And More Scratch Building Ideas

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accooper

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Do you need launch lugs? 1/8 or 3/16?

If you have a child in Elementary School, go to the cafeteria. The straws that they give the students are plastic, with an inside diameter or 1/8th inch. I still have some from when my son was in grade school. Hey, have your kid grab a few for you.

Now Burger King has 3/16 inch ones, that are used for coffee stirrers. Every time I go in there I grab a few.

Both of them come wrapped in white paper.(see enclosed picture. this is an 1/8 inch dia)

I use Testors glue to glue them to my body tubes and I have never had one come off. Although I guess you could use thick CA, if you wanted to.

Andrew
Dark Lord Of The Scratch Builders

launch lug.jpeg
 
Drinking straws were the original model rocket launch lugs! :D The first batch of Astron Scouts (Estes Industries' very first kit) that were sent out in 1961 had sections from red and white striped drinking straws for launch lugs. If you have an unbuilt Scout kit that includes a section of a straw for the lug, you have a very rare item indeed! Your post demonstrates that good ideas never die. :)

MarkII
 
The cardboard tube that Aerotech igniters come in makes an excellent 1/4" launch lug. It also works well for attaching electronics sleds to 1/4" all thread.
 
My son got some from the cafeteria of the University he is going to. Says they are rocket straws if anyone asks.

Andrew
Dark Lord Of The Scratch Builders
 
I actually cut up a Bic pen to get 1/4" launch lugs for a Bt-60 E9 powered night flier that I built on the field.
 
I never though of such a great use for BIC pens.

Andrew
Dark Lord Of The Scratch Builders
 
Whatdayamean Launch lugs!
Bic Sticks make outstanding ROCKETS! NOT just lugs LOL!!!!! They are the perfect ID for MMX motors. Only part of a bic stick thats metal is the tip ball...replace it with a toothpick and all the other frontend parts can be used as a nosecone. a couple little pieces of the inkfree ink tube make perfect MMX launch lugs;)

As Launch lugs Plastic Straws are the pits. Most have to really be completely rough sanded with 80 to 120grit paper all around and applied with epoxy or the pop right off.

If your gonna try to use soda straws you really want to find the old time waxed paper straws. Party stores and some dollar stores carry them. Just a little rub with some fine sandpaper a few drops of your favorite glue and they are on for good.

MM 258a1-sm_Bic-pen OddRoc_06-15-02.jpg

MM 258a2-sm_to g1_7 Micro Bic Pens group pic_03-14-06.jpg

MM 258Lp23a_Bic Pen Odd-Roc On pad_04-19-08.jpg

MM 258Lp23b_Bic Pen Recovery after 175ft flt_04-19-08.jpg
 
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The pen launch lugs worked great on that rocket, but unfortunately at my last launch, it kicked out its engine mount, and I test flew a successor. I'm actually thinking of making more rockets with pen launch lugs, because I have been seeing wear and tear on the normal paper ones (1/4") on some of my rockets.
 
The plastic ink tubes from Bic pens make pretty good Micromaxx launch lugs. Whenever I build a new Bic rocket, I pull the tube out of the pen nib (give it a tug and it comes right out) and then stand it up in a small can (soup or coffee can) that is filled with an inch or two of a citrus-based spray cleaner (almost any kind will do) and leave it in there for a day or two. Capillary action draws the citrus cleaner up into the tube, where it breaks down the remaining ball point ink. The ink then drains out of the lower end of the tube. I don't have to even lift a finger to clean it. After all of the ink drains out, I just remove the tube and rinse it out under the tap and then shake it dry. It comes out perfectly clean. I can then just cut pieces from the tube as needed for use as lugs. The tubes bond just fine to airframes with medium cure or maxi cure/slow cure CA.

MarkII
 
BIC pens also make cool laser cannons for sci-fi themed rockets... I hacked a couple of BIC pens and the cockpit section of an old Apache helicopter model to scratchbuild a static model of the Scorpion fighter from the Buck Rogers in the 25th Century tv show...

Combine BIC pens with 7 toothpicks and a little elbow grease and you can make some neat Gatling Guns for your sci-fi birds as well...

I'll have to go see if I can find the model in the attic at my brother's house and post some pics...

Here's a pic of the prototype though... https://www.universalhartland.com/code/buck101s.shtml

Later! OL JR :)
 
I like to use the dirders from masking paper rolls to join BT-50 tubes. These have an ID of one inch so they are ideal for joining boosters or reinforcing motor tubes. I also use plastic straws for LLs but I use ones that will fit inside each other for extra strength. I make my own baffles from 1/8 plywood and most of my couplers from body tubes. Thrust rings come from spent motors of course. Thin layers of balsa epoxied at cross grains make a tough low/midpower fin. A poor man's fiberglas is Fibatape wall repair tape with multiple coats of wood glue or epoxy brushed on top. With the tape attached from fintip to fintip across the BT the fins are nearly bullet-proof. For transitions I use EMRR's shroud calculator, a large piece of heavy paper, a tack,a mechanical pencil and a length of fine stainless wire. Doubling up the paper with epoxy between and CA soaked on top makes a paper transition as hard as wood and perfect for filling and sanding. These days I find that building a kit is just too easy. Ted
 
When someone starts melting down plastic soda bottles and then extruding their own clear payload sections, let me know... :p

MarkII
 
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