Daniel Kezar
Ultimate Cheap Skate
ok. do you think it would downscale well for a 2213 935kv with 20 amp esc and 9x4.5 prop running 1000 3s? 9g servo of course
ok. do you think it would downscale well for a 2213 935kv with 20 amp esc and 9x4.5 prop running 1000 3s? 9g servo of course
Tench745
Master member
The setup as is gives theoretical values of:
Thrust: 11.2oz
Stall Speed: 14.5 MPH
Max Speed: 26.7 MPH
Amp draw: 6.2A
Your setup would give you:
Thrust: 21oz
Stall Speed: 14.5 MPH
Max Speed: 36.3 MPH
Amp draw: 8.25A
I think this would work, but can't promise anything without trying it. You will most likely need to add some nose weight to get the balance correct.
If you do attempt to build this, I'm happy to answer questions and may end up building along. No promises though, I'm out of storage space.
Thrust: 11.2oz
Stall Speed: 14.5 MPH
Max Speed: 26.7 MPH
Amp draw: 6.2A
Your setup would give you:
Thrust: 21oz
Stall Speed: 14.5 MPH
Max Speed: 36.3 MPH
Amp draw: 8.25A
I think this would work, but can't promise anything without trying it. You will most likely need to add some nose weight to get the balance correct.
If you do attempt to build this, I'm happy to answer questions and may end up building along. No promises though, I'm out of storage space.
Daniel Kezar
Ultimate Cheap Skate
The setup as is gives theoretical values of:
Thrust: 11.2oz
Stall Speed: 14.5 MPH
Max Speed: 26.7 MPH
Amp draw: 6.2A
Your setup would give you:
Thrust: 21oz
Stall Speed: 14.5 MPH
Max Speed: 36.3 MPH
Amp draw: 8.25A
I think this would work, but can't promise anything without trying it. You will most likely need to add some nose weight to get the balance correct.
If you do attempt to build this, I'm happy to answer questions and may end up building along. No promises though, I'm out of storage space.
haha! thanks for the info! you should submit this plane for the card game (if you haven't already). you have all the specs!
Tench745
Master member
So, seeing as there was interest and I have a lot of free time lately, I updated the plans to address problems I had with the last model and make assembly a little more self-explanatory.
View attachment McB Jenny.pdf
View attachment McB Jenny.pdf
Daniel Kezar
Ultimate Cheap Skate
thanks! downloaded now!
Tench745
Master member
Zombie Thread!
I was going through my files and decided to tidy up my last version of the plans for Jenny, they are now included in the resources section (visable as soon as it gets approval).
https://forum.flitetest.com/index.php?resources/mcb-jn-4-jenny.270/
In putting that resource together, I also realized that I never posted the last video I made of my Jenny flying.
I was going through my files and decided to tidy up my last version of the plans for Jenny, they are now included in the resources section (visable as soon as it gets approval).
https://forum.flitetest.com/index.php?resources/mcb-jn-4-jenny.270/
In putting that resource together, I also realized that I never posted the last video I made of my Jenny flying.
Mr NCT
Site Moderator
Starting my second JN-4 (does that make it a JN-5?) based on Tench745's plans. Going with folded wings top and bottom and printed firewall, radiator and cowl/battery hatch. Made the pin on the hatch that fits in the hole on the firewall with a hole to reinforce it with a chunk of BBQ skewer for strength. Really enjoying having a 3D printer.
Tench745
Master member
In light of Flite Test releasing their Jenny XL kits, I'm going back through my plans for the Jenny, building a new version, and polishing up the plans as I find errors during construction. I've already removed a couple redundant marks on the plans and fixed an error with the wing struts/aileron area.
The biggest change for this coming version will be a foamboard turtledeck.
The biggest change for this coming version will be a foamboard turtledeck.
Tench745
Master member
Alright, things are coming along well and plans should be ready for release any day now, so here's the start of a build guide. Anyone familiar with FT plans should be familiar with most of the building techniques, so this won't be a step by step tutorial. I aim to cover the things that are a little different or may not be obvious from the plans.
I will be releasing plans with two different fuselages; one long and one short. The long fuselage is scale accurate, but will require extra nose weight and/or a concerted effort to keep weight out of the tail. (eg. white gorilla glue instead of hot glue).
The short fuselage is intended to let you build with hot glue and standard FT build techniques without pushing the CG too far aft.
Starting with the fuselage, you'll need to prep your parts. Weed out the various cavities as marked, cut bevels in control surfaces, etc.
To keep the tail as light as possible, you'll want to remove the paper from interior of the aft fuselage sides and the aft portion of the belly plate.
The cockpit openings should be transferred through to the top of the foam but not be cut out completely until after the turtledeck is installed.
Doubler plates are glued to the fuselage sides and then the fuselage can get glued up.
There are two pockets in the tail, one in the horizontal stabilizer and another in the elevator. Both of these get a BBQ skewer inserted to stiffen the stabilizer and elevator respectively.
The vertical stabilizer slots into the horizontal, then the two together slot into the rear fuselage.
The rudder and elevator pushrods should run through the slits in turtledeck former 4, cross each other underneath the turtledeck and then exit through the slits in the turtledeck. You should be able to feed the pushrod into place after attaching the turtledeck, as long as you make sure to widen the slots in former 4 beforehand. I like the stiffness of .047" (1.19mm) music wire for pushrods, especially on long sections like this. Carbon Fiber pushrods are recommended if building the long fuselage version.
Even though it is drawn as one piece, and can be installed a such, I found that cutting the turtledeck into a forward, mid, and aft section which are installed separately makes for a much easier process.
The power pod is a minimal affair, and only necessary if using an FT firewall. If you're custom cutting your own firewall you can simply make it wide enough to glue to the forward end of the doubler plates.
If using the power pod, the open side of the C faces down. When you glue the firewall on, flush the bottom edge to the bottom of the power pod sides. Wrap tape around the firewall for reinforcement, then glue the power pod in, sliding the firewall up into the wide slot in the fuselage. (Pictures are of an earlier power pod. The one in the plans has significantly more down thrust now.)
The motor wires route up through the large opening above the motor and the ESC can glue or velcro in under the forward turtledeck. The reciever snugs nicely into the forward cockpit. I found that it is easier to install the turtledeck before the cabanes are installed, then trim the cutouts for the cabanes if necessary.
The cabane struts slot into the fuselage either side of the forward cockpit. To stiffen the cabanes, push a BBQ skewer down into the fuselage at the mark, following the angle of the cabane. Mark the top of the skewer about 1/8" longer than the cabanes, cut to length, then glue onto the cabane and into the fuselage. You'll want to mostly cut out the center portion of cabane struts, but leave it in place until after the wing is installed to help hold everything square.
The landing gear strut will also get a skewer glued along the leading edge for strength. Like the wing struts, cut the center out most of the way, but leave it in place until final assembly. The landing gear struts can't be fully installed until after the lower wing is in place.
The gear itself is 3/32" piano wire bent to shape (per the template in the plans) and glued into a foam sandwich. This assembly then slots into the doubler plates, much like the FT Scout or Edge. The half of the foam sandwich notched for the landing gear wire faces the nose of the plane. The wheels are approximately 2 1/8" diameter and don't need to be particularly light. Nose weight is your friend on this plane and heavy wheels will help push your CG forward.
That's enough for tonight. More to come!
I will be releasing plans with two different fuselages; one long and one short. The long fuselage is scale accurate, but will require extra nose weight and/or a concerted effort to keep weight out of the tail. (eg. white gorilla glue instead of hot glue).
The short fuselage is intended to let you build with hot glue and standard FT build techniques without pushing the CG too far aft.
Starting with the fuselage, you'll need to prep your parts. Weed out the various cavities as marked, cut bevels in control surfaces, etc.
To keep the tail as light as possible, you'll want to remove the paper from interior of the aft fuselage sides and the aft portion of the belly plate.
The cockpit openings should be transferred through to the top of the foam but not be cut out completely until after the turtledeck is installed.
Doubler plates are glued to the fuselage sides and then the fuselage can get glued up.
There are two pockets in the tail, one in the horizontal stabilizer and another in the elevator. Both of these get a BBQ skewer inserted to stiffen the stabilizer and elevator respectively.
The vertical stabilizer slots into the horizontal, then the two together slot into the rear fuselage.
The rudder and elevator pushrods should run through the slits in turtledeck former 4, cross each other underneath the turtledeck and then exit through the slits in the turtledeck. You should be able to feed the pushrod into place after attaching the turtledeck, as long as you make sure to widen the slots in former 4 beforehand. I like the stiffness of .047" (1.19mm) music wire for pushrods, especially on long sections like this. Carbon Fiber pushrods are recommended if building the long fuselage version.
Even though it is drawn as one piece, and can be installed a such, I found that cutting the turtledeck into a forward, mid, and aft section which are installed separately makes for a much easier process.
The power pod is a minimal affair, and only necessary if using an FT firewall. If you're custom cutting your own firewall you can simply make it wide enough to glue to the forward end of the doubler plates.
If using the power pod, the open side of the C faces down. When you glue the firewall on, flush the bottom edge to the bottom of the power pod sides. Wrap tape around the firewall for reinforcement, then glue the power pod in, sliding the firewall up into the wide slot in the fuselage. (Pictures are of an earlier power pod. The one in the plans has significantly more down thrust now.)
The motor wires route up through the large opening above the motor and the ESC can glue or velcro in under the forward turtledeck. The reciever snugs nicely into the forward cockpit. I found that it is easier to install the turtledeck before the cabanes are installed, then trim the cutouts for the cabanes if necessary.
The cabane struts slot into the fuselage either side of the forward cockpit. To stiffen the cabanes, push a BBQ skewer down into the fuselage at the mark, following the angle of the cabane. Mark the top of the skewer about 1/8" longer than the cabanes, cut to length, then glue onto the cabane and into the fuselage. You'll want to mostly cut out the center portion of cabane struts, but leave it in place until after the wing is installed to help hold everything square.
The landing gear strut will also get a skewer glued along the leading edge for strength. Like the wing struts, cut the center out most of the way, but leave it in place until final assembly. The landing gear struts can't be fully installed until after the lower wing is in place.
The gear itself is 3/32" piano wire bent to shape (per the template in the plans) and glued into a foam sandwich. This assembly then slots into the doubler plates, much like the FT Scout or Edge. The half of the foam sandwich notched for the landing gear wire faces the nose of the plane. The wheels are approximately 2 1/8" diameter and don't need to be particularly light. Nose weight is your friend on this plane and heavy wheels will help push your CG forward.
That's enough for tonight. More to come!
Last edited:
Tench745
Master member
Like the fuselage, you can start with prepping the wings; cut, weed, bevel, etc.
The outboard wing struts will get the trailing edge trimmed off to allow for aileron movement.
Unlike the pictures, you'll want to cut the slots free from the lower wing's upper surface before gluing and don't glue the spar where the slot will be. The spar glues first to the upper surface, with the inner end flush to the root of the wing. For added durability, I recommend gluing a BBQ skewer either side of the spar.
Use the included dihedral gauge to set the lower wing dihedral and glue the wing roots together. There is no bottom skin in the lower wing's center section, so you may want to shim under the join while you're gluing to keep things supported.
Once the glue is set, flood hot glue into any gaps in the center seam from underneath, then you can glue the lower wing into the fuselage. The leading edge should flush up to the back edge of the landing gear.
Now you can glue in the belly plate. The forward portion will help tie together the two lower wing halves, so be sure to get enough glue on the spar, leading and trailing edges, and along both sides of the belly plate. The aft portion of the belly plate then folds down and glues in to add some rigidity to the aft portion of the cockpit area.
The upper wing is a little trickier. I found it easiest to glue the wing struts in place first, flushing to the leading edge of the wing, and then come back and run a bead of glue in the creases of the wing. Like the cabanes before, leave the center portions of the wing struts in place until after final assembly.
If you think of it, you can run your servo lead in the aft crease before gluing the wing strut in place. If you forget, like I always seem to, you'll need to cut a little notch in the top of the strut assembly to feed the servo lead through. Servos can be installed any time after the airfoil has been glued.
Once the struts are on you'll need to take a BBQ skewer and pierce through the upper portion of the wing strut and into the upper wing. Then set the upper wing in place in the slots on the lower wing and pierce through to the lower wing skin of the lower wing.
Take the upper wing/wing strut assembly back off and glue BBQ skewers (about 6 3/4" long) to the leading edge of the struts, pushing the skewer into the cavity you made for it in the upper wing.
Now you can glue the upper wing/wing strut assembly into the lower wing slots.
If you haven't done it yet, the upper wing center section gets glued to the cabanes, then the root of the upper wing panels glue to it.
There are little notches in the cabane to route your servo wires through to keep things neat. A couple dots of hot glue under the wires alon the wing keeps them from flopping in the breeze.
The outboard wing struts will get the trailing edge trimmed off to allow for aileron movement.
Unlike the pictures, you'll want to cut the slots free from the lower wing's upper surface before gluing and don't glue the spar where the slot will be. The spar glues first to the upper surface, with the inner end flush to the root of the wing. For added durability, I recommend gluing a BBQ skewer either side of the spar.
Use the included dihedral gauge to set the lower wing dihedral and glue the wing roots together. There is no bottom skin in the lower wing's center section, so you may want to shim under the join while you're gluing to keep things supported.
Once the glue is set, flood hot glue into any gaps in the center seam from underneath, then you can glue the lower wing into the fuselage. The leading edge should flush up to the back edge of the landing gear.
Now you can glue in the belly plate. The forward portion will help tie together the two lower wing halves, so be sure to get enough glue on the spar, leading and trailing edges, and along both sides of the belly plate. The aft portion of the belly plate then folds down and glues in to add some rigidity to the aft portion of the cockpit area.
The upper wing is a little trickier. I found it easiest to glue the wing struts in place first, flushing to the leading edge of the wing, and then come back and run a bead of glue in the creases of the wing. Like the cabanes before, leave the center portions of the wing struts in place until after final assembly.
If you think of it, you can run your servo lead in the aft crease before gluing the wing strut in place. If you forget, like I always seem to, you'll need to cut a little notch in the top of the strut assembly to feed the servo lead through. Servos can be installed any time after the airfoil has been glued.
Once the struts are on you'll need to take a BBQ skewer and pierce through the upper portion of the wing strut and into the upper wing. Then set the upper wing in place in the slots on the lower wing and pierce through to the lower wing skin of the lower wing.
Take the upper wing/wing strut assembly back off and glue BBQ skewers (about 6 3/4" long) to the leading edge of the struts, pushing the skewer into the cavity you made for it in the upper wing.
Now you can glue the upper wing/wing strut assembly into the lower wing slots.
If you haven't done it yet, the upper wing center section gets glued to the cabanes, then the root of the upper wing panels glue to it.
There are little notches in the cabane to route your servo wires through to keep things neat. A couple dots of hot glue under the wires alon the wing keeps them from flopping in the breeze.
Attachments
Tench745
Master member
Lastly, we get to add the finishing touches; the pretty stuff.
Cut a groove for the axle in the landing gear struts and slide them into place. A fillet of hot glue holds them to the fuselage and a generous coating of glue over the landing gear wire holds the rest.
The cowling and radiator are cut from cardstock.
The radiator is three pieces, one large piece that will serve as a backing plate and the two outlines that will glue to it and make up the edges of the radiator. If you want to get really fancy, you can use a piece of window screen for the backing plate.
The cowling sides are also three pieces. (These pictures are of an earlier version, so please ignore the shape discrepancy.)
It's surprisingly easy to make the louvers. Just place a straightedge about 1/8" from the cut line and work the pointed end of a skewer under the cardstock. Lightly lever the card upwards against the ruler, creating a gentle crease.
The small rectangular doors have a raised bead around the edges. If you place the cardstock on a piece of foamboard and press reasonably firmly wile tracing the guide line with a ballpoint pen or skewer it should raise the card sufficiently.
Once the cowling sides are glued onto the fuselage, a thin strip of card gets glued around the forward edge as the radiator surround.
Last but not least, the Hisso engine and exhaust can go on.
I printed mine with 30% infill, but these are a good place to hide some nose weight, so don't be afraid to print with 100% infill.
The cylinder heads sit 1/2" aft of the radiator and the top about 3/4" up from the edge of the turtledeck. It's marked on the plans, but I found measuring to be easier than trying to transfer the guide lines from the plans.
And there it is, you have a Hisso-powered Curtiss Jenny!
Cut a groove for the axle in the landing gear struts and slide them into place. A fillet of hot glue holds them to the fuselage and a generous coating of glue over the landing gear wire holds the rest.
The cowling and radiator are cut from cardstock.
The radiator is three pieces, one large piece that will serve as a backing plate and the two outlines that will glue to it and make up the edges of the radiator. If you want to get really fancy, you can use a piece of window screen for the backing plate.
The cowling sides are also three pieces. (These pictures are of an earlier version, so please ignore the shape discrepancy.)
It's surprisingly easy to make the louvers. Just place a straightedge about 1/8" from the cut line and work the pointed end of a skewer under the cardstock. Lightly lever the card upwards against the ruler, creating a gentle crease.
The small rectangular doors have a raised bead around the edges. If you place the cardstock on a piece of foamboard and press reasonably firmly wile tracing the guide line with a ballpoint pen or skewer it should raise the card sufficiently.
Once the cowling sides are glued onto the fuselage, a thin strip of card gets glued around the forward edge as the radiator surround.
Last but not least, the Hisso engine and exhaust can go on.
I printed mine with 30% infill, but these are a good place to hide some nose weight, so don't be afraid to print with 100% infill.
The cylinder heads sit 1/2" aft of the radiator and the top about 3/4" up from the edge of the turtledeck. It's marked on the plans, but I found measuring to be easier than trying to transfer the guide lines from the plans.
And there it is, you have a Hisso-powered Curtiss Jenny!
