jrm82266

A 1/6th scale Waco YMF-3 was returned to me 10 years after I built the plane. It has only flown twice (not pretty). The first flight consisted of a severe oscillating tail and the second flight munched the right wing. I have since lost the plans and was wondering if anyone can give me the upper wing incidence and the CG as measured from the upper and lower wing leading edges. I read one of the posts that said the stab shoud be +2 degrees incidence. I am not sure if I built this in and I think this may be why the plane only flew twice, lol. If anyone can provide me with this info that would be great. Also please let me know if the stab 2 degrees positive is LE up or down. Some consider positive incidence on a stab as the LE down since it causes the nose to rise. Thanks for the help.

Garthwood

I just came across this thread. I'm at the moment building the Pica waco YMF - 3 1/6th scale. If you are still interested to have your question answered, please let me know. The reason I say this is because this thread is about three months old.

regards
Garthwood.

jrm82266

Garthwood,

I still need the infomation. Thanks for the reply. Most people see a post this old and do not respond. Thanks again

Garthwood

re.waco

(1) According to the plans The top wing incidence is O degs. I measured the leading spar and the trailing spar in relation to the crutch and I don't see any difference.

(2) The plans show the BALANCE POINT of the UPPER WING as measured from the front of the wing's LEADING EDGE to the rear spar and just infront of that to be 4.5 inches. So you have to measure from the leading edge of the top wing and back 4.5 ins. and you arrive just infront of the trailing spar.

Ref. Stab.
(3)The instructions on the manual says that: If you have an incidence meter, the incidence should be 1-1/2 deg (38mm deg) POSITIVE relative to the CRUTCH. If you don't have a meter, the front of the STABILIZER should be 1/8th. highter than the REAR when measured from the CRUTCH.

I hope this should give you some starting point. I'm still at the building stage of the fuselage at the moment. I have never flown a bi-plane or even build one, so this is my first bi-plane. I have built other planes before.

Garthwood

TomCrump

Gentlemen

I grabbed this information off a thread on RCU awhile back. The info was purported to come directly from Pica.

Top Wing pos 1 to 2 degrees.
Bottom wing 0
Stab pos 1 1/2 degrees

Because of the wing shape, the incidence should be checked at rib W6. You'll see why when you put your meter on the wing.

Garthwood

Thanks Tom..................for the additional information regarding the top and bottom wings incidence. I'll add this information to the manual.
Garthwood

Xrod

My Feedback: (2)

I second the information given you by Tom. If one measures the incidence off the plan side view, you will be using the center section of the top wing which has a sort of ducks a-- profile. Check the wings a distance out from the center section. The stab platform on mine gave me too much positive incidence before I owned an incidence meter......results in down elevator trim. Too much trouble to move it now. Heres some pics of mine...good luck with your Waco.
Steve

Garthwood

Erod:
Nice job you did with the Waco. Thanks for the advice.

Garthwood

Garthwood

XROD:
Can you explain your switches in the middle picture please, and how you went about it ?. Thanks, Nice job.

Garthwood

Garthwood

Hi Tom:

Have a question: Re. checking stab incidence. I'm at that point of the Stab............to glue F-15 STAB SEAT to the top of F13A,F-14T and the tail end joiner, is there anything I have to watch out for ?. Once the platform is built, how's the stab's incidence corrected at this point ?. The fuse should be set at level position. I have a Robarts Meter. Can you explain the rest please ?.

The stab seat over the top of the tail end joiner. The stab should be glued perfectly flat on F-15 STAB SEAT, once the stab is checked for squarness it is ready to be glued in.................Am I right ?.

Regards
Garthwood

TomCrump

Once the fuselage is level, I set the stab on the platform and pinned it down securely. I then checked the incidence. Mine was a little off. I had to put shims under the stab, until it was properly adjusted.

Garthwood

Hi Tom:
Thanks for your reply.

How is your covering coming along ?.

I'm ahead of myself with this question, did you use the Wing alignment jig on the plans and if you did was it is helpful ?.

I'm going to ask Santa for some 21st. century fabric. How many rolls do you think this bi-plane takes ?.


Garthwood.

TomCrump

Hi Charles

I've finished covering and I'm in the process of hinging the control surfaces. I have the styrene gas tank glued on and the corrigations on the bottom wing ailerons. I'll finish hinging this weekend, and should spray the primer at that time.

I didn't use the alignment jig. I have three incidence meters, and used them all.

I think you'll need four rolls of covering. I can't say what I used because I had two opened 15 foot rolls of Super Coverite. I never looked to see how much was on either roll before I started.

I thought covering the fuselage was a bear!!! The turtle deck poses some interesting problems, at least for me, it did.

Garthwood

Hi Tom:

So you're installing a gas engine in the Waco ?. Before you started the covering did you smoothen the fuselage stringers' sharp edges ?.

I am attaching a picture of the Waco progress................I have roughly checked the stab incidence and it is at + 1.0 degs. when the crutch is level (O degs.) I just need to add another + .5 degs. I still need to glue in the tail-wheel block. I hope the rest will go smooth. Covering is another task, and have to keep cool.

Regards
Gathwood

TomCrump

Hi Charles

I'm installing an OS 91 Surpass 4 stroke in the WACO.

I just dusted the longerons with some 220 grit sandpaper to know off the rough edges.

I didn't like the tailwheel block supplied. I made on from 1/4 hard ply. I used the PICA hardware, though.

TomCrump

Charles

I hope yu can see in the picture, why I didn't smooth the longerons. In the full size WACO that I have access to, you can see them protruding slightly through the covering.

Take a look at the wing, also. I'm trying to get the same effect.

Xrod

My Feedback: (2)

Garthwood, sorry it's been a while since I checked this forum. I decided that I would be building the scale hatch, and since with my engine, a TT .91 fs, I would be using remote glow, that I would hide all my switches in the hatch. The hatch door uses aileron hinges and a magnet with metal plate to keep it closed. I installed mounting rails for the switch plate on the bulkheads. The switch plate holds the remote glow, switches, charge receptacles and LED power on indicator lights for my redundant battery setup. If anyone is interested, I can take it apart and take some pics of the installation. My Waco is laid up right now for repairs. I cartwheeled it down the runway on a bad landing, and it feels like the spar on the upper wing let loose of the dihedral braces. I will have to do surgery from the underside to see. Good luck with your planes!
Steve

Garthwood

Hi Xrod:
Sorry to hear about the Waco mishap, but it happens. It happened to my Funtana last summer. But it was a good excuse to reinforce the landing gear and fire-wall. The Funtana S 40 is built light and those areas that I mentioned are quite weak. On the maiden flight I lost one wheel, the wheel shaft came off (a batch of wheel shafts with some kits got on the market). I managed to land it safely without any damage. Later I read on RC Universe that the shaft should be soldered, a lot of flyers were having the same problem.

Thanks for your offer, I for one will be very happy to see "How to pictures" of your installation in the hatch. Looking forward to see what you did.............thanks.

Good luck with your repairs, and she'll fly like non other but a WACo.

Garthwood

Garthwood

Tom................you must be very lucky to see the real thing. I see what you mean. Also the aileron covers are quite pronounced. That plane must be a beauty. I could imagine you sitting in the cockpit. Now I know why you like the WACo.

I used their tail wheel block (not impressed with it) but I reinforced it from the inside, I glued a 1/4 ply from the inside. I'm using a Sullivan Tail wheel bracket/#S861. The outside block is easier to carve out, I'm installing also two threaded brass inserts that take the same size of screw supplied with the wheel bracket. I'll attach the soft or hard spring to the rudder.

Xrod is taking some pictures of the hatch installation, that should be very interesting. I like the way he did his.

Garthwood

TomCrump

Charles, The owner flys this WACO all over Northern Michigan. It's a frequent sight at full scale flyins.

Garthwood

Hi Tom.......Thanks for the Waco pictures, that is a beauty. It must be a popular item at the shows.

Before everybody takes off for the Christmas holidays, just wanted to wish all the guys on this thread "A very Merry Christmas and A Bright New Year 2005". Do not drink and drive if you're driving to visit your families, it's not worth it. Arrive safe at your destination and enjoy your friends and families. I will be checking on this thread just the same, and continue on the Waco.

Charles.

TomCrump

Charles

Santa brought me an early present, a digital camera. I'm still learnig how to use it, but I have a few pics of my WACO in primer.

Garthwood

Hi Tom:
What can I say about your Waco but..........WOW ! It's really really nice Tom. I did'nt understand when you said your Waco is in primer.
What sort of digital camera did you get ?. By the way I got my CG Ultimate ARF from santa and it's a really nice bipe. The included hardware looks pretty decent.

In regard to the Waco, I'm at that stage where I have to attach the stabilizer, but I was waiting for my second Robart meter, which I got also for Christmas. I have completed the attachements of the ribbed plastic on the ailerons. My stabilizer reads + 1 deg. so I'll increase that plus another half/plus deg. The sanding of the cowl blocks are done. The interesting part is going to be the alignment of the wings. Did you come across any problems ?. I've decided earlier to have a servo in each of the bottom wings, and that's going to be a bit of a job.

Will send you some pics the next time.

Good luck with your digital camera..................you probably have to read a two inch manual. I have the Nikon 70D.

Garthwood

Garthwood

Tom:
Have you decided what flight pack and size of engine you're putting in ?.

I was thinking of putting in Futaba S3001 servos and a Saito FA100 4/S. A friend of mine suggested Futaba's S9001 all the servos.
He says they're much smoother and better servos. But they're also almost double the price of the S3001. This is one of those pretty planes that one thinks twice before flying it for fear of getting it crashed. But one has to take chances and risks otherwise the hobby is not interesting. Life itself is a big risk.

Charles/Garthwood.

TomCrump

Hi Charles

Since my last post, I've sprayed the color coat . Tonight I'm going to work on the cowl.

My camera is a Fugi FinePix S3100. I'm only scratching the surface with it, but it seems fairel easy to use.