samparfitt

My Feedback: (43)

That should be the blue can.
The label says for doors and windows which indicates that it's the low expansion so it doesn't bow out the windows/doors which would make them inoperable.

glazier808

My Feedback: (1)

Looks great Sam, will it fit in the trailer?

I wanted to ask, sorry if I missed it, but are you using spring hinges on the retract doors? I see how you're closing them, but I can only assume they are spring loaded.

Thanks

Casey

samparfitt

My Feedback: (43)

Casey,
No spring hinges.
The springs to open the doors are quite robust so when the gear goes down, the shear size of the spring straightens itself, thus forcing the doors open.
Initially, I wasn't sure if this set up would work, but I'm very pleased with it's simplicity, yet reliability (at least, so far on ground testing!).
I'm a big believer in using air cylinders on doors but, in this case, there just wasn't room for them (at least, I couldn't find it).

glazier808

My Feedback: (1)

I like it!

Thanks!

Casey

samparfitt

My Feedback: (43)

Assembly (cont)

I had to make a double Y extension: one end to battery and power safe receiver and other end to charging jack and voltwatch.
Both batteries (6000 ma total) wrapped and put into the nose.
The last two extensions to be made are for the throttle/choke servos, which were mounted on the removable fire wall and screwed to the fuse.
Sullivan's ball connector with locking sleeve (S591) are used to easily connect the servos to the engine.

samparfitt

My Feedback: (43)

Assembly (cont)

Tank assembly:
I use viton tubing for the clunk area as it's methanol resistant. The brass tubing is bent using the K&S tubing benders. Dubro barbs are CA'ed to each brass end and fuel line clips are used to hold the fuel line on the tubing. A piece of brass tubing between the clunk and outlet to keep the tubing from 'horse shoeing'. I'm using a 40 oz dubro tank and I replaced the philips head screw on the cap with a hex head screw.
I use a 'two outlet' method and put a T fitting between the tank and carb that is used to fill the tank.
The 'overflow' tubing wraps around the tank, externally, to reduce spillage when doing loops, etc.

Engine:
The DA-85's engine ignition system is secured inside the fuse on a tray in front of the batteries.
The two receiver batteries and ignition (all 3000ma, 5 volts) are behind a removable ply panel.
The fire wall was secured to the fuse. The overflow tubing in the picture had to be rerouted through the same hole as the spark plug wire as it would be right over the muffler.

Rudder/tail gear:
Dubro's 4-40 pull-pull system was used on the rudder and also the tail gear. The system is nice as the wire is coated and shrink tubing is provided to help reduce any snags. I used some ball sockets on the gear side to help reduce the chance of kinks. The rudder and tail wheel are on the same HS-645 servo.

samparfitt

My Feedback: (43)

Assembly (cont)

Engine:
The engine was mounted and fuel lines, ignition and servos were connected.

Fuse:
The wing was attached to the fuse and the back side windows were installed using #1X3/16" wood screws.
The cowls (top/bottom) were attached using some of the button head screws. I re-tapped all the holes before inserting the screws to insure no binding, thus stripping out the T (blind) nut.
The prop and spinner were assembled.

The last few things to do (besides a maiden!) is balance and engine test.
I'm happy with the color combination as I think it will be easy to see in the air.

samparfitt

My Feedback: (43)

CG

4 inches back.
Only needs about 4 lbs of lead with the gear up: I'll 'take it'!

butlern

My Feedback: (15)

Good luck with the maiden flight, Sam!

Looking forward to soon reading about the early and excellent flights!

Noah

Scott Prossen

She looks great Sam. Good luck with the maiden. Don't be be shy with the flaps buddy!!

Scott

samparfitt

My Feedback: (43)

Thanks Noah and Scott,
I'll be using full flaps which is about 45 degrees.
Presently, I plan on the maiden flight on Thursday.

===================
Fine tuning:

Canopy:
The ply lip on the front of the moving canopy was, sometimes, catching the front canopy so I sanded a beveled edge on the ply as well as on the front canopy.
After adding the back side windows, the screws on the sliding canopy was snagging it so I had to grind them down and then I added some box tape over the area.
I had to drill/tap some holes and screw in some 4X40 button head screws along the back brass guide rails to prevent the canopy from going back less about an 1/8" as this is where the ball links can come off the front guide rails (for removal and maintenance). This keeps the canopy from, possibly, popping off in the open position yet I can easily remove the canopy by removing the two screws.

CG:
As you can see in the side picture, I'm moving the lead weight from the bottom of the fuse where the 45 degree angle starts to over the engine. This moves the weight 12" forward which saves me a lot of 'dead' weight. I cut some aluminum L angle, cut it to fit over the DA-85 mount and drilled two holes that match the top engine mount holes. I then screwed some 1/8" thick ply to the L angle, built a little box from 1/4" thick ply, epoxied and screwed it all together, made a 'screw on' lid and painted it.

samparfitt

My Feedback: (43)

fine tuning (cont)

Overflow tube:
I drilled a hole in the bottom of the fuse and ran the overflow tube using hanger 9 (han116) fuel filler w/T and overflow fitting. The kit gives a nice flush finish for the over flow. I attached the overflow fitting to a piece of 1X2" ply so I can easily install/maintain it as the inside area is too small to tighten the locking nut. The overflow is just inside the bottom cowl flaps.

Engine test:
Before installing the cowling/spinner, I tested the DA-85 engine using a Mejzlik 3-blade 24X10 getting 1800/6500 rpm's: exactly what I wanted and absolutely no needles to adjust. The engine started easily with about 10 flips with the ignition on and choke on and about 4 to start her after taking the choke off (not bad for a new engine).

Engine test video:
http://www.youtube.com/watch?v=zktnG...ature=youtu.be

Cowls/spinner install:
I then re-tapped all the holes and put all the 4X40 button head screws into the cowls. Two #6X32's hold the front halves of the cowls, together.
Lots of screws on the cowls and 15 on the spinner.
There were about 3 blind nuts that came off while re-tapping the holes: no big deal as I have more than enough screws holding the cowls onto the fuse.

CG and UP gear check:
Last, I checked the CG; a little nose heavy, which is what I like. One thing nice about rear rotating gear is: if the plane is tail heavy, just put the gear down.
I left the gear in the UP position for an hour to insure the air pressure, also holds in the UP position.

Peter_OZ

My Feedback: (1)

lead: why not use flat strips of lead in the cowl lip. I put about 3 lbs around the lip of my seafury in that manner. Means a lot less dead weight is needed. I used silicon sealant to fix it in place. Great planes have lead strips that can be contoured to fit in nicely.

I hate dead weight! [:@]

samparfitt

My Feedback: (43)

Peter_oz,
I've been unable to locate lead strips in quantity at a reasonable cost: I get the buckshot from a local firing range (25 lbs for about 40 bucks).
I agree with you about dead weight as I put all my batteries as far forward as possible, but I'm not comfortable with lead on the cowl of large planes as the cowl requires a very sturdy mount to the fuse and I usually don't have a lot of room around the engine. My normal solution is a tray mounted over the engine. There are many solutions to problems, and I'm sure you're comfortable with your set up and it works well for you.

Peter_OZ

My Feedback: (1)

41 lb seafury, about 4 pound of lead in the chin. Has 4 screws holding cowl on, 2 top, 2 bottom. Never had a problem with it. I'd have had to add about 6 - 8 lbs if I put it over the engine.

Each to their own though!

good luck with the maiden.
Cheers
Peter

pforty

Hey Sam,
She looks and sounds great. Good luck with the maiden, can't wait to see the video. I'm still plugging away on mine.

Bruce

samparfitt

My Feedback: (43)

Thanks, Bruce.
Did you make yours a 3 piece wing, and if so, how did you do yours (show pics).

pforty

Sam,
I followed your design for the most part. I did a few things differently and will try to show them. You are doing a great job on this thread, I hope I don't detract from it.

I used the same approach for the center section, except I placed my C bar in the center of the spar and drilled and tapped for 2 4x40 bolts to hold the outer panels tight. Later I added the landing gear strap on the bottom like you to ensure the panels don't move. I also ran the top and bottom double spar out to W-7.

I stayed with the plans and used the 1/2" dowel to hold the leading edge of the wing, and kept the opening in the center of the wing where I will mount my valve for the retracts.

I used Sierra landing gear and didn't have to hack up the bottom spar. It also allowed me to use the W3a and W4a ribs without modification, as well as the spar doubler WR.

I also mounted the flap and aileron servos to the hatch cover so just the servo arm sticks out. Your flap servos embedded in the wing and pushing the flaps with no external control horns is much cleaner, but I stuck with my old ways on this one.

samparfitt

My Feedback: (43)

Bruce,
Thanks for the pictures. It looks like you did a great job on the construction. Darrell's gear are nice looking.
The weather keeps getting worse as the week progresses, so I'm going to the field, today, as winds are 4 MPH, sunny and mid 60's.

pforty

Sam,
I hope everything goes great for you today.

I was surprised that you had to add nose weight. That DA-85 and Ziroli spinner are a heavy combination on that long nose. The last P-40 I built required weight in the tail and I was anticipating even more with this one.

samparfitt

My Feedback: (43)

Bruce,
Two elevator servos in the tail, full cockpit that has casting parts, a Dragon full pilot which are not made lite, functioning canopy, 4 flap servos, panel access behind the cockpit. Not much lead needed though, probably about 3 lbs.
I'm guessing just under 40 lbs. As I've mentioned before, I like heavy warbirds as I think they fly more realistically.
Also, I error on 'nose heavy' side when doing the CG balance (better sluggish than porpoising).
The plans say 4" (which is what I used): the wing is 21"; so at 25%, it seems like it should be 5-5 1/4".

Going out around 1 PM so for now, besides charging up the batteries, I'm cleaning up the basement (from the winters work) and the detached shop and then will get back to finishing the B-26 marauder. I like the aluminum on my Z P-47 so I'll be doing the same to the B-26.

butlern

My Feedback: (15)

Good luck today, Sam!

ROGER RUSSELL

My Feedback: (12)

Good Luck Sam:
On My TF P40 I had to add 13oz to the tail of my P40 to get CG back to the recommeneded 5.5".
I used a heavier engine then designed for. (G62 vs DLE 55)

Hope to maiden mine this weekend IF I can get myself back into the basement.
I don't seem to have the spare time as you, or dedication.......lol
Only need a couple hours.........lol

samparfitt

My Feedback: (43)

Roger,
Your TF is farther back than my Ziroli: Think I'll call them, this morning.

samparfitt

My Feedback: (43)

I just talked to Ziroli and 4-4 1/4" back with the gear DOWN.
That probably translates to 5-5 1/2" with the gear UP.