Dirty Birdy Kit help (Bluejay)
 

I have just started building my dirty birdy kit and have run into a snag. I think I am missing some pieces from the kit or I don't know what I am looking for. If anyone else has this kit I am hoping you can help me out.

Step 3, last para of instructions it wants me to draw a center line on the TOP BLOCK CROSS BRACES. It says the pieces are factory cut to size but I cannot find these peices anywhere. From the plans it looks like they might just be 1/4"x3/8" sticks but I want to be sure before I continue.

Can someone check this out on their airplane and let me know what these pieces look like and maybe their dimensions so I can cut them myself if need be?

Thanks.

RE: Dirty Birdy Kit help (Bluejay)
 

Ah, yes, I hunted through the entire kit several times for these pieces too. They are not precut, it's just sticks.

If you haven't already been through it, look at my thread on the DB http://tinyurl.com/36p6yf . You may want to drill the wing dowel holes later in the construction as I detail in the thread. Makes setting the incidence easier.

Dave

RE: Dirty Birdy Kit help (Bluejay)
 

tlgibson97,

I am building the Bluejay Dirty Birdy and have found that Bluejay for the most part just copied Bridi's original building instructions. They need to make some changes to the instructions since they have modified their kit from the Bridi DB.

glockguy

RE: Dirty Birdy Kit help (Bluejay)
 

tlgibson97, I don't know how much it would help, but I have the two-part construction article from RCM. It seems to go into a good amount of detail from what I remember. Let me know if you want it.

David

RE: Dirty Birdy Kit help (Bluejay)
 

thanks dbacque, I have read through your thread before buying the kit and I just read it through again for good measure. I guess I am just a little leary about cutting on the wrong part. Its not really that big a deal but if I don't have the stick in stock that I need it just means a trip to the hobby shop. I usually end up getting more than I intend to.

Rainedave, I don't know if it will help either but it sure wouldnt hurt. I would like to read it. Every little bit helps.

This kit is a new experience for me. I have built a top flite kit and I learned a few "what not to do's". I am just trying to get into SPA since a few member keep prodding me to do so. This year I would rather be flying at Hotlanta rather than working at Hotlanta.

Thanks for the help. I'm sure I will have more questions later.

RE: Dirty Birdy Kit help (Bluejay)
 

Like I said, I hunted through every part in the kit numerous times looking for that part. Then in a moment of obsession, I read through the plans several times looking for anything that used that stick. Only then did I finally decide to cut it. Kind of silly if you saw my closet full of balsa!

Yes, it was intimidating to be on step 3 and already face such a problem. But after that, everything went smoothly.

Oh, in the Bluejay kit, the slots for stab and fin are not precut. You need to transfer the stab location to the part and cut it yourself. I did it before assembly by stacking the 2 sides together with a little double stick tape and cutting on a band saw. Turned out perfect. On the fin, I found it easier to cut the slot after the fuse top was glued on. Don't do any rounding on the fuse yet! Just plane the fuse top down to match the sides, good and square. Then you can measure to accurately mark the slot in the center of the fuse top and cut out with an X-acto and straight edge. Then you can use your razor plane to round the fuse out. Of course, it's much easier to do all the rounding before the stab and fin are glued in. But don't round the bottom of the fuse near the wing saddle or you'll have problems with the wing fillets.

Dave

RE: Dirty Birdy Kit help (Bluejay)
 

Question for dbacque, what brand and size fuel tank did you outfit your DB with.
I'm pretty good with building these models when detailed plans and pics are provided.
As been said before, the plans and instructions can get you baffled.
By the way you said the incidence was incorrect, what is the correct measurement?

Thanks
George

RE: Dirty Birdy Kit help (Bluejay)
 

George,

Sorry, I don't have a clue what size or brand tank I have in my DB. Been too long since I've seen the tank!

When I spoke with Lynn at Bluejay about the wing incidence, he told me that the figure printed on the plans was correct. It was something like 1/32" or 1/64" positive incidence. The instructions are going to have you adjust the wing to the proper incidence. The thing that I found was that I needed to lower the leading edge of the wing to reach proper adjustment. The problem was that the wing was already doweled, so I couldn't change it. I mounted the wing, measured how far off it was, plugged the holes and redrilled them. Then taped Monokote backing sheet to the wing put epoxy with microballoons on the saddle and bolted the wing on, checking incidence again. It gave a nice saddle and perfect incidence.

This is the method the plans give, I just had to adjust the front of the saddle, not the back. And I thought it easier to move the dowel holes than recarve the whole wing saddle.

Take a look at my thread referenced above, it gives detailed measurements.

Dave

RE: Dirty Birdy Kit help (Bluejay)
 

One tank that will fit is the Hayes 12oz Slimline. It has beveled top edges and was designed to fit in narrow, rounded fuselages:

http://www3.towerhobbies.com/cgi-bin...?&I=LXK835&P=7

The 16oz one might fit, but wouldn't leave any room for foam padding.

David

RE: Dirty Birdy Kit help (Bluejay)
 

I'm building one now, albeit slowly, and yes , the instructions are vague in some areas. The good news is that Lynn will clarify matters over the phone or by e-mail. I've built a gazillion models since the early sixties - from a Berkeley Bulpup to a 35% Carden and I must admit that the instructions have me scratching my head at times, despite having the plans and measuring. I'm using a OS55ax and 10 ounce Dubro tank. Good Luck !

RE: Dirty Birdy Kit help (Bluejay)
 

Thanks all for the input,
I built a DB back in the early 80's when it was a fiberglass fuse and foam core wings. I loved that plane. now after being out of the hobby for over 20 years I have to have another one.
I'll try and take pics and post them as it goes together.

Thanks
George

RE: Dirty Birdy Kit help (Bluejay)
 

I'm also in the process of building a DB from BlueJay. I installed the Hayes Slimline 12oz as described above, I agree that the 16oz would probably fit but it would be very tight. I decided to buy the foam core for the wing from Dynamic Balsa rather than build up the wing that came with the kit. If I manage to build this kit true and it flies well, I'll probably build up the wing later and install retracts. I'm also planning to us an OS55AX so I'm hoping this configuration will help control the weight.

RE: Dirty Birdy Kit help (Bluejay)
 

Oh man, the directions for this kit are really giving me a hard time. I have run into numerous questions/problems while working on this thing. I decided to stop working on the fuselage until I have a motor to put into it. I have a os 61fx on its way to go in. I started to mock it up some with a 91fx I have since they are the same size. I found that if I have the firewall in its correct location then the engine sticks out about 1/4" too far. Is it acceptable to move the firewall back some to accomodate it or is there something that would cause a problem later?

I am stuck a little installing the tri-stock in the fuel tank area. Where the directions say to put it doesnt match where they are on the plans, plus the dimensions differ from the plans and the directions. Not sure what to do thee quite yet.

I stopped on the fuselage there and went to the horiz stab and elevator. That went together without any problems and it got rid of some parts out of the box. I also did the vert stab and rudder. Pretty simple there just a bit of sanding. I think they are both looking good.

Now I am working on the first wing panel. I marked centerlines on all the ribs, LE, and TE. I have glued all but rib 1 to the bottom spar per the directions and I have glued the TE to all ribs. Now I am in the process of leveling the ribs to sand the TE flush with them. I am cutting 1 block per rib to place under the TE. I'm using a self leveling lazer to ensure they are all level. I went ahead an put in the top spar (without glue) so I can clamp the entire assembly down at the spar to ensure it remains flat to the table.

I noticed the ribs have slots on the LE and TE. I couldnt fine anywhere in the directions what they are used for. I have a lot of 1/16 stock like what was used in the Horiz stab. I was thinking they might be used for the ribs also but wasnt sure. Can someone help me out?

Another Q about the fuselage assembly. when glueing the sides to the top block, in the engine area, should the sides curve to follow the plans or should they stay square? I can't tell by the directions if they stay square and are sanded to shape or not.

A few things I am trying:

I am taking dbacque's idea and putting a battery compartment in the tail.

I have also installed the elevator servo in the tail. I am using a single control horn for both elevators. I saned each elevator individually then using sandpaper wrapped around the 3/8 dowel I sanded a groove in the elevators. I then put the elevators against a straight edge ane epoxied the dowel in with weight holding the elevator surfaces aligned. It turned out well but I am going to epoxy some 1/8" dowel throught the 3/8 dowel into the elevators for extra support.

I think I will used pinned hinges for all surfaces.

I am using 4-40 rods everywhere with ball links on the servos and soldered clevises on the horns.

I will have a servo in in each wing for insurance.

I have JR DS821 digital seervos for all control surfaces.


Speak up if any of you think any of this is not a good setup, inadequate, overkill, etc.

Maybe tonight I can take some pics and post them so you can see my progress.

Thanks

RE: Dirty Birdy Kit help (Bluejay)
 

tlgibson,

I tried an OS .61 FX but found that it didn't fit the stock plane because of the rear needle valve. It needed a little extra length. I had another engine on hand that fit, so I just used that one. I don't see where moving the firewall by 1/4" would be any problem but I'm no expert. A .91 will be a lot of engine in that plane! My ancient Magnum .65 is plenty. How does the weight compare between the .61 and the .91? The .61 should be plenty. If the .91 is heavier, beware.

The triangle stock in the nose is just the standard affair. Glue the sides together and fill every corner with triangle stock. Do pull the sides in when building the nose. Look at the nose ring, that will give you an idea of where the sides need to be. I couldn't get things pulled in quite enough and had to add some wood inside so I could carve a nice flowing curve to meet the spinner. Remember, you're going to carve away most of the nose. Make sure you've got enough meat inside. When I carved it I did open up a couple of holes in the corners. I just filled what I could with wood and the rest with epoxy with microballoons.

The slots in the ribs are for using a wing jig. If no jig, you can ignore the slots. What I did was to run a balsa strip through the slots and then put blocks under the strip to jig the assembly to level. It worked well for me but it sounds like you've already got your jig set up.

Dave

RE: Dirty Birdy Kit help (Bluejay)
 

I wasn't planning to use the 91 as the motor. The case sizes are the same so I was just using it to see how things would fit. I didnt have a problem with the needle valve with it. I have the rear cover plate bolts all the way against the engine mount and it was still too long. If I put the 91 in it I bet it would sure scream, but then it wouldnt be SPA legal. Weight wise, with the stock muffler the 91 is only .7oz heavier. They are the same without mufflers.

RE: Dirty Birdy Kit help (Bluejay)
 

Also, doea anyone have any ideas for a good 2-3 color covering scheme? Looking for something high visibilty and orientation friendly.

RE: Dirty Birdy Kit help (Bluejay)
 

The original wing and stabilizer design featured a slotted leading and trailing edge. A piece of 1/16 strip was inserted into the slot in the leading edge, then each rib was slipped onto the strip until it butted up against the leading edge. The whole thing could be assembled and straightened on the plan before a drop of glue was applied. Not sure why the leading and trailing edges are no longer slotted. It was very effective.:eek:

RE: Dirty Birdy Kit help (Bluejay)
 

Here's what it looks like.

David

RE: Dirty Birdy Kit help (Bluejay)
 

check your mail box

RE: Dirty Birdy Kit help (Bluejay)
 

Oh, the frustration. Is it something I am doing wrong or is there not enough sheeting it the kit for the wings. I have the 4 LE and 4 TE sheeting pieces but the 4 top center and 4 bottom center dont cover the space needed. Help.

RE: Dirty Birdy Kit help (Bluejay)
 

I don't remember being short on sheeting in my kit. But then again I've got a huge box of balsa in the closet and would have just grabbed another sheet.

It does seem that many kits I've built through the years were very tight on sheeting. Cut one angle wrong or use one sheet in the wrong place and you don't have enough.

I'd just pick up a sheet or two at the local hobby shop and press on.

Dave

RE: Dirty Birdy Kit help (Bluejay)
 

ok, after staring at the plans for a few hours, reading directions over and over again I finally realized that this isnt a fully sheeted wing. Once I figured out the function of the rib caps I realized how it was supposed to be. So I am not short on sheeting, it was just some confusion by me. I started to use some sheeting I had in stock but I just didnt feel like it was correct so I just studied it harder until it clicked.

What is the best method of doing the other wing panel. I built the first on top of the plans. Just looking for the most accurate way to do it. Plus I dont want to end up with 2 left wings.

RE: Dirty Birdy Kit help (Bluejay)
 

Here's a photo of the cap strips. Build the second wing over the same drawing on the plans; the wing is symmetrical. Just remember to install the gear blocks on the opposite side, i.e., upside-down. The old method is to rub the plans with cooking oil and simply turn them over (the oil makes the paper translucent and the ink shows through). This ruins the plans, though.[:o] Better yet, I can email you a reverse image of the wing half that you can print out if you want.

David

RE: Dirty Birdy Kit help (Bluejay)
 

Email sent

RE: Dirty Birdy Kit help (Bluejay)
 

Thinking out loud, I wonder how much weight penalty there would be in sheeting the entire wing? It would then allow one to fiberglass and paint it to match the fuse....