$100 Scratch Build Contest-33" Balsa Bipe

[hillbillynamedpossum]

OK, BEFORE ANYONE SAYS ANYTHING, I AM NOT GONNA BE IN THE CONTEST. WHEN IT COMES TIME TO VOTE, YOU WONT BE ABLE TO VOTE FOR POSSUM.


That being said, Ive wanted to build a midsized balsa and tissue bipe for a while now. So here we go. So far Ive used the following:

from Balsa Wood inc, http://www.balsawoodinc.com/balsawoo...ryproducts_0=3

$ 0.76 for 1 sheet of 1/16 x 3 x 48 @ $0.76 ea
$ 3.80 for 2 sheets of 1/4 x 3 x 48 @1.90 ea
$ 2.40 for 2 sheets of 1/8 x 3 x 48 @ 1.20 ea

$6.96 for Balsa



From my LHS I rounded up:

$ 6.99 for 1 bottle of ca glue @ 6.99 ea
$ 2.16 for 2-56 steel clevis... pkg of 12 for 6.49
$ 2.19 for 2-56 threaded rods....pkg of 6 for 3.29

$11.34 Spent at LHS


From the lumber yard (HERRMANS)

$ 0.48 for quan 3 - 1/8" dia dowell rods at $0.16 ea



From walmart
$0.48 Tissue Paper...50 sheets for $4.00 thats $0.08 ea
4.50 For paint ( 3 bottles @ $1.50 ea)

$4.98 spent at wally world


From Aircraft Spruce: http://www.aircraftspruce.com/catalo...edropclrhi.php

$2.40 for 1/2 pint of dope (1 gallon of taunting nitrate dope for $38.35)


From Hirsch Feed and Farm Supply I got most of the hardware

$10 misc
$5 for acetone

$15 at Hirsch

From West Plains Music Store I got the "e" strings

$2.50 for 2

From Jeff at heads up r/c http://www.headsuprc.com/servlet/StoreFront

$16 Power up 400 sport
$18 Power Up 20 A esc
$3 for a APC prop
$15 for 3) 9 gram servos
$9 for a standard servo..I had it on hand, but thats Jeffs price
$27 for my 2200 mah 3S1P lipo
$13 for a 6 channel Rx......I used a hi tech, but I would have used a Corona If I didnt have it buried in another plane.

$101 spent at Heads up!

Thats about every thing I used. so my Grand Total is:

$144.66!

Glad I didnt enter the contest for REAL...I would have had to cook the books a little!
Possum

[hillbillynamedpossum]

Like I said in the last post, Ive been thinking about this for a good long while. So Yesterday morning I inked out the wing plan and went out to the shop (Stinktier-Fabrik) and did a marathon build. I suffered all day today with a sick headache from the CA fumes, but it was worth it. I keep telling myself that I'm gonna build a down flow vented building/doping table but I just havent gotten around to it yet.

So as the pics show, I got the frame work all done. All I really have left to do befor covering is routing the control cables, and making the hatch.

You might note that on the wing, I run my stringers thru notches in stead of fitting them into slots in the rib. I find it faster to cut out the ribs drill them than try to get a perfect notch. I also think it is a little stronger this way.

The tool in the pics is just a piece of 1/2" key stock. I drilled an 1/8" thru hole and chamfered one side. If you run a piece of 1/8" square stock thru it, you end up with a nice round stringer. I then slip the stringer thru the ribs quickly, because the humidity will make the stringer try to go back to square. A drop of c/a on the rib/stringer joints, and its all over.


Possum

[offtom]

Uh............Possum..............You coulda waited for the rest of us you know.


Your plane looks pretty cool, as usual.

[Stevephoon]

Possum,

This little bipe is looking tremendous. I see tail feathers with your earlier design where the entire elevator and rudder pivot on dowels. It’s really innovative. I can’t wait to see your finished plane.

Steve

[hillbillynamedpossum]

Hey guys, what can I say. When Im up-Im up!

Yeah Steve, the tailfeathers are like I made on the big bird prototype. I find you get a LOT of control from full flying tailfeathers.

Now if I could just fing a center of gravity calculator for a biplane!

Possum

[jungmann1]

Sooooo, you are saying you suffer from bi-polar disorder and timed the build for an "up" period? Sorry to hear about your malady and congratulations on a very cool build! Man, you really knocked that out! Looking like you might have a tiger by the tail on the maiden. Talk about short coupling, wow! Keep up the good work. John.

[hillbillynamedpossum]

Ive been told Im bipolar, but I just deal with it with Prayer and the support of a loving wife. The medicine that fixes what I have has too many side effects. The last time I spoke to a doctor about it, I told him that if I wanted to go thru life stoned, Id go to smoking dope! My peaks are pretty high but my melancholy peroids are not all that bad. Now that Im getting older, I have to be careful not to hurt myself by over exertion during an up time. A few weekends ago, I fired up my saw and cut down two big trees in the back yard that were sending roots into the foundation of the house. I cut them down blocked them up, hauled off the wood and limbs and raked the yard. It was just then dinner time so after dinner I hauled about 20 wheel barrow loads of dirt from one side of the house to the other to build my wife an asparagus bed. All this was done befor supper time. After supper, I took a shower and sat down on my recliner and couldnt hardly walk for a couple days!

I didnt really time the build to coinside with an up peroid, it just happened that way.

It might be a little twitchy but not too bad. The plane is not as close coupled as it looks. There is some optical illusion in the pic. The chord is 6" on both wings and the tail. The top wing will be (I hope) about 4" forward and about 6" above the lower wing. There is around 11" between the lower wing t/e and the pivot point on the elevator.

If you look at Jennies and Camels and nieuport 17's you will see that the tail is very short. I dont know why this works, but it does.


Possum

[hillbillynamedpossum]

Ive made some progress. Ive just about got the bird ready to cover. Im really proud of the landing gear. It cost about $2 to build the whole set, and they came in at about 4 ounces. If anyone would like I'll do a post on making them.

As much as I hate to admit it, I think this plane is gonna weigh about 2 lb all up. Im gonna use some screws instead of stove bolts when I put it togather after the covering is on. That should save about an ounce.

Any way its been a long day and Im tired.

Possum

[kenchiroalpha]

Hi possum
Thats looks wonderful great job
Cant wait to see more
Take care
Yours Hank

[jungmann1]

That's looking good, Possum! Love the landing gear, specially the wheels and minimalist cross braces. Do you have to count the purchase price of the chew in your budget? I wouldn't, that is a great example of re-use. Very, very cool. John.

[HO-229]

Looks great!

My first impression is it will be a real HOOT to fly with the control surface scheme.

Cheers,
Dave

[hillbillynamedpossum]

I dont use that brand of snuff. The cans were saved back by the shop monkey at work for us to use for small hardware and such. They weigh about .4 oz each and it seems like 3.25" Dubro weels around an once and a half each. The axels are 6-32 all thread and the wheels run on a nylon hub. The nylon fender washers keep the wheel from walking off the hub. The piano wire cross braces are incredibly strong since they never see anything but a tension load. The big wire is 9 gauge galvanized wire. We use it for diagonal bracing on fence corners and it runs about $1.25 a lb.

The struts are made from sheet aluminum that came from the hardware store. It runs $12 for a 12 X 24 piece.


The full flying control surfaces are great to fly with. I,ve learned from trial and crash that you need a good, big servo to survive a less than perfect landing, but a 9 gram servo will do ok even on a control surface this big, IF you dont have a lot of throw. You dont need a lot of throw for full flying tails, but Ill use about 30 degrees, just because Im kinda goofy. Because I am doing this I'll use a full sized servo on the elevator.


Possum

[stuart]

looking very cool possum!!! count me subscribed on this build.

now you have to total up the cost posted so far...its approximately $77 dollars. now i know you only calculate the price depending on amounts used....soooooo,the gallon at $38 dollars will go along way on the next build ya do.

man,if your wife finds out your going to be building 30 more planes just to use up the "tauntin nitrate dope" she'll run rampent through the hanger with a bat...lol...but we'er not going to tell on ya possum.


by the way i am pm'ing a address to send me a bipe when done with this one....lol.....you'll build lots more to keep the rest of us quite. [justkiddingyoursecrectssafewithme]

[hillbillynamedpossum]

Stuart,

The rules say that I dont have to count the whole gallon, just the amount I used. I will edit that post when Im all done and tabulate the total cost. As far as trying to extort a 33" Bipe from me goes, You better wait till we see if this plane will out fly a bowling ball, because at the rate Im goin, It may not!


Possum

[hillbillynamedpossum]

I got the hatch done. The closure will be old-school rubber band over a dowell. I also got the cowling started.

Im pretty proud of the grommets for the pull-pull wires to run thru. I was playing around with some rivets at the shop and the idea just struck me. So after work I went to the store and got a box of 1/4" STEEL pop rivets and knocked the pins out. I figure steel will wear longer than aluminum and wont try to gall. Im going to use "e" strings for the control wires. They are cheap, very strong and very lite....but mostly cheap!

[stuart]

to funny possum, you don't have to edit the supply list my friend,the bipe would use what,a oz or less dope? i never did a tissue covering so wouldn't know. plus i have to subscribe to the other under a $100 builds .

i can't wait to see your bipe finnished,it very cool looking with the deep offset top and bottom wing!and even if it weighs in a little more than you wanted,it sure looks to be a well thought out build. is this all your design or have you done this before? certianly looks like ya got the planning down from experience building.

[hillbillynamedpossum]

Stuart,

This ugly turd is all my doing. Ive thought about it for about a year, and built about 4 generations of foamy bipes.... http://www.wattflyer.com/forums/showthread.php?t=55486 This is the "Possum Holler Bipe MK 4"

Some of the stuff I'm just coming up with on the fly, but for the most part, I had the big picture in my head.


As for experience: Im a pretty lousey pilot, so I have had a BUNCH of experience building


Possum

[gramps2161]

Hillbilly you redneck love those wheels now that's recycling and going green your bipe is looking great.

Did you use bamboo skewers to join the fuse and the tail feathers? At first I thought it was balsa had to do a double take.

[hillbillynamedpossum]

No Gramps, Those are 1/8" hardwood dowells, Maple I think. I couldnt get balsa to bend like that and not get fragile.....at least not the balsa that I have on hand. I wanted the tail section to be bullet proof, and I think that this is as close to "cant bust 'em" as I have come.

Possum

[Stevephoon]

Possum,

I love your work! I've just been fiddling with parts and looking for inspiration on my build. I do like the foam cowl idea. I might need to steal that from you on my build. My initial thought on mounting my motor is not working, but a traditional x-mount with a foam cowl may work.

It's really too bad you disqualified yourself from the contest. You have my vote.

Steve

[hillbillynamedpossum]

Steve,

I think I stole the foam cowl idea from Grasshopper or Larry, But thanks for the kind words! I plan on attaching it with a dab or two of hot glue and hiding the seam with white electrical tape.


I thought it was only proper to not take part in the actual contest, on account of this whole contest was my idea.

Possum

[gramps2161]

Originally Posted by hillbillynamedpossum

No Gramps, Those are 1/8" hardwood dowells, Maple I think. I couldnt get balsa to bend like that and not get fragile.....at least not the balsa that I have on hand. I wanted the tail section to be bullet proof, and I think that this is as close to "cant bust 'em" as I have come.

Possum

Good idea Hillbillie with the dowels that will keep the tail feathers joined to the fuse, and strong.

[hillbillynamedpossum]

The time has come to start covering. The cheap wally world tissue paper is working out ok, but it has a lot of fine wrinkles. I hope that I can get them all shrunk out with the dope. I forgot to order dope thinner when I got my dope....what a dope, huh? So I had to go to the parts house and get raped for a gallon of reducer. The poor kid there thought I was off my nut when I opened up a gallon can and sniffed it to make sure it was the right stuff! I cut my dope with fast laquer thinner to tack down the tissue and it REALLY blushed on me, but the dope Ive used that was cut with the reducer is not trying to blush.


I went to the LHS to get me a balsa stripper and it hasnt come in yet. While I was there I picked up an american made airbrush for $65. I think its called a panash or something like that. Any way, Im going to play with that some today and see what happens. I tried spraying dope with it. BIG MISTAKE! The fumes like to did me in. Its too cold to use my paint booth, and the vent setup I have for my doping area was designed for dust collection, not overspray collection. It works well for the light fumes that come up when I brush, but not massive fumes from overspray.

If any one wants, Ill post some instructions and ideas for a cheap to build dust collector.


Possum

[hillbillynamedpossum]

Before I forget, I wanted to mention that befor I did any wood prepping, my frame weighed 6.4 oz. After I covered it my plane was 7.2 oz.

My Chew can wheels, hubs and fender washers weigh 0.6 oz each... Dubro 3.25" wheels weigh 1.6 oz each!

I got the servos in, the exit holes cut, the tailfeather control horns made and installed and everything done back there.

Another thing, if you want a fast evaporating thinner for nitrate dope, use acetone, not laquer thinner, and not the $35 a gallon crap from the parts house!

Possum

[hillbillynamedpossum]

I got some color shot on tonight with my new airbrush. The paint job looks pretty good but my color choices SUCK. My wings look like some stupid stoner flag. On the next go-round Im using a darker green and just painting the wing tips.

I really like the Idea of red on the port and green on the starboard......but I got to get this color plan down a little better.


Possum