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Indoor Free Flight Forum => Peanut Scale => Topic started by: FLYACE1946 on March 08, 2016, 01:42:13 PM



Title: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on March 08, 2016, 01:42:13 PM
Has anyone built this peanut yet ? Got any Advice on the proposed project ? Please share ok?

Thanks in advance.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Bredehoft on March 08, 2016, 02:57:53 PM
Gene Smith in Oklahoma flies - and wins with - a Peanut Tigercat - can't say for sure it is built from Dick Howard's plans.

--george


Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on March 08, 2016, 03:02:56 PM
Yes he does and it's from the plan done by Dick Howard.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on September 19, 2019, 11:10:37 AM
I just started one of these from the plans in the Plan Gallery.  The plans show a unique method of fuselage construction.  I gave up on that and made it a half shell, the former cross-sections are shown on the side view.  Was there a magazine article on this, or maybe a newsletter?  I saw Mike Kelly's Tigercat at the NonNats - very pretty airplane.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: tom arnold on September 19, 2019, 03:20:51 PM
There was no magazine article on Dick's Tigercat as the plan was drawn up for the Cactus  Sqdn newsletter. The key to making this fly, I have been told, is the prop and motor combo and what it is, I don't know. Gene Smith would have the secret, though.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: mescal1 on September 19, 2019, 03:32:57 PM
I'll dig around for the newsletter.  I don't remember an article but there may be a short note.  Daughter has volleyball tonight but I'll try to post what I find tomorrow.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on September 20, 2019, 07:21:56 PM
Thanks for the help. I still want to build this one. Any help would be appreciated. Since the plan also appeared in the FAC National Newsletter package there could be many people with this plan already interested. A short note could be very helpful.

I hope your daughters team won the game.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: mescal1 on September 20, 2019, 09:57:41 PM
Thanks, They did ;D

The plan appeared in the Nov/Dec 1996 issue of the Cactus Squadron News.  I'll just type out everything.

Building the F7F-1 Grumman Tigercat Peanut
By Dr. Gene Smith

The model was built according to the plans using the crucifix style of construction shown on the plans.  Use 1/20 sq. sticks
and 1/32 sheet to keep the construction light.  The engine nacelles were built using 1/20 sq. sticks and 1/32 sheet bulkheads.
The model weighed 11.4 grams complete with props and with no ballast added for balancing.  Props were constructed using
cottage cheese container blades cut from the container at a standard 15 degree angle to the vertical.  Don't forget to cut 3 blades
for ccw rotation and 3 for cw rotation.  Prop rotation is ccw on the left and cw on the right as viewed from the front of the model.
Motors were .100 by 14 inches in length and no need to braid as the rubber all ends up on the CG with the short nacelles.  Normal
ramp freewheelers were used on the hubs.  The finish was thinned Floquill and Dope with painted Mica film trim used for the insignias
and markings.  Set in about 3 degree Down thrust in each nacelle and adjust the down thrust on either nacelle to the the power
pattern straight.  Motors will take about 1200 turns with 1600 maximum for flights in the 40 to 50 second range.  I have had one
thermal flight at the FAC NATS that was  timed at 3 min 20 sec.  What a Thrill!  Love this hobby!!!  Have at it peanuteers.  The twin
challenge is waiting.

I've seen Gene's model and it flies great.  The crucifix method of building is in the Sept 1985 Model Builder Fernando Ramos article.
Good luck!  (post pictures!)


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on September 22, 2019, 03:34:21 PM
Thanks for posting the text.  I would very much like to read about the crucifix construction. I got about halfway through the fuselage with the crucifix method but I made a big mistake - I thought the angled 1/20 sticks were sufficient to hold the stringers in the right position but it became obvious I should have added quarter-formers to round out the fuselage cross section.  I punted, and resorted to a method with which I had more experience.  Here is a shot of the fuselage and the nacelle sides.  What's in the picture weighs 1.7 grams.  I'll have to be careful.  But I'm pleased with how it's turned out so far, it is a very pretty airplane, so just getting reasonably close to scale looks pretty good.  Not a straight stringer on the thing, but the curves look real nice.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: mescal1 on September 22, 2019, 04:15:13 PM
Looks great!  Here's some motivation. 
https://www.youtube.com/watch?v=baNOKx2XZxM
Mike


Title: Re: F7f Tigercat plan by Dick Howard
Post by: MKelly on September 22, 2019, 04:49:07 PM
That's looking quite nice Duncan!  Have you picked colors for it yet?

Cheers,

Mike


Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on September 23, 2019, 10:00:33 PM
Sure nice to see the information. Especially the Gene Smith sequence. Gene is very helpful.  Chop that balsa as Joe Joseph used to say.

Thanks everybody.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on October 01, 2019, 10:04:34 PM
Some can build a great looking model of a homely airplane, but I do better with really pretty ones.  I just had to tack the parts together to see.  So far, so good.  

Not certain but I'm leaning towards the standard blue color scheme for the F7F-1.  That's all I have found good documentation for so far, and it will be far easier to do with tissue.  I'm trying to be as weight conscious as possible. The total is 5.1 grams so far and I have prop blocks, props, canopy, covering and markings yet to do.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Crabby on October 02, 2019, 09:03:42 AM
Great going Duncan are you gonna try it out at the compound?


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on October 02, 2019, 03:49:11 PM
Sure hope to.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on November 07, 2019, 08:08:48 AM
Well it flies, and better than I hoped.  Really, right off the board - all I have done is tweak a little left rudder to open up the right turn under power.  It even glides pretty good as long as neither motor bunches up in the back.  If that happens the prop starts to freewheel while the other is still under power, and the plane spirals in.  Have to figure out some tiny floating pegs.

The props are 4 inches in diameter, 5 inches in pitch.  Cut from a small sour cream plastic container, angled around 25 degrees.  Counter rotating with the tips moving outboard on top.  There is a close-up of a front end, with the Nason clutch.  I'm using a 12 inch loop of 1/16, braided.  Have to make left and right-handed motors  :)

I haven't got it to Palm Bay yet, but flew it at the Kudzu Classic in Raeford - longest flight was 45 seconds.  Really fun to watch, I just hope this isn't beginners luck!


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Bredehoft on November 07, 2019, 08:19:21 AM
Well done, Duncan!  45 seconds is great. 

--george


Title: Re: F7f Tigercat plan by Dick Howard
Post by: MKelly on November 07, 2019, 08:22:39 AM
That's a beauty Duncan - congrats on the successful flights.  If you find a working solution to the bunching please share it - I'm struggling with that on both my Skyrocket and the Diels Tigercat, even with tube-over-tube at the rear pegs.

Mike


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Bredehoft on November 07, 2019, 09:59:59 AM
If you find a working solution to the bunching please share it ...

shorter motors ;-)

I help where I can...

--george


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Crabby on November 07, 2019, 11:21:18 AM
Good am Duncan and a beauty of a job. I like Dick Howard plans they are easy on the eyes and compelling. I have to summon the mojo to finish the Piper Navajo. Of course building a twin means making a winding stooge and a launching apparatus. How did you tackle those items?


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on November 07, 2019, 12:35:07 PM
Hi Crabby,
The stooge was pretty simple - I got the idea from Tom Hallman's solution for his Mig Dis on you tube.  It is a little custom stooge from 1/8" craft plywood that connects to my regular stooge.  the back of the plywood base fits in the bottom of the big stooge, where I drilled holes so a wire stuck through the big stooge retains the little one.  I glued a cross piece of ply so the wire holds it down and in.

The little stooge just has ply uprights for each nacelle and a little cushion of foam.  I can wind one motor and just let the prop hit the front of the stooge, that is enough to hold it while I wind the other motor.  To remove it I just hold the plane by the nose and let the props hit my hand, pull out the wire retainers and it's ready to go.

It wouldn't be hard to make the uprights movable to use the little stooge for more than one plane.  Next time...


Title: Re: F7f Tigercat plan by Dick Howard
Post by: MKelly on November 07, 2019, 02:31:03 PM
A dedicated twin stooge is nice but not required - I wind my Tigercat and Skyrocket on my (ugly) single stooge.  Pin one nacelle, wind, restrain the wound prop with a remove-before-flight pin, swap to the other nacelle, wind that one (see pics).  Allen is steadying the model in the second picture, but that's a convenience rather than a necessity.

Just don't forget and start winding #2 without pinning that nacelle in the stooge...

Mike


Title: Re: F7f Tigercat plan by Dick Howard
Post by: tom arnold on November 07, 2019, 03:55:46 PM
Same here. A single stooge works fine. oops can't figure out how to rotate the photo.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on November 07, 2019, 04:30:43 PM
Well you can't argue with success.  I was thinking there would be too much weight or wind load on the nacelle peg with the plane hanging on the end, but you guys are certainly making it work.  Not the first time I've overthought things. Thanks.

Mike, on motor bunching, I'm trying something I heard from Stew Myers via Dan Driscoll:  You can take a plastic drinking straw, hold the end up to a match and watch it curl back on itself to make half a little bobbin.  Cut the straw to the right length (practice) so when you melt the other end you end up with a cute little bobbin.

Photos show the first melted end on the straw, after the second melt, the bobbin in the motor, and the bobbin loaded on a little stuffing stick.  That is a single loop of 1/16 rubber for scale.  The straw is a loose fit on a 1/8" aluminum peg.

We'll see how it works.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: OZPAF on November 07, 2019, 06:43:31 PM
What a neat idea Duncan.

John


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Pat D on November 08, 2019, 09:37:31 AM
here here !

that really is very clever

Pat !


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Crabby on November 08, 2019, 10:14:11 AM
If you told me that was what you were gonna try I'd be a doubting Thomas. Now I gotta start feverishly collecting drinking straws before they are outlawed.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on November 20, 2019, 09:18:27 PM
Got some flights in at Palm Bay this morning.  Tricky to launch one-handed but the plane handled it just fine.  The turn widens as the power burst winds down.  Still ends up gliding either way depending on which prop freewheels better.  The little plastic bobbins work ok, but there is still some random bunching.

https://www.youtube.com/watch?v=Z9_ir3GG1i0


Title: Re: F7f Tigercat plan by Dick Howard
Post by: MKelly on November 20, 2019, 10:32:37 PM
Great flight Duncan!  I need to try some of those straw bobbins...

Mike


Title: Re: F7f Tigercat plan by Dick Howard
Post by: OZPAF on November 21, 2019, 01:39:01 AM
Very impressive Duncan!
John


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Walt on November 21, 2019, 10:32:13 PM
Duncan- beautiful flights on the twin and Jimmy Allen!  Thanks for posting the videos. Great work!
Wally


Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on November 24, 2019, 06:37:55 PM
That is a great flying location. Sure would like to make it down there sometime. My old friend George Perryman went there often. Usually right after family get togethers around Christmas time. Sure do miss talking to him.

Allen


Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on June 20, 2020, 04:45:22 PM
I want to do a Tigercat but first up will be my Piper Navajo . Gotta do that first.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on July 09, 2020, 07:20:17 PM
I just have to ask this question: On the plan for the F7F-1 Tigercat Dick shows two sticks that are hatched. Is this done on each side of the fuselage? I know to use the 1/20 th size sticks and 1/32 sheet balsa for the bulkheads. I need to see (if at all possible)what the crucifix style looks like for this project. I must be over thinking it somehow.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Duncan McBride on July 10, 2020, 12:26:05 PM
I couldn't figure it out either.  I ended up cutting some regular bulkheads and putting on stringers.


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Indoorflyer on July 10, 2020, 12:27:06 PM
Those cross hatched strips go down the center of the fuselage--they form the central keel that captures the cross member of each bulkhead/station. Earlier in this topic, the Sep 1985 Model BUilder magazine was mentioned as a ref for this type of fuselage construction.

In the view of the bulkhead/former, you can see the two beams in the center, one above the other

EDIT: here's my take on it:



Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on July 10, 2020, 01:12:35 PM
Thank You that is just what I needed to see. Thanks a bunch. Indoorflyer did you draw this up yourself or was it in the Model Builder magazine column?


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Indoorflyer on July 10, 2020, 01:46:12 PM
Hi Flyace--I just made a very quick sketch on a scratch pad---Once you see the keel  the "Aha" moment strikes!  The keel with its "arms" forms the cruciform spine.   It's a very interesting design, should be pretty rigid, since the bulkheads have a triangular skeleton, and the oval fuselage cross section is created with thin sheet pieces attached to the legs of the triangles. (Don't know why my picture is rotated 90 degrees, maybe I should use my phone to crop and rotate it)

EDIT:  rotated the image in Post #35


Title: Re: F7f Tigercat plan by Dick Howard
Post by: FLYACE1946 on July 10, 2020, 06:23:29 PM
I really like the sketch you did. Helps a lot. 


Title: Re: F7f Tigercat plan by Dick Howard
Post by: Indoorflyer on July 10, 2020, 06:35:04 PM
Thanks--glad it helps folks visualize the thing.  That Tigercat is a perfect subject for a rubber FF model. Nacelles are roomy enough for decent size rubber motors.  The fuselage construction is optimized for the twin layout--it wouldn't work for a standard single engine type with the rubber going through the middle of the fuselage.  A CAD drawing of the entire fuselage would be a helpful building aid...