Building a peanut scale model

[flailing]

I thought I might show how I go about building a peanut scale model and post pictures as I go along, if you would like to build along with me a free plan can be found at the provided link. The model I have picked for the build along is the Kieth Rider Jackrabbit drawn by Tom Nallen and can be found here. http://mywebpage.netscape.com/dmlivesay/peanutplans.html[/url]
The Jackrabbit is a super flier and will demonstrate most of the building skills needed for most peanut models.

So download and print the plan, read it over and get a feel for how it's built, tonight we start the build, yes I will post pics!:D

[flailing]

We have a one day delay, I have redrawn the formers and ribs in Autocad to fit 3" wide balsa and I will show you how to make your own print wood for the Jackrabbit. I will make the part file available, anyone want to host it online for download? otherwise I will have to e-mail the file.

[JCastle]

As long as the file is less than 100K just attach it to your post as a Zip file. Just like attaching a picture.:)

p.s. Thanks for doing this. I am looking forward to it.



John

[flailing]

Download the .DXF file for the Jackrabbit parts. I have made the file a DXF so that most cad programs can read it. I don't know how accurate the parts will be as they were traced from a scanned image, but I am sure they will be close enough. You may notice I omitted the spar notches in the ribs as they never line up properly, I will explain a much better way to get nice straight notches when we get to that point.

[flailing]

Extract the .ZIP file and open it in your cad program. The file is arranged to fit 8-1/2 x 11 paper. Follow the next steps exactly, print the parts out, feed the paper in the straight through path on your printer. Measure the drawing the border around the parts is 3" x 10" make sure the dimensions match, make any adjustments until they do. Take the printout and attach a 3 x 10 piece of 1/32 balsa using a very very light mist of spray glue right over the print out. A glue stick would also work to attach the balsa you won't need much just enough to hold the balsa in place during the printing. Now feed the balsa / paper sandwich through the printer and watch the printwood come out the other side Ha!
My printer prints just fine on 1/32 balsa but 1/16 is too thick so we will have to laminate 2 pieces of 1/32 together with white glue. The parts are seperated into 1/32 and 1/16 sheets, cut the 1/16 side free, spread some white glue on the back and laminate a second sheet of 1/32 balsa, wrap the lamination in waxed paper and weight it down on a flat surface until dry. The laminated parts seem to be stronger than 1/16 solid parts.

[flailing]

You should get this. Note the ribs on the left are 1/32 everything elese is 1/16.

[flailing]

If you are unable to print the wood parts there are other methods I will explain.
1. Make a copy from a copier or print using a laser printer, a bubble jet printer will not work. Iron the patterns onto the wood. I have not tried this but many tell me it works.

2. Use a light coat of spray glue to attach the patterns to the wood. I have used this method but on thin wood it can be difficult if you get too much glue.

3. Use a straight pin and poke holes about 1/16" apart all around the part outline with a piece of balsa under the paper, When you remove the paper you can connect the dots. Works well but is time consuming.

4. Send the file to a laser cutter.

There may be other methods if you have one I would like to hear it.

[flailing]

We need to make a few little tools to help us, there not hard to make but will help a lot. We need 2 sanding sticks one 1/32 wide and the other 1/16 wide, glue a strip of sandpaper to the edge as shown, the 1/16 wide one you can use balsa but the 1/32 wide you will need basswood or ply. We will use the sanders to make the stringer notches. The glue applicator is a sewing needle stuck into a stick of balsa and half the eye end clipped off to make a fork, I hope it shows up in the pic. we will use it by putting a few drops of C/A on waxed paper and use the fork to pick up a drop of glue, when you touch the joint with the fork the glue will transfer to the wood, this thing works great. Lastly it really helps to have a balsa stripper, the one shown is a Master Airscrew stripper and is the most used tool in my shop.

[flailing]

OK let's start building, you have cut all the parts out right ?
For years we were told to pin the upper and lower longerons in place then fit the uprights, a real pain there's a better way. Cover the plan with waxed paper and pin the 1/16 sq. upper longeron in place, note the pins just off to one side of every upright location. By the way I use a ceiling tile to build on it takes pins eaisly.

[flailing]

I use thumbtacks to pin the strips down, if you use straight pins don't pin through the sticks they will split, instead make an X with the pins as shown.

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Hold a 1/16 sq. stick in place at the wing saddle location #4 and put a drop of glue where it meets the upper longeron with your glue applicator tool. We will start here as we are making a self jigging structure, you will see.

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Trim the 1/16 sq. stick until the wing saddle part fits over the plan correctly, glue the stick to the wing saddle and pin it down.

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Glue the 1/16 sq. uprights to each end of the wing saddle, leave the sticks long and trim them off after gluing, you can see the front one has been trimmed.

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Glue the 2 gussets in place, use the tip of an X-acto knife to hold them in place as you glue them.

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Glue the remaining uprights in place and the 1/16 x 1/32 diagonal braces, again leave the sticks long and trim them off after gluing. Pin the free end of the uprights down as shown. Note you will need to use a 1/16 x 3/16 strip at location #7 for the motor peg.

[flailing]

Now glue the 1/16 sq. lower longerons in place, wet the rear longeron between #6A and 7A with a little Windex or saliva to help it form the slight curve.

[flailing]

Carefully remove the pins. The framework will be stuck to the waxed paper slide a thin metal ruler or something thin between the wax paper and the frame to free it. There you go one fuselage side, now build another just like the first one, if you use the same pin holes the second side will come out the same as the first one, a good thing we want to make them both identical.

[flailing]

I like laminated outlines for the wingtips and tail surfaces there lighter, look better, and are much stronger so that's what I am going to show. If you want to use the sheet parts be my guest the construction will be the same. I have attached another .DXF file for the lamination forms, again the border around the forms is 3" x 10". Print the file and spray glue to a piece of 3/32 balsa or some blue foam, cut the forms out and sand the edges smooth, if you use balsa rub a candle around the edges to keep the laminations from sticking the laminations won't stick to the foam as bad so you can skip the candle. Next cut some 1/32 x 3/16 strips about 12" long, cut a dozen or so you will most likely break a few. Place the strips in a shallow pan and soak them with Windex or any glass cleaner for that matter, the amonia in the cleaner helps make the strips nice and pliable for the next step, let the strips soak for several hours.

[flailing]

While the strips soak here's a link to a site with pictures of a finished Jackrabbit to give you inspration. Looks to be the same plan, and see he used laminated outlines too. http://member.nifty.ne.jp/tetsuro/public/ffmodel/peanut/hangar/hang014.html

[flailing]

Now that the strips are good and floppy tear off about a dozen strips of masking tape and stick them to the edge of your table so they will be handy. Take a strip out of the Windex and swipe it dry with your fingers, run a bead of white glue down the length of the strip and stick another strip too it. Tape one end of the glued strips to a lamination form and start wrapping and taping the strip to the form. The toughest part will be the top of the rudder it has a small radius you have to wrap around, if you pull on the strips as you wrap them it helps a lot. You made extra strips so if you break one start over until you get it right. Now set the laminations aside to dry for at least 24 hours. I like to get this out of the way early so when I need them their ready. Now back to the fuselage.

[flailing]

Now you should have 2 fuselage side frames complete and the laminations set aside drying. Next we are going to join the fuselage sides together over the top view of the plan to form a box. The next steps can go very wrong so work carefully and if something is not right fix it before you glue anything. Make 4 or 5 triangles about 2" per side from foam or balsa, make sure there 90 degrees. Pin the triangles to the top view as shown, 1 at the nose 2 or 3 along the middle and 1 at the tailpost.

[flailing]

Now pin one of the fuselage frames down and tight up aginst the triangles, note we are building the fuselage upside down so the wing saddle should be facing up.

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Cut 2 cross pieces for each upright location, one for the top and one for the bottom.

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Glue one cross piece to the side frame and set the other aside, keep them in order or you will have a heck of a time sorting them out when you need them.

[flailing]

Now glue the other side frame in place, pin it down in a few places as you go along, make sure the cross pieces are pushed down aginst the building board before you glue them.

[flailing]

Now glue in the remaining cross pieces you set aside starting with the ones at the triangle locations, check that the fuselage stays tight to the triangles often as you glue the cross pieces in place. Carefully remove all the pins a pair of tweezers will be of help getting the inner pins out, now you should have a nice straight and square fuselage.

[flailing]

Pin the fuselage to the board as shown and glue former #1 and #1A in place, my formers were wider than the fuselage, not to worry just let them overhang the fuselage by the same amount on each side we will sand them flush later.

[flailing]

Glue the remaining formers in place, check their location aginst the plan before you glue them in place.

[flailing]

You may have noticed your glue applicator tool gets clogged with glue, keep it clean by wiping it with Acetone or fingernail polish remover it works best when it's clean.

[flailing]

Use your 1/16" sanding tool to make a notch in the center of the formers as shown. The formers are fragile so use a light touch and try to support the former with your fingers as you sand. Sight down the length of the stringer so it's nice and straight adjust the notches until it lays in straight, nothing looks worse than crooked stringers. Use fairly stiff straight grained balsa for your stringers so they won't bow when the covering tightens up.

[flailing]

You will need to make a 1/16 x 1/8 tailpost to support the stringers as shown.

[flailing]

On the bottom stringers at the tail you will need to bevel the stringers to a point so they are flush as shown.

[flailing]

Note that only the center stringer is 1/16 square all the remaining stringers are 1/32 x 1/16, use the 1/32 sanding tool to add the rest of the stringers. Work the stringers from side to side, do one on the right side then one on the left, right, left, right, left this way you wont bow the fuselage. Keep the stringers flowing smoothly adjusting the notches as before. Don't worry is the stringers don't match the formers just get the stringers in straight we will fix the formers later. Take your time here it really shows in the finished product.

[flailing]

Here it is with all the stringers in place.

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Note how the top stringers fair into the tailpost.

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Here's how the bottom stringers are tapered.

[steve lewin]

It's gone very quiet. Did you lose interest ? I was hoping you'd get to some covering hints sometime cus I'm rotten at lightweight covering ;).

That plane's a bit too complicated for me but I was trying to follow along while building my boring Peck Lacey M10 :(.

Steve

[flailing]

The intrest is still here, just up to my armpits in projects, I will finish soon maybe this coming weekend.

[Bob Chiang]

Hi Flailing,

I've just re-discovered the free flight section and read through your progress report. Very nice treatise on building.

-Bob Chiang

[mescal1]

just thought i'd put this back at the top. i'd love to see what
else has been done on it, and maybe if it's flown yet!
mike

[Huckebein]

Wow! This is a extremely well done tutorial! I am currently starting a Lee's Hobbies Siemens-Schuckert DIII peanut. This article has totally made me re-think my construction methods. Kudos!!

Huck

[Mike Taylor]

Great tutorial. Keep it up! Let's see some covering!

[Harry Mueller]

Is this thread dead? This would be a perfect project at this time for me and I'd love to start it. Finishing it up though would be useful.

Thanks....Harry

[Arthur_GA]

BUMPing the thread... is it finished yet? :-)

[Snitch7]

I can't believe I've missed this thread until now. Excellent stuff Gumbander.

[Tim Wolff]

Nice job on this tutorial so far. Please pick it back up.

[fixwingagain]

I just found this thread. Nice work. Are there any updates ?

[Bud Morrison]

heh hope this one didnt make it to the the I'll get back to working on it someday box. I have a few of them box's around :)

[chevy43]

Nice old thread!

The glue aplicator and the former notcher are priceless!!! Thump tact to clamp stuff down is a new for me too!

Just those tips alone will help me so much!

[mode1]

Stumbled upon this project, enjoy reading and watching the progress. I had a long career as a youngster building stick and tissue models. Found several good suggestions here.
Almost makes me want to give it another try after a long, long time. The RC stuff is great but the small relative simple models sure have their attraction.

[MrBungle]

So flailer, finished yet?

I've got here a Matt Halton designed Tiger Moth that I started 6 years ago, just finished the top wing and glued another two peices of balsa to the fuz... thats enough for this year!! LOL

I wonder what the world record is for slowest build?

[StCalvin]

Wish I had found this a long time ago

[eliworm]

So flailer, finished yet?




I looked at flailing's profile and he has not been active since Nov 10, 2004. Some of his threads mention a medical problem. Hope everything worked out.

Jim

[MrBungle]

Hi Jim, (or is it Holly? :D )

I too hope everything is okay, tho lack of posting doesn't look good :(