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Author Topic: Brodak F-8F Bearcat  (Read 4737 times)

Offline Jim Carter

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Brodak F-8F Bearcat
« on: January 28, 2018, 02:10:19 PM »
Hello everyone!  I had some communication with Charles, Aviojet, regarding posting the build of my Brodak F-8F Bearcat and I decided to accept his offer.  I hope each of you enjoys the posts.  Oh, and just to let everyone know in advance, when I build, I've developed a habit (whether good or bad) of documenting each step I do similar to a daily diary. and I'll be posting pretty much just as I wrote each days work.  So, with Charles' permission, let's get started :)

Brodak Bearcat

A few months ago, I watched a YouTube video showing the history of the US Navy’s Blue Angels and for some unknown reason, that video really tweaked my desire to build a model of a Bearcat.  Since I’m currently spending most of my flying time on control line it didn’t take me long to research the available kits of this aircraft.  A few years ago, I built one of the Brodak Profile Bearcats for a fellow who was active in carrier flying so I knew the Brodak line would be a good product choice for selection.  Over the course of the next couple of weeks, I was able to entice some of the members of our little flying group, The North Brevard Figure 9ers, to join me and build one of these models so we could someday, field a full squadron of these planes.  Six of the guys bought into the idea and the idea came to life.

I ordered the kits plus the needed tanks and wheels and on Saturday, October 7, 2017 the kits were distributed and Sunday, October 29, 2017 I opened my Brodak BEARCAT to review the plans for a moment then I tried to see if I could find a set of retracts for it.  I’ll probably settle for a set of E-Flite .40 size electrics, if I can afford them.  I had the plans copied and scanned onto my flashdrive for future reference.
With all that done, I decided to begin assembly of the Brodak BEARCAT.  It really is quite a nice kit; the laser cutting is very good and the balsa is very nice.  I read through some of the instructions then began punching out some of the diecut parts and grouping them together.  Since I don’t have one of the Brodak wing jigs, I decided to begin construction of the fuselage.  For the most part, I did my best to follow the instructions as spelled out in the very informative manual but honestly, I knew I was going to deviate somewhere before the thing is completed!  I started by laying each of the parts in the relative positions according to the plan before beginning to do any gluing.
 
As I was about to begin, I noticed that the fuel tank I had received was the wrong one; I received a BH-589 rather than the recommended BH-498.  Both are 4 ounce tnks but the 598 is taller and shorter than the recommended tank.  So, I placed an order for the correct one, as well as a request for the decals to be printed in yellow keeping in line with the photos of the real aircraft. 
    
I began the work of framing the fuselage.  With that essentially done, I a decided to deviate from the instructions and glue up the parts for the vertical stabilizer.  From there, I began framing the lower cowl at least according to the instructions and the photos provided.  They honestly didn’t make any sense to me, even with the photographs but the problem most likely is mine, as I write this.  Frames A-C and B-C don’t fit or either I put something together wrong.  According to the plan, it looks like it’s one piece but the parts don’t fit as smoothly as I would have suspected.  If it is truly one piece, the plan is poor in depicting how it should be assembled and there are no clarifying photos in the instruction book.  Anyway, I had to trim the frame B-C so that it would fit between the sides against the front of frame B.  Then using a piece of parchment paper I fitted and clamped frame D-C against frame D, then fitted the F-2 cowl floor between the frames B-C and D-C.  I used some Windex to soak and soften the ends of the fuselages sides so that they could be formed around the A-C frame.  Next, I fitted the frame A-C against the cowl ring and held it in place using a number of pins.  Finally, I added the 1/4" x 3/8” stringers to complete the basic framing and then give consideration to sheeting.
    
With that done I marked and began fitting the upper cowl block.  Next, I began the process of sheeting the lower cowl.  I used a mixture of ¼ x 3/16 and 3/16” sq. balsa sticks to get the shape I’ll need.  Over the course of the afternoon, I was finally able to come up with a reasonable shaped and fitting of the lower cowl.  I used a piece of brass tube as the slot for inserting the 4-40 hold down bolt that gets screwed into the blind nut hold down block.
    
Once I was satisfied with the fit and seating of the lower cowl, I marked the location for the engine glow plug and then opened the cowl sufficiently to give a 3/16” clearance around the OS 40 FP cylinder head.  I also opened a couple of holes for the fuel tank fill and vent lines.  I applied a coat of Z-Poxy Finishing Resin to the engine and fuel tank compartments.  While the epoxy cured I decided to assemble the horizontal stab and elevator.  It was a fairly straight forward process with no particular issues.


Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #1 on: January 29, 2018, 08:25:16 AM »
This portion of the build documentation summarizes actions that occurred over the period of about a month and it began the shaping process of the horizontal stab assembly, the forward portion of the fuselage and the wing.  I followed the instructions using the appropriate sizes of brass tubing to rough sand the elevators halves and the horizontal stab as required.  I was very pleased with the final results and finished by rounding the leading and trailing edges as shown on the plan.  I opted to use the Brodak brass mounts, BH-745 for the elevator joiner and after marking all of the locations I made the necessary slots and used some Brodak EZ hinge, BH-927, rather than the Dubro hinges provided to mount the elevators.  The elevators were in place and the setup looked good.  I ran out of EZ hinge and will need to get some more before the surfaces can be permanently glued in place.

When I resumed work on the BEARCAT, I used one of the Dremel grinders to carefully grind the slot for the tail wheel strut then used thick CA to sandwich the wire in place as well as the maple anchor block.  Next it was a fairly simple matter to glue the mount in place under the stringer.  At this point I’m way out of sequence with the instructions, so I decided to begin planking the forward section of the fuselage.  Rather than trying to wet and shape balsa sheets, I opted to use some 3/32” x ¼” sticks.  Personally, I think this is a bit easier but to each his own!

Once the planking was done, it was time to spend a few minutes shaping the upper cowl block.  With that done, I shaped and installed the landing gear blocks followed by shaping the wing leading edges and applying the leading edge sheeting.  Doing this without a jig was a bit of a tedious process but I believe I was able to avoid building in any significant warp.  Next, it was time to fabricate the bellcrank and leadout wires according to the instructions.  This is the first time I’ve ever built a model using the long mounting post and it will be interesting to see if there is any difference in performance especially since it’s using a 4” bellcrank. 
    
During another session, I worked to fit and join the wing halves.  It was quite a task especially trying to keep from building any positive or negative incidence into the wing.  I added some scrap balsa to reinforce the joints inside the top and bottom sheeting and so far, it looks good.  I took a bit of a break to update the logs and transfer a few photos.  I completed the mounting and installation of the bellcrank assembly, the adjustable lead out guide along with the addition of the cap strips for the wing.  I used thick CA to glue the leading edge sheets in place then prepared to begin the initial shaping process.

Offline Avaiojet

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Re: Brodak F-8F Bearcat
« Reply #2 on: January 29, 2018, 07:09:18 PM »
Jim,

Great build! As always. H^^

I had a Brodak Bearcat kit but sold it. Can't remember who bought it?

I have the correct Blue Angles graphics.

So let me know when you need the graphics and I'll get them out to you. No charge.

Thanks for the Build.

Charles
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Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #3 on: January 30, 2018, 09:34:08 AM »
Jim,

Great build! As always. H^^

I had a Brodak Bearcat kit but sold it. Can't remember who bought it?

I have the correct Blue Angles graphics.

So let me know when you need the graphics and I'll get them out to you. No charge.

Thanks for the Build.

Charles
Thanks in advance.  I'll be breaking the build in segments, daily and each segment will cover about two or three weeks worth of actual time, if that's alright.  As it goes forward through the research segment, you'll see the color of the graphics I'll be hoping to acquire.  I have the ones that came with the kit and I can send them to you so the size and font will be similar, should anyone else need them.

Online Perry Rose

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Re: Brodak F-8F Bearcat
« Reply #4 on: February 07, 2018, 02:35:01 PM »
I built one a few years ago. It's not an easy build but it is a great flying plane. .46 LA, all blue color.
I may be wrong but I doubt it.
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The worst part of growing old is remembering when you were young.

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #5 on: February 08, 2018, 07:35:00 AM »
I built one a few years ago. It's not an easy build but it is a great flying plane. .46 LA, all blue color.
Thanks Perry.  You're right, it is a bit of a challenging build but I and another of my flying buddies went over the top (so to speak) and modified a few things with no idea whether it was a good idea!  ::)  %^@

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #6 on: February 08, 2018, 07:59:01 AM »
After shaping the leading edge, I decided to do a test fit of the wing and fuselage and it looks pretty good.  I resumed work on the BEARCAT and worked to shape the wing tips.  I left the outboard tip solid whereas the inboard tip has to be hollowed out to allow for the adjustable leadouts.  During my next session in the workshop, I began by hollowing out the inboard wing tip for the BEARCAT and by 1030 or so I had a pretty nice wing tip shaped and ready for mounting.  I’m not sure but I may have the slot a bit too wide but I’ll deal with that when it’s time to cover the wing.  I mounted the inboard wing tip.
 
I’m torn as to whether to make the wing removable so I began working on the flap assembly.  I read a portion of the instructions, then marked the hinge locations and center lines for the flaps, then temporarily mounted the control horn to see how it seated.  Now, it was time to begin shaping the flaps.  I followed the recommendations to use the three different sizes of music wire and although it took a bit of time using 80 grit down to 250 grit sandpaper, the finished product came out acceptable.  Next, came the fitting and aligning of the flaps using E-Z hinge.  I chose these rather than the Dubro hinges because of the likelihood of misaligning one of them and ending up with a binding or twisting of the control surface.  Besides, I think they are easier to install, pin and replace if necessary, at this point of construction.
    
I added the top and bottom center sheeting and with that done, I tack glued the wing to the fuselage and began the slow process of aligning the horizontal stab assembly level and aligned with the wing.  At that point, I was able to install the two sections of the elevator pushrod.  The instructions call for soldering the joints but I opted to use two 5/32” Dubro wheel collars.  I applied a good coat of Thread Locker to secure them to the pushrods joint then checked the alignment of the wing to the horizontal stab alignment.  I went over all of the essential areas of alignment again and made any needed adjustments until I was satisfied.  At that point, I applied thin CA to all of the hinges and glued the wing in place to the fuselage, adding necessary shim and filler as needed.

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #7 on: February 08, 2018, 08:30:52 AM »
I opted to reset the OS 40 to get a feel for the fit of the lower cowl and begin the shaping process.  After that, I mixed up a small amount of JB Weld and applied it to the joints and point of overlap of the elevator pushrod connection.  I certainly shouldn’t have any problem with it coming loose due to vibration.  Next, I completed the lower sheeting for the wing then applied the sheeting to the aft portion of the fuselage.
    
During the next session, I focused on completing the bottom aft sheeting along with adding the tail block and the braces to protect the pushrod from excessive flexing and vibration.  I set to work applying the turtle deck sheeting for the BEARCAT and when it was done I test fitted the vertical stabilizer. When I was satisfied I attached the vertical stab and rudder assembly then competed a fair amount of shaping and sanding in preparation for finishing.  I spent a few minutes going over some various ideas for mounting the fuel tank and the fill and overflow lines.

On Saturday, December 23, 2017, my flying buddy came by for a visit and we spent a few minutes kicking around the idea of tearing into the Bearcat’s wing to install some retracts.  We decided that it was doable but it’s going to be quite a job!  After he left, I placed an order with Tower Hobbies for the Insignia Blue Monokote and a Dubro muffler extension for the OS 40 FP engine.  I spent the next couple of hours pondering the best way to configure the fuel line fill port on the BEARCAT.  I decided on using a Dubro Filling System, Dub-840 that I had on hand. 

During this session, I was able to shape the nose, mount the fuel tank and get it satisfactorily seated into the fuselage.  Then, I turned my efforts to  making a second attachment bolt for the removable lower cowl before applying a coat of finishing resin to the inside of the engine and fuel tank compartment.

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #8 on: February 12, 2018, 10:42:05 AM »
I received my order for the muffler extension and the roll of insignia blue monokote and began the session by mounting the muffler extension, Dub-699, to the BEARCAT.  It looks pretty good.  I also test mounted the removable cowl and it worked just fine.
 
Well, it was time to commit to the installation of the retracts.  For this I opted to use the E-Flite 15-25 size electric retracts.  I used the fixed strut from the kit to figure out the length of the retractable strut where the axle and wheel should be mounted.  Then I placed the retract unit over the fixed block so that the pivot point was in the same position as the fixed strut thus allowing me to estimate and mark just how much of the 1/16" balsa sheeting would need to be removed from the wing for a 2-1/2" wheel to fit.  With sufficient sheeting removed, I estimated the depth of the axle and wheel assembly so I could remove the appropriate amount of rib R-2.
    
Because the fixed strut was shorter than the retract unit, I decided on making the retract beam mounts long enough to extend past the R-4 rib.  This meant cutting four hardwood (4) beams 4-1/2” long and mounting the retracts about 61 mm from one end of the beam.  The width of the beam mounted retract assembly was 35 mm so I carefully removed the fixed gear mount and then cut the beam mount seating slot approximately 25 mm from the edge of the wing sheeting into ribs R-3, R-4 and R-5.  Also, I fabricated a 1/16" plywood doubler for each of the R-5 ribs to strengthen them.  I really felt silly because normally, I make templates of all kit parts for future repairs and or replication but this time, for some unknown reason, I didn’t do it thus it was a bit of a pain making a decent doubler. 
    
With them cut and fitted, the doublers were superglued to the R-5 ribs then test fitted the beam mounted landing gear.  This was a slow and tedious process because I had to make sure the gear unit was recessed enough so that the unit is below the wing sheeting and yet the gear doors would be flush with the wing sheeting.  Also, the angle of the gear would place at least half of the wheel forward of the wing leading edge to avoid nose overs upon landing.
    
Also, to be on the safe side, I added a length of plastic tubing to act as a shroud and guide protecting the control line that will be running through the inboard wheel well.  Once I was satisfied with the interim placement of the retract units, I began the process of mounting them into the wing and reinforcing the joints.  This definitely was a challenging modification but it was completed and functioning by the end of the session.  Next, I fabricated some spar webbing to go between the ribs R-2 to R-5.  I fabricated the wing cover sheeting to enclose the retract assemblies, fitted and glued the covers in place and then shaped them allowing sufficient clearance for the wheels in the wheel wells and the addition of the gear doors.  With that done, I made an access hatch in the bottom of the outboard wing for the battery and receiver.
    
I added some reinforcement to the R-2 and R-3 ribs in case there is some bouncing or movement of the battery.  I certainly wouldn’t want the battery breaking through one of the ribs on a bounced landing.  Next came the installation of the radio gear.  To this end, I used a small dab of medium CA to hold the retract connectors in place against the wing skin.  I applied a bit of 5-minute epoxy onto the underside of the top wing sheeting between R-3 and R-4 to strengthen the inside compartment that will be holding the battery and between R-1 and R-2 since I opted to use a small piece of Velcro to hold the receiver in place.  As for the switch, it was mounted on the actual hatch and fitted on the inboard side of R-3 thus keeping it out of the battery compartment which is between the ribs R-3 and R-4.
    
I successfully tested and cycled the system a few times and was satisfied that the basic installation was sound.  Only actual flight testing will shake out any problems that need to be corrected.  I fabricated the liners for the BEARCAT wheel wells.  With 2-1/2” wheels I knew I would have to make the wheel wells at least ¼” larger in diameter to afford a nice fit but then again if there is any bending of the gear due to a bump or rough landing it could prevent the smooth operation of the retracts.  I used 1/64” ply to line the cutouts for the wheels using two pieces of 1/64” x 2” x 4” with about ¼” overlap to make a 7-1/2” long piece.  Then I had to fit, adjust, trim and re-trim such that the liner allowed the free operation of the wheel.  Once satisfied, it was tack glued in place using thin CA then trimmed flush with the surface of the wing sheeting.
    
When both retracts were operating satisfactorily, I took a few moments to make a brief video or them cycling up and down.  The setup looks good.  Now to mount the landing gear doors.  This required a bit of creativity because the axle required the use of a piece of scrap balsa as a spacer between the door and the axle also the mounting holes had to be relocated from the kit positions.  I opted to use a couple of sets of 2-56 bolt and nut sets to clamp the gear doors to the axles.  The tricky and patient part came when trying to ensure the gear doors seated properly.  Because the retracts are a significant modification to the wing it will be almost impossible to completely enclose the wheel well without a near complete redesign of the wing and I’m not willing to do that since this is not a “true scale” model.

Offline Avaiojet

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Re: Brodak F-8F Bearcat
« Reply #9 on: February 13, 2018, 08:03:28 AM »
Jim,

Looking really good!

Robart wheels. What size are they?

Charles
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Offline Glenn (Gravitywell) Reach

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Re: Brodak F-8F Bearcat
« Reply #10 on: February 13, 2018, 12:42:02 PM »
Hi Jim, just wanted to say how much I am enjoying your build.  You have raised the bar on how a build should be done.  Almost too much information to take in and the build tips are super!  Thank you so much for taking the time. H^^
Glenn Reach
Westlock, Alberta
gravitywell2011 @ gmail . com

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #11 on: February 14, 2018, 06:53:35 AM »
 :)  Thanks Charles!  Thanks Glenn!  As for the wheels, I ordered the Robart 2-1/2" but as I'll be mentioning a bit later in the build, I had to replace them with 2-1/4" wheels.

Glenn, I appreciate your words.  I struggle with just how much info to add especially if I'm doing something different from the plan or published instructions.  Yet I recognize that any one who would seek to follow a similar path would also have the skills and knowledge to do their own thing.  I just hope the process and end result is acceptable to fellow model builders  :)

Offline Dane Martin

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Re: Brodak F-8F Bearcat
« Reply #12 on: February 20, 2018, 06:30:43 PM »
I think you can never add enough info in a build. I don't post mine as a how to, but sometimes people get ideas from how I do stuff. My building is influenced by 3d and giant scale RC, free flight and pylon racing. All 3 are set up differently. But they all have merit in what you use in CL. My push rods are literally what I build a tail pitch push rods for my RC helicopters. Maybe some people have never seen that before. You just never know what you put out that, some people may use.
And of course, the info and suggestions come in from helpful folks all the time. Build away Carter. The rest of us are loving it.

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #13 on: February 27, 2018, 01:52:00 PM »
I began the session by fabricating the liners for the BEARCAT wheel wells.  With 2-1/2” wheels I knew I would have to make the wheels at least ¼” larger in diameter to afford a nice fit but then again if there is any bending of the gear due to a bump or rough landing it could prevent the smooth operation of the retracts.  I used some 1/64” ply to line the cutouts for the wheels.  I tack glued two pieces of 1/64” x 2” x 4” with about ¼” overlap to make a 7-1/2” long piece.  Then I had to fit, adjust, trim and re-trim such that the liner allowed the free operation of the wheel.  Once satisfied, it was tack glued in place using thin CA then trimmed flush with the wing sheeting.
    
When both retracts were operating satisfactorily, I took a few moments to make a brief video or them cycling up and down.  The setup looks good.  Now to mount the landing gear doors.  This required a bit of creativity because the axle required the use of a piece of scrap balsa as a spacer between the door and the axle also the mounting holes had to be relocated from the kit positions.  I opted to use a couple of sets of 2-56 bolt and nut sets to clamp the gear doors to the axles.
    
The tricky and patient part came when trying to ensure the gear doors seated properly.  Because the retracts are a significant modification to the wing it will be almost impossible to completely enclose the wheel well without a near complete redesign of the wing and I’m not willing to do that since this is not a “true scale” model.  George, one of our club members sent me a couple pictures of his Bearcat.  He’s using a Rojet rear exhaust engine in his and did a real nice job of enclosing it but he's not going to install retracts.

I resumed work on the BEARCAT and this time I pondered why my canopy didn’t fit.  At that moment, when I looked at George’s cockpit, it dawned on me that I had framed up the fuselage incorrectly specifically in the area of the cockpit.  So, I pulled out the plans to check some dimensions and come up with a fix.  I’m going to try and correct this.  I started by cutting and fitting a couple of pieces of scrap 3/32” balsa into the cutouts that would frame the cockpit then making a template from the plan top view that allowed me to mark the location of the cockpit.  Once the area was cutout it was just a matter of shaping and finishing the surface so I could test the canopy over the cockpit area.  It seems to fit all right and it doesn’t look too bad.  Next, it was time to give thought the best way to provide a bit more exhaust area for the cooling air.  I reviewed some of the photos of the real Bearcats and noted that the exhaust pipes extended alongside the fuselage but over the leading edge of the wing.  After looking over the structure of the model, I decided to attempt something similar but having it actually allow some of the engine heat to exit the plane.   I made a rectangular cut, 1” x 2”, approximately ½” aft of the D-B frame then inlay a piece of 3/32” x 1” wide balsa at an angle of about 10 degrees (actually the angle was set to allow the exhaust pipes a nice snug fit).  The exhaust pipes were made using three 1” x ¼” i.d. brass tubes that were tack soldered together on one side.  I wasn’t too worried about a complete solder joint as the fit of the tubes should be somewhat snug once set in place.
    
Once seated and glued in place, I used a ¼” drill through the tubes to ensure there were openings through the frame and into the engine and fuel tank compartments.  I used thin CA to seal the wood from any actual exhaust residue once it begins operation.  I’ll probably use a thin application of finishing resin to ensure a good seal and protection for the wood.

I didn’t come into the workshop until a little after noon and when I did, I powered up and resumed work on the BEARCAT.  During this session, I spent a bit of time applying a coat of filler to fill some of the cracks and joints then applied some finishing resin to some bare areas of wood in the cowl and fuel tank areas then hung it on the rack to cure.  Also, I removed the motor, battery and opened the outboard portion of the wheel well so I could have easier access to the receiver because, at the moment, I can’t remove the switch from the receiver.  At the same time, I believe I should find and order a smaller receiver battery.  It doesn’t need much capacity as over the course of any flight session the retracts would only be cycled five or six times.  I hung it on the rack overnight to allow the filler to harden.

The next morning, I took the BEARCAT off the rack and worked a while to complete the sanding of the filler I applied a couple of days ago.  After that, I took it into the backyard so I could apply a good coat of Balsarite to all the wood surfaces in preparation for covering.  I left it outside to dry for a couple of hours before bringing it back in to hang on the rack for the evening.

During this session, I started by adding some filler to the BEARCAT aileron joints because I forgot to do them a few days ago then I hung it back on the rack to dry for a couple of days.

When I came back into the workshop, I pondered the idea of using the 6v AAA battery pack I have on hand for the BEARCAT but it’s old and probably won’t hold a charge for any length of time.  I set up the Venom cycler and put the battery through a number of charge/discharge cycles to see if it has any life left in it.  I spoke with Fran about it and she agreed I should just order a new one and be done with it.  Nevertheless, I cycled the battery about three times and it seems to have brought it back to life a bit.  I connected it to a small motor and just let it run for about 15 minutes or so and that should be equivalent to 4 or 5 cycles of the retracts, as far as load is concerned and it seems to be okay, so far.  Anyway, while that cycling was going on, I spent some of the time sanding the filler for the BEARCAT ailerons and I believe the surfaces are ready for covering.  I spent a few more minutes working on the BEARCAT retracts, testing the setup using the old 6v AAA battery pack and after about a half dozen cycles it generally seemed like it was okay, for the most part. There were a few missed cycles but it may have been either the batteries, the wheel well being too tight of poor transmitter switch action.  I just don’t know but I’m sure I’ll figure it out, sooner or later.   I resumed work focusing on adding throttle control.  I mounted the engine and opened the cowl area as needed then opened a hole for the needle valve.  I cleaned and soldered an extension to the needle valve for an easier adjusting and setting and finished the process by coating the soldered area with some JB Weld.

I came into the workshop to give consideration to mounting a throttle servo in the BEARCAT.  I removed the engine then realized that I needed to fix the carb because it was a loose.  I mixed up a batch of JB Weld and used it to seal the carb.  I began reviewing the servos I had on hand and decided on the old Traxxas 2060 mini servo which seemed to fit just right.  I made up an adjustable pushrod, test fitted it to the servo and the engine and everything seemed to work.  I used some double-sided tape on the side and bottom of the servo to hold the throttle to the resin coated surface.
    
At the same time, I decided to re-position the receiver to a position on the underside of the top wing skin between R-3 and R-4 with a piece of Velcro. 
Using two 6” servo extensions, I was able to complete the relocation, placement and installation of the radio system and everything worked nice and smooth.  To ensure there would be sufficient room in the wheel well in case a touch-and-go or landing is less than perfect, I decided that I would order a set of Robart 2-1/4” wheels.  I completed the fitting and adjustment of the removable cowl with the engine, muffler, and fuel lines installed.

I came into the workshop and began the covering process for the BEARCAT.  By 1830 or so, I had completed the top and bottom of the horizontal stab assembly and the receiver box cover and the bottom wing of the BEARCAT.
   
The following day, I came into the workshop and started back working on covering the BEARCAT.  I focused on covering the gear doors, the removable cowl and the openings of the wheel well with some of the scraps left over from covering the wing.  At this point, I’m out of covering to finish the project.  I mounted the landing gear doors for the sake of storage and hung it back on the rack to await my order for some more monokote.

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #14 on: February 27, 2018, 02:40:00 PM »
Friday, February 2, 2018
I received my order with the monokote and came back into the workshop to resume covering the BEARCAT.  The problem is that the covering is a slightly different shade.  It’s not bad but I can see the difference and I believe it’s going to hurt for points when it comes to judging.  Nevertheless, I have no choice, I began covering.  I worked until about 1850 or so when I decided to stop for the evening.  I really feel bad about the difference in the shade of monokote but there’s nothing I can do about it now, other than sell it when I’m finished, which may be a viable option.

Saturday, February 3, 2018
I resumed covering of the BEARCAT and by 1816, I completed the covering, painted the inside of the cockpit, re-mounted the engine and muffler and documented the whole thing.  I even started painting the pilot figure to go in the cockpit.  As it sits, I’m relatively pleased with what I see.

Sunday, February 4, 2018
I resumed painting the pilot figure for the BEARCAT.  While the paint dried, I downloaded a picture of a BEARCAT cockpit, sized it to a 1.46 then printed it and glued it into the model.  I like it!  Next, I test fitted the pilot figure in the cockpit and again, I like what I see.
    
Wednesday, February 7, 2018
I sent an email to a fellow who says he can make the decals for the BEARCAT, glued the pilot into the BEARCAT and added the terminations to the leadouts.  I also sent a second email to Brodak MFG to see if they would consider making decals for the Blue Angel Bearcat but again, I've not heard from them as yet.  Maybe I chould call.  Anyway, I found out that Brodak doesn’t have any of the 2-1/4” wheels so I’ll need to reorder from somewhere or open the wheel well another ½” in diameter, a thought that does not tickle my fancy at all.  I spent a few minutes fabricating, painting and mounting a headrest because I realized that I forgot to do it earlier.  I used some Testors Paint to outline the canopy frame.  I came back in the workshop after giving the paint time to dry and decided to attach the canopy to the fuselage using some RC-56 adhesive.  I held the canopy in place with some fine pins while the adhesive dried overnight.  To make this look its best, I probably should get some black dye so I can dye the propeller and paint the tips yellow.

Friday, February 9, 2018
I came into the workshop and started the session by adding another coat of RC-56 adhesive to the canopy/fuselage joint as a bit of reinforcement.  I spent a few minutes updating the logs and adding a few more photos to document the build.
 
Saturday, February 10, 2018
I started the day around 0730 and by 0845, I was on my way to the flying field.  Both George, Larry and I brought our BEARCATS and sat them on the flight line for a "Show and Tell" session with the rest of the gang.  It was exciting to see and most notably, all three planes were different in power plant configuration, color/tone and mine was the only one with a pilot.  George painted his and it was much lighter in tone than the other two.  While the planes looked nice, they really do need the graphics.  None of us opted to test run the engines besides neither Larry nor I brought the transmitters to test operate the throttles and retracts.  When I returned home, I spent a few minutes reattaching the throttle pushrod for the BEARCAT, then I hung it on the rack until I receive the smaller wheels I ordered.

Wednesday, February 14, 2018
Happy Valentines Day!  I received and mounted the Robart 2-1/4” wheels on the BEARCAT that arrived yesterday.  In one way, it is so much nicer to see all the clearance for the wheels in the wheel wells but at the same time, I’m wondering if there will be general success regarding the likely ground clearance since we’re flying off grass.  I hope it’s sufficient height.  Otherwise, I’ll be back on the work bench resorting to the Dremel sander!  I hung it back on the rack in preparation for the initial engine runs and test flight.

Saturday, February 17, 2018
On Friday, I received the proposal for the BEARCAT markings from a fellow and was completely shocked at his price.  I spoke/texted and or emailed the various members of the club who have or are building one of these planes and to the man, they all said "No" to the proposed price per set.  Granted they all understood these were custom set which required special care and setup but this was an no -go across the board.  He wanted $$50 plus postage for each of (7) sets.  Needless to say, I had to cancelled the order.

Saturday, February 24, 2018
Around 0830 or so I headed for the flying field and spoke with the guys about the Bearcat markings all of whom rejected the idea of $50 per set.  When I returned home, I made sure I sent him another email cancelling the request.  After another brief "show and Tell", I loaded the batteries in the wing of my BEARCAT since Larry and George were cajoled into and decided to break the ice and fly their planes even though we didn’t have the decal markings.  Larry flew first then George and both flew very nice.  Larry demonstrated his throttle control and his retracts which worked flawlessly.  After a bit of engine adjusting, I flew my BEARCAT.  It lifted off very nicely and generally speaking, the throttle function worked just fine.  I didn’t try the retracts because of the bad gear in the outboard wing retract which if I had tucked it up, it might not have come down.  Nevertheless, it did fly and it flew very nicely.  Unfortunately, I forgot to tighten the wheel axles and as soon as I touched down both wheels turned inboard and stopped the plane thus nosing up like the old WWII movie of the carrier deck landing.  Thankfully there was no damage other than to my pride.  When I returned home, I cleaned it up then hung it on the rack until I can replace the retract unit.


Offline Avaiojet

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Re: Brodak F-8F Bearcat
« Reply #15 on: February 28, 2018, 06:28:20 AM »
Jim,

I cannot believe how fast you put this Bearcat together. Outstanding.

Thanks for the plan set you mailed me so I could produce that custom Blue Angels set for the Brodak Bearcat.

Today I will try to get to the PO and mail your plans back. I will also mail that custom graphics set for your Bearcat as I mentioned early on.

Seeing you have flown the model, now you have to really make sure the surfaces where graphics are being placed is absolutely clean. Really clean.

I'm looking forward to seeing your Bearcat sporting CFC Graphics.

You did a great job with that model.

Charles
« Last Edit: February 28, 2018, 01:51:50 PM by Avaiojet »
Trump Derangement Syndrome. TDS. 
Avaiojet Derangement Syndrome. ADS.
Amazing how ignorance can get in the way of the learning process.
If you're Trolled, you know you're doing something right.  Alpha Mike Foxtrot. "No one has ever made a difference by being like everyone else."  Marcus Cordeiro, The "Mark of Excellence," you will not be forgotten. "No amount of evidence will ever persuade an idiot."- Mark Twain. I look at the Forum as a place to contribute and make friends, some view it as a Realm where they could be King.   Proverb 11.9  "With his mouth the Godless destroys his neighbor..."  "Perhaps the greatest challenge in modeling is to build a competitive control line stunter that looks like a real airplane." David McCellan, 1980.

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #16 on: February 28, 2018, 11:47:23 AM »
 :)  Thank you!  It wasn't exactly the easiest build and modifying the fuselage for throttle control as well as the wing for the retracts were interesting, challenging modifications.  The next time I fly it, I hope to get some video footage.

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #17 on: March 22, 2018, 11:03:14 AM »
Well, folks this is close to the conclusion of the build log for this particular project.  Believe me, it has been a wonderfully satisfying project that I would recommend to anyone with a mind to pursue.  Back on Friday, March 2, 2018, I decided to replace the bad outboard retract unit in the Bearcat since the new set I ordered arrived a couple of days before.  I had to carefully cut out the balsa that covered the recessed retract unit then tested the unit again.  I was surprised as it functioned just fine, so as a test I measured and added a couple of pieces of 1/8" plywood to raise the height of the mounting beams flush with the wing surface.  With that done, I tested the setup a number of times and found there were no problems with the unit cycling up and down.  So, I did the same thing with the inboard retract unit mounting it flush with the wing surface.

Over the past couple of weeks, I'd been in discussion with our host, Mr. Charles of CFC Graphics, regarding reproduction of the graphics for this variant of the Brodak Bearcat with the understanding that we would need a total of seven sets.  On Wednesday, March 21, 2018, I began the day by separating the sets of Bearcat markings I received a few days ago for distribution to the various club members who are building Blue Angel Bearcats also.  I decided to apply my set.  I have to admit the markings for the bottom wing look good but the tail numbers and the “Blue Angel” insignia seem just a bit too large, but I’ll have to wait until they are all applied before final judgement.  Unfortunately, I messed up and lost one of the “dots” between the U and S on the left side of the plane so I wrote to the Mr. Charles with a request to send me a "dot" one as soon as possible.  I continued until all the marking were in place and I took a couple of photos for documentation.  All in all, Mr. Charles did a really fine job and all who have seen the plane in it's finished state have had very positive comments regarding the quality of the graphics.  My hat's off to you Mr. Charles  H^^!!
    
« Last Edit: March 22, 2018, 03:21:59 PM by Jim Carter »

Offline Glenn (Gravitywell) Reach

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Re: Brodak F-8F Bearcat
« Reply #18 on: March 22, 2018, 11:38:30 AM »
This build log aint over til the last dot is on! n~  I love your build logs.  Lots and lots of great ideas and useful information.  Start your next project soon! H^^
Glenn Reach
Westlock, Alberta
gravitywell2011 @ gmail . com

Offline Jim Carter

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Re: Brodak F-8F Bearcat
« Reply #19 on: March 23, 2018, 09:36:27 AM »
This build log aint over til the last dot is on! n~  I love your build logs.  Lots and lots of great ideas and useful information.  Start your next project soon! H^^
Thanks Glenn!  I appreciate your kind words.  Yesterday I was informed that I will be receiving the "last dot"  #^!!  I suppose my next entry will occur when we get the currently finished planes on the ramp for a photo op and flight session.  As for my next project .... I'm considering a scratch build of a Cessna T-50 Bobcat but then who knows .... there's so many that "tickle my fancy"  LL~ LL~


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