3M Scooter Build

[erich]

Have finished the Ray Hayes / Otto Heithecker Challanger, so am now looking for another plane to build. Was hoping to build an Aquila, just love the way that plane looks. But all I got is a rib kit for the Aquila. And while I don't mind building a fuselage from scratch, I got this, 3M Scooter full kit (Leon Kincaid), sitting here, and it's just screaming to be built, can you hear it? Build me, build me.....So.... that's what I'ze gonna do.

If there is interest in a documented build, on the 3M Scooter, I'll be glad to do that. The plane has a relatively modern airfoil (to me anyway, I still think the E214 & E205 are great). Uses a K3311SM foil, which is slightly under-cambered and has a raised entry. The plane has won a number of contests in the late 80's and early 90's. And the best thing is, it's an all wood kit. I'll be doing some carbon fiber reinforcement of the spar however. Just some wraps around the root area. Other than some cosmetic changes on the wing and stab tips, will build it to the plans.

So have taped the plans to building board and am ready to start on the spar system. Please let me know if there is interest in this build.

erich

[ferincr]

Are you going to make us beg??? :D
Fernando

[erich]

Yes.

erich

[ferincr]

ok then...
pleeeaaase??????
Fernando

[Matthias89]

You just finished building your Challenger, and you already begin an other... That's why you're a fantastic builder :D
I'm interested too! Is there an aileron option?!? If not => Are you going to make ailerons on it?!? (As you know, I'm surching for a thermal wood crafter like the challenger, with ailerons, spoilers, rudder and elevator (I'm an aileron lover...)). Maybe I gonna build this kit too if you can convince me :p . So pleeeeeeeeeaaaaaaaaaaaaaaase a ducumented build!!!!

greets,
Matthias

[erich]

Ok...Ok....stop the blubbering, I'll do it. Sheesh, that's the best and whinniest begging I've ever heard. On to the less important stuff.

Matthias

I too love an aileron ship, but am saving that for a Dodgson Camano kit I have. So this is going to be a plain RES ship with dihedral, polyhedral etc. If the Sagitta 900 kit ever gets produced again, it's the perfect ship for you. Lotsa folks have turned that RES into an aileron ship with great success. There are plans available for it but no kit.

So on with the build. And please no more begging, it's embarassing.

erich

[thermalbum]

You just finished building your Challenger, and you already begin an other... That's why you're a fantastic builder :D
I'm interested too! Is there an aileron option?!? If not => Are you going to make ailerons on it?!? (As you know, I'm surching for a thermal wood crafter like the challenger, with ailerons, spoilers, rudder and elevator (I'm an aileron lover...)). Maybe I gonna build this kit too if you can convince me :p . So pleeeeeeeeeaaaaaaaaaaaaaaase a ducumented build!!!!

greets,
Matthias

If you are looking for all wood multifunction sailplanes try the attached link. They sell kits for the Opti-Moose, Keetah and Runaway check the RCM listing. These plans are for 120' full house wooden sailplanes. You need to purchase the plans from RCM however.
http://www.kitcutters.com/

[erich]

Have checked the site you mention (kitcutters) there is very little info on any of the planes you listed, just winspan and price. I have ordered an Aquila fuselage from them but it will be late October before I get it. I guess they make everything up to order. If you send them the plans they will make most any plane, into a kit.

erich

[erich]

Checked RCM plans section and they give a little more info on these planes. The Opti-moose looks pretty good, a 4 Channel all wood glider. Looks like you order the plans from RCM and then kitcutters will make a kit for you, pretty cool.

erich

[thermalbum]

Checked RCM plans sedtion and they give a little more info on these planes. The Opti-moose looks pretty good, a 4 Channel all wood glider. Looks like you order the plans from RCM and then kitcutters will make a kit for you, pretty cool.

erich

One of my buddies built an Opti-Moose years ago- it is a BUILDERS design not for the faint of heart or the impatient. It has the ailerons and flaps actuated by push/pull cables. I would suggest servos in the wings to make thing easier. A majestic flying plane.

The Keetah is the forerunner of Harley Michaelis' Jouster ailerons and flaps etc. A good flyer and contest type ship.

The Runaway is again ailerons and flaps with a T tail . It has a three piece wing. It is fairly straight forward to build, just a 130 inches of it. It did pretty good on the contest trail in the US northwest. The plane was designed by Fred China a great builder designer. He now builds/flies scale sailplanes of museum quality

[erich]

thermalbum

How did the Opti-moose handle? Or is there any way to get in touch with the friend who built it?

erich

[thermalbum]

I lost touch with him a few years back.

From what I can remember it flew very well nothing nasty or surprising. It wasn't designed for monster zoomies or standing on the winch pedal when launching. As I noted it is a complex and well engineered sailplane that requires some patience. The structure is more akin to building a vintage scale ship than a contest model. Maybe someone out there in cyberland has the magazine article and could provide it to you.

[thermalbum]

There is another thread called "Built up 3 meter" with some info on the plane from me (essentially the same as I wrote here) and some stuff from someone who knows the designer

[erich]

Thanks Thermalbum, have ordered the plans for the opti-moose (what a stupid name), from RCM. Would love to get the article. But at any rate can't wait to see the plans. As far as zoom launches, have never done one. Was in only one contest back in 86 or so. Almost everyone had built up ships, except me I had a foam core full house (Dodgson Windsong) plane. Yet just about everyone was doing zoom launches except me, I'd float up and would actually have to dive to get the tow hook off. The other contestants must have thought, I was nuts, and they were probably right. Believe they were using 6 volt winches back then. Usually use a heavy duty histart to launch. So this plane sounds just right to me.

erich

[thermalbum]

Your welcome - enjoy the build.

[Matthias89]

The Sagitta 900 looks a verry nice glider! But is it a full wood kit? The Osprey 1000 looks also interesting, this glider looks like the Challenger (VERY beautiful). But is there a kit of it, or only a plan? Maybe Ray Haves can give me some information.
Now I've got 3 choices =>
- Challenger (because it's a beautiful glider who won thermal contests)
- Osprey 1000 (because it looks like the Challenger)
- Sagitta 900 (looks like a glider who's a bit aerobatic whit ailerons on it :rolleyes: )
My preference goes to the Challenger. The only problem is the money :eek: ...
Because I'm 16 (still at school) and a 1:1 gliderpilot (1:1 gliding is expensive), I need to save some money for my RC gliders :rolleyes: ... As soon as I've got the money I'll buy one of those 3 gliders (probably the Challenger), so probably it will be a winterproject.

Now back on topic

Matthias

[erich]

Well to start the plane. I wanted a plane that would fit in my car a little easier than the Challenger (6 foot wings), that looked good in the air, was an RES, and needed no computer radio mixing, plus could take moderate zoom launches. The Scooter with some carbon reinforcement on spar system seemed to fit perfectly.

Got to give credit to the Houston Hawks (and probably more specifically Jack Womack) for the idea of building spar separately and then gluing to bottom sheeting. This way of building a spar makes it relatively easy to add kevlar or carbon thread wraps to root area of spar.

The kit is very complete and has some well machined parts (laser cut). The root ribs are well cut 1/8" ply. Comes with two ply shears for root area one about 10" long another 6" long, which is to be the front shear. The front ply shear has a 3 1/2 degree angle cut on one end (which is the incidence angle of inner wing). The rest of the spar is two 3/8" x 1/8" spruce cap pieces and a 6" balsa full width shear, which goes in right behind brass tube area. So given these parts was able to build the spar fairly easy.

Used a big aluminum 4' measuring stick taped to my bench, to align the bottom spar cap against. Marked the proper location for 6" balsa shear and used titebond to glue that in. Added top spar cap making sure top and bottom caps are aligned. Then added front shear web, the one with the angle, leaving 1/8" gap at root area for root rib. After which did some trial fitting of root rib, brass joiner tube, and spar.

erich

[dr.E]

Just build the fuse. We have the coordinates for a CNC cut foam wing and stab. Builds in a Jiffy :D

Another good design is the Leon's Heat Seeker, there is an outfit that makes a FG fuselage.

Next project is an Astro Jeff with foam stabs and wings (Blue foam on the center panel and white on the outboards......)

[erich]

Don't care for fiber fuselages, and am not overly excited about foam wings. While I do enjoy thermaling, for me most of the pleasure in RC planes is building. And seeing as I don't even know you (dr.e) why would I give up my joy of building, to you? This is not meant to offend but to "enlighten and inform". Build to continue shortly.

erich

[erich]

Ready to glue in brass tube, root rib and rear ply shear. Used 30 min. epoxy for this. Mixed up two batches of epoxy one with micro-balloons for area around brass tube, and one straight for area behind tube and against balsa shear and spar caps. Used almost all the clamps I got and made sure everything was square and aligned. To align brass joiner tube what was required was to have it inserted in root rib and have outboard end just touching bottom spar cap. Then added balsa filler pieces (provided and cut to size) above and below brass tube. Made sure to add enough epoxy to fill all voids around tube. Lot of the epoxy ended up getting squeezed out. Before glue was completely cured took off clamps and trimmed all the oozed out epoxy before it got hard.

Yee haw, off, and to the races

erich

[dr.E]

Erich..... You're only a stranger once.

I have finished my Challenger just last week and I'm ready to cover it this week. Love woodies :D

Leon Kinkade lives in Florida and he just finished up his latest Heat Seeker Electric variant.

I've built all wood Skooter and they do fly nicelly (My latest will be a couple of WindFrees while I iron out the Astro Jeff composite build)

The idea of foam/fiberglass came actually from one of my flying "gurus", he has built countless woodie variants but he is pushing 80 plus years young and he feels that he would rather spend more time flying than waiting for Titebond to dry.......

[erich]

dr. E

Let's see a photo of your Challenger (after covering). Glad to hear about your Scooter. Hope mine flies as well. Got the wrong message from your post (#18). Seemed as if you were tempting me with some foam cores. If you run into Mr. Kincaid, please tell him, thanks for a well thought out design. Hope he doesn't mind my doing some small changes (ie. carbon spar wrap) to his beautiful plane. Tell your flying guru, if he applies the titebond before going to bed he won't have to do as much waiting. Have built quite a few planes in my time, and have found that if one keeps anticipating the end product during a build, it will seem to take forever. However if you just look forward to completing the next step in the proccess, it goes quicker and is enjoyed all the more.

I remember my first build, a Sig Riser, took about a week to build (worked 8 hrs a day on it) but, to me, the build seemed to take forever. The Challenger just completed took 7 months, but seemed to go quicker than the Riser. To each his own is very true, and my own is to enjoy the building of wooden planes.

Green air.

erich

[Joe Minton]

Leon Kincaid
Leon has retired and is living in Colorado Springs, Colorado. He gets to fly on the parade grounds of the Air Force Academy. Nice grass for landings!

I have one of his Scooters (three meter) and it is a wonderful sailplane. I can launch it reasonably hard and, with the CG. back a bit, it reads lift very well. A couple of clicks of down and it comes home from downwind quite well. I am a sport flyer but the Scooter 3M is clearly competitive (RES).

It is a beautiful design, as are all of Mr. Kincaid's, and a truly excellent performer. It has won a number of rather intense competitions.

Joe

[erich]

Thanks Joe,

Sounds like I picked a good plane to build. While I do like to savor the build of a plane, you got me wanting to get it done and flying. Am wondering if perhaps DR. E is speaking of a different Leon Kincade. Oh well, on with the build.

erich

[dr.E]

Terry Good (Walt Good's ) son was visiting his mother in Florida. Leon lives close to her house (Port Saint Lucy) ,as a matter of fact, Leon gave Terry one of his Scooters and he keeps it in his mother's house.......

Leon was in the process of submitting the construction article of the Heat Seeker (he took a couple of pictures of the Scooter and Heat Seeker side by side) hopefully I can get some to show.......

BTW....... I'll post my Challenger pictures on the Challenger thread ;)

[erich]

Back to the build

Would have preferred wrapping spar with kevlar thread. Other than the fact kevlar is stronger like the looks of the kevlar better (yellow). But had a bunch of this carbon fiber thread, kicking around for awhile now, so used that instead. Did very close wraps for about 2" then started spacing out wraps a little. Wrapped out to about 8", which is twice the length of brass joiner tube. Hopefully that will let me get away with some easy zoomed launches.

erich

[Joe Minton]

RE: Where Leon Kincaid lives:

My knowledge is a couple of year old; from a time when I exchanged a couple of letters with Leon. At that time, he lived in Colroado Springs -- I stand corrected.

In the September 2000 issue of S&E Modeler (now Quiet Flyer) Leon published his "Back-To-Basics S400" e-powered 60" glider. I was awed at the detail excellence of the design. I literally take the plans out and stare at them from time to time just to remind myself that excellent design can be, well--- elegant. Eventually I'll build that plane.

I am not a seasoned pilot but I can keep my 3M Scooter up as long as anybody in the club; only an "AVA" or Don Northern gets higher in any given thermal!

It is sad that the 3M Scooter has not received the attention it deserves. It is, perhaps, the best of the pre-composite competition sailplanes. With a bit of carbon, it can be launched like a Gemini MTS (the strongest all-wood spar ever) and with its K3311 airfoil, similar to the Selig S3021, it penetrates well enough to get home from low and downwind. It is a better plane than I am pilot.

There should be more Scooters in the air.

Joe

[oracle_9]

Wow, erich, your challenger thread was awesome, I look forward to your scooter project, as I am possibly thinking of making this plane too in the future.

There are some guys at my club who fly the Scooter 3M. Flies very nicely.

Keep up informed about the kit you ordered from kitcutters too.

[erich]

Haven't ordered a kit from kitcutters yet, just ordered the plans from RCM.
For now going to concentrate on this Scooter, starting to sound like a really good
design, hope I do justice to it.

erich

[erich]

Cut and placed bottom LE sheeting to plan. Also TE sheet, which is basswood in this case. This wood is a bit harder than balsa, but should hold a sharp edge better. Took awhile to sand the sharp feathered area at TE, which accommodates the top TE sheet (balsa). Since this is a slightly under-cambered airfoil needed to shim up the inner TE piece a little, used small cardboard shims (as suggested in plans) under TE piece. You can probably see them on second photo, they're just under inner edge of the basswood TE piece.

Now it was time to glue in spar assembly. Used 5 min epoxy mixed with micro-balloons in the area of the carbon wraps and Titebond on spruce bottom cap piece the rest of the way out. Had to work fast here so had everything setup to go. Second photo was taken 6 minutes after I mixed the epoxy. Hope it's in the right place, because it's there for keeps now. The rubber bands and spacers are the only way I could figure to hold down outward part of lower spar cap, since bottom and top spar caps are kinda free-floating outward of the ply shears.

erich

[erich]

Cut and placed the rest of the bottom inboard area sheeting. Made a paper template to get the sexy looking curve on outboard end of this sheeting. Most of the spars will be glued to sheeting and rib caps using CA, but the root rib being made of ply I used titebond to glue it to bottom sheeting. Added hardwood block between spar and root rib for wing retainer screw eye, using 5 min. epoxy.

erich

[mhodgson]

Nice to see some real building going on.
I've been interested in this design since seing the 2m version as a plan in one of your mags several years ago, but never quite got around to building it.

Recently I've seen a kit available for the 3m.
http://www.soy.on.ca/scooter.html
Don't know if anyone has experience with this kit or the manufacturer.
I enjoy building from scratch (plans) but might just try this kit for a quick build project.

[oracle_9]

The owner of the company who makes the kit at soy.on.ca goes to my flying club. I seen him first hand fly his scooter 3m. Another person also flies one too, but his is an old one!

For a picture of his...
http://www.thermalmusic.com/cogg/

look under the "gallery" section, and for a photo with the heading "Jack getting ready for the contest July 6, 2002", and "Open contest Aug 4, 2003" (bottom right, the red/white winged plane)

[mhodgson]

Thanks for that.
The more I see it the more I'm tempted
Now I wonder if I can persuade she who spends all my money to buy me one for my birthday in October!

[erich]

Good to see, and hear of others' Scooters, keep em coming.

Glued in the 4-1/8" balsa ribs. Used thick CA where rib meets spar and thin CA at sheeting joint and TE joint. Where ribs touch carbon wrap did a little sanding of rib to make up for the extra thickness of wraps, hey, shouldn't hurt, and takes no time at all. Made sure to press down on rear part of ribs when gluing to bottom sheet, so sheeting gets pulled up into the under-cambered ribs, very simple to do and effective.

erich

[mhodgson]

A pain, the undercamber of ribs. Since taking a dislike to cyano I now cut a set of foam blanks (using one of the ribs as a template) to use as a mould, board, and to press the top skins on. Simple white foam ones and they make great beds when covering and storing the finished model. Nothing worse than putting your nicely sanded wing on the board and finding a rogue piece of wood, glue or tool has jumped under the wing as you put it down.

I build almost entirely with white glue, balsa cement and epoxy these days. Cyano is for repairs on the field.

[erich]

mhodgson,

Hey I like the idea of using foam, under the wing. Will keep that in mind. In this case there is very little undercamber, just used some small card board shims. I use mostly aliphatic except in places where you pin balsa over sheeting (like ribs). Haven't found a good way of wicking titebond, in these areas, as you can with thin CA. Only other planes I ever built with undercamber (E214) had foam cores with balsa sheeting. They flew great (Dodgson: Windsong, Pixy and Pivot), had flaps, and ailerons. While I enjoyed flying them, did not enjoy working with the foam cores. Nevertheless they flew so good, ended up building 4 planes of this type.

erich

[erich]

Added lower rib cap strips. Used titebond where the meet the basswood TE and thin CA at balsa LE. Am sure everyone has things they like or dislike doing in a build, for me a favorite thing has always been, adding cap strips, kinda nutty....huh. Well it's starting to look a little bit like a wing.

erich

[erich]

Installed next four ribs, these are 1/16". Starting with bay 6 using 3/16" vertical grain balsa as shear webs. My apologize to Mr. Kincaid, the plans call for 1/16" balsa shears attached to both sides of spar caps. In this plane I put 3/16" shears between the spar caps, a little more difficult to get the exact heights of, but uses less glue (so less weight). The kit comes with the most beautifully, bundled pre-cut 1/16", shears, too, hated not using them.

erich

[erich]

Added the rest of the ribs, except the 1/8" rib W15. Will add that when attaching wing tips. You can see in photo 1 that the top cap still needs to be glued to shears and ribs. The nice thing about making the spar this way is, you can see if there are any gaps or high points on the webs and by lifting spar cap you can add wood or sand down to get good fit. Used titebond on all shears and ribs where attached to spar caps, and thin CA where ribs are glued to rib caps and bottom sheeting. In last photo top spar cap has been glued in.

erich

[erich]

Glued in false LE piece. Planed bottom to follow LE sheet contour better, then planed and sanded top of false LE piece, so as to follow rib contour. Added sub spar and spoiler seat. Cut notch in seat, to clear spoiler cord. The pre drilled holes for spoiler tube were all in the right place just needed to widen a few out, to accommodate curve of spoiler tube.

erich

[mhodgson]

Now I remeber why I when for crow brakes, I could never get those blasted spoilers to fit and work properly. I think I'd be tempted to put a servo in under each spoiler with a short rod to open and close them.

Wonder what Leon would say if I put flaps on the inner panels instead???
There I go changing a perfectly good design again, must stop doing that!!!

[erich]

Have always used cord, and rubber band returns on spoilers, had no real problems. If you use the tube / toothpick at the spoiler end, as kit suggests, you can then lengthen or shorten the string in very small increments to get equal opening of blades. It's also the way it was done on the Sagitta 900, awhile back. Leon's probably got flaps on his. Just my opinion, but flaps on this kinda airfoil would probably work great.

erich

[mhodgson]

Yeh, have the Sagitta plan. For some reason I could never quite get it ti work as well as I wanted, or get the spoilers to fit cleanly. I guess the brain cells that I would use for that have been fried by too much dope and balsa cement as a kid.

Speaking of flaps, I'm modifying my Bird of Time (it needs a rebuild and is way too light) to have flaps as I 'forgot' to add spoilers to it and it is a pain to land.

About the Scooter- what size are the joiners?

[peachtoo]

I am building a Scooter , found on the curb for the trash man by a friend. The wing was the worst as I misplaced the building instuctions that were printed in 1991 from Model Aviation (July issue) and wandered around in the dark for while. 12 pages, beautifully illustrated. Some of the pics were not too good, as this is an old Zerox copy, but the illustrations are great. He also has dim. for flaps, which the article author advocates.
It is not a "Quick build" as each wing has a 157 items. I used 30 min eapoxy on the tube box assemblies and filled the "box" containing the tube with a West systems filler and epoxy to fairly stiff mixture. I used modified snap clothes pins to hold all together while curing. I got all ready and did the entire assy in one shot. I did have the tube/root rib assy done before hand.
I don't know about building the fuse. as that, fin, and rudder were very expertly done before the kit was abandoned. Included were well done alum. templates for the major ribs with all holes, etc. Also main and tip rib pattern for planked wing. I have a problem now in that after sheeting the leading edge is too thick on the outer panel and there is not enough wood to sand to shape. I may add one more piece of l.E. wood to get the contour back. I ncluded in the kit were well made lead filled 1 oz brass tubes for wing wts.- 22 in all. Did your kit come w/building istructions? If not I could email mine to you. I didn't build in flaps but put in the wider TE planking so I could add later.

[erich]

mhodgson,

Well there's the difference, I never used dope, only inhaled balsa cement. So my, spoiler building brain cells, are probably only half fried. Which could actually be worse...
In re your BOT, I can see where building too light might be a problem, oh well, can always add lead.

The main wing joiner is 5/16" x 11 1/2", but I think that may have to be ground down somewhat. The rear (alignment) joiner is 3/32" x 6". In photo: spar, ballast tube, main joiner, rear joiner.

peachtoo,

We must have quite different Scooter kits, mine has instructions but no pictures. No aluminum templates and no brass filled lead tubes, has rocket tubes for making ballast tubes. Got this kit from the manufacturer (spirit of yesteryear) about two weeks ago, so it's fairly new. Anyway good luck with fixing your plane, looks to be a good one.

erich

[erich]

Added spoiler tube, and top TE piece. Used titebond to glue top TE to bottom TE piece, and thin CA along ribs. Will probably only glue spoiler tube in one place since the curvy route it takes through the ribs seems to hold it in place nicely.

erich

[mhodgson]

peachtoo


It is not a "Quick build" as each wing has a 157 items.

I have been know to build this sort of model from scratch (no kit just the plan) and have it in the air within 2 weeks (my record is 8 days when I built one to a deadline for someones birthday), and that's with white glue not cyano.
But I was single at the time.

Tend to take a bit longer these days but reckon the kit could go together in a couple of weeks no problem, particularly if the parts are all so nice cut out for me.

[erich]

Attached top LE sheeting. Needed to sand a shallow 3/8" wide groove where sheeting meets carbon wraps on spar, used a 3/8" sq. piece of balsa with sandpaper glued to it, to do job. Used 30 min epoxy on spar wraps and titebond on ribs and rest of spar, had to work fast so titebond didn't dry out, a small brush made applying the titebond a little quicker.

erich

[mhodgson]

This is another place I now use foam blanks. I sometimes thin the glue a little with water to make it flow a little better, add the sheeting and tape in place, particularly along the LE. Then put the foam blank on and turn the whole lot upside down. That way any glue squeezed out at the joints stays at the joint and makes a fillet rather than running down the rib or spar. It also means I can add plenty of weight to bend that skin round the ribs.

I used to iron the balsa skin on but stopped when I started glassing wings and went to softer wood.

[erich]

mhodgson

So what do you do, leave the foam inside the wing (between sheeting and ribs)?

erich

[greyhound flyer]

Eric,

I think he's saying that the foam bed is a "shuck" that is placed on top of the wing and then flipped over onto the bench so that the wing is now on top (and weighted down). This allows the glue squeeze-out to make fillets against the ribs instead of runs. And the foam presses back against the sheeting to keep it tight against the ribs.

--GF

[erich]

--GF

Have you ever had sheeting rip off of a plane, cause the glue didn't hold? Me neither, seems much ado for no gain. I try never to put that much glue in a plane that it gets squeezed out to "make fillets", TO ME, that just adds unneccessary weight. My method, to keep the sheeting tight against ribs, is to use bags filled with lead shot. Works fine, and keeps wing flat on building board while drying. Am usually trying to use as LITTLE glue as possible. But then again if one's aim is to make a plane that can be flown into brick walls without breaking, have at it, there's room for every aim, it just isn't mine. Peace brothers.

erich

[greyhound flyer]

Eric,

Agree wrt glue weight. A trick that the indoor freeflighters taught me was to "preglue" joints with with a thin layer (thinned or not) of Duco, Ambroid or aliphatic, and then glue the joint for real with a second "coat". The acetone in the first two melts what's already there and gives a good bond to the porous balsa. Of course, those are drops of glue applied with sewing needles and the like. :) I also learned from a weight-obsessed RCer to use aliphatic on wooden planes as much as possible since it's dry weight is super light and it's very strong for what we build. You are right-excess glue is almost always excess weight.

I think either way of holding sheeting agaist ribs will work. I'm a big fan of lead shot for holding things down--directly on top of or cradled in foam.

I just need the time (and dedication) to build that you have. :)

--GF

[C-MIC]

You just finished building your Challenger, and you already begin an other... That's why you're a fantastic builder :D
I'm interested too! Is there an aileron option?!? If not => Are you going to make ailerons on it?!? (As you know, I'm surching for a thermal wood crafter like the challenger, with ailerons, spoilers, rudder and elevator (I'm an aileron lover...)). Maybe I gonna build this kit too if you can convince me :p . So pleeeeeeeeeaaaaaaaaaaaaaaase a ducumented build!!!!

greets,
Matthias

I have not briefed thro this thread as I write, but I think the Cloud Bound 4 of Ray's Skebench.com should meet your requirement completely.

I bought two almost 1 year ago, but just get some time to complete the installation of servos..

The kits are quite good in quality, thou this cb4 is not recommended for beginners which sure you are not. I am buidling it along with a modern glassship so that I would like to work out a comparison based on OLDTIME WINNERS and MODERN high techs.( I will use R/C systems and building preference at that time and those stuff (Ancient model proportional rc systems)in good shape is hard to come by, but I am lucky to get all I wantd within this 2 years time. Relics are including a 1979 Simprop top model 8ch Contest SSM set in mint conditions and many Kraft 5-7 ch systems circa 78 to 83 just before Kraft was closed out.).
I am going opt for all possible flying surfaces except spoilers is being obseleted at primary maiden flights, hope it lives long to be mods.

Like to follow this section more frequently and I found more things I can't get from the ARTF, including the HIGH TECH MOULDIES( Goldies also $$).
I hope I could have at least one of them (cb4 and a moebius thermal egliders) completed before my next trip out....

Good luck to everyone working hard into his/her prjts . Cheers David

[mhodgson]

mhodgson

So what do you do, leave the foam inside the wing (between sheeting and ribs)?

erich

As said there is no foam inside the wing, its simply a using a 'mould' to press the skin onto the rib/spar structure.

To the others, I agree. I've never had wing sheeting pull off either in flight, whatever method I've used, and no I don't put gallons of glue on 'to make fillets' either.

I do it simply because it's a good idea (should any glue happen to squeeze out, make it work for you rather than just run down the ribs) and with using the foam blanks as moulds it is very easy to just flip it all over.

I've also used a variation on the lead shot idea and filled zip lock bags with dry sand. Not as heavy but works as well.

to each his own...

[erich]

Unpinned wing from board. Hey, it's sorta straight. That's gotta be a first. Added LE piece and planed and sanded to within a reasonable facsimile of an airfoil. Basically right center wing is done, and am moving on to left center section.

erich

[erich]

Have completed most of left center wing now. Just need to add LE, TE and top sheet. Both center sections will then be finished, and I can move on to the tips. Was a little easier to build, because it faces forward on build board.

erich

[erich]

Left and right, wing center sections, completed. While setting one wing on top of other, noticed a difference. The spoiler tubes were not in the same place on the two wings. Figured I goofed. But slowwwwly it dawned on me, it's for connecting to opposite ends of servo arm....duh. Good news is the two wings are very much alike. One weighs 6.1 oz. (right) other 5.95 oz. (left). Don't know if that's good or bad, but that's they way it glued up. I'll just use the heavier stock on the left wing tip, and just maybe it'll come out even. None of this is of any great consequence , just something my, little mind, can have fun playing with.

erich

[Gliderguy]

So, what is the big tube for that's in front of the spar? :confused:

[erich]

Gliderguy,

Shhh.....just between us, it's where I keep, test tubes, filled with....ahhh....brandy.

erich

[mhodgson]

I believe it's the balast tube.

[oracle_9]

It is the ballast tube, but adding brandy in a test tube is not a bad idea, come to think about it...hehe :) When you need less weight, you simply open up the test tube and "remove" some brandy. Heck, trimming you plane with the correct ballast weight can be more fun this way. And it never hurts to "double" check your correct ballast weight too.. oh man,...lol

[erich]

Ok...Ok...the plans do say it's for ballast, but hey who says you have to follow the plans all the time. Besides full size sailplanes use liquid for ballast, and when they don't want it anymore, they just dump it. Same thing I plan on doing, except won't be dumping it on the ground.

Now, to a less serious side. The instructions call for using 1/2" brass tubing cut to 3" or 4" length, filling them with lead. So now you got, easy to add, ballast. For using small amounts of ballast a wood dowel would take up the slack, along with a small piece of foam at the root ends.

erich

[erich]

Plans all laid down, covered with wax paper and waiting for wood. Just looking at the photo below, looks like two halves of a giant stabilizer. Looking over the plans, noticed that it is a very clean wing tip design. Nothing added except the absolute basics. Really like the simplicity of it.

erich

[erich]

Making some good progress. Pinned down basswood TE, after feathering it's TE and cutting to length. Added bottom LE sheeting and bottom spar caps, using Titebond. Cut and fitted all the lower rib caps. On the plans there appear to be no rib caps for the 3 outboard-most ribs. These ribs are the same as the others however. So there would be 1/16" gap where these ribs meet TE and LE sheet. This would make it difficult to adhere to the coating. So my solution was to make narrower rib caps for these last 3 ribs, to save weight and still allow monokote (or whatever) something to adhere to. Not sure if this is a mistake on the plans or what?

erich

[erich]

And now the ribs. Changed the shear webs somewhat. It calls for 1/16" shears on fore and aft sides of spar caps. I put them under spar caps. The first bay has the joiner shear with ply outer shears. On 2nd and 3rd bay I used 3/16" shears. Bay 4 has 1/8" and bays 5-8 got 1/16" shears. Bay 9, 10 have no shears. Whole thing is kinda of a shear mess. Oh boy....been around the CA to long. Used Titebond on shears and where ribs meet spruce spar cap. CA on rib to rib caps.

erich

[mhodgson]

Looking good. Nice piece of building, can't wait for the fuselage- always my favourite part of building. I think I'm going to have to get one.
A favour please though, could you shoot a close up of the TE structure? Looks fairly familiar but conformation would be nice.

[erich]

mhodgson,

Ok. Here you go. The TE (bottom) material is basswood, real nice wood to work with. Finer grained than spruce. Was able to, plane and sand, a fairly sharp edge on it. The top of the TE is balsa, which you can see in last photo. You can see in the pic I still need to sand down the balsa TE piece a little.

Can't wait for the fuselage myself, my favorite too.

erich

[mhodgson]

Thanks, it was what I expected. The last time I made a TE like that I sandwiched a strip of 1/2" glass tape in there to give a stronger and less warpy TE. Also sanded to a nice edge.
Then I went to cutting off the chamfered bit and using 1/8" Balsa with a 1/64" ply laminated to it instead. This again gave a tougher and sharper edge.

[erich]

Had thought about adding a small carbon strip along TE, but after sanding basswood, found it held a fine edge very well. So decided not to add the weight, when it really didn't seem to be needed. Did do the carbon strip thing (small 1/8" wide, carbon strip with epoxy), on a SkyBench Challenger, it works vey well (allows for an even sharper edge), but adds quite a bit of weight. On the Dodgson (Windsong, Camano, Pixy) planes of a few years ago, they used 1/64 ply between balsa sheeting. I built about 4 of Dodgson's planes. The edges I was able to produce, with this method, where always a litle wavy, especially on the 132" span Windsong. It may just have been the way, I did it, however. I used Titebond on the ply/balsa joint. It might have been better using epoxy. If getting a really sharp and clean exit is the main objective (disreguarding weight) , I personally believe the carbon/epoxy method is the way to go.

Have found the hardest part in modeling (almost anything) is knowing when to stop. Something can ALWAYS be made stronger, prettier, tougher, cleaner. And the trick is in knowing how much strength (etc) is needed for ones intended purposes, before the additions become overkill.

erich

[erich]

Before putting on, top spar cap, made sure all shear webs were proper height. Used spar cap to check for gaps. Glued in shavings from a razor plane to make up for low spots and a nail file to sand down high spots. Employed my, high tech, spar holder downers (3rd photo). Used Titebond for all joints here.

erich

[erich]

Top spar caps all glued up. Check out the fit and looks like no gaps between cap and webs. To me, this is when the wings look best, spar is done and ribs are still totally open to view. From here on the handiwork starts to get covered up. Next step top TE and then LE pieces.

erich

[erich]

Will be getting back to the building shortly. Had quite a bit of rain in NE so been out paddling the rivers. In the meantime, if anyone has some photos of a completed Scooter. Would love to see them posted here!

erich

[erich]

Finally making some progress. Glued on top TE balsa sheet, using titebond on basswood to balsa sheets, and thin CA, on top sheet to rib joints. Added false LE piece to tips, sanded to proper taper and glued in top LE sheeting. Used Titebond on spar and rib to sheet joint, and thin CA on sheet to false LE joint. Weighted down with lead shot and let sit a day or so. Afterwards add hard balsa LE piece and sanded to shape.

Next step, add the top rib, cap strips, and balsa tip blocks.

erich

[erich]

Been awhile getting back to Scooter project. Finished the wing tips. Glued up stabilator. Assembling the stab is straight forward. Sanding it is another matter.
The ribs are basically rectangles, so the ends need to be sanded quite a bit. The thing is you got to be real careful not to over-sand it. The end ribs are a little delicate. Builds up into a nice and light stab. Meant to take pics of the stab build process but it went together pretty fast so only ended up with some finished photos.


erich

[gliderlee]

Good job erich..

my glider

and me

[erich]

Mr. Lee

Beautiful. Looks like all wood including fuselage. What a pleasure to work in wood.

erich

[erich]

Framed up rudder. Using a bigger TE section (that wedge shaped stuff), for TE of rudder. This so's I can sand one side down somewhat to make TE se-metrical. also propped TE up 1/32 so ribs can be sanded even on both sides. Looks like a nice clean design, especially like the crossed braced ribs in bottom bay.

erich

[erich]

Sanded rudder and stabs to reasonable airfoil shapes. Added some curves and tips. Also finished outermost tips on wings. Plans call for a kinda square shaped look, at the wing and stab ends, prefer the more rounded look, so that's how I sanded them. The two bare stabs together weigh .83 oz. the rudder .28. Don't know for sure, but seems fairly light to me.

erich

[erich]

Built stab control horn housing. Kit came with 1/64 ply housing sides, with pre-drilled holes for horizontal stab control horn. Made alignment quite simple. Then added top of vertical stab, by pinning housing to plans and building rest of v. stab around it. Did some preliminary sanding. So am done with all flying structures. Next comes......ahhhh...the fuselage.

erich

[erich]

Finally getting to fuselage. The kit comes with preformed; forward fuselage, sides (ply) and rear (balsa). All that's needed is to glue them together using a 1/32 ply doubler for reinforcement. Just had to make sure front and rear were aligned (4' straight edge). On some planes it works better to build fuselage bottom first and work up. This one it seemed better to make each side, then join them. It's a pretty narrow fuselage, and this way I can add all the inner fittings (servo rails, formers, longerons) with much greater ease. Anyway at this point have, front and rear sides mated, and added longerons, used titebond throughout, this step.

erich

[erich]

Have added the front 4 formers (ply). Within the span of these formers the fuselage sides are parallel. Glued formers to one side making sure they're square to that side. Usually use epoxy for formers but decided to use titebond. Added support pieces for servo rails. A lot easier to do this now, rather then trying to shoehorn them in, after fuse is together. Nose cone is kinda unique. It's four pieces of basswood with the two middle pieces partially hollowed out, for nose ballast.

erich

[erich]

Glued up other side of fuselage. Also added the nose block. Nose block needed to be tapered toward front, to fit curvature of fuselage. While letting glue set up, checked with a small triangle to make sure left and right sides stayed perfectly parallel to each other. Used titebond here too.

erich

[erich]

Added tow-hook reinforcement piece (1/8" ply) between F2 and F3. Had actually fitted this piece before gluing sides together. Installed formers F5 - F8. Did this over the top view plan, to get location and alignment accurate. Used titebond on ply and thin CA on balsa formers to balsa side joints. Starting to look like a fuselage.

erich

[erich]

Glued on the front bottom sheeting (1/8 ply). Will add the rear (balsa) sheet later, after all control rods are in place. Used titebond for this. Also did some work on shaping the canopy.

erich

[erich]

Added servo rails. The kit comes with six rails pre-cut (they fit perfectly). Made up the rear hatch, needed so spoiler servo can be hooked up. The hatch hinges on the rear wing alignment pin, tube. So will have to hold off gluing in rear tube, till plane is covered.

erich

[oracle_9]

Looking good erich. Keep up the great work. I like that lean look of the narrow fuselage of the Scooter 3m.

[erich]

Thanks. Like the thin look also. Found you got really plan, the assembly steps, in advance (especially the linkeages) cause there just isn't any extra room.

Finished fitting hatch to fuselage. Did some more shaping on canopy. Have angled back of canopy and front of hatch, so closing canopy also holds hatch down. Will probably use, a small screw at rear and wood pin at front, to secure canopy to fuselage.

erich

[erich]

Using titebond added, basswood wing fairing blocks, to fuselage. Inserted wing rod and rear alignment pin while letting glue set up, to help alignment. Also glued in main wing brass tube. Bottom rear sheeting has been added also. Now able to sand bottom corners to give a more pleasing shape to fuselage.

erich

[erich]

Rear hatch has been hinged. With hatch closed and canopy in place hatch is locked down tight. Finished shaping and sanding canopy, also sanded out a small depression near front to allow clearance for battery. Only thing left to do in hatch canopy area is add hold-down screw for hatch. Usually use rubber bands for this, but just found no room to anchor them with the narrow fuselage. Besides the block for the hold down screw will allow me to reinforce the main wing joiner tube.

erich

[erich]

Glued in the vertical stabilizer. Horizontal control rod had to be connected before gluing in, as it's impossible to do later. Plugged in wings during drying process to make sure of alignment. Added top deck piece, making sure fuselage had no twist in it. Did some sanding on tail, giving the Vstabs LE a pleasing rounded look.

erich

[erich]

Installed the three servos. Used standard size servos, which makes for an extremely tight fit. Connected up control linkages for rudder, and elevator. Using carbon push rods. Thought they might save some weight, but they weigh almost the same as plastic rods. At control surface end, just CA'd (thin) a threaded metal clevis onto the rod. That's what it said to do in the push rod kit instructions. Was sure, thin CA, would not hold metal to carbon. So did a test piece. Clamped clevis in vise and used a big pair of pliers, then pulled as hard as I could. It held. What the....! So CA'd a threaded coupler on servo end, added clevis, and am in business.

erich

[erich]

Glued in, stab pivot pin tube, using 30 min epoxy. While waiting for it to dry was certain I had inadvertently glued tube to H-stab horn, which is suppose to pivot on this tube. But got lucky and horn moved fine. Added wing alignment pin tubes. Spoiler tubes installed and working of spoilers checked out. Had to reinforce ribs where spoiler tubes makes bend. Was then, finally, able to finish sheeting, and cap stripping top portion of center, wing sections.

erich

[erich]

Did the final fairing in, of fuselage-wing joint. Added thin strips of balsa where needed and then sanded down to get smooth transition from wing to fuselage. Also did some sanding of top center panels. Next step, connect center panels and wing tips.

erich

[erich]

Joined wing tips to center panels. This kit uses two ply joiners on either side of spar caps and a solid balsa piece between caps. Also a small ply joiner is fitted to rear of LE piece. Glued LE joiner and forward ply joiner to main panel. Then used them to line up the tip panel. Added balsa shear and rear ply joiner, followed by the 2 rear ribs. Added rib caps and some sheeting, and ended up with a reasonable facsimile of a wing. Now just got to do the same to other wing.

erich

[erich]

Joined second wing. This one went a lot quicker. Now that plane is basically built, had to plug everything together, just to see. Comparing this plane to the Challenger, it looks as if you could fit Scooter fuselage inside Challenger's.

Pretty much up to, putting on covering, always takes me forever to figure what colors to choose. May try a two tone, transparent, plus white. Tried to use some 22 year old monokote, found it doesn't shrink very well. Well off to the store.

erich

[erich]

Couldn't decide between using transparent blue, or yellow. So went with some of both. Not sure if I like the result, will be able to see better how it looks when both wings are done and plugged in to fuselage. Got a wing and a stab done.

erich

[Frunobulax]

Erich,

What color scheme do you have in mind for the fuse?
Just my personal opinion, of course, but with all that sheeted surface on the wings covered in white the blue and yellow look a bit "overwhelmed", especially on top. You did such a gorgeous job on your Challenger I look forward to seeing the final result.

[erich]

Looks that way to me too. That's why I did a little more blue on the bottom than top. For fuselage, probably all white with a little blue in tail and a black or maybe blue, canopy. Have always stayed with white or yellow for fuselages. They both show up well. And I probably believe fuselages should be white. Although my paragon has a green fuselage. Also had a GL with a maroon fuselage. The Paragon and GL where the first two planes I built, so hadn't come to my senses yet. You know, young, foolish and wild. Mostly though, it's that, I got an excess of yellow and white monokote.

Thanks for the interest.

erich