Paramour
#26
Thread Starter
Join Date: Feb 2006
Location: Dorr, MI
Posts: 1,457
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
I've nailed down the fuse and fin contours. I've decided the best way to build it (since I want the fin to fair nicely into the fuse) is to build the fuse and fin as a single unit. All that's really left to do is work out the framework of the fuse and fin. I still can't help but wonder if really lightweight glass might not be a better way to go. As I look at this further, I begin to think 1/2A won't pull it well enough...but after all this work I'm going to leave the size as-is and power it however I need to. It definitely needs a canopy, I'm thinking a drastically trimmed-down bubble canopy would look good. I'm also turning ideas over in my mind for a sexery landing gear that won't detract from the look of the thing...it's too pretty to let it belly-flop.
*sigh* It won't fly a durn bit better than a Skydrill or SureShark though [&o]
*sigh* It won't fly a durn bit better than a Skydrill or SureShark though [&o]
#28
Senior Member
RE: Paramour
ORIGINAL: digital_trucker
*sigh* It won't fly a durn bit better than a Skydrill or SureShark though [&o]
*sigh* It won't fly a durn bit better than a Skydrill or SureShark though [&o]
#34
Senior Member
Join Date: May 2007
Location: napa, CA
Posts: 151
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
"I like the lines. It reminds me of some of the gas jobs of the 1930's."
Hey Dave,
Kind of like this one??
chuck
By the way Digital, Very nice design; got to love the beautiful wings!!
#35
Thread Starter
Join Date: Feb 2006
Location: Dorr, MI
Posts: 1,457
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
I still have to nail down the fuse construction, I had to set all airplane-related projects aside for little bit....I hope to have the design wrapped up soon so I can start on a prototype.
#36
Senior Member
RE: Paramour
For now DT, (as per the other thread) if you are going to mold fuses, you can make a plug out of ply wood, balsa and blue housing insulation foam. Ever build a Guillow's rubber powered scale job? Same idea, you are building in halves with formers at known stations and foam in between. You will need some kind of threaded holes in each half to mount them to the plexiglass later and wooden dowels to join them together during the final sanding and finish.
The base outline that all the stations are glued to will be thin plywood so you have a nice, sharp pair of corners to join together later at the mold seam, the station bulkheads can be balsa or thin ply with the blue foam sandwiched in between. The shaping process is a matter of sanding the blue foam to the profile that your bulkhead formers provide. Using a left/right half method this way is especially easy as you get a nice symmetrical fuselage this way. If you sand too far, you can cut out that station and re-profile it back. Use thick plywood for your fuse/spinner interface.
Once that is all done, fill the plug in with drywall filler and fill any dents in the foam or low spots you didn't think were worth fixing earlier-your parts will look wavy between where the bulkheads were. When this is done, you will use laminating resin (the same kind you will make the bodies out of) and paint the fuselage, covering it with some light glass (.75-1oz.) cloth.
When that has cured, you will have to "pot" your wing into the wing saddle. Mold release your wing. Using masking tape, mark out the shape of your wing fillets on the wing and carefully cut that pattern out of the masking tape. This is where you can really screw up, so make sure you get the wing on straight..... Ok, remove the portion of the tape inside your saddle and re-mold release it. Then use a paint marking pen to make an outline of the inside of the fillet outline. When it's dry re-mold release the center section you just painted and remove the rest of the masking tape from the monokote. At this point, you should have a wing with just an inside outline of the wing saddle marked in paint pen on it. Go ahead and lay up a layer of glass cloth and resin on the wing and let cure completely.
Mix up a batch of bondo and fill the wing saddle with it. Drop the wing in place on the fuse. Smoosh the excess glue out and wipe it away. Don't worry about putting the fillets in yet, just make sure you get a good interface between the fillet line and the fuse sides..... Bondo kicks off too quickly to work with in most cases. If you think you can swing it, you can form your fillet radiuses now with round tools dipped in Alcohol. Let it cure completely.
If you didn't get your fillets in, now will be the time. You can use either more bondo, or drywall filler but the filler will need a lot of time at room temperature to dry enough to sand. I prefer the drywall filler. Either way, sand your filler to shape using dowels with sand paper glued to them. You get good results this way. Ok, once this is done and you are happy with how the fillets look, glass them over.
Now your fuse is ready to start the finishing process, and it's also where you will need to really hunker down and care about your mold and the quality of the parts you will be making. Get some plastic modeller's filling paste and and start filling in the rough surface of the cloth you put on the fuse sides. Fill in any dents, and sand it down AFTER IT HAS COMPLETELY DRIED. This stuff shrinks a *LOT*, and you will go to bed all happy with yourself and come back the next day with low spots where you filled dents. At this point of the plug making process, the plug is most vulnerable to dings, dents and hangar rash it will seem like you hurt it every time you pick it up... press on. Once you are satisfied that the plug is filled and pretty, start painting. Get it good and wet, and make sure the paint won't be attacked by the alcohol in the PVA mold release-you'll destroy your plug getting it apart. When the first coat is dry, sand it down with light hand pressure and med. fine sandpaper. You will start to see high and low spots. Sand them out and start over. You might have to do this 5 or 10 times before it looks like a commercial fuse you would buy in a hobby shop. When the mold is *perfect*, or at least good enough to make you happy, put any recessed markings (like CG position marks/darts, embossed emblems etc.) in their appropriate spots, A vinyl cutting sign shop is a good place for this. Once done, put it away in an old sock in a place where you won't bump it.
We'll talk about the mold later....
The base outline that all the stations are glued to will be thin plywood so you have a nice, sharp pair of corners to join together later at the mold seam, the station bulkheads can be balsa or thin ply with the blue foam sandwiched in between. The shaping process is a matter of sanding the blue foam to the profile that your bulkhead formers provide. Using a left/right half method this way is especially easy as you get a nice symmetrical fuselage this way. If you sand too far, you can cut out that station and re-profile it back. Use thick plywood for your fuse/spinner interface.
Once that is all done, fill the plug in with drywall filler and fill any dents in the foam or low spots you didn't think were worth fixing earlier-your parts will look wavy between where the bulkheads were. When this is done, you will use laminating resin (the same kind you will make the bodies out of) and paint the fuselage, covering it with some light glass (.75-1oz.) cloth.
When that has cured, you will have to "pot" your wing into the wing saddle. Mold release your wing. Using masking tape, mark out the shape of your wing fillets on the wing and carefully cut that pattern out of the masking tape. This is where you can really screw up, so make sure you get the wing on straight..... Ok, remove the portion of the tape inside your saddle and re-mold release it. Then use a paint marking pen to make an outline of the inside of the fillet outline. When it's dry re-mold release the center section you just painted and remove the rest of the masking tape from the monokote. At this point, you should have a wing with just an inside outline of the wing saddle marked in paint pen on it. Go ahead and lay up a layer of glass cloth and resin on the wing and let cure completely.
Mix up a batch of bondo and fill the wing saddle with it. Drop the wing in place on the fuse. Smoosh the excess glue out and wipe it away. Don't worry about putting the fillets in yet, just make sure you get a good interface between the fillet line and the fuse sides..... Bondo kicks off too quickly to work with in most cases. If you think you can swing it, you can form your fillet radiuses now with round tools dipped in Alcohol. Let it cure completely.
If you didn't get your fillets in, now will be the time. You can use either more bondo, or drywall filler but the filler will need a lot of time at room temperature to dry enough to sand. I prefer the drywall filler. Either way, sand your filler to shape using dowels with sand paper glued to them. You get good results this way. Ok, once this is done and you are happy with how the fillets look, glass them over.
Now your fuse is ready to start the finishing process, and it's also where you will need to really hunker down and care about your mold and the quality of the parts you will be making. Get some plastic modeller's filling paste and and start filling in the rough surface of the cloth you put on the fuse sides. Fill in any dents, and sand it down AFTER IT HAS COMPLETELY DRIED. This stuff shrinks a *LOT*, and you will go to bed all happy with yourself and come back the next day with low spots where you filled dents. At this point of the plug making process, the plug is most vulnerable to dings, dents and hangar rash it will seem like you hurt it every time you pick it up... press on. Once you are satisfied that the plug is filled and pretty, start painting. Get it good and wet, and make sure the paint won't be attacked by the alcohol in the PVA mold release-you'll destroy your plug getting it apart. When the first coat is dry, sand it down with light hand pressure and med. fine sandpaper. You will start to see high and low spots. Sand them out and start over. You might have to do this 5 or 10 times before it looks like a commercial fuse you would buy in a hobby shop. When the mold is *perfect*, or at least good enough to make you happy, put any recessed markings (like CG position marks/darts, embossed emblems etc.) in their appropriate spots, A vinyl cutting sign shop is a good place for this. Once done, put it away in an old sock in a place where you won't bump it.
We'll talk about the mold later....
#37
Senior Member
RE: Paramour
ORIGINAL: digital_trucker
*sigh* It won't fly a durn bit better than a Skydrill or SureShark though [&o]
*sigh* It won't fly a durn bit better than a Skydrill or SureShark though [&o]
Yeah, it will. If you design it to be as slow as a Sureshark or Skydrill, it will be. Your airplane has a thin wing, perfect for a hot but friendly airfoil like the RG14 or MH30. The fuse has a nice, gradual taper to it-this thing has the potential to haul ba!!$... I know a thing or two about fast airplanes, and there's not a lot about your design that holds it back from going fast. The long tail moment is going to make it very friendly too.
It's going to need a special motor too, like an MP JET .061BB Diesel.
#38
Thread Starter
Join Date: Feb 2006
Location: Dorr, MI
Posts: 1,457
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
It has a TRUE Clark-Y airfoil, the only concession being the trailing edge that will scale-wise be a little thick (limitations of scale, y'know). You'll all probably be a little sickened to hear it, but I'm designing it around a Common Sense R/C lekky system. It would do fine with any 1/2A engine, even so. I've also changed the wing engineering to to duplicate the wing construction of an Early R/C Schoolgirl I've been building...that method of construction is amazingly light and rigid. I *think* I can make it work with this Clark-Y airfoil and elliptical wing (we'll see).
#39
Senior Member
RE: Paramour
ORIGINAL: digital_trucker
It has a TRUE Clark-Y airfoil, the only concession being the trailing edge that will scale-wise be a little thick (limitations of scale, y'know). You'll all probably be a little sickened to hear it, but I'm designing it around a Common Sense R/C lekky system. It would do fine with any 1/2A engine, even so. I've also changed the wing engineering to to duplicate the wing construction of an Early R/C Schoolgirl I've been building...that method of construction is amazingly light and rigid. I *think* I can make it work with this Clark-Y airfoil and elliptical wing (we'll see).
It has a TRUE Clark-Y airfoil, the only concession being the trailing edge that will scale-wise be a little thick (limitations of scale, y'know). You'll all probably be a little sickened to hear it, but I'm designing it around a Common Sense R/C lekky system. It would do fine with any 1/2A engine, even so. I've also changed the wing engineering to to duplicate the wing construction of an Early R/C Schoolgirl I've been building...that method of construction is amazingly light and rigid. I *think* I can make it work with this Clark-Y airfoil and elliptical wing (we'll see).
I'm only sickened to hear you are using Common Sense instead of something made my Astroflight, Nuemotors etc. As for the wing, it WILL work with a Clark-Y. It's a question of what you want out of it though, and a Clark-Y is an airfoil meant to be used on full sized airplanes. The model specific airfoils meant to work at our Reynolds numbers are a real improvement over a Clark-Y. Of Course, fast is a relative term and what is considered "fast" to one guy may not be to another and you may be happy with the wing's flying characteristics and speed. For my money, I'd go with a sweetheart like the RG-14 in the stock thickness. Just seems kinda counterintuitive to build a sleek composite airframe like the Paramour and then hobble it's capability with a draggy, if friendly airfoil.
But, if that's what you want in your project and nobody else agrees to heck with 'em! They can do it better for themselves![8D]
#41
Thread Starter
Join Date: Feb 2006
Location: Dorr, MI
Posts: 1,457
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
The RG-14 does look rather interesting. It would be much harder to build though, do you suppose the wing could be made in the same fashion as the fuse?
#42
Senior Member
RE: Paramour
Sure, the wing could be hollow molded-but as much work as a fuse mold is, a wing mold would be harder for you as you would be working from a ribbed structure to try and get a true airfoil along the wing. That, and the making of the mold is harder due to how you have to make the parting boards, get a parting line along the LE and TE etc.
What is the issue with building a built up wing in an airfoil other than the Clark-Y? Is it because the ribs are not flat on the bottom and making it harder to position the ribs without warping the wing?
What is the issue with building a built up wing in an airfoil other than the Clark-Y? Is it because the ribs are not flat on the bottom and making it harder to position the ribs without warping the wing?
#44
Senior Member
RE: Paramour
Foam core would be the way I would go, but you can't easily do a foam core elliptical wing. Then again, wire cut wings are dead easy and built up elliptical wings are not.
It is possible and I've seen an article on how to do it though. FM maybe?
Might be worth looking into DT.
It is possible and I've seen an article on how to do it though. FM maybe?
Might be worth looking into DT.
#46
Senior Member
My Feedback: (1)
Join Date: Sep 2003
Location: Mission,
TX
Posts: 521
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
What,no foam,no CAD,no calculator? Pencil math,french curve,
single edge razor blade was about it.Also no Dremel tools, no
mail order wood and no rock and roll. Craftsmanship is still
with us though as evidenced by the work done by all these
1/2 Aers. Sure is more convenient now.
Ralph
single edge razor blade was about it.Also no Dremel tools, no
mail order wood and no rock and roll. Craftsmanship is still
with us though as evidenced by the work done by all these
1/2 Aers. Sure is more convenient now.
Ralph
#47
Senior Member
Join Date: Feb 2003
Location: Slidell,
LA
Posts: 501
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
ORIGINAL: combatpigg
I would use poly-urethane foam to shape the wing, then chop it up into rib stations to make templates. Here is Carl Goldberg launching a free flight model that is made out of 10,000 little sticks of wood.
I would use poly-urethane foam to shape the wing, then chop it up into rib stations to make templates. Here is Carl Goldberg launching a free flight model that is made out of 10,000 little sticks of wood.
I relate to your Carl Goldberg photo but probably not in the way you intended! <grin>.
My first ever model was a 10 cent Hi-Flier kit (plus a penny for a small tube of cement) that I built back around 1941. As an eight year old kid I thought it had 10,000 pieces but I finished it (it actually flew) and I bet that I was as proud of it as Carl was of his Sailplane. For me it’s that same stick and tissue construction that brings back those memories.
Al
#50
Senior Member
Join Date: Feb 2003
Location: Slidell,
LA
Posts: 501
Likes: 0
Received 0 Likes
on
0 Posts
RE: Paramour
ORIGINAL: combatpigg
Al, did Goldberg kit that elliptical plane? If so, there must have been a special Brotherhood of guys who successfully built and flown one?
Al, did Goldberg kit that elliptical plane? If so, there must have been a special Brotherhood of guys who successfully built and flown one?
But you have thrown the gauntlet. I am tempted to try to replicate the Comet Sailplane scaled down stick for stick to .010 size. Wow, I can see it now! Need the plans first tho.
Al