Tell us what you did today on your Bearhawk Project

Carlo headed to Oshkosh next week while I head down to Tampa to close out my GPS disruption resiliency work at the airport and enjoy that refreshing Gulf Coast mid-summer weather. Did get a few shots of the elevator trim servo mount after the airplane got wings removed and moved back to home hanger for final pre-cover work. Carlo did a single tab versus the split tab plans version based on his experience with his Mustang II which has been operating without any issues for the past 12 years. Will be taking a break later in the summer to do some of his covering work and try to learn that skill-set from a couple show plane pros. You don't know what you don't know until you know it, so only one way to remedy that deficit.

Along with the lightening holes to keep weight down on the elevators and rudder and a light-weight servo and mount, removal of the tubing and cable needed for the plans-built elevator trim system helps on overall weight reduction aft of the CG. (Carlo already moved EarthX battery and a couple other systems closer to front seat based on weight savings). Case on engine mount in background of shot borrowed from some cool dude on a short grass strip NNE of Roanoke, VA. ;) Will be returned to owner at the fly-in this year.

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Very interested to hear how your trim servo installation goes - I very nearly did this myself. Should work well and eliminate any trim tab movement during normal elevator use.
 
Forming wing light lens...eventual success. Wings are done, back in the rack and going to paint in a few days. Took longer and more rivets than I had anticipated...like most of my projects :rolleyes:





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IMG_6013.jpg IMG_6014.jpg IMG_6012.jpg IMG_6015.jpg IMG_6016.jpg I have been working on the electrical system and avionics over the last couple of months. I started in the tail and have worked forward installing servos, ELT, ADAHRS, beacon, and making pitot - static connections. Fuel pumps are in and connected for the SDS EFII system. The electrical system has designed redundancy in it with two separate feeds to the essential buss. There is a switch to shed the non-essential buss to reduce load incase of alternator failure. I am using a Monkworkz generator for backup power. The electrical system and panel were designed by my friend Dean, laser cut by a local fabricator and the vinyl overlay was printed and applied by a local printer. I have two switches to wire and will be making connection between the different avionics elements. Hopefully that will be completed in the next week or two and I will begin to work on covering and painting. This whole experience has been filled with new learning and discoveries.
 
The breakers on each side are on removeable panels. The panel is also designed to be able to tip out to make it easier to work on components behind it. The trays that some of the items are attached also are hinged back at the firewall to help access. We tried to make it as easy as possible to access components but there will be some tight areas.
 
Phase one complete for N776BE at 63.9 hours. I started flying in the dead of winter last year, and went for hours over quality hours. I wanted 40. But I had CHT issues, even in winter. It took me over 20 hours, after the intial 40 hours. .6 at a time, to sort the temps. The last stumbling block was #6 CHT sensor was reading at least 50 F high. I swapped in #4 and did a short flight. Perfect.

So cowl flaps open, 65 KIAS, max CHT was 360 F with an OAT of 71 F. Cowl flaps closed still good.

No one thing fixed it. A dozen little things. But I did have one last thing that kicked my butt for a few weeks and it was a CHT sensor..

It now cools so good I wonder if it needs the the cowl flaps.

Experimental Aviation. Love it.
 
Congratulations! A dozen little things...I'm curious. I want to see the list. And did you give any thought to refine each cylinder attempting to get them equal? Pass along what you found out.

Second. When I hit 40 hours I felt like things were proven and I went to Oshkosh. But today I feel I am still building. I don't think I'll ever be done. When we keep refining things our ships get better and better. I keep thinking of stuff I want to try, measure, and know.
 
I did my first condition inspection. Everything looked good with one exception. The fuel line exiting one of the tanks was touching where it passes through the rib at the wing/fuselage connection (the aft end of the tank that is on an angle). Given that I installed the tanks while the wings were on a table in what was basically an upside down position, I suspect the tank settled a little. I had not left enough clearance to account for that and it was just touching the edge of the hole. There is enough vibration that the rib was cutting into the aluminum line.

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Replacing the line and enlarging the hole a little was easy enough but as you can see in the picture, it was going to saw all the way through soon and would have made a mess. Something to watch out for.
 
gregc said:
I did my first condition inspection. Everything looked good with one exception. The fuel line exiting one of the tanks was touching where it passes through the rib at the wing/fuselage connection (the aft end of the tank that is on an angle). Given that I installed the tanks while the wings were on a table in what was basically an upside down position, I suspect the tank settled a little. I had not left enough clearance to account for that and it was just touching the edge of the hole. There is enough vibration that the rib was cutting into the aluminum line.

Replacing the line and enlarging the hole a little was easy enough but as you can see in the picture, it was going to saw all the way through soon and would have made a mess. Something to watch out for.
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Just curious, how big was the hole to start, and how big did you make it?
 
In the "how to add months to your build" category, I've at long last found a method for making wingtip lenses to cover the bays where I will mount my FlyLEDs RV-10 "The Works" lighting system.
Much of the time was spent kluging together a vacuum forming system, as my local lead on vacuum forming help fell through after I had done the fiberglass mods on the wingtips. So I built a "homebrew" setup consisting of:
1. Household oven (modified with an insulating box big enough to hold a 24"x24" sheet of Acrylic in a frame.
2. Vacuum table (with a Shop Vac as a vacuum source)

Lessons learned:
1. Buy way more raw material than you think you need.
2. Don't be surprised when you need to buy more.
3. Speed is paramount. If it took me more than a couple of seconds to move the acrylic from the oven to the vacuum table I couldn't get a good form.
4. Foot switch to control the shop vac helped (see #3)
5. Using an IR lamp to try to reheat the acrylic while it is under vacuum on the table is a great way to overheat the acrylic and make it bubbly.
6. Getting mad, saying "I don't care about bubbles", and continuing to heat the acrylic will overheat the gypsum plaster buck you spent a week curing and make it crack/explode. Then you get to cast and cure a new buck. Oops.
7. The Vans lenses don't fit Bearhawk wingtips (for me, at least)
8. Pre-heating the buck to 45C was useful, but not sufficient to get good forming. Covering the buck with flannel really helped. I think it provides some insulation keeping the buck from hardening the plastic on contact.

I still have a ways to go on this part of the build. I'm hoping to get back to working on parts of the airplane that are involved in making it fly soon!!!
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Glad you final got the lens formed. I am still working on it. And you are absolutely right about "how to add months to your build". It is one of those decisions I made early and wish I had been guided in another direction.
 
Nice work! I think an easier solution is landing/taxi lights in the outboard leading edge and combination position/strobe on the outside edge of the wingtip. As it was, making mounting brackets for the aeroled landing lights consumed quite a bit of time. Forming the plexiglass covers was simpler as it is a flat wrap.
 
rodsmith I agree your solution sounds much easier! I think Virgil is now stocking parts and maybe lenses that that support the leading-edge landing/taxi light solution, I remember seeing something on FB about it.
I succumbed to "RV-10 Light Envy" after looking at a friend's RV-10, and the youtube videos from Russ Erb and others made the lens forming look simpler than what my "newbie" path turned into. When I was discussing the idea with my EAA Tech Counselor he said there's "a lot of opportunity for learning" when making parts like these. Now I know what he meant!!
With all that in mind, I think it's going to look (and perform) pretty well when it's done!
 
Virgil does have a kit for the leading edge lights: Landing light kit is $1300
Add LED Nav, Strobe, Position for $900
 
I am building the ribs for the horizonal stab. I am on the last one for one side. have to weld the trailing edge bushing in too. Then locate the through holes in the ribs for the diagonal brace once the ribs are fabbed. its going along pretty well so far. I expect the elevators will be a bit slower......
 
Try a wool felt on the form. It should have better insulating power and it wont melt like a polyester based felt.
Lamp are generally too in-homogeneous in their ability to heat acrylic. a linear array of incandescent filaments or quarts bulbs is better- Prob the former.
 
Bcone1381 Brooks, I did the the engine mount to fuselage first which went easy. The engine to engine mount was more work but also went well without ratchet straps, etc. I started with the top two isolators (easy), let the engine weight help with positioning the bottom two which took some trial and error to get the angles and alignment just right to get the bolts to slip in all the way to catch some threads with the nut. I had the engine hoisted from the garage rafters and a engine leveler to help with the fore and aft tilt angle of the engine to match that of the fuselage which was almost level. Second set of hands with a helper was beneficial as well to get things lined up in position while fitting thru bolts. Took about an hour and a half from setup to completion. We were working very carefully...
 
Painted flight controls and stuff stored small.jpg Painted flight controls small.jpg Got my 2nd wing back from the paint shop along with door, windows, struts, fuel tank covers, flaps ailerons, etc. Panel from AFS came in last week. I am slightly overwhelmed with starting work on the cowls and firewall stuff. At least I'm in a heated workshop next to the house for the winter.

2nd wing and stuff.jpg BEARHAWK_PATROL_HDX_N826ZM.jpg !
 
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Gerhard Rieger said:
I started the painting process, more time consuming than I thought, but satisfying. Need to take the boot cowl of and paint it, then paint all the ceconite covered parts with echofill from Stewarts. Getting there.
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Gerhard, a theme on this post is that painting is time consuming, and that you are "Getting There." I'm curious how long you have been at it. When did you begin your build?
 
Decided to cut out some 12mm wide rib stitching reinforcement tapes from a piece of scrap Oratex with the laser. Very gratifying and more precise than my scissor technique. For those curious, the laser has a 1.8m by 1.2m cut area with a motorized Z height table. 80w laser

Astute observers may see the scrap ply in the upper part of the bed that was from my Bearhawk sign for the hangar.

https://youtu.be/Pb_nAjnT-aA

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IMG_6132.jpg After starting in February installing servos and wiring in the tail of the fuselage, I finally have the panel and most of the wiring finished behind the fire wall. It is a big step forward that has taken a while.
IMG_6192.jpg Today a couple of friends, Keith and Dean, came over and got me started on fabric covering. One trim tab covered.

IMG_6188.jpg IMG_6191.jpg Then an aileron.

IMG_6184.jpg IMG_6195.jpg What would we do if we didn't have caring people in our lives that motivate us to keep moving forward. It takes a community to build an airplane.

HAPPY HOLIDAYS AND MAY YOU BE BLESSED BY FAMILY AND FRIENDS IN THE NEW YEAR!
 
Sweet looking panel. Looking forward to seeing the covering progress!
I’m at the “servos in the tail” step now…
 
I fabricated a cowl cover. Flying in Michigan during winter has limits if we loose engine heat and have no preheating available. My first step to expanding winter Utility is the cowl cover so my wife and I can go to breakfast or lunch someplace then start a warm engine.
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In TX this year, that hasn't been a problem, daily in the 60-70's and sunshine. One of these days it might actually get cold, but not today :)
 
I felt some warmth last a few weeks ago on a cold morning near this gear leg fitting. I fly lean of peak so that may mask CO issues if it’s exhaust that is my source of heat.

3M strip caulk is my fix. I used it in the window sealant and it’s a real quick job to seal up this too.
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I've finally got pitch and yaw servos, along with the ELT, mounted.
Also installed the new rudder pedals provided by Virgil and his team. These replaced the ones that came with my very old kit, which predated a couple of engineering changes I deemed important:
1. Welds at the end of the cross tubes: February 2013 Engineering Change Notice
2. Tabs at the ends of the pedal tubes to keep pilots' feet from falling off the pedals
I also took the opportunity to correct the rudder pedal placement, as the first builder had installed them too far aft which created problems with brake geometry and pedal function. Thanks to all those who contributed to the great forum threads on that topic. That info was really helpful as as I was trying to understand, and then untangle, that issue.
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Created template for boot cowl access panel to be placed on each side of boot cowl. Should allow very good access to things under the top skin and behind the panel as well as brake cylinders, thru firewall fittings, etc.
 

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After being on vacation all last week, and being stuck on the couch sick with the flu, I finally was able to get back to the hangar and start on the evil deed. Covering the fuselage. Left side mostly done. Vertical fin and fuselage transition was freaking me out, but I stuck with my game plan and it all worked. Fokker Red Oratex. Got a couple wrinkles on the longeron to work out, but that's it. The fabric is attached to the inside of the aluminum stringers. Then a triangular finish piece will go on top with trim tape on the edges. Rib stitching etc.

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Covering is finished and got the fuselage off the rotisserie for the last time. It's on the wheels! Time to install the tail feathers and get the controls hooked up.
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And the panel is nearly populated. Waiting on the SDS EFI control panel.

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I am learning how to upholster and make gear. I picked up an old professional grade walking foot machine a few weeks ago. The head weighs 72 pounds and has on oil drip pan.

Its clutch motor went one speed and the foot pedal ability to feather and control speed was so so sensitive. Today I replaced it with a servo motor and it has a knob to scale back its “wide open throttle” speed.

Next step is to disassemble the work I did on my seat cover project and fix a few things. That’s how things have always gone for me. “I could have done X better. Let’s redo it and make it right.”
 

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Bcone1381 said:
I am learning how to upholster and make gear. I picked up an old professional grade walking foot machine a few weeks ago. The head weighs 72 pounds and has on oil drip pan.
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Your machine is awesome! I have the Juli LU-1508NH and it is wonderful to work with. I have another straight stitch Juki, and a zigzag Consew that are each setup for different tasks. Send some pics of your work please when done.

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Put nutplates for 8-32 fasteners on the forward edge of tunnel. Aft edge I am using 8-32 clip nuts. Would like to do the same on the sides of the tunnel, but some of the matched holes for skin and tunnel are too far or too close to edge or flange to use clip nuts. Looks like a mix of clip nuts and nutplates. Maybe trim the tunnel sides to use mostly clip nuts? That would leave me only a couple of nutplate to install where the flange interferes with the clip nuts...thinking out loud here :rolleyes: tunnel to boot skins.jpg
 
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The seat is all done. I installed a few bells and whistles. A pocket holds the five point harness central buckle. A sleeve holds the fuel sampler. The seat bottom cushion is secured to the seat frame with snaps. Comfort wise, I feel like you almost cant make an error using memory foam.

The seat back has two parts, one slide over the seat frame and the second part holds the foam. The back has flaps secured with velcro that wrap around the frame. This is not my design. I copied a very well made LSA seat from Sport Aircraft Seats.

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Made doubler to mount EFII fuel pump module to forward lower boot skin former. Should be able to locate pump prefilter in that area also with room for servicing thru the access panel. Removing the gascolator spin on bowl gives enough room to remove the pump if ever necessary.

Fuel pump dry fitment 2.jpg fuel pump doubler and final drill.jpg
 
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New style pre pump filter (FF-3) from EFII can mount directly to fuel boost pump module. Save space and fittings. I was pleasantly surprised!

FF3 fuel filter from EFII screws directly into inlet.jpg
 
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Got the landing lights installed. Went with the Flyleds. I took a pice of 2” pvc pipe added a bolt lock washer and a couple of nuts and created a jig to push the lens up into yard leading edge. It made it easy to drill the lens so they would line up with the nut plates. Took longer than I figured just like most things. Overall happy with the results. Has anyone used a gasket to help them be a little more water proof?
 

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After I finished up another panel project, I was finally able to get to my own. Over the last 9 months or so, I had made a couple good deals on a GNC 355 and an AV-30, so I retrofitted my panel to make it fully IFR. I didn't want to go through designing and validating a whole new panel cutout, so I made pieces to move things around. Maybe I'll get around to cutting a whole new panel at some point. Or maybe I won't...

I had an air gizmo iPad mount on the right that I never used since everything is on the glass panel, and a 7in HDX that was originally intended as the Engine Monitor/MFD, which I felt was a waste of a screen, especially when flying with another pilot on the right. The GNC355 adds a 2nd comm now, and the AV-30 serves as redundant ADHRS with its own backup battery.
 

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I made my panel in 3 pieces intentionally, with the middle piece being wide enough for a navigator, even though I don't plan on one. I did it to make servicing easier - one piece makes it harder and more time consuming. So far it has been a "good idea".
 
Wire runs from rear to front.jpg Rear wires forward.jpg ACM shelf installed.jpg ACM mounted.jpg

During the past week, I've started to bring rear wires forward to behind the panel. Also fabricated a mount for the Advanced Flight System ACM and placed it behind the panel. Lots of stuff to bring forward when you include all the wing wiring!
 
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filedata/fetch?filedataid=19626Thought I had better contribute some posts. February and March I spent covering, stitching and taping. Found that I like the stagger wing beech knot better that the modified seine knot.

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I did a little 3D printing along the way. This is a form a friend designed in Solid​works to make rudder cable exits. I used PA6-GF filament and annealed it. It makes it a very tough material.

​

filedata/fetch?filedataid=19634​Received my Catto 78" composite CS prop.​​​​


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I made a bulkhead and Dean welded some tabs on for the inspection cover on the bottom of the tail. It will give me good access to inspect and maintain items in the tail of the aircraft.

IMG_6456.jpg IMG_6421.jpg In the last week I have been working on the interior and outside faberic.

























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Time to reawaken this thread! I've hit a major milestone on my 4-place "A" model QB, having completed the majority of the "stuff" related to tailfeathers and things aft of the cabin that needs doing before covering. Control cables made up, elevator balances cast, VHF nav antenna mounted in vertical stab, Comm 1 antenna mounted above the rear seat, and 3 autopilot servos and ELT all mounted and rigged (temporarily).
I have the fuselage on the diagonal in a small-ish 2-car garage, just big enough to have either the tailfeathers on, or firewall forward in place, but not both! It's time to pull the tailfeathers off, rotate the fuselage 180 degrees (nose out, tail shoved in a back corner), and get to work on fuel system, instrument panel (structural), fuselage wiring, and anything else that must be done before fabric and paint.
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Shop upgrades! Built a Mezzanine to increase and organize floor space. Added a bunch of LED shop lights. Several options for overhead lifting which helps hold the wings when working on wingtips with one end off the rotisserie. Meanwhile, doing avionics wiring while waiting for exhaust and prop to arrive someday from Hartzell.

If anyone is interested in doing a build, come and visit us here at Pegasus Airpark, 5AZ3. We love visitors!

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I've managed to cram the SPRL Fuel Selector, Barrows gascolator, EFII prefilter, and EFII boost pump, all under the left front seat floorboard of my A-Model 4-place. It's a tight squeeze but it does fit! My fuselage included the gusset under the front end of the flap handle with the idea of putting the selector there, but I liked the ergonomics of putting the selector under my right thigh.
Put another way: the need to release shoulder restraints to reach the fuel selector (especially in an engine-out scenario) made the original (waaaay forward) fuel selector location a non-starter for me.
 

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That looks good Dave. Despite your fuel valve location, I think you are going to want a shoulder harness with an inertial reel to reach the flaps. That was not something I wanted but I found necessary, it is still a stretch for me. I only installed the inertial reel on the pilots side.
 
Thanks! Yep, inertia reel is not my preference but I agree it will likely be necessary. That flap handle is a long way off!
 
Applying stewarts ekofil
 

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rodsmith said:
That looks good Dave. Despite your fuel valve location, I think you are going to want a shoulder harness with an inertial reel to reach the flaps. That was not something I wanted but I found necessary, it is still a stretch for me. I only installed the inertial reel on the pilots side.
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Where did you find the inertial reel? Or did you buy an entire harness? I have scoured the internet trying to find one. Must be searching for the wrong thing.
 
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