Thread Tools
Jun 28, 2004, 06:00 PM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP
Alert

"Pseudo Pa-Nee"..The "NO-PLANS" Cropduster (PART2)


The first part of this thread is Located Here.. https://www.rcgroups.com/forums/show...16#post2266816
It was getting quite long,and I was concearned about all the photos in it, so I started a "Part 2" thread. If You like what You see here, Look at Part 1 for the beginning of the construction... Bob

SPECIFICATIONS:
LENGTH: Approx28" tip of Spinner to tail

SPAN: Approx 40"

WING CHORD: Approx. 6"

FUSELAGE WIDTH: (at largest point 4" LOT's Of equipment Room! )

WEIGHT: Approx 9 -10 oz. (with IPS & Qualcomms.. Li-Poly approx 1 oz lighter )

POWER: IPS A , 280 geared,300 geared,to DD or geared 400 (pretty much anything You want.. Plenty of room for about anything! Don't know ANYTHING about "brushless"..too expensive for Me, so You are on your own there.)

RADIO FUNCTION(S) 3-4-5 channel (3-ch beginners, 4 with strip or "scale" ailerons for bigger motors. 5-ch for a "duster" using talc powder & servo-controlled hopper valve system, (something like the old Sterling stearman crop-duster).."too ambitious" you think? )..Bob the "Builder" says: "Can We build it? Yes We Can!"

DON'T Let it SCARE You! It MAY look "complicated" but it's really not. Tom (TooTall) has been building along, and this is his FIRST scratch-build! (I can barely keep him behind Me! ) I even furnished him with a molded cowl from my plug tha actually FIT, and fit very well! So, even though our builds are many miles apart... You can build the identical aircraft from the info contained in here. (it also means if you need a molded cowl, and don't want to do the plug-making, I can help! ) I MAY, even offer a "basic" set of hard-copy templates, and perhaps even a moulded clear "greenhouse" Canopy/cab/door section to eliminate what I consider to be the "toughest" part of the build.... Bob

ANOTHER NOTE: I thought I'd update the first part of the PART 2 post... We are now "finishing-up" at the other end, and the weight is a bit much for an IPS A gear. However, It should be ok with a dual geared IPS, if You have your heart set on it. Since starting this thread, I've broken into the "low-range" of brushless power using a $4.00 gobrushless.com CDROM motor & 5 x 5 x 1 magnets. (details further in the thread) AUW with motor & Li-Poly batts will be about 12-12.7 oz. RTF. (without hopper & with ailerons) and around 14.5 to 16 oz with hopper & load. If You don't have a brushless set-up, realistic power can be geared 280-300-350-400. depending on your final weight, and choice of batteries & gear. Bob
Last edited by Demon-Leather; Jun 28, 2005 at 02:56 PM. Reason: UPDATE...
Sign up now
to remove ads between posts
Jun 28, 2004, 08:14 PM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Fuselage Construction..Continued


The first photo shows spruce clamped to F-3 from previous post...

Now cut & measure You a piece of 1/16" X 1/2" ply piece to fit SNUGLY in between the runners holding F-2 in place. This will be the wing dowel mount, and it must be TIGHT & FLUSH against both F-2, and the runners holding it. You need to install it 1/8" BELOW the top, so You can place a 1/8" sq. stick on top of it, and up against F-2....when happy with the fit, clamp with clothes pins I let dry..

Go to station F-3 and measure & cut a 1/8 X 1/8" sq. stick to fit the former at the fuselage top(which is your bottom,pinned to the board..My pen is resting on the 1/8"stick) and epoxy into place on both sides NOTE: MAKE SURE you drop the sticks on the frame rails enough to leave room for the 1/32" X 1/4" ply strip on top... this will be installed after unpinning the frame from the board..

Install the 1/8th" sq stick on top of it with epoxy against F-2 and clamp firmly, Let dry, then add your 1/4" gussets,(again, sanding one leg to be flush with the stick, but following the angle of the fuselage)
Jun 28, 2004, 08:35 PM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Continued...


Now, we go to the rear tailpost section, and relieve your sides to accommodate the tailwheel bracket (If you haven't checked the Tailwheel assembly post lately, there is an amendment to it that You will need to do.. If You have previously built it)

Once You are happy with the fit, You can mix some 30 minute epoxy and install it, clamping the tailpost together, trapping the bracket inside,. it should lay flush in the 1/32" relief You cut in the 1/8" X 1/8" frame rails.. DO NOT relieve the fuselage SIDE skin!. If the bracket is too big,.. Trim it off to fit, no one will see it, as it will be covered with the 1/16" sheet bottom. The tubing SHOULD be the only part visible..and that can be in the skin just a bit, but the wood should NOT effect, block, or bind the action of the wire.

Draw your sides in to meet your angled lines that You drew from the tailpost, up towards F-3, and pin them, angling the pins to hold it down flush on your board.
Check to make sure the tailpost seam is 90 degrees from the board. if not, adjust till it is, as this will keep your rudder square and at 90 degrees when we install it later...

Measure the distance between the two sides at the first set of fuselage uprights ( the first two 1/8"sq sticks from the tailpost) and make it fit snug by angling each end.
Once it fits perfectly, make another EXACTLY like it, the same size,same angles
Jun 28, 2004, 09:31 PM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Continued...


Place the first one at the bottom and find you two heavy things with 90 degree sides & taller than your fuselage sides (Note how the bottom is pinned & straight, while the top is bowing out?... we need to draw the top in before applying the CA) I used 2 1-pint cans. not the greatest thing due to the lip on the bottom, but they were handy. If You have a LIGHT "C'-clamp, or other type clamp that is light duty by all means, use it.
once a good fit is obtained, and the sides reasonably square, apply thin CA.. when that has dried, install two 1/4" gussets. It's a VERY tight fit for My large "hamhock-hands, so I used needle-nose plyers to place mine.
Now do exactly the same thing to the top (actually bottom) end.. check your sides to make sure You are qsuare, check the fuselage to see that it is still pinned firmly, and check your tailpost alighnment for 90 degrees...

Go to the next upright station and repeat the above procedure...checking pins, & alighnment again too

Ok,.. NOW comes the best part!.. unpin it, & flip it over.... We need to yet make our turtle deck formers, cut some 1/8" sq slots for some sticks to brace the 1/16" sheet, add a few more gussets, some more reinforcement to F-3, and make formers & a hatch plate.. but the "tough-stuff" is Behind us now! Looks pretty BIG, doesn't it.. should feel pretty light too!

Take the piece of 1/32" X 1/4" ply you cut erlier, and cut it to length to fit across the top of F-3 and it's 2 1/8"sq. sticks at each side.. Epoxy & clamp well.
Jun 28, 2004, 09:48 PM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

The Wieght, And a Cowl-Shot!


That should do it for now (I'm Tired! )
I weighed the fuselage up to this point, and it comes in at 1.7oz... Not to bad eh?

And I couldn't resist slipping a cowl on it!.. This is not the one I'm going to use.. I'm going to make one for You and photograph the process, so You can turn them out as fast as You can dring the soda! >BURP< oops heh.. excuse Me!

Wieght with the cowl,.. unpainted is 2.2 oz.. ok,.. but our 4.8oz allowed for the airframe to achieve 9.0 oz with the IPS is getting consumed rapidly!
For You using a Li-Poly pack,.. you will have a bit more than an oz to play with on that 9 oz.. remember, My Li-Ion pack wieghs over an oz more..
Jun 29, 2004, 04:17 AM
victim of the system
TooTall's Avatar
Dang , work is really starting to mess with my build time...I am lagging behind a bit but I will catch up before or on the weekend ...I have my cowl block formed and started shaping ...still needs some sanding ...need to fabricate my tail wheel assembly...I have the other parts and pieces , including the fuselage print...just need to get a little sleep and then get busy before going to work tonight ....That is looking sweet Demon....I am excited to get on with my build ....I have sent you the prints for the Clipper and when you receive them ,, then weight may no longer be a factor for your pawnee.....thanks for your time and effort on this build thread....Tom (there we go , now I am subscribed to part 2...you can't shake me that easy you know)
Jun 29, 2004, 04:22 AM
victim of the system
TooTall's Avatar
Just looked back thru and was reading some of your posts....heck if you ain't gonna use that cowl then sell it to me ...hehe ..
Jun 30, 2004, 02:17 AM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Cowl Plug "Extreme Make Over"......


Tom,.. after sending Me all that stuff, I'll be more than happy to plug You one up FREE! Here's a couple photos of My Cowl "Extreme-Make Over"
I flattened the bottom out to better follow the bottom fuselage line for what I think is a much more "Piper-ish" shape (looks a bit like a Super Cub cowl now) I contacted the fellow who is doing the 1/5th scale gas job in Europe and he gladly gave Me permission to post photos from his website in this build thread (if You are watching, Thank You VERY much Koos! ) I posted some of Koos' 1/5th scale Pawnee underneath My cowl photos.....
These are "before & after" shot of the cowl.. one of the cowl I plugged previously, and the "new-look" of the old plug Bob
Last edited by Demon-Leather; Jun 30, 2004 at 02:37 AM.
Jul 01, 2004, 09:18 AM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Front Fuselage Top & Hatch...


Let's begin by making our instrument panel former.( by the way, I have a Beech Bonanza instrument panel we can use for the Pa-Nee that is roughly the same shape, .. I just have to "find" it..)
This is a very simple piece to make,..1/8" wide X 3 7/8" long. If You have trouble with it though, You can use the photo and print it out to match the dimensions that are on the balsa. The only thing that has to be "precise" on it are the notches, and all You have to do is find the center of the piece, and make the inside dimension of the slots the same as your other pieces that You downloaded.
Note**: since we're talking about the notches, You need to deepen them to 5/16" instead of the 1/4" stated.. best to do it now, before you forget.
Measure exactly 1" from F-3 on both sides, and install the instrument panel former to the FRONT of both those lines..should be sitting even across & notches snugly on the side rails.
The "other" formers You need, You already have on F-2 & F-1...(well, except one, but that's coming) You just need to trace them on a piece of 3/32" or 1/8" sheet (if You have enough left from building the tail feathers that's fine.) Trace them flush down on top of the frame rails. It doesn't take much balsa, but will dramatically increase rigidity & strength with a bit of epoxy!

Now cut 2 pieces of 1/16" sheet 7.5" long, and 1 3/8" long ( I know it says 1 1/4" on the balsa,. but I ran out of sheet at the very end at the instrument panel former, and had to "splice" a 16th" there because of the taper.. You won't have to)

Place both pieces in HOT tap water in a pan, or jar, and let soak a few minutes......If You use a pan, weight them down, a jar.. use a lid. They'll pop-up like lifejackets if you don't.
NOTE*** When you deepen your slots in the formers, don't forget to deepen the cutaway in F-2 the extra 1/16" as well....
Last edited by Demon-Leather; Jul 01, 2004 at 09:22 AM.
Jul 01, 2004, 09:56 AM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Sheeting & Hatch Rails....


For curving your sheets you will need a broom or a mop handle ( I used a metal mop handle) and several standard type rubber bands (the small ones they use in offices etc.)
While wet & warm, wrap your 1/16" sheet pieces around the handle as squarely as you can vertically, and close to the top of the handle. You can put them right next to each other, just don't let them overlap (see photo) Make the rubber band tight, but not tight enough to cut or dent the wood,just hold the curve of the handle 7 or 8 will be fine.
I was experimenting & racking My brain trying to discover an easy way to get the bands on the mop handle & then get My rather large fingers in them to expand & slide them over the sheet. I even went so far as to pound a small flat at the top of the metal handle, where I could get a smooth butter knife underneath them & aloow My finger to take over.. My wife, looking at the condition of the handle, gave me an evil look, walked over and wrapped a rubber band around 2 of her fingers. Then opened her figers, tranferred the band to 3 fingers on the other hand, expanded those fingers and simply went over the top & around the balsa...easy as pie! Then, promply walked away, shaking her head in a huff... I tend to over-think things sometimes I highly recommend her method! Anyway.. let dry while building the hatch rails & installing former braces etc. and when you take them off, they will look like the photo.

Ok make 2 pieces of 1/16"x 5/16" x 12" these will be the hatch rails. install in place as shown, and check the fit. If they are bowed anywhere due to misalignment, fix it now. You want them as straight as possible. Look down the front to spot waves or twists. when happy with the fit, CA in place & trim off the excess( & save it)

With that done, make 2 of these small formers in the photo. You can print it out & size to the measurements, or just lay it out. Come from the back of the istrument panel former 2 1/4" and place them there...this is not too criticle, so if they fit better 1/8 or so inch fore or back, that's fine, as long as the rails are straight. I was going to put a gusset inderveath it to the frame, but when the sheet was install I was satified of it's strength, You may gusset it if You desire, or round the edge to be more eye appealing.. another option for you!
Last edited by Demon-Leather; Jul 01, 2004 at 08:39 PM.
Jul 01, 2004, 10:37 AM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Continued....


When installing your pre-cuved sheet, start at the frame sides & glue it flush with the sides, then, just press into place & glue the rest while upside down, then trim, sand a bit.. that was pretty painless... If your sheet gets split, cut or cracked, don't replace it.. just press it back together & Thin CA it. It's also a good idea that after it's in place, to run a few drops of CA in the inside while upside down. let it flow in each compartment, it will make that sheet VERY tough, with little weight gain!
While we have it upside down.. It's a simple matter to sheet the chin. Trace your 3/32" (or 1/8" former, & transfer the center mark to it as well.. Go to the 1/8 x1/8" stick running across the front of F-2 and put a 1/8" notch using the centerline on that former.. cut a 1/8" sq. stick to fit snug & CA.

Once that's done, take a piece of sheet with one straight side (grain running lengthwise to the fuselage) and butt it up to F-2 & CA into place. Flip the fuselage back over, form the sheet with hand pressure to fir the rest, CA from the inside, trim & sand (another "no-painer" hmmm starting to look a bit like a plane now...
Jul 01, 2004, 10:58 AM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

Continued....


The first photo is of the chin sanded..Looks nice & matches the cowl plug GREAT!

We now have to make the part of the top deck that the canopy will mount to, and the hatch rail end. Measure back 1 1/4" on both sides, and install a 5/16" rail piece across there,just in front of the lines & CA into place.

Cut & fit a piece of 1/16" sheet to fit, bring the end over the top of the rail, in the front, & don't worry about the back You can trim that after installing it.. just make sure it's a good fit on the sides & front.

Now,.. check out the room in that hatch! (I've got some HUGE paws too! ) If You can't fit your hand in that one... You need to fly BIGGER planes, or go back to your home planet..
Jul 01, 2004, 12:33 PM
victim of the system
TooTall's Avatar
I AM LIKING IT !!!!! I am to the point of having my tail wheel assembly in place....need to stick up the next 2 formers ahead of the tail and flip it over and continue on....looks like that is plenty of room in the hatch area....will be able to carry enough grits to rid of all the fire ant hills in all of the southeast !!!! Tom
Jul 01, 2004, 01:23 PM
"Experienced-Crasher"
Demon-Leather's Avatar
Thread OP

"Final" Cowl revision....


Ok.. I still didn't think the cowl plug was "quite right', so I moved the lower intake hole down abour 1/8" and added a scoop fairing.. I think that's as close as I'm going to get... I think it made it better..
The last photo is servo taped to the fuselage (Man,.. I'm glad it really doesen't go on there.. I bet it weighs a poind! !)
Jul 01, 2004, 02:42 PM
victim of the system
TooTall's Avatar
yep the new cowl plug looks "alot more better"....and yep you can send me one of those when you mold 'em up....the fuselage is looking great ....I need to get to the LHS this weekend and order up some Trexlers..


Quick Reply
Message:

Thread Tools