DaleCS

Sorry to be away - a bit stalled. Switched back to cockpit, for now and was struggling a bit with the seat belt harness - perhaps overcomplicating it by trying to stich nylon straps by hand. Decided to look over some full-scale and RC seat belt strap examples to see there were ideas on how to simplify, yet still have the belts look good. Then, discovered that the harness kit I had purchased was of the wrong design - British! Now, the Brits did have belt latch mechanism that was simpler, faster to get out of - but not fitting for a US Navy fighter.

So, gave up my struggle - found a 1/5 scale Navy example from IFlyTailies.com said "Good enough!" I'll include some pics once I've got the seat installed.

Continuing to review cockpits, and waiting for aileron hinges, decided I would add some details not included in the cockpit kit. Decided to go ahead with recreating the head/shoulder armor plate and the mounting bracket for the headrest. The armor plate is made from 0.08" styrene sheet. The headrest mount, from 0.25" brass stock. Will use 4-40 socket head bolts - 3 to mount the armor plate, 2 to mount the brass bracket to the styrene.


Looking forward to getting this painted and mounted.

DaleCS

Head/shoulder armor plate, headrest with headrest mounting bar, in place.
Seat belt harness from IFlyTailies.

Now that I have this sorted and know how I'm going to attach the seat belts, will go ahead and paint, install the rest of the seat hardware.

DaleCS

Remainder of seat components painted - will let paint set overnight. I really like the shade of green used here - basically, a simple olive drab. Looks really good against the interior green used in the rest of the cockpit, giving the impression that the seat came out of another bird as part of a repair. Since there was no standard for interior green, variation was common. I have a piece of hardwood dowel that will be placed under the seat - screwed to the floor pan, glued to the seat - this will support the weight of a pilot figure.

Worried about the top seat post mounting brackets remaining attached to the rear cockpit wall. I've got them pinned and plan to use a vinyl sealant to glue to the wall, as recommended by Dynamic Balsa. The sealant I plan to use is very robust - but there's not much contact area. Expect Dynamic Balsa's recommendation is fine - they've been doing this for many years. Just if it fails, the rework will be a pain - won't have the open sides which make current work much easier. Options? Pull the pins out and run a screw through the back wall into hole currently occupied by the pins.

Used a few bits from the British seat belt kit from Dynamic Balsa - painting them silver, seen in the first picture. I have 'em, might as well use 'em and these bits are generic - anchor points and belt adjusters.

Shoulder straps of seatbelt harness mounted - simply attached with a couple pan head screws and left a bit loose. Had the seat and pilot temporarily installed in order to find appropriate points to put screws.

DaleCS

Headrest mounted, shoulder and seat straps mounted, couple details on back panel painted and seat assembly in position, though not permanent. Will hold off making it permanent until further into final assembly of cockpit and plane. Found the anchor points for the lap belt that came with the IFlyTailies harness - will swap them in as they have a finer finish.



This is reference material used for choosing the two different shades of zinc chromate/interior green, from F6F Hellcat in detail and scale, Bert Kinzey.

DaleCS

Outboard flaps are done. Used construction technique taken from wings. Front is a D-box with shear webbing on top/bottom spars. Cap strips on top and bottom of ribs. For the top sheeting, used two layers of 1/16" balsa sheet, forming a laminate. These flaps are very stiff.

Looking forward to finishing the aileron mounts, finish sanding and then covering the these outer control surface in Solartex.

DaleCS

Chad's aileron bits arrived late last week, while I was in Nashville. Visited Stones River Battlefield, Sly's Hill, had some Nashville 'hot chicken,' heard some good country music and the Nashville Symphony - my wife has a childhood friend that plays for the symphony. Also visited Leipers Fork - nice little village in the hills that has some large RC events, but none were in progress last weekend. Maybe next time.

Gluing up the the 'yoke' (u-side) of the hinge arrangement. Chad had a pilot hole put in and a 0.050" Allen-key fits well enough to serve as an alignment pin during assembly. Will use a #50 drill and 2-56 tap on the u-side. The other, single bit (tang?), I'll start with a #43 drill (clearance fit) - if too tight, will use #41 drill.

I like these new ailerons hinges better - nothing wrong with the Tamjet hinges, but these replicate the Hellcat's better - the single tang extending back from the trailing edge will allow the clearance slot in the aileron to be 1/3 the size required of the Tamjet hinges - again, more in line with the full-scale Hellcat.

BTW - what does everyone think of changes on how pictures are managed here? Tried putting pictures within the text and pictures came in huge. Resized them with some difficulty. After saving post, the resizing was thrown out. So, removed the pics. As they are available at end of post as attachments, guess that this is the new way going forward?. And the editing window is only an inch (2.54 cm) high. Ugh!

DaleCS

Manufacturing background gave me an idea for faster processing. By running the Allen-key through 6 sets of hinges, can get one aileron set done at a time, and, this methods ensures better, squarer alignment of the pivot points. Tamjet hinges shown for comparison. The stationary part, to the left, is the portion that the aileron must be slotted to rotate around. May be able to see from this comparison the slot width difference needed between the two solutions. Will become clearer once these are mounted. Had started with the Tamjet hinges, so I'll be able to do a comparison picture.

The #50 drill and 2-56 tap worked well on the 'u' shaped part. #43 drill for through hole on 'tang' was sufficient - hinge swings smoothly, no slop.

DaleCS

One of the new ailerons installed (bottom), showing comparison with original (top, black). The new hinge requires a clearance slot in the aileron much closer to scale. Need a trip to LHS - out of 2-56 pan-heads, so using a control rod on the new hinge.

DaleCS

Chad's hinges, installed on ailerons. Build slowed by family events.

The ailerons are turning out to be my most complicated subassembly, so far. Still need to install sheer webs, cut/install ply square for control horn mount, mount control horn, install lead weight within leading edge (anti-flutter), top sheet and top cap strips, shape trailing edge and complete trim tab. Times two. And, still need to mount to wing.

PLANE JIM

My Feedback: (109)

My Byron is getting close for the maiden-your work is outstanding

DaleCS

Looks great, Jim. You'll enjoy that plane, I'm sure - still miss my Byron.

DaleCS

Making aileron progress. Sheer webs are in, counterweights in, control horns in, and one aileron forward top-sheet in place. Starting to look like they are close to completion...finally! The forward top-sheeting, I'm doing in two layers to avoid splits. Also, though the counterweights are epoxied in place, I glued a wood hold down over the top of them - just in case they loosen up, I don't want them flopping around, moving backward, ruining their purpose for being there. And if they do come loose and my hold down keeps them in place, I may not have to tear them open....belt and suspenders.

Bob Paris

My Feedback: (13)

Hay DaleCS,
I have been watching your F6F build and I love your work. The Hellcat never has received her due...and you are doing good...really good. Keep it up...and I love your pictures.
Soft Landings Always,
Bobby

DaleCS

Bob - thank you so much for your following and kind words. Was in Maui several years ago - honeymoon - 11 days, 4 islands - just in case we didn't make it back, saw as much as we could. Hope to make it back there for our 30th anniversary. Almost heaven on Earth - if the snow skiing were better, would be perfection! Tried looking up RC clubs on Maui - if you're at 2701 Mokulele Highway, that's one nice site.

I believe the Hellcat's lack of notoriety is one of the main reasons why I like it so much - good looking, if not distinctive, just a workhorse that got the job done extremely well - it's specs and stats speak volumes.

Top sheeting is done on both ailerons. I'll probably will not post for awhile - next steps involve top stripping the ailerons and then completing mount/fit/sanding of ailerons and flaps - won't be anything exciting to show until the bits are all in place on the wings. Then, I'll cover the ailerons and outboard flaps in Solartex.

DaleCS

Right, inboard and outboard flaps fitted with 'flap pin' fitted. I think I'll be satisfied using the pin rather than another servo - even at full deployment, the separation between the flaps is not too great and the pin not too noticeable. Byron Hellcat had this and it functioned well. Print called for 5/32" rod for pin material. Byron used a brass tube - lighter and functioned just fine, so used it again, here.

Was a little bit a pain to fit the pin - since I didn't follow print and custom built the outboard flap with 'built-up/fabric covered' construction, the pin hole in each of the laser cut ribs didn't line up well - the pin hole in the outer flap didn't line up with its inboard counterpart by half a diameter. Would like to say I built something, a nice jig or something - instead, just hands and eyes, carefully creating new hole location and then drilling into its mounting block behind the rib. End result is darn near perfect.

Now that the flaps are fitted, can fit the aileron, its hinges and finish sand - then repeat for left side!

DaleCS

One question, for anyone that wants to answer: Wing tube mounting in outer wing panel - glue it in or use a sleeve?

I have carbon fiber wing tubes, with sleeves epoxied in place in inboard wing panels. Drawings show wing tube glued into outer wing panel, no sleeves.

I know this will work, so why ask the question? Breaking a carbon tube - whether minor or major damage, cracked carbon can mean the need to replace the whole tube - if epoxied in place, this becomes a major repair involving refinishing, paint.....as I type this, I think I'm talking myself into installing sleeves in the outer wing panel. If I chip, crack or other damage a tube, its a simple repair.

Any thoughts?

Chad Veich

My Feedback: (60)

Sleeves for sure in my opinion.

DaleCS

Will order another set.

DaleCS

After fitting right inner/outer flaps, decided to fit left side, before forgetting how I had done it. Well, that's done - still some finish sanding to do. Now fitting left aileron - slots cut in trailing edge stringer for hinges, building boxes/supports for gluing hinges into. Plan to finish the hinge installation, sheeting on rear third of wing underside (to cover hinges) and the rear TE of wing tip. I've order additional wing tube material to install in outer wing panel. Then, need to order aileron, flap and elevator servos for installation, and lightening system.

DaleCS

Aileron hinges installed - not glued in, but boxes, supports built and ready to install another section of bottom sheeting. An overall shot of the wing with all the flaps hanging low and ailerons mounted. Trimmed the hinges, modifying original design. This will simplify assembly. I'll install the bottom sheeting, cut slots over the hinge boxes and then just drop these in. Without this trimming, other available option would have meant completely sawing through the TE spar. The original length for the hinge mounting area I took from the Tamjet design. When installing the mating half, noticed that this G10 material really takes epoxy and CA extremely well, and takes a fair amount of abuse without breaking. Trimming a bit off isn't going to cause any harm.

While installing the bottom sheeting, need to take care to set the incidence angle. Print calls for 1.5 to 2.0 degrees. Will include some pictures, next time, showing how I'm fixturing the wing and measuring root/tip angles. Going to shoot for 1.75 degrees, right in the middle of spec range.

DaleCS

A few more things done: Another piece of bottom sheeting installed; slots cut in buttom sheet for aileron hinges; wing tip sheeting and TE installed.

First couple pictures show how I'm setting the wing tip incidence (wash out). Early on, drew lines on outside ribs to indicate wing chord. As the dowels go through the chord, I drew another line on the inboard rib parallel to the original. Here, I've taken a couple balsa pieces and temporarily glued them to the this line. Can now set the incidence meter on these blocks and voila, get a reading. Then, used magnet jigs to hold the wing in place and four more, one at each corner, with hold down clamps, to dial in the angles - 0 on inboard rib, 1.75 degrees of washout at wing tip. And yes, if you look closely at the meter readings, I've got wash in, not wash out. Don't worry, I caught this and corrected!

Will repeat for left wing. I then have a fair bit of final fit sanding and wing-top TE installation at a aileron. The current wing-top TE at aileron is per print, but this is for an aileron that hinges at this line - the non-scale aileron from the drawings. For these quarter round leading edge, offset hinge ailerons, the TE needs to come back about 1/4". The final fit sanding will include making room for the Solartex covering. There's plenty of room for thee ailerons, but the flaps, another story - there's a balsa 'top' piece in the flap pocket on a 45 degree angle. The flaps are touching this now, in their retracted position.. Need to open this up so that the flaps, once covered, are not touching this piece.

Also, need to complete the slots through the aileron top sheeting. As the are now, they only moving down!

DaleCS

Left wing, now caught up to the right wing! Need to order some servos. Scaling down to 1/6, I may not have the room needed for the elevator servos to mount on either side of the engine/fuel box.

Had Hitec HS-755 single servo driving both elevator halves of my Byron - only about 13% more torque than calculation required at 100mph (in a dive?). Looking at Hitec HS-5645 or HS-5665 - both are 3p, 2BB, MG, programmable - using 2, one for each elevator half - this will provide 46% more torque than required, and at 0.77" wide, will fit in the limited available space.

Can spend more, but don't see the need to. The Byron flew great, never had a control issue, flying on less expensive, analog servos with less torque. More expensive, faster, higher torque servos seem to be a waste - overkill doesn't necessarily mean better or safer.

Any engineering based disagreements? Will always take constructive feedback, 'cuz I was wrong, once, long time ago, I think...was a long time ago so I might be wrong about it... Could go up to 'coreless' with HS5565 - but does a faster servo on a WWII scale fighter provide any real benefit?

All Day Dan

My Feedback: (5)

"engineering based" in RCU? A rare occurrence. You're doing just fine. Dan.

DaleCS

Well that was worth a good laugh! Thanks, Dan.

Manhattan Beach - beautiful town and Northrup-Grumman "Space Park" right there; had a nice lunch there at Brewco, down by the beach on the Blvd last summer. Thought I might be visiting more often, but son took job here in Michigan with BAE Systems.

Thanks for your input, Dan, much appreciated.

DaleCS

Received the wing tube sockets for the outer wing panels. One fit perfectly, just like the original two. The last piece was woefully undersized in ID. Supplier (TNT Landing Gear Products) suggested several ways to hone the ID of the tube, rather than supply a replacement. Since I didn't have a brake or engine cylinder hone, nor willing to buy one or find one for rent, went with a slotted wood dowel with a folded over piece of 120 grit emery cloth. Insert dowel into the drill chuck of my ShopSmith, and there I go, honing the ID of a phenolic tube! Took a number of passes, stopping to check that I hadn't gone to far, but worked out fine. Just a bit miffed about the unplanned work, additional run to HomeDepot, etc. Oh well, have a new, cheap tool in my kit that works.

2nd pic shows the outer wing tube socket installed. Goal of easily removing wing tube for transport, easy replacement if damaged, met!

Pics 3 and 4 - I really don't want to drill into the carbon tube to secure the wing. So, to secure the tube from moving in the sockets, took a scrap section of the socket, cut two pieces about a 1/4" wide, cut a small section out of each, and plan to glue them into each end as end stops as shown in Pic 3. In Pic 4, I have marked up a couple option for securing the outer wing panel to the inner panel:

1. Red Option: Mount a wood bar in the outer wing panel with an extension that will slide into the inner wing panel; bolt through the bottom of the wing, into the wood bar (I've simplified this drawing - I know I'll need a hardwood piece fixed in the inner wing panel, too, as a bolt through balsa into hardwood bar is in sufficient!)
2. Blue Option: Wood block mounted to outer wing panel rib, with bolt from inner wing panel going through ribs into wood block - accessed through wheel well

Have seen first option used on large, sectioned wings.

Second option, I used on my Byron Hellcat, but it was a secondary/backup - more for pulling the inner and outer panels together tightly for cosmetic purposes. It's also probably the easier, lighter of the two options.

Before cutting into the ribs for either option, anyone with a better idea?