rcjim000

Yes it is...which is why I have several unfinished kits. I can't seem to get past the sanding/covering phase...

wfmnut

Mike - You are right - I am having a blast building this kit. I have assembled a few ARFs, but there is more gratification when you see the completed assembly emerge over the plans. That feeling could change as this build runs into week #3, then #4...Jim and I were IM'ing earlier today and I was asking what our next build-off was going to be - a GreatPlanesUltra Sport or Super Sportster - ormaybeSig 1/5 Cub. Perhaps we should focus on finishing these first as like Jim, I haveseveral airplane projects that need to be finished.

Jim - You are moving along pretty fast (and I am sure it helps seeing what the completed parts look like before you start.... I couldn't resist). I guess you will have the tail feathers sheeted sometime tomorrow.

MinnFlyer

My Feedback: (4)

Ultra Sport. You will be amazed at the thought that went into the engineering of the kit - and then when you fly it, you'll be spoiled for life!

rcjim000

The first picture shows the fin with one side sheeted and scrap balsa added for the hinge points. I did the same thing for the stab, but I forgot to take a picture. The other two pictures show the tail section with the sheeted fin and stab and the rudder/elevator with the scrap balsa added for the hinges

TonyBuilder

My Feedback: (11)

wfmnut

Looking good Jim! Was the use of scrap pieces for the hinge points in your plan or instructions (notin mine)or is that just something you addedbased onyour building experience? I wish now I had thought ofthat but it is too late for the fin and stab unless I cut a little of the sheeting away and retro fit which is probablynot worth the trouble. I made a little progress on the wing of my Chippy but also spent some time working on the Skylark to have hercloser to being readyfor the next warm day we see.

On the Chippy, I got the landing gear block epoxied in, as well as CA'ed in both upper spars. I also CA'ed the TEsheeting to the wing panel andhave cut and sized the LE sheeting but did not glue it. The instructionssuggest wetting the sheeting to help it conform to the shape of the airfoil. I was thinking of dampening a ragto wipe over the top of the sheeting. My concern is that when I placethe weight bags on the dampened sheet to hold it in place while the CA cures, it might actually cause the sheeting to sag between the ribs and hold that shapetoo (as it dries). I need to review the "Build a Trainer"video again andsee how Mike and Ken went about it. I would like to avoid having to dampen the sheeting.

Not nearly as much progress to showincomparisonto you and my lack of building experience is becoming apparent. Perhaps you should have given me a month instead of a week to start before you...

wfmnut

TB -

I think you have settled the question of flaps for me as I have been flip-flopping back and forth as to whether I wouldaddflapsto this plane or not. I have read that this plane really doesn't need them and initially thought I would build it without them. When I came across the aileron strip set in the LHS, I bought them anywayto provide me theoption of using them when I get to that point in the build. You make a good point of how the extra aileron length could make the plane more aerobatic and fun to fly. I had already decided at the beginning of the build to replace the plastic wing tips with carved balsa tips, as well as replacing the two plastic wing fairings with balsa. I think it will be well worththe extra effortin the end.

DougB1

My Feedback: (11)

You guys are driving me nuts ! How can you build a plane piece by piece instead of flying ( even though it is 25degrees out) I have a hard time just putting in servos and engines let alone building a WHOLE PLANE !! Just wanted to give you a hard time Loren but wanted to let you know I am watching the thread ( GO LOREN ) This is going to be fun to see who gets done first, hey Loren can I test fly it for you ???? LOL

Doug

ho2zoo

My Feedback: (5)

Hey, I wanted to test fly it! [8D]

Thomas

dragonov3

My Feedback: (3)

Here is the one I built for my friend. Im the one flying it in the video. Has an OS .61fx, Black and yellow Monokote, Hi tech radio, balsa wingtips and no flaps.
http://www.youtube.com/watch?v=9PFnD2gpMi4

DVI

I have built two of the Goldberg Super Chipmunks, I'll try and post pictures of the last one I built. They are good flying airplanes and the the last one I balanced it tail heavy so that it would do very nice tumble maneuvers, and flat spins. The flat spins took some time to get out of so you could not let it to close to the ground before recovery.
[img][/img]

wfmnut

Sweet-lookingChippys thereguys!!!

I am surprised Jim hasn't posted his progressthis evening. I know he was working on his build today. Not much "physical"progress on my end. I lifted the assembly off the steel board and cut my spars at the root of the wing (something I should have done before I glued in the ribs). I taped the LE sheeting to help "conform"it to the ribs (while I decide how I will attach it). Istartedlaying outthe sheeting between the LE and TE sheeting. I won't trim it until the LE sheeting has been glued into place. I also spent some time cutting and fitting a cardboard template as a potential servo hatch for the aileron servo that will be placed out in the wing. I am wondering if I caninduce a slight bow into some 1/8" ply to match thecontour of the ribs - although that mght make it more difficult to attach the servo.

As this is my first build, I am struggling a bit with procedures -likegluing down this big LE sheet as it is alot of area to hold down while the glue sets.I haveconsidered usingmedium CA and quickly working my way from the root to the tip (and even getting my wife tohelp hold the panel to shape), or thick CA and apply kicker to the bottom side of the sheeting. Another possible approach is to use wood glue and pin the sheeting to each rib as I go. Since I couldn't decide today, I will think about this tomorrow and come to some sort of a decision by tomorrow evening. Not sure I will have any building time tomorrow evening as my wife hasother plans for us. I guess Jim gets another day to gain ground on me.

In the photo you will notice that I did get the wing supports assembled. Ireallyhopethat once I get past this first wing,the build will start moving alongagain.

rcjim000

I did not get much done today. I drilled a couple a holes on the rudder for the hinge points, but figured out that one of them was not centered. So, I glued in a dowel rod to fill the hole and drilled another hole.

Loren: No, the instructions did not mention adding balsa scraps. It is something I picked up from reading several threads here on RCU. Your attempt to slow me down today did not work...

DVI and dragonov3: Nice looking planes!

crick1983

Good work!!! I have been interested in this plane for a while. You have encouraged me to give building a try!!!!!  Here goes nothing...

chymas

My Feedback: (1)

I glued the TE of the LE sheeting to the spar using thin CA. I then glued the rest with medium CA and held in place with green masking tape (it holds better than the blue but can still be removed).

rcjim000

crick1983: Cool! Please post pictures of your progress.

wfmnut

I am surprised Jim hasn't posted this evening. Either hetook the night off or he is still in the basement working away...

I got started late this evening - arriving home around 9:45PM. First matter of business was to inventory my Tower Hobbiesorder that arrived today:white monokote, 1/8" robart hinges, 22"sanding barwith 180- and 220-grit sand paper, and some #11 blades. I also purchased a Great Planes armament kit for a GP F4-Phantom kit I will build (one day) which they were clearancing out. I will have to look closely at the robart hinges and how many "barbs"will be in the wood on my tail feathers. At first glance, I am not liking what I am seeing andmight end up having to cut the sheeting on the fin and stab and glue in some hinge "backers" like Jim did. It would be easier to do it now then to realize I should have done after a couple of flights. I didn't look real long at the situation this evening because I didn't want to be contemplatingit while laying in bedtonight. Care to wager what willbe going throughmy mindthis evening while trying to fall asleep...

With my wife's help, we got the LE sheeting glued on this evening. I went with the medium CA and no kicker. Looks like we came out pretty well too. I didn't get a good seal between rib #2 and the sheeting, but that could work to my advantage as it will be easy to get tobeingit is on the root end of the wing, and it may end up helping me to fit the dihedral brace as well. Needless to say, I am not too worried about it right now and it really seemed to go pretty well.

Tomorrow night my clubwill be starting our weekly Tuesday-night "Wings for Kids RC Air Show" planning meetings for theannual fund-raiser eventwe hold each year over the first weekend of June. Last year, we raised just shy of $15,000that was donated toKosair Charities. It's a two-day show and we generally have pilots from Team Futaba, the likes of Mike Barbee and John Boyko (Scale Master's aircraft), as well as several other "notable" andlocalpilots flying in the show. This year, Futaba is holding it's International Extreme Flight Championships (XFC) the same weekend, so we will need to cultivate some new pilots for this year'sshow.

Anyhow, here is a photo of the progress on the wing tonight. I am hoping to finish up sheeting this side of the wing tomorrow evening.

wfmnut

OK - here is where sharing this build via thread will hopefully pay off....

I laid out my idea for installing the robart hinge points. Yes - I was thinking about it last night even though I was hoping I wouldn't. I can still add the hinge point doubler s like Jim did to the control surfarces (rudder and elevator halves). My concern is that the hinge point gets progressively larger near the actual pin of the hinge. IfI notch the control surface so the hinge sits back in the control-surfacepiece a bit, I am hoping I will havemore "uniform bite"in the stab and fin on the "holders" of the actual hinge. This should permit me to keep the holein the fin or stab more uniform and (I think) will provide better holding power.

I am hoping someone with some "real" building experience will jump in and say "yeah" or "nay". Any thoughts?

MinnFlyer

My Feedback: (4)

You will find that after the holes are drilled, you will have to enlarge the openings of each hole - not necessesarily cut a relief. This is why you want the entire "holding area" to be encased in wood (or at least most of it)

wfmnut

Minn,

I see what you are driving at in your illustration. Due to my inexperience, I may have caused an issue for myself in that the hinge point will not be fully encased in wood in the fin or stab..

When I constrcuted the fin and stab per the plans, I did not add any additional wood to the frame of these parts for the hinge point to fully extend into (Depicted by "A"). Since I have already sheeted the fin and stab structures I can not add any additional wood (backing) for the hinge point (lower arrow from "A") to sink into unless I cut out and remove some of the sheeting.

"C" represents the frame of the rudderor elevator pieces where I can still get toand add additional wood (depicted by "B") so the hinge point will have more wood to bite into (on the movable control surface). I figured that if I was to notchthe leading edge of the rudder or elevatros (depicted by the lowerarrow of "C")and position the hinge point slightly back into the movable portion of the control surface, it would provide less gap between the fin and rudder (as well as the stab and elevator halves) and the hole that would get drilled into the TEof the finor stab(depicted by "A") would not have to be enlarged to accept the wider portion of the hinge point;hopefully yielding a tighter fit on the barbs of the hinge point in part "A".

I am afraid that if I enlarge the opening of the hole at point "D" for the hinge point to fit in the TE of the fin or stab (like in your illustration), only one barb of the hinge point will actually be glued into the wood - the rest of the barbs will be in the dead space between the sheeting of the fin/stab (again depicted by the lower arrow of "A").

Would you recommend I cut out some of the sheeting and glue some scraps into the back of thefin and stab to make the hinge point installation stronger? PerhapsI amworrying about this more then I need to be as the original plans didn't call for this modification; however,they were not using the Robart hinges either.

The photo is a true 1:1representation of the dimensional wood that was used toconstruct the structures anddepicts howthe actual hinge point will be fitting into these pieces.

Another option that came to mind this morningwould be to look at thesmaller Robart hinge points (for 1/2a scale) and simplyuse1-3 moreper mounting surface. I haven't looked at the dimensions of the smaller hingesyet but plan to do sothis evening after the meetingas another option. I just don't want to lose a control surface back there during flight because there wasn't enough contact between the hinge point(s) and the wood on the fin or stab.

MinnFlyer

My Feedback: (4)

Ok, picture 1 is what you have now. If you cut a nice, square section out of the sheeting, you can add the blocks. Then, using some of the same balsa, add more blocks unter the sheeting so you have a bed for the new patch to sit on. This will keep the sheeting flush with the rest.

A little filler and some sanding and you'll never see it.

chymas

My Feedback: (1)

wfmnut

If you take a 1/4 brass or aluminum tube, sharpen the end of it. Find a drill bit that just fits the ID and cut about 1" off the back end and then glue it in the opposite end of your sharpened tube.

Drill 1/4 holes where your hinges will go in your stabilizers and control surfaces - step drill with normal drill bits.

Then take your tube that you built and drill into the end grain on a balsa block - drill about 1" to 1-1/4" into your block but don't drill all the way through or you will have a tough time getting your dowel out of your drill tube. You can make several of these at once, after you get done tube drilling your block simply cut the block at the 1" mark and your dowels will fall right out.

Glue your balsa dowels in place and then drill for hinges.

DougB1

My Feedback: (11)

Loren, this is why I fly and don't build. LOL
Doug

wfmnut

Tonight, I finished sheeting the underside of my left wing panel. Itshouldn't be toolongbefore I will bestartingthe right wing panel. That will hopefully go a little faster now that I have an idea of how it goes together. My next big concernwill behow the two wing halves will fit together?

I also built a 1:1 scale, partialmodel of my fin and rudder assembly from scraps to address my concernsregarding the fact that I didn't put any additional blocking material in the fin or stab (to accept the Robart hinges). As neither the rudder or the elevator halves are sheeted, it will be no problem adding backing material to these parts; however, beingboth the fin andstab are now sheeted, if I want to add backing material, I will have to cut the sheeting off one side and patch as Minn addressed earlier. (Thankyou!)One thing that has bothered me is that the hinges supplied with the kit didn't require blocking material, norwould CA hinges.

One thing Ithought aboutthe other night was off-setting the hinge point by placing it deeper into the control surface) and appliedthis approach in my mock-up this evening. I think this solution will keep me from having to cut open the sheeting on my fin and stab to add the blcking material. My new concern will be how to ensure I don't get epoxy in the actual hinge point while inserting the hinge into the control surface. I plan to dip the hinge point into vaseline as suggested, but I am unsure how well it will work - perhaps I will need to make my notches just a bit larger. I do really like the fact that rounding over the LE of the control surface and recessing the hinge point makes the assembly look muchmore realistic then if I was to usethe sanding tools that came with the kit to create an "angled" LE. With thr rounded LE, the control surface still seems to have plenty of range of motion. Iam a little surprised thatthe drill jig provided with the hinges seems to make an over-sized hole for the hinge points.Perhaps to allow a little slop for better alignment of the pieces?

In the photos below, the orange portions are pieces of sheetingI glued onto the balsa (used to frame the fin) to accurately represent the fin assembly. It was nice to see thatmypartial model served it's purpose andactually worked as a proof of concept.

wfmnut

Trimmed the sheeting on the left wing panel and sanded to about 1/16 of the frame with the exception of thesheeting at the root of the wing. I will let that go until I get closer to fitting the two wing panels together.

Talking to Jim today I learned he is working on hinging his tail feathers now. We were talking about using the Robart drilljig and this evening I confirmed our suspicionsfrom our discussion earlier today. I thought it strange last night that the 1/8" drill bit I was using fit very sloppy in the jig. In fact, I used thejig with a 3/16" drill bit to make the notches in the mock-up of the control surface after I had run the 1/8"bit for the hinge pins. This is my first experience with Robart hinges. I purchased a 1/8" combo pack, which is supposed to come with 50 1/8" hinges, a 1/8"drill jig, and as a bonus, an instructional pamphlet on installing the Robart hinges. I had also decided to purchase an additional Robart drilljig (set containing a 1/8"and 3"16" collets) to have a sparejig on hand (one for each size). If you saw my benches you would understand. This evening, I confirmed they sent a drilljig with a 3/16" collet inthe combokit containing the 1/8" hinges. I guess I should have looked at the package containing the second drill jig kit last night when I questioned the fit of the jig. At the time, I was just figuringthe collet was over-sized to allow the hole to accept thewider portion of the hinge point (at the "neck" of the hinge pin) and to allow a little "slop"for alignment of the surfaces (if needed).Another valuable lesson learnedfrom this build; if in doubt - stop andreason it out. I am just glad I did this on the mockup and not the actual tail feathers.

Finally, I started laying out theright wing panel.I have the triplers thatI made for rib #4glued and drying tonight.The doublers for ribs #3 and #5 were glued when I constructed the pair for the left wing. This TE piece has a nasty bend to itso Idecided to"align" itwith the magnets and let it set there overnight before I start gluing ribs (perhaps tomorrow evening).I want to be sure I have it nicely aligned before I start gluing. It looked good downstairs this evening but I still see a little bending in the photo - which will probably sand out.

RCKen - the two magnetsat eachend of the spar are a pair I pulled out of a disk drive (four per drive). I simply can't get over how powerful they are. I made the mistake (twice) of havingone attach directly to the steel plate below (while constructing the other wing) and the only way I could liftit off was with a pair of pliers. I will be pulling some more of these magnets from the old disk drives before I haul them off to be recycled. THANKS for the tip!!! I will try to remember to bring afew to Toledo this year in case I run into you.A magnet-board builder can always make useof a couple more magnets.