.074 powered "FORCE"
#1
.074 powered "FORCE"
Howdy Gang...got a bug up my tailpipe last night to build a Mike Pratt designed FORCE... but for Norvel .074 power instead of a .40.
I framed the wing..33 inch span x 6 inch chord x 1 1/8 inch thick...measurements don't include flaps yet.
Should I bother with flaps...? I'm leaning towards elevator only.
The Norvel turns a 7x3 prop about 17,000 rpm.
What would be a good line length or lap time to shoot for...?
This plane should turn out pretty light [relative term I know]..but it won't have any landing gear. If I end up loving this version, LG could always be added someday.
I have made provisions for adjustable leadouts, so is engine offset and right rudder needed in 2011-2012...or can a model like this be taught to keep the lines tight with leadout rake and wingtip weight only...?
I framed the wing..33 inch span x 6 inch chord x 1 1/8 inch thick...measurements don't include flaps yet.
Should I bother with flaps...? I'm leaning towards elevator only.
The Norvel turns a 7x3 prop about 17,000 rpm.
What would be a good line length or lap time to shoot for...?
This plane should turn out pretty light [relative term I know]..but it won't have any landing gear. If I end up loving this version, LG could always be added someday.
I have made provisions for adjustable leadouts, so is engine offset and right rudder needed in 2011-2012...or can a model like this be taught to keep the lines tight with leadout rake and wingtip weight only...?
#2
Senior Member
RE: .074 powered
Leadout adjustment and tip weight should do the trick. Some outthrust might not hurt. I think you can fly it on .012 lines and I would start about 57 feet and cut them off as needed. For TD 09 powered Jr Flite Streak, with the airplane being turned loose at @15,000 on Cox 7 x 3.5, it took that length to make it reliably stuntable for me. On 55 ft lines, it was turning 3.8 sec laps and being herded rather than flown part of the time.
Back when we had 1/2A stunt contests, I flew my TD 049 airplanes on 42 ft 008 lines. I used a Master Airscrew 6 x 3 cut down to 5 1/2 in.
Back when we had 1/2A stunt contests, I flew my TD 049 airplanes on 42 ft 008 lines. I used a Master Airscrew 6 x 3 cut down to 5 1/2 in.
#3
RE: .074 powered
Thanks Jim.....that's great to hear that 55+ foot lines are doable. A plane this size and speed...[maybe 50 mph], will hopefully be able to get er done.
I'd like to go with Spiderline instead of steel cable.
Any thoughts about flaps...? I tried them once on a TD .049 powered plane years ago and thought they were a waste. Not enough of a hemisphere with 35 foot lines and the model was too fast to appreciate squared maneuvers.
I'd like to go with Spiderline instead of steel cable.
Any thoughts about flaps...? I tried them once on a TD .049 powered plane years ago and thought they were a waste. Not enough of a hemisphere with 35 foot lines and the model was too fast to appreciate squared maneuvers.
#4
Senior Member
RE: .074 powered
On small airplanes, I like about 10 degrees movement either way for flaps. I think more movement gives too much drag on a small airplane. I've had two Shark 15 profiles with TD 09 and flaps. The weren't as fast as the Flite Streak, and did fine on 55 ft lines. I couldn't say if they turned better than the Flite Streak. Both airplanes flew very well, and I flew them in Classic, or PAMPA Advanced, stunt contests.
#5
RE: .074 powered
That sounds like good advice, Jim.
After drawing up the sideview tonight it looks like this chosen "scale" of the original drawing might work out pretty good. I'm working from a drawing that was published in Stunt News magazine.
I'm just measuring key points on the drawing and multiplying by 3...so the wing ends up about 33" and the fuselage about 24 " long.
The original was a profile plane, but I'd rather do a built up fuselage to try to capture as much of a "Jet" look as I can.
After drawing up the sideview tonight it looks like this chosen "scale" of the original drawing might work out pretty good. I'm working from a drawing that was published in Stunt News magazine.
I'm just measuring key points on the drawing and multiplying by 3...so the wing ends up about 33" and the fuselage about 24 " long.
The original was a profile plane, but I'd rather do a built up fuselage to try to capture as much of a "Jet" look as I can.
#6
Senior Member
RE: .074 powered
Hi Combatpigg, the model that you've drawn up only has 198sq"s.
That is TOO SMALL for that engine. I suggest you redraw to over 250 sq"s
of wing area. I 'm flying a Sig Akromaster (240sq" wing area), using an
MP-JET .061cu" diesel; this model flys beautifully on 44' X .008" lines.
I'm also flying a modified Ringmaster Jr (195sq") on the same 44' lines
that is pulled very strong, approx 56mph, using a PAW .049 Deluxe diesel.
your Norvel has significantly more hp than the PAW .049. There have been
many 240-250sq" models flown with PAW .049 diesels. I'll even wager that
the 300 sq" Peacemaker would fly very well with the Norvel .074.
Good luck;
Tony
That is TOO SMALL for that engine. I suggest you redraw to over 250 sq"s
of wing area. I 'm flying a Sig Akromaster (240sq" wing area), using an
MP-JET .061cu" diesel; this model flys beautifully on 44' X .008" lines.
I'm also flying a modified Ringmaster Jr (195sq") on the same 44' lines
that is pulled very strong, approx 56mph, using a PAW .049 Deluxe diesel.
your Norvel has significantly more hp than the PAW .049. There have been
many 240-250sq" models flown with PAW .049 diesels. I'll even wager that
the 300 sq" Peacemaker would fly very well with the Norvel .074.
Good luck;
Tony
#7
Senior Member
RE: .074 powered
Hi again Combatpigg, I see my suggestion to scale your design up for more wing area is too late.
In this case I suggest you do include operating flaps, because your 195sq" model will have a heavier
wing loading, than my PAW .049 powered RING Jr. Your model will certainly fly better with 50' + lines.
Tony
In this case I suggest you do include operating flaps, because your 195sq" model will have a heavier
wing loading, than my PAW .049 powered RING Jr. Your model will certainly fly better with 50' + lines.
Tony
#8
RE: .074 powered
Thanks for your replys Tony.
I would like to see those planes of your's in action. I've never seen the PAW or MPJ .049 diesels.
This plane with a little bit of "craft work" involved to make a cowl and subsequent paint on the fuselage could end up making it a little bit heavy.
I did do something in the interests of lightness and ran a 1/8" aluminum rod from the bellcrank to the elevator.
I would like to see those planes of your's in action. I've never seen the PAW or MPJ .049 diesels.
This plane with a little bit of "craft work" involved to make a cowl and subsequent paint on the fuselage could end up making it a little bit heavy.
I did do something in the interests of lightness and ran a 1/8" aluminum rod from the bellcrank to the elevator.
#10
RE: .074 powered
Hey, CPigg...
Pretty looking work!
Is your airfoil the same as on the page plans? Photo makes it look thinner, and high point further back... Have you timed the engine's fuel consumption on the bench at a likely sounding RPM? That RC firewall mount should leave you space behind bulkhead #1 for a reasonable tank capacity - just want to make sure you'll have enough juice to get the pattern in...
Modern .049 (.8cc), .061 (1.0cc) and .074 (1.2cc) engines have enormous power! Oh, well, you can (almost) always go to a slower RPM OR a flatter pitch prop to tame things.
Keep us advised?
Pretty looking work!
Is your airfoil the same as on the page plans? Photo makes it look thinner, and high point further back... Have you timed the engine's fuel consumption on the bench at a likely sounding RPM? That RC firewall mount should leave you space behind bulkhead #1 for a reasonable tank capacity - just want to make sure you'll have enough juice to get the pattern in...
Modern .049 (.8cc), .061 (1.0cc) and .074 (1.2cc) engines have enormous power! Oh, well, you can (almost) always go to a slower RPM OR a flatter pitch prop to tame things.
Keep us advised?
#12
RE: .074 powered
Howdy Lou....
I just eyeballed the airfoil. I've found that the smaller you go in size and weight [at least with RC planes]..the airfoils become less critical. I've never spent any time to speak of with control line stunters this small, though.
Until I see this thing fly, my thinking is that "speed is my friend".......then I'll have something to go by if it ends up being too fast to do a recognizable pattern with.
Might have to take some pitch out of a MAS 7x3 prop...?
The tank is a Hayes 2 ouncer, which is the most trouble free I've found in this size. It better be, because it's built into the plane now..!
Cutaway, after seeing this plane all framed up...it wouldn't look bad with more wing..maybe double or triple tapered....somewhat sportier looking. As it sits now it might fly more like a combat plane with a hot .09 diesel..?
I'll know better after seeing this thing fly whether I got it right or not. I'm hoping for a steady pulling plane that can keep me from biting my fingernails when I go for some overhead maneuvers.
After doing a little bit of snooping around I've decided to use thinned white glue and silkspan to cover the fuselage.
I've never tried thinned white glue before..only dope or polyurethane.
Then shoot it with silver Klasskote epoxy paint. The wing ought to be OK with silver monokote. Finding the "right" silver monokote is the trick. One variant shrinks nicely and is easy to work with...the other [aluminum.IIRC.?] is a *****.
Trying for a military look, it won't matter so much if it ends up a little bit "rough"....
I just eyeballed the airfoil. I've found that the smaller you go in size and weight [at least with RC planes]..the airfoils become less critical. I've never spent any time to speak of with control line stunters this small, though.
Until I see this thing fly, my thinking is that "speed is my friend".......then I'll have something to go by if it ends up being too fast to do a recognizable pattern with.
Might have to take some pitch out of a MAS 7x3 prop...?
The tank is a Hayes 2 ouncer, which is the most trouble free I've found in this size. It better be, because it's built into the plane now..!
Cutaway, after seeing this plane all framed up...it wouldn't look bad with more wing..maybe double or triple tapered....somewhat sportier looking. As it sits now it might fly more like a combat plane with a hot .09 diesel..?
I'll know better after seeing this thing fly whether I got it right or not. I'm hoping for a steady pulling plane that can keep me from biting my fingernails when I go for some overhead maneuvers.
After doing a little bit of snooping around I've decided to use thinned white glue and silkspan to cover the fuselage.
I've never tried thinned white glue before..only dope or polyurethane.
Then shoot it with silver Klasskote epoxy paint. The wing ought to be OK with silver monokote. Finding the "right" silver monokote is the trick. One variant shrinks nicely and is easy to work with...the other [aluminum.IIRC.?] is a *****.
Trying for a military look, it won't matter so much if it ends up a little bit "rough"....
#13
Senior Member
RE: .074 powered
ORIGINAL: combatpigg
Howdy Lou....
I just eyeballed the airfoil. I've found that the smaller you go in size and weight [at least with RC planes]..the airfoils become less critical. I've never spent any time to speak of with control line stunters this small, though.
Until I see this thing fly, my thinking is that ''speed is my friend''.......then I'll have something to go by if it ends up being too fast to do a recognizable pattern with.
Might have to take some pitch out of a MAS 7x3 prop...?
The tank is a Hayes 2 ouncer, which is the most trouble free I've found in this size. It better be, because it's built into the plane now..!
Cutaway, after seeing this plane all framed up...it wouldn't look bad with more wing..maybe double or triple tapered....somewhat sportier looking. As it sits now it might fly more like a combat plane with a hot .09 diesel..?
I'll know better after seeing this thing fly whether I got it right or not. I'm hoping for a steady pulling plane that can keep me from biting my fingernails when I go for some overhead maneuvers.
After doing a little bit of snooping around I've decided to use thinned white glue and silkspan to cover the fuselage.
I've never tried thinned white glue before..only dope or polyurethane.
Then shoot it with silver Klasskote epoxy paint. The wing ought to be OK with silver monokote. Finding the ''right'' silver monokote is the trick. One variant shrinks nicely and is easy to work with...the other [aluminum.IIRC.?] is a *****.
Trying for a military look, it won't matter so much if it ends up a little bit ''rough''....
Howdy Lou....
I just eyeballed the airfoil. I've found that the smaller you go in size and weight [at least with RC planes]..the airfoils become less critical. I've never spent any time to speak of with control line stunters this small, though.
Until I see this thing fly, my thinking is that ''speed is my friend''.......then I'll have something to go by if it ends up being too fast to do a recognizable pattern with.
Might have to take some pitch out of a MAS 7x3 prop...?
The tank is a Hayes 2 ouncer, which is the most trouble free I've found in this size. It better be, because it's built into the plane now..!
Cutaway, after seeing this plane all framed up...it wouldn't look bad with more wing..maybe double or triple tapered....somewhat sportier looking. As it sits now it might fly more like a combat plane with a hot .09 diesel..?
I'll know better after seeing this thing fly whether I got it right or not. I'm hoping for a steady pulling plane that can keep me from biting my fingernails when I go for some overhead maneuvers.
After doing a little bit of snooping around I've decided to use thinned white glue and silkspan to cover the fuselage.
I've never tried thinned white glue before..only dope or polyurethane.
Then shoot it with silver Klasskote epoxy paint. The wing ought to be OK with silver monokote. Finding the ''right'' silver monokote is the trick. One variant shrinks nicely and is easy to work with...the other [aluminum.IIRC.?] is a *****.
Trying for a military look, it won't matter so much if it ends up a little bit ''rough''....
Hi Combatpigg, I guess there are several of us interested in this project. You can control lap speed(not model speed) with flying line length. Going to a lower
pitch will buy you higher rpms, resulting in lower fuel range. If you stay with a 3" pitch, you might give increasing the prop diameter a try.
I'm afraid your model is going to weigh 13+ ozs; at 198sq"s this model will not fly like a combat ship. Prior generation TD .049 Combat designs were usually 190-200+ sq"s,
and they weighed 4.5-6ozs resulting in very low wingloading. This is why I suggest you use operating flaps. I think this model will fly a decent stunt pattern, even at 13+ ozs.
John Wright used to fly a PDQ Flying Clown" in OTS powered by a .25(Fox??). His "Flying Clown" has 200sq"s wing area, but he used long enough lines that maximized it's ability
to fly the OTS stunt pattern; and I'm pretty sure that 200sq"s was carrying close to 20ozs. Yes, keep us abreast with your experiences, Because I do wish you the Best!
Tony
#14
RE: .074 powered
Paw....Do you do any flying with Rich Lopez...?
Such a great guy he is. I started out in 1/2A combat flying the SlySir which I think was either his design, or Steve Hills'.
Then switched to Larry Driskill's HalfLite.
6 ozs would have been a good weight for a foamie.....IIRC.
A 4.5 oz plane with 200 square inches must be the one you save for the final "Kamikazi" round...?
Such a great guy he is. I started out in 1/2A combat flying the SlySir which I think was either his design, or Steve Hills'.
Then switched to Larry Driskill's HalfLite.
6 ozs would have been a good weight for a foamie.....IIRC.
A 4.5 oz plane with 200 square inches must be the one you save for the final "Kamikazi" round...?
#15
Senior Member
RE: .074 powered
ORIGINAL: combatpigg
Paw....Do you do any flying with Rich Lopez...?
Such a great guy he is. I started out in 1/2A combat flying the SlySir which I think was either his design, or Steve Hills'.
Then switched to Larry Driskill's HalfLite.
6 ozs would have been a good weight for a foamie.....IIRC.
A 4.5 oz plane with 200 square inches must be the one you save for the final ''Kamikazi'' round...?
Paw....Do you do any flying with Rich Lopez...?
Such a great guy he is. I started out in 1/2A combat flying the SlySir which I think was either his design, or Steve Hills'.
Then switched to Larry Driskill's HalfLite.
6 ozs would have been a good weight for a foamie.....IIRC.
A 4.5 oz plane with 200 square inches must be the one you save for the final ''Kamikazi'' round...?
I flew with those guys a long time ago. I started with the Sly-Sirs and then flew Barry Baxter's 1/2A Phoenix.
The 200 sq" Phoenix weighed 4.5-4.6 ozs, and were faster and turned better than the Sly-Sirs, per given
engine. I then gave high aspect wing models a try and I liked the awesome turning characteristic of the 1/2A
Monoboom. the original Monoboom was a bit small at 164sq"s, so I enlarged the design and thinned the airfoil,
building the design to 195 sq"s and using a foam leading edge instead of the "D" tube. My 195 sq" Monoboom weighed
4.9-5.1 ozs ready to fly. It was a bit faster and turned better than the 164sq" Monoboom.
Barry later evolved the Phoenix into the better flying "Doom Bat". Barry's "Phoenix" and "Doom Bat" were foam LE
built up flying wing with balanced elevator designs.
Tony
#16
RE: .074 powered
I remember the fast combat Monoboom. I think it was Greg Hill in the late 1980s who showed up here with these wooden masterpieces that were designed / built by a guy named Hoffeldt...?
They were tremendous flyers, but were too fragile for combat.
A local guy [Dick Salter] campaigned a similar 1/2A version he called the Fantail, but they were just too labor intensive for "The Show". If that design used Soviet style framework, it would have made some difference for survivability.
Even though I loved 1/2A combat, it never lived up to it's potential in my mind. Most of the local contests boiled down to matches marred with no starts, and fatal mid airs after very little jousting.
They were tremendous flyers, but were too fragile for combat.
A local guy [Dick Salter] campaigned a similar 1/2A version he called the Fantail, but they were just too labor intensive for "The Show". If that design used Soviet style framework, it would have made some difference for survivability.
Even though I loved 1/2A combat, it never lived up to it's potential in my mind. Most of the local contests boiled down to matches marred with no starts, and fatal mid airs after very little jousting.
#17
RE: .074 powered
Here's a progress report.
The fuselage has been covered with silkspan and white glue. It worked out pretty well for a first attempt. If weight permits, I might put a 2nd layer on the belly [that was made from blue foam].
The cowl is under developement. I started with a blue foam plug, then undercut the plug and surrounding area where the cowl overlaps the nose of the plane. This was done so that a strong buildup of cloth over the plug would come out "flush" with the rest of the plane. It is painstaking to cut out swatches of 6 oz cloth, then mist them with 3M77, then rub medium CA into each piece...one at a time...then knock down the fuzz and repeat...but eventually you get there without using any epoxy.
The foam plug gets covered with clear packing tape before the cloth is applied.
Right now I'm blending the edges of the cowl to the rest of the plane with Bondo..so there are still some hours left before this thing is ready for paint.
The fuselage has been covered with silkspan and white glue. It worked out pretty well for a first attempt. If weight permits, I might put a 2nd layer on the belly [that was made from blue foam].
The cowl is under developement. I started with a blue foam plug, then undercut the plug and surrounding area where the cowl overlaps the nose of the plane. This was done so that a strong buildup of cloth over the plug would come out "flush" with the rest of the plane. It is painstaking to cut out swatches of 6 oz cloth, then mist them with 3M77, then rub medium CA into each piece...one at a time...then knock down the fuzz and repeat...but eventually you get there without using any epoxy.
The foam plug gets covered with clear packing tape before the cloth is applied.
Right now I'm blending the edges of the cowl to the rest of the plane with Bondo..so there are still some hours left before this thing is ready for paint.
#18
RE: .074 powered
Some hours later the cowl is being fitted to the engine. It's time to make a little venturi and a remote needle..plus a way to fuel the plane.
In the past I've been able to fuel cowled set ups through the muffler line with the nose of the model pointed down. If it's done with a little bit of care, it works OK.
I figure the needle can mount near the firewall above the muffler, so I would only have to expand the cutout in the cowl to accomodate the needle.
As it sits, the canopy isn't very ding proof. I'm going to spackle some divits for the last time and then glass it. I should do the same with the belly, too.
In the past I've been able to fuel cowled set ups through the muffler line with the nose of the model pointed down. If it's done with a little bit of care, it works OK.
I figure the needle can mount near the firewall above the muffler, so I would only have to expand the cutout in the cowl to accomodate the needle.
As it sits, the canopy isn't very ding proof. I'm going to spackle some divits for the last time and then glass it. I should do the same with the belly, too.
#19
RE: .074 powered
With all of the wrestling around to get the cowl details done I've managed to dent the foam canopy.
Should have bit the bullet and ordered some light balsa block.
I don't want to add a bunch of weight with FG, epoxy, bondo, etc...this plane is just a trial version I'll bet...there will probably be a 2nd version with some tweaks like a longer tail and more wingspan.
So, this one will get a down & dirty finish, then go fly it.
Should have bit the bullet and ordered some light balsa block.
I don't want to add a bunch of weight with FG, epoxy, bondo, etc...this plane is just a trial version I'll bet...there will probably be a 2nd version with some tweaks like a longer tail and more wingspan.
So, this one will get a down & dirty finish, then go fly it.
#20
RE: .074 powered
Here it is after......
Filling the dents in the foam canopy with spackle
Applying a 2nd layer of silkspan and white glue over the canopy and belly
Applying spray can primer / filler and spot putty
Shooting it with Duplicolor rattlecan aluminum
Covering with monokote aluminum
What is the rule of thumb for lateral CG..?
I'll be using Spiderline, most likely 100 foot total.
Years ago I heard of some method that took into consideration the weight of the lines to make at least a rough guess at how much tip weight to add.
As far as fore and aft CG is concerned, I assume that 25% is routine for C/L Stunt as a starting point...?
Filling the dents in the foam canopy with spackle
Applying a 2nd layer of silkspan and white glue over the canopy and belly
Applying spray can primer / filler and spot putty
Shooting it with Duplicolor rattlecan aluminum
Covering with monokote aluminum
What is the rule of thumb for lateral CG..?
I'll be using Spiderline, most likely 100 foot total.
Years ago I heard of some method that took into consideration the weight of the lines to make at least a rough guess at how much tip weight to add.
As far as fore and aft CG is concerned, I assume that 25% is routine for C/L Stunt as a starting point...?
#21
RE: .074 powered
That is really looking sharp!
I have not flown a 1/2a c/l in over 30 years (or any other size c/l for that matter). I think I used to glue a nickle to the outboard tip. I have no clue if that was right or wrong.But worked at the time, but I dont think I flew on much mare than 30-35 foot lines.
It looks like yor leadout guid is adjustable, nicely done.
I have not flown a 1/2a c/l in over 30 years (or any other size c/l for that matter). I think I used to glue a nickle to the outboard tip. I have no clue if that was right or wrong.But worked at the time, but I dont think I flew on much mare than 30-35 foot lines.
It looks like yor leadout guid is adjustable, nicely done.
#22
RE: .074 powered
Thanks for the compliment...[8D]
I wonder if Abe Lincoln would be honored to know how many times his likeness has had rides on the outboard wing of C/L aircraft...?
Once I find a leadout position that works, I'll glue that block in place, then cover up the gaping hole.
I wonder if Abe Lincoln would be honored to know how many times his likeness has had rides on the outboard wing of C/L aircraft...?
Once I find a leadout position that works, I'll glue that block in place, then cover up the gaping hole.
#23
RE: .074 powered
Here it is almost finished.
It has KlassKote clear over auto store touch up paint. I sanded the aluminum touch up paint with 400 before shooting the clear and it left an "interesting" look in the final product.
What there is left to do is balance the plane, [make a control horn out of steel], make up a set of lines out of Spiderline and modify my launching ramp for this little plane.
It has KlassKote clear over auto store touch up paint. I sanded the aluminum touch up paint with 400 before shooting the clear and it left an "interesting" look in the final product.
What there is left to do is balance the plane, [make a control horn out of steel], make up a set of lines out of Spiderline and modify my launching ramp for this little plane.
#24
Senior Member
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Location: Lake Worth, FL
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RE: .074 powered
ORIGINAL: combatpigg
...this plane is just a trial version I'll bet...there will probably be a 2nd version with some tweaks like a longer tail and more wingspan.
...this plane is just a trial version I'll bet...there will probably be a 2nd version with some tweaks like a longer tail and more wingspan.