dowel with sandpaper CA'd on one end.) The sanding dowel is used to rough up the inside of the tube so the glue will adhere better. Toss the tube on the scale, and adjust the sim weight as needed.

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    Everything used in the build with the exception of glue and paint gets weighed. I like to get the most from the sim in OpenRocket - It is a great tool.

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    I'm trying to think metric when it comes to rocketry. I weigh things in grams, and have OpenRocket set for metric measurments.

    Science is mostly metric, and rocketry is my excuse to think and work in the metric system.
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  6. #6
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    Great thread ...

  7. #7
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    Looking good so far.
    NAR 91107, Level 2

    Paint caused the drought.

  8. #8
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    27th September 2010
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    Looks good Scott, You running out of BT 80's yet?
    Unstable by design
    www.wooshrocketry.org NAR Sec. 558
    WOOSH Rocketry (mostly) on YouTube - http://www.youtube.com/user/guytogo75?feature=mhee

  9. #9
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    Quote Originally Posted by chadrog View Post
    Looks good Scott, You running out of BT 80's yet?
    Ha Ha - If Hobbylinc ever runs out / stops selling BT80 tubes, I'll probably go into withdrawl...

    Untill then it's all good. I can always get more... and more... and more...
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  10. #10
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    Shock cord to the nose first - then upper body tube to the nose cone.

    Now the un-looped end of the shock cord is passed thru the two holes in the base of the nose cone, and the same old overhand loop knot is tied.

    The two hole method for the shock cord is much stronger than attaching to that wimpy molded part.

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    Dry test fit the shorter body tube to the nose cone. The trimmed end goes on the noes cone. Check for any fitting problems and adjust as needed. Mix a small batch of 5-minute epoxy and glue the tube to the cone. Epoxy gets spread on the inside of the tube, then nose is inserted and twisted.

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    A piece of BT50 is used for the motor/stuffer tube. The tube gets trimmed to 13.75 inches with a razor saw. This can be a sloppy cut as long as one end of the tube remains un-cut (square and clean). This is the heavy-wall BT50 from Balsa Maching Service.

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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  11. #11
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    Vent holes for the AltimeterTwo.
    The AltimeterOne does not require a vented body tube. It works just fine when it suddenly "sees" the lower air pressure right after ejection.

    Not so with the AltimeterTwo. It requires continuous venting of the airframe at all times. (per the user guide)

    I drilled the required 3 vent holes after mounting the nose. Would have been easier to drill before gluing the nose cone - but no problem. Holes are "reinforced" with thin CA to stop the fuzzies. The CA wicks into some of the spirals and darkens the tube. This won't be noticeable at all after painting.

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    Onward - to the baffle.

    The baffle is made from a 4" section of coupler and four bulkheads.
    A #8 eye bolt (plain un welded type) is used for the shock cord anchor.
    I get the bulk heads and centering rings from Balsa Machining Service. These are laser cut 1/8" Lite Ply, and require very little sanding to fit. Without the proper tools it's difficult to make your own rings and such so I just leave it to the pro's.

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    Two of the bulkheads are glued together to make a single strong bulk head for the top of the baffle. That's Prang craft glue I'm using.
    All my award winning rockets are held together with Prang.

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    prang
    verb (used with object) British Slang .
    1. To crash (an airplane, for example).
    2. To damage by colliding with (a car, for example).
    3. To bomb from the air.

    There are a lot of opinions on which type of glue is best. When I read the warning label on the back of the bottle, I knew I had some strong stuff. Here is a close- up of the warning label…


    wait for it...




    wait for it...




    wait for it...




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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  12. #12
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    The bulk plates are sized to fit inside the coupler. They form the Baffle. The center bulk plate gets some random smaller holes. The top Double plate gets the Eye bolt and 5 larger neatly spaced holes. This is a "Low Tech" baffle but this design has worked well for me.

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    The center plate installed

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    The top plate installed. The remaining centering ring will become the bottom of the baffle later.

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    The baffel eliminates the need for flame proof wadding or dog barf. I still plan on using a 9x9 nomex chute protector, just to be safe.


    The first ring ( for the base of the baffle) is glued in place at the rough cut end of the motor tube.

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    Last edited by scsager; 18th April 2012 at 02:01 AM.
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  13. #13
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    what about the color?

    I always try to plan ahead… no really.
    Today I was thinking about the rockets name and color scheme, graphics, paint job, etc.
    So I shot some test paint. I faded Rustolium metallic blue into Rusto metallic black just to see what it looks like. These are the same two colors on my old Executioner clone. The picture isn't real accurate - these are really dark colors (indoors). Might look better outside in the sun tomorrow. The little graphic is something I've been kicking around… I might name this rocket "The Reaper". Not really sure about the paint just yet.

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    My 15 year old daughter really wants to paint one of my rockets too. She is a "self-taught" artist. She want to do "a really Crazy paint job, dad". Her Idea of crazy is shooting a rocket with a paint ball gun.

    She really is a talented artist, I have to give her props, she has skilz. Below is a self portrait she drew in her very first high school art class. I just might have to give her full artistic license on one of my builds… not sure if it will be this one ...

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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  14. #14
    excellent thread. i have two executioners still in the package and one almost ready for paint. but now i may need to drill holes in the nosecone for the shock cord. great idea!

  15. #15
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    Quote Originally Posted by 3boydad View Post
    excellent thread. i have two executioners still in the package and one almost ready for paint. but now i may need to drill holes in the nosecone for the shock cord. great idea!
    Agreed !!

    That molded nosecone "eye" might break off if you look at it too hard.
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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  16. #16
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    Back to the build -
    The fin can section of air frame is marked for fin placement using the trusty old Estes Tube Marking Guide.

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    There is a New "Ultimate" Tube marking guide that Estes is selling now. It looks like a glorified door jamb. I like my old version better.

    Here's a video of the "Ultimate" guide in Action.... (scary)


    http://www.youtube.com/watch?v=4qcvscF2_fo


    Drawer frames or door jam molding… Bah! This little Estes tube marking guide set has so many uses!

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    The fin slots are carefully cut with a sharp hobby knife. I used a 6" long section of coupler inside the tube while cutting the slots .

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    With the slots cut out I start dry fitting the motor tube and centering rings. By test fitting everything first you can be sure stuff fits and make sure it's in the right place.

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    The middle centering ring is glued in place after test fitting.

    After more test fitting to make sure everything fits right, I glued the baffel and motor tube into the fin can section.

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    Last edited by scsager; 18th April 2012 at 03:35 AM.
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  17. #17
    Join Date
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    Need to have Tommy Lee Jones sing in this thread . . .
    Fiesta Area Rocket Team - San Diego, CA

    TRA# 01113 L2, NAR # 38484 -DART, NAR Section #317
    GHS 2011 PB-X ROCstock XXXV GHS 2012 PB XI ROCstock XXXVII PBXII SPRINGFEST 2014 ROCstock XXXIX --> LASTER Blaster

  18. #18
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    Scott, you should try some extruded aluminum "angle iron" for slotting your tubes. I have an 18" length of 1/2"x1/2" stock for marking up tubes and cutting fin slots. It's exceptionally good for cutting slots as you won't shave off any of the yellow plastic straight edge.

    Cheap stuff and it can be easily found at Lowe's or Home Depot.
    Kit (AKA Cranky Kong)
    Total Total Impulse as BAR (2010): 8,466.69 Ns (Equivalent to a 65% M motor.)

    On any number of government watch lists...

  19. #19
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    Quote Originally Posted by scsager View Post
    The bulk plates are sized to fit inside the coupler. They form the Baffle. The center bulk plate gets some random smaller holes. The top Double plate gets the Eye bolt and 5 larger neatly spaced holes. This is a "Low Tech" baffle but this design has worked well for me.
    I'm a little confused by your baffle design. If one of the random holes happens to line up with one of the spaced holes, it would seem to me to be able to pass hot particles which can damage your chute and recovery harness. As far as I know, for a baffle to be effective, there can't be a straight through path. It's designed to block the hot particles, but pass the gasses. There is some good information here:

    http://www.apogeerockets.com/educati...sletter129.pdf
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    NAR 91107, Level 2

    Paint caused the drought.

  20. #20
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    Quote Originally Posted by KenRico View Post
    Need to have Tommy Lee Jones sing in this thread . . .
    All right, who let the secret out? Dude - can you read my mind?

    I have a MIB video link all planed out for later in this thread.

    Patience grasshopper, your wish may be granted (or at least close to it) in due time.

    Stay tuned
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  21. #21
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    Quote Originally Posted by o1d_dude View Post
    Scott, you should try some extruded aluminum "angle iron" for slotting your tubes. I have an 18" length of 1/2"x1/2" stock for marking up tubes and cutting fin slots. It's exceptionally good for cutting slots as you won't shave off any of the yellow plastic straight edge.

    Cheap stuff and it can be easily found at Lowe's or Home Depot.
    Aluminum "angle iron" check, check and double check... 18" or longer for long tubes... good thinking!

    Although "aluminum" and "iron" is kinda like one of those oxymorons. Or as my old High School English teacher used to say -

    "That's pretty ugly language you're using there."

    Get it … pretty - ugly…

    - O.K. , I'm done now.
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  22. #22
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    Quote Originally Posted by qquake2k View Post
    I'm a little confused by your baffle design. If one of the random holes happens to line up with one of the spaced holes, it would seem to me to be able to pass hot particles which can damage your chute and recovery harness. As far as I know, for a baffle to be effective, there can't be a straight through path. It's designed to block the hot particles, but pass the gasses. There is some good information here:

    http://www.apogeerockets.com/educati...sletter129.pdf
    Qquake2k - hope my post wasn't too "baffling".

    Great link to the Apogee News letter - thanks, that ones going right into my library!

    You are absolutely right, my baffle will let some hot particles thru. I'm O.K. with that because I also use a Nomex blanket. My purpose is to reduce wear and tear on the Nomex and still keep the build simple.

    I failed to mention that the random small holes really weren't completely random. The after traveling up the motor tube, the hot particles will be hitting the center (mostly) of the first plate. I avoided putting the "random" holes in the center for that purpose. Still, I have no doubt , some particles will make it all the way through the baffle.

    Hummm… this gives me an Idea for a "seat of the pants" experiment … to try and see just how effective a baffle like this is.
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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  23. #23
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    Quote Originally Posted by scsager View Post
    Qquake2k - hope my post wasn't too "baffling".


    Quote Originally Posted by scsager View Post
    Hummm… this gives me an Idea for a "seat of the pants" experiment … to try and see just how effective a baffle like this is.
    Now that would be an interesting experiment.
    NAR 91107, Level 2

    Paint caused the drought.

  24. #24
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    To the Bat cave!... err umm, back to the build.

    Now the fins can be cut out. I'm using 1/8" Lite Ply that I got from Balsa Machining Service. This is much stronger than balsa and very light. I printed the fin template from OpenRocket, and glued that to a piece of poster board (card stock) - Then I drew out the fin pattern on the wood.

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    Because this is only 3-ply lite plywood it is more flexible in one direction than the other . Fins are arranged/cut to minimize flexibility.

    I have a very limited space to work in. No room for anything - let alone power tools. I wish I had a magic band saw. One that would appear when I need to cut fins, and then magically disappear when finished. One that makes no sawdust and needs no cleanup. Yeah, that's just what I need, a magic band saw...

    Not having that, I use a cutting mat, a utility knife, a razor saw, and lots and lots of elbow grease.

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    I like to listen to "classic" music when I'm building. Pink Floyd, The Who, The Moody Blues, that's the kind of "classic" I'm talkin' about. It seems to help while I'm cutting, cutting, cutting, the fins out. These three took me exactly 42 minutes and 59 seconds to cut out.

    ...and everything under the sun is in tune, but the sun is eclipsed by the moooooooon. The end of Pink Floyd's Dark Side of the Moon, and fin's are done.

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    I sand the fins to get them smooth and round. I'm not trying for an airfoil, or any kind of symmetrical perfection. I just want them rounded and smooth. I think they turned out pretty nice.

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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  25. #25
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    while not messless, a coping saw with a 32 tpi blade does do a fair job of cutting 1/8" ply, he trick is to not force it and replace the blade about every 3-4 fins .
    rex

  26. #26
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    Quote Originally Posted by Rex R View Post
    while not messless, a coping saw with a 32 tpi blade does do a fair job of cutting 1/8" ply, he trick is to not force it and replace the blade about every 3-4 fins .
    rex
    Coping saw - I think I have one of those in the tool box! Have to give that a go on the next build.
    Thanks for the tip!
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  27. #27
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    It's almost FIN-ished

    I use 150 grit to sand the shine off the motor tube and the air frame where the fins attach.

    Sanding enough to get the shine off the tube without going too far and gouging up the surface. This will help the glue get a better grip on the material.

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    Dry fit.
    I always test fit the parts in place before I glue them . This way you can make any final adjustments so everything fits well. The fin below is almost right. Just a little more, sanded off the root edge will be perfect.

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    Double glue joints, I'm really sold on double glue joints.

    #7 on page 5 of the Model Rocketry Technical manual.


    Also discussed at length in the TRF forums Like this example.


    For you G. Harry Stine fans, that's page 44, 7th edition


    Double glue joints are da bomb, the real deal, they work good.

    I use my Estes tube marking guide with some green masking tape to hold the fin in place and keep it straight. There are other methods that can hold all three fins in alignment at the same time . This is the way I like to do it. It's a "one fin at a time" deal - but it gets the job done.

    That Estes Tube Marking Guide ** again - It's the "Swiss Army Knife" of rocket building !

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    ** Also see Stine, 7th ed. pg. 39, Kuhn Fin Jig, fig. 3-13
    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

  28. #28
    Join Date
    18th January 2009
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    Behind enemy lines in Socialist California
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    As to preparing the surface to be glued, I go so far as cutting through the glassine and peeling it up to expose the kraft paper underneath. Most everything requires or gets fillets anyway so there's no visible evidence of my pre-glue surgery when all is said and done. This is particularly true where epoxy is concerned.

    When I build rockets that have actual fins instead of tubes, I do as you do with the Estes marking guide, the only difference being my masking tape is blue.

    I think you could probably get away with cutting fins with a hand-held jig saw. Just be sure to clamp the workpiece down before you start cutting. Sand paper will take care of any irregularities. Man, I do love me some stationary belt/disk sanding machine. Seeing qquake's work with the bandsaw has me pining for one of my own.
    Kit (AKA Cranky Kong)
    Total Total Impulse as BAR (2010): 8,466.69 Ns (Equivalent to a 65% M motor.)

    On any number of government watch lists...

  29. #29
    Join Date
    26th January 2010
    Location
    Northern California
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    10,625
    Quote Originally Posted by o1d_dude View Post
    As to preparing the surface to be glued, I go so far as cutting through the glassine and peeling it up to expose the kraft paper underneath. Most everything requires or gets fillets anyway so there's no visible evidence of my pre-glue surgery when all is said and done. This is particularly true where epoxy is concerned.

    When I build rockets that have actual fins instead of tubes, I do as you do with the Estes marking guide, the only difference being my masking tape is blue.

    I think you could probably get away with cutting fins with a hand-held jig saw. Just be sure to clamp the workpiece down before you start cutting. Sand paper will take care of any irregularities. Man, I do love me some stationary belt/disk sanding machine. Seeing qquake's work with the bandsaw has me pining for one of my own.
    I'd be afraid taking too much paper off would weaken the surface. I haven't had any problems with just sanding the surface before gluing. If I was going to hand cut fins from plywood, I think I'd clamp the blanks together and cut them all at once. I'd use a hacksaw instead of a coping saw. The blade on a coping saw is so narrow, I'd be afraid it wouldn't cut as straight.

    The only reason I have a bandsaw, is because I can't afford a laser cutter.
    NAR 91107, Level 2

    Paint caused the drought.

  30. #30
    Join Date
    24th April 2010
    Location
    Wisconsin
    Posts
    1,021
    Quote Originally Posted by qquake2k View Post

    The only reason I have a bandsaw, is because I can't afford a laser cutter.
    Mmmmmmm……. Laser Cutter…… grrglgrrrrgllgrrgll
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    -Scott
    NAR 91621 L2
    Woosh #558
    KC9WQK

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