butlern

My Feedback: (15)

Sam, you're a madman!!!

How about I drop off two or three kits to your house this December and you can get them all finished and ready for me to fly by May? Sounds good?

Keep it going, buddy.

Looking great, and like almost everyone else who frequents this site, I'm watching with interest and enthusiasm!

Noah

samparfitt

My Feedback: (43)

Noah,
Your F7F looks great.
Nice work.

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Horizontal stab (cont)

I figure that the stab is going to get a lot of stress so I wanted to insure the stab doesn't fold in the center.
I cut some aircraft ply to connect the two halves of the stab, plus some balsa sheeting for the center section that goes between the elevators.
With dihedral in the stab, I can't just sheet the entire center area for strength, so I made two V shaped plys that were epoxied along the TE and main spar.
The main spar on each stab half, besides the dihedral, also are not parallel to each other so some triangular pieces of balsa was cut so the V ply could be epoxied to the spar.
The sheeting for the filler section was also added.

Fuse (cont)
Another 4" wide sheet was added to the left bottom side.
Due to a compound curve, I cut the sheet, about in half, to get it to fit.
One piece was first glued on and about a 3/8"X 20" triangular piece was cut off the top piece so it would fit the compound curve and be aligned with the bottom piece of balsa.

pic 65-74 will be posted after the web site fixes their problems.
( last night, I could even get into their web site so I was hoping that, this morning, they were fixing their problems, but, apparently, not!)

samparfitt

My Feedback: (43)

Fuse (cont)

Top half (cont)

I applied a full sheet, minus trimming to about 1/2 along the nose to the right lower side.
A narrower piece would have worked better along the compound curve on the nose as I had to use some really strong clamps (orange tipped ones), along with paint sticks to hold the sheeting to the stringers (and even then, I needed a couple of heavy weights on the fuse as that side lifted about a 1/16" along the curved section of the nose by the crutch stringer).
I also added a sheet to the top, center to the where the stab is located.
A last piece of about 12" long and trimmed to fit along the lower left side at the back of the fuse.

I have about a hundred pins holding the crutch stringer to the building table.
After sheeting is completed, I hoping that I can use a putty knife to lift the top half of fuse off the table as 1) the plastic pins heads pull off pretty easily or/and 2) the soft hollow core door (only about a 1/16" thick sheeting) will lift the pins and allow the fuse to separate from the table.

uploading errors on pictures; will post them when the web site is fixed.

pic 75-78.

samparfitt

My Feedback: (43)

Tail feathers (cont)

Elevator

The center is 3/32" contest grade balsa (as well as all parts of the elevator) with the ribs 'straight' cut from spare balsa sheeting.
Two sheets were taped together to get identical halves (the edges were first sanding straight on an L angle that has sandpaper glued to it).
The center sheeting was extended to the balsa block ends so the blocks can be glued directly to the sheeting.

The ribs were drawn on the sheeting and then center points were drawn on the sheeting so 'lightning' holes can be drilled out using a forstner bit.
The 3/8"X1/2" LE was then constructed from a 1/4"X1/2" and 1/8"X1/2" balsa sticks.

1/64"X1/4" ply was CA'ed to the TE of the elevator to 1) make it perfectly straight, 2) resist warping and 3) allow a fine edge to be sanded and 4) resist 'hanger rash'.

The ribs were then cut and CA'ed to the sheeting and, finally, the trim tab was constructed.

Only the top half was constructed so the center sheeting could be pinned/weighted down to insure a perfectly flat elevator.

pic 79-86.

pictures will be posted when RCU fixed their problems.

samparfitt

My Feedback: (43)

Fuse (cont)

Planking/sheeting (cont)

The right lower back side was sheeted next: cut in half as on the left side.
The 'filler' sheets are needed now on the left side.
I cut/fit one on the back left side and then on the left front side.

Engine choice:
I'm going with the DA-50's.
They aren't much larger than the G-38's.
I forgot that the G-38's are old and don't have choke butterflies: I like to have servos operate my chokes so that 'sealed it' for me.
The plans show a scale 20.5" prop and I think the DA's will probably swing an 18X8 4 blade so that would be cool.
Looks like Beila makes a 4-blade prop:
http://www.troybuiltmodels.com/items/BP1810-4BY.html

the web says 50-60 size engine for a 20 incher:
http://www.troybuiltmodels.com/items/BP2010-4BY.html

pic 87-93

pictures will be uploaded when RCU fixes their problems.

samparfitt

My Feedback: (43)

Fuse (cont)

Planking (cont)
The nose and right back side were sheeted.
Only a few small areas to do before the top is done.

Tail feathers (cont)

Elevators (cont)
The ribs were cut/CA'ed to the bottom of the elevators.

pic 94-99

no pics posted until RCU fixes uploading problems.

samparfitt

My Feedback: (43)

Fuse (cont)

Planking (cont)
I used a putty knife to start removing the top half of the fuse from the table but I found it easier just to start lifting with my fingers. About half the pins came out and the other half, the pin heads pulled off.
I took the fuse out to the detached shop and sanded the surface using 100 grit paper wrapped around a paint stick. Before I sanding off the 'tick' marks for the top wing hatch, I used a razor saw and cut the balsa sheeting between the two formers.
On it;'s back, it looks like a big boat!

pic 100-106

NOTE: pictures will be uploaded when RCU fixes their web site.

zipnz1

My Feedback: (2)

Wise choice on the da50's sam. The 38's would do the job and its hard to pass on old reliable but the 50's are powerhouses for their weight. You probably should stick with no less than a 10" pitch prop on that plane to keep the airplane speed in the comfortable range.
This is one of my favorite bombers i am looking forward to the finished build.

mike

invertmast

My Feedback: (23)

+1 with the choice on the DA50's. I'm still debating on either a pair of those or going electric and putting a pair of scale size and shape SOLO props on mine.

darren763

My Feedback: (117)

You guys better put brakes on them if you are using 50 cc engines on a 120 size plane.....Does it have enough room for the Props? Fuel tanks area big enough for a 24 oz tank?
I would go with the DLE 30, I have a friend with an Ultra Sick Lite turning a 19 x 8 has unlimited vertical at half throttle. A couple years ago you suggested to Zach and I to use the G-38's. But bigger is always better....


Darren

samparfitt

My Feedback: (43)

RCU finally fixed their web site (at least for me!).
(they still have a problem when 'clicking' to the next picture as it often, randomly, goes to a previous picture, or skips pictures, or none at all. The only way I can look at all the pictures is to close each one and then open the next).

All pictures have been loaded going back to post # 23.

No new updates since last Thursday since I've been busy on my daughter's house, doing yard work, moving planes to their hanger for winter storage, moving all my crap from the detached shop to the basement and prepping planes for going to Mac Hodges Rally of the Eagles and FT Monster flyin.
I'm leaving Thursday and will be taking my Ziroli P-47, SBD and comparf F4U.

Well, I did do one thing:
While cleaning up the detached shop, I cut some 3/8" square and 1/4" square and 1/8"X1/4" hardwood stringers. I've been 'eye balling' the wing plans and the main spar is 3/8" square and the TE stringers are 1/4" square. I didn't have any hardwood stringers in those sizes so I 'ripped' them on my table saw using straight grain maple and cherry. I had some small left over pieces so I cut some 1/8"X1/4" stringers that will be good for strengthening the doors and the area around the doors.

samparfitt

My Feedback: (43)

Wing (cont)

Using my P-61 for reference for when to use aircraft ply, I re-cut the main spar and all light ply ribs with aircraft ply. I also lengthened the main spar to extend into the outer wings by one more rib W-11) for extra support (W-11 upgraded to aircraft ply). All spars are also hardwood that bracket the main spar and the two TE spars.
The main spar will be sheer webbed to form a box main spar. The TE will also be sheer webbed.
The ribs making up the nacelles are also aircraft ply.
I want the center wing to be 'flex free' and able to withstand two engines and the main gear.
I moved the main wing joiner to the center wing so now the outer wings have the bar support sticking out the ends of the wing. I'm not sure why this is set up the opposite of what is 'normal'. I'm figuring; without a bar sticking out of the center wing, less space taken up in transport and not likely to bend than when they are part of the outer wings.
One half of the center wing is 'dry fitted'.
The 'tools of the trade' for cutting new ribs/spars was just a good scroll saw and an belt table sander.
Initially, I was trying to decide how to extend the wing another 3" on each side.
It was getting complicated and a lot of work: I noticed that just adding the extra 3" to the end was the easiest solution, especially, since the taper is not that much for 3" of additional wing. I'll just add a rib or two for the extension.

invertmast

My Feedback: (23)

Looks good Samuel. I had intended to do the same making some of the lite-ply parts out of aircraft ply. I also want to try and replace the blade spar setup with a pair of Tubes and sockets, so I'm definitely looking forward to seeing if there is enough room for that.

Exhaust3

I wanna see more of the train layout!! Holy train cars Batman!!

samparfitt

My Feedback: (43)

Thomas,
The aircraft ply is 6 ply versus 3 for the light ply.
The 3 ply in the kit is pretty stiff but I wanted to insure my gear doesn't come out when I bounce on a landing or go into rough grass (I've had some 3 ply where hard balsa is stronger). I've had some rough landings with my P-61 and there are no stress cracks anywhere on the plane plus the gear has not ripped out: For me, it's worth the extra time and a few bucks as a 40-50 lb plane gets a lot of stress.
After 'dry fitting' half of the wing, I also was thinking that maybe I should have put a tube in there: but then I'm too lazy to do all the checking to see if the gear will operate correctly with that set up.

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exhaust3:
If you look at some of my other build threads, you'll see the layout in the background in a lot of the pictures. IE: SBD, Hellcat, P-61 and F9F build threads probably have pictures of the layout.

samparfitt

My Feedback: (43)

OK, here's a few pictures.

invertmast

My Feedback: (23)

I agree, the extra work and expense for 6 ply is worth it in the long run, i'll be doing the same. I'm also thinking of having the wing center section permanently attached to the fuselage so that i can have scale operational bomb doors..

The gear is my biggest concern with using a pair of wing tubes. Hopefully they will fit, as i really do not like the use of blade spars.

samparfitt

My Feedback: (43)

Thomas,
This is my first use of the 'bar' system.
I've also want operational doors so I've been thinking about 'sheer webbing' the formers between the wing and bomb bay so I can make the wing removable.
When I built the top half of the fuse, I used the lite ply top half formers, but with the bottom half, I'll be replacing any lite ply with aircraft ply that supports gear mounts and around the wing support area.
I added extra ply to the next former back on the booms on my P-61 as I was worried about them 'snapping off' (as I've heard that the P-38 has done).

ram3500-RCU

My Feedback: (221)

This is so cool Sam. Brings back my HO days. All boxed up and tucked away in storage for my grand kids, I guess.

samparfitt

My Feedback: (43)

Gary,
thanks,
also have Lionel.

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Thomas,
I forgot that I had a Yellow AT-6 with bar wing supports and I had no trouble with it.
As mentioned, I made the main spar out to the next rib. I'll also be making the bar longer, screw it to the spar and epoxy ply around it so it should keep the outer wings rigid.
Looking at the side view of the nacelle, it does look like you could easily add a tube support, if you want to go that route.

darren763

My Feedback: (117)

The Sig wing Joiner is very similar to Byrons wing joiners and most of theirs are that style. Keep up the good work building your B-26.

Darren

samparfitt

My Feedback: (43)

Thomas,

The bar connector is at the top of the wing; when flying, the stress will cause the bottom of the outer wing to flex outward so I'm going to copy the ziroli C-45 technique and epoxy a ply/metal tab to the outer wing and then just screw it to the inner wing when at the 'field'.

invertmast

My Feedback: (23)

With that view, it looks like a 1 1/2 or 2" wing tube could be used withing interfering with the landing gear.

samparfitt

My Feedback: (43)

Wings (cont)

The bar length on the kit supplied wing joiner kit is too short since I'm extending the main ply spar another rib on the outer wing, so I bought some 1/8X1" aluminum bar stock. It needs to be 7/8" wide so I set up the table saw using a carbide blade to cut the bar stock. A piece of wood was clamped to the table fence and some feather boards to keep the stock tight against the fence.
Unlike the usual set up of adjusting the blade only an 1/8" above the stock, with the aluminum, I need the blade about 3" above the table so it won't chatter when cutting the aluminum (the wood clamped to the fence will keep my fingers from getting near the blade). A face shield is needed as the metal 'saw dust' flies everywhere.

ACE hardware has a nice selection of #6 screws.
I got some #6 flat head with tapered sides to hold the aluminum joiner channel to the spar (By the box, they are pretty cheap). After drilling a hole for the screw, I used a larger bit to form a tapered side so the screw will be flush to the surface of the aluminum joiner channel and will allow the bar stock to slide into it.

I may use two kits to get a more stout wing joint.

DENTO

SUBSCRIBED
Go for it Sam if you ever want to come down to aussie for a winter I will put you up and you can build one for me
REGARDS
JOHN