GP Extra 300S .40
02-25-2002, 08:31 PM
#1
Senior Member
Thread Starter
Join Date: Jan 2002
Location: Bend,
OR
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
I recently ordered a Great Planes Extra 300S .40 kit through my LHS and am expecting it in the next day or two. I was wondering if there are any popular modifications or tips i should be aware of during the building process. If anyone has built one of these and has advice, i would love to hear it.
Also, i'm thinking about putting an OS 70FS or Saito 72 on it if i can come up with the money, and maybe doing flaperons as well. Any info regarding that is also appreciated. I may even go with a .91 sized motor simply because i really want a 4 stroke, and it's much easier to find used .91's than used .70/.72's. How does the plane fly with a .91? This is my 3rd plane and I would like to keep the wing loading absolutely as low as possible. Does the additional weight of the .91 make the plane more difficult to fly and land?
Thanks,
Troy
Also, i'm thinking about putting an OS 70FS or Saito 72 on it if i can come up with the money, and maybe doing flaperons as well. Any info regarding that is also appreciated. I may even go with a .91 sized motor simply because i really want a 4 stroke, and it's much easier to find used .91's than used .70/.72's. How does the plane fly with a .91? This is my 3rd plane and I would like to keep the wing loading absolutely as low as possible. Does the additional weight of the .91 make the plane more difficult to fly and land?
Thanks,
Troy
02-25-2002, 09:03 PM
#2
My Feedback: (1)
Join Date: Dec 2001
Location: South Plainfield, NJ
Posts: 1,149
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
Troy,
Extra's don't need flaps. I had the equivalent of the OS .70 in mine and it flew well. I changed engines to a Super Tiger .75 and it flies awsome. I think the Saito would be a great match as well. the only weak link is the plastic cowl.
Mark M.
Extra's don't need flaps. I had the equivalent of the OS .70 in mine and it flew well. I changed engines to a Super Tiger .75 and it flies awsome. I think the Saito would be a great match as well. the only weak link is the plastic cowl.
Mark M.
02-26-2002, 05:32 AM
#4
GP Extra 300S .40
Hello....This is one of my favorite planes so far. What can I tell you Mil, hmm(scratches head
) I've built 2 so far, virtually identical, in most respects. The kit is a really nice kit, and the instructs very thorough, follow them as close as you can, and you'll do great. You'll probably be better off then I was by going with a smaller engine, and with alot less work to do too.
I did the work x2, and after it's said and done, I can say the .91 was worth the work(I can say that now huh :stupid: ), although a good .70 or.72 would perform well also.
I powered both of mine with a .91 4-strokes, and I can tell you performance is absolutely awesome though. Another thing I can tell you is if you go with the big 4stroker, this is where you need to be aware! I figured this out after I lost the first one, and it has mostly to do with your tail group, and where my 2 planes differed the most. I experienced a flutter that literally folded the horizontal stab, and turned the plane into a yard dart. I figured this out after taking everything home and doing a post mortum in the shop. It all happened so fast, and there was no way to tell without piecing splinters back together (sort of)just to get the idea of what happened and it worked.
Anyways, build everything as stated, when coming to the stabs though, I used carbon-fiber on #2(DaveBrown brand), and put it across the span of the horizontal stab, leading edge, trailing edge, top and bottom. Also at that point, I added a small crutch on each half of the hor-stab for flying wire mounting. On these crutches I also used carbon-fiber to make hard points for the flying wires. I installed wires here top and bottom, and it does make a big difference. They(GreatPlanes) won't tell you this though, and it's OK, they can't recomend these mods. No prob, I'm not recomending them. Just telling you what I did.
Use the hinges they supply and cut them just like they tell you, I'm telling you these are tough when done right.
The fusalage is built exactly per plans, making sure your joints are tight the whole length down, and glue bonds as good as it should.
I would make a mod in the landing gear inner formers though, and go to 1/4" birch ply, instead of the 1/8" liteply. I read about this before I built the first one, and even though I knew, I didn't do it, and didn't do it on the second one either....until a rough landing took the gear off, along with the all the LG formers. I know for fact it was exact to manufacturers specs, and built well, and it still broke. I saw the week point of the design right there though.
Firewall is good, make sure to treat that and tank compartment liberally with dope or thinned epoxy.
Mounting the wing can be a trip, here follow plans and manual closely, and it will work fine.
I went to a 12 oz. tank, plans call for 10, but 12 is same outer dimension with extra length, no prob there. Don't use the rubber-band idea they tell you for securing tank. Use zip-ties around tank floor, just make sure they are cinched good. They are easy, cheap, and they won't go away on you like bands will. The 12 ozer gives me at least 14 to 15 minutes if not more, I just like the idea with a .91.
Go with fiberglass cowl and wheel pants if you can. The first few flights on #1 cracked the plastic cowl, a few more flights and off came the pants, something to do with power maybe
I notified GreatPlanes and they were really nice and sent me new parts, and I had already ordered glass from StansFibertech, but alas it was during this time that #1 met it's demise. I ordered #2 within a day or so. I just didn't get enough of the plane, It's going to take quite a while before I get enough of this one.
That's EXTRA building via DGrant, I do hope this helps, and you can PM me or send me an e-mail anytime.
Oh...did I mention I added 1/2" to the elevator, and 1 1/2" to the rudder, for that scale look
. Well I did it while building the tail, not really knowing how well your flying capabities are and how advanced you are, I can't recomend that, I'm just telling you I did it. 
Stick with recomended throws though, it's a good starting point.
Performance with these mods really is second to none in this size aerobatlc plane. It's unchallenged vertically, will tumble a** over teakettle as much as you want, inverted flat spins, upright flat spins, and lands at virtual crawl.
As usual though, keep weight in mind, even though your considering .91, weight is ever so critical in these aerobatic planes. Mine balanced perfectly with the battery in the rear of radio compartment, and reciever right under the cockpit.. and I run a 13/10 APC, 15% fuel. Weight is 6lbs, 4oz.(about 6oz more then #1, I attribute this to the general run of the kit wood, and flying wires)
After 2 of the planes, I can still say I would build another of these, and probably use the same scheme too(lots of it left). It's just one of those planes I want in my fleet, it's a winner.
No, it's not real fast although it definatey moves, but that engine pulls like a train, all the way out of sight.
So with that said I'm off to my shop to work on my 27% Extra. Hope this helps Mil.
) I've built 2 so far, virtually identical, in most respects. The kit is a really nice kit, and the instructs very thorough, follow them as close as you can, and you'll do great. You'll probably be better off then I was by going with a smaller engine, and with alot less work to do too.I did the work x2, and after it's said and done, I can say the .91 was worth the work(I can say that now huh :stupid: ), although a good .70 or.72 would perform well also.
I powered both of mine with a .91 4-strokes, and I can tell you performance is absolutely awesome though. Another thing I can tell you is if you go with the big 4stroker, this is where you need to be aware! I figured this out after I lost the first one, and it has mostly to do with your tail group, and where my 2 planes differed the most. I experienced a flutter that literally folded the horizontal stab, and turned the plane into a yard dart. I figured this out after taking everything home and doing a post mortum in the shop. It all happened so fast, and there was no way to tell without piecing splinters back together (sort of)just to get the idea of what happened and it worked.
Anyways, build everything as stated, when coming to the stabs though, I used carbon-fiber on #2(DaveBrown brand), and put it across the span of the horizontal stab, leading edge, trailing edge, top and bottom. Also at that point, I added a small crutch on each half of the hor-stab for flying wire mounting. On these crutches I also used carbon-fiber to make hard points for the flying wires. I installed wires here top and bottom, and it does make a big difference. They(GreatPlanes) won't tell you this though, and it's OK, they can't recomend these mods. No prob, I'm not recomending them. Just telling you what I did
.Use the hinges they supply and cut them just like they tell you, I'm telling you these are tough when done right.
The fusalage is built exactly per plans, making sure your joints are tight the whole length down, and glue bonds as good as it should.
I would make a mod in the landing gear inner formers though, and go to 1/4" birch ply, instead of the 1/8" liteply. I read about this before I built the first one, and even though I knew, I didn't do it, and didn't do it on the second one either....until a rough landing took the gear off, along with the all the LG formers. I know for fact it was exact to manufacturers specs, and built well, and it still broke. I saw the week point of the design right there though.
Firewall is good, make sure to treat that and tank compartment liberally with dope or thinned epoxy.
Mounting the wing can be a trip, here follow plans and manual closely, and it will work fine.
I went to a 12 oz. tank, plans call for 10, but 12 is same outer dimension with extra length, no prob there. Don't use the rubber-band idea they tell you for securing tank. Use zip-ties around tank floor, just make sure they are cinched good. They are easy, cheap, and they won't go away on you like bands will. The 12 ozer gives me at least 14 to 15 minutes if not more, I just like the idea with a .91.
Go with fiberglass cowl and wheel pants if you can. The first few flights on #1 cracked the plastic cowl, a few more flights and off came the pants, something to do with power maybe
I notified GreatPlanes and they were really nice and sent me new parts, and I had already ordered glass from StansFibertech, but alas it was during this time that #1 met it's demise. I ordered #2 within a day or so. I just didn't get enough of the plane, It's going to take quite a while before I get enough of this one.
That's EXTRA building via DGrant, I do hope this helps, and you can PM me or send me an e-mail anytime.
Oh...did I mention I added 1/2" to the elevator, and 1 1/2" to the rudder, for that scale look
. Well I did it while building the tail, not really knowing how well your flying capabities are and how advanced you are, I can't recomend that, I'm just telling you I did it. Stick with recomended throws though, it's a good starting point.Performance with these mods really is second to none in this size aerobatlc plane. It's unchallenged vertically, will tumble a** over teakettle as much as you want, inverted flat spins, upright flat spins, and lands at virtual crawl.
As usual though, keep weight in mind, even though your considering .91, weight is ever so critical in these aerobatic planes. Mine balanced perfectly with the battery in the rear of radio compartment, and reciever right under the cockpit.. and I run a 13/10 APC, 15% fuel. Weight is 6lbs, 4oz.(about 6oz more then #1, I attribute this to the general run of the kit wood, and flying wires)
After 2 of the planes, I can still say I would build another of these, and probably use the same scheme too(lots of it left). It's just one of those planes I want in my fleet, it's a winner.
No, it's not real fast although it definatey moves, but that engine pulls like a train, all the way out of sight.
So with that said I'm off to my shop to work on my 27% Extra. Hope this helps Mil.
02-26-2002, 02:23 PM
#6
GP Extra 300S .40
The landing gear area is a very weak design indeed...
If you don't feel like going through the hassle of replacing the lite-ply with aircraft grade then use 1/4-20 nylon bolts to attatch the landing gear, the bolts will break off long before the lite-ply will. I used this method on mine and it has worked very well.
For power I have an .80 4-stroke in mine right now, lots of fun, but too much power and too heavy. I originally had a Thunder Tiger .46 in it and that was a very nice combo, I am thinking of putting an Irvine .53 in mine now, that would be a perfect engine for this plane.
There would be two advantages in going with a .91 4-stroke, first, obviously, unlimited vertical. Second, the plane will behave much better in strong winds with the heavier engine up front.
If you don't feel like going through the hassle of replacing the lite-ply with aircraft grade then use 1/4-20 nylon bolts to attatch the landing gear, the bolts will break off long before the lite-ply will. I used this method on mine and it has worked very well.
For power I have an .80 4-stroke in mine right now, lots of fun, but too much power and too heavy. I originally had a Thunder Tiger .46 in it and that was a very nice combo, I am thinking of putting an Irvine .53 in mine now, that would be a perfect engine for this plane.
There would be two advantages in going with a .91 4-stroke, first, obviously, unlimited vertical. Second, the plane will behave much better in strong winds with the heavier engine up front.
02-26-2002, 08:16 PM
#8
Member
Join Date: Feb 2002
Location: Godovic, SLOVENIA
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
Sweet flying plane.
Hi guys!
My Extra is one of the sweetest planes I've ever had. Fell in love the first moment I saw one, and since I've built two.
The second one has some minor modifications, all of them are weight related. Result: ASP .80 FS powered ready to fly weighs 2200g!
Four Futabas 3001, five cell Rx Sanyo 1100AE pack, 10 oz. Dubro tank, home made CF landing gear, homemade fiberglass cowl and wheelpants. I laminated this in the original ABS supplied in the kit (some mould wax and PVA release agent does the trick). I also CNC milled scale instrument panel with glassed instruments installed from the back.
It's just awesome. It flies as is should (better than my old pattern ship Saphir), hovers at 60% throttle... and above all it's practical, fits in my VW Golf, doesn't burn a lot of expensive fuel and it takes a few moments to put it together. In the air it's very neutral, flies like a dream.
Pictures were taken before it's maiden flight, I'm gonna correct this ASAP.
Sašo
My Extra is one of the sweetest planes I've ever had. Fell in love the first moment I saw one, and since I've built two.
The second one has some minor modifications, all of them are weight related. Result: ASP .80 FS powered ready to fly weighs 2200g!
Four Futabas 3001, five cell Rx Sanyo 1100AE pack, 10 oz. Dubro tank, home made CF landing gear, homemade fiberglass cowl and wheelpants. I laminated this in the original ABS supplied in the kit (some mould wax and PVA release agent does the trick). I also CNC milled scale instrument panel with glassed instruments installed from the back.
It's just awesome. It flies as is should (better than my old pattern ship Saphir), hovers at 60% throttle... and above all it's practical, fits in my VW Golf, doesn't burn a lot of expensive fuel and it takes a few moments to put it together. In the air it's very neutral, flies like a dream.
Pictures were taken before it's maiden flight, I'm gonna correct this ASAP.
Sašo
02-26-2002, 08:22 PM
#9
GP Extra 300S .40
Mendes is correct here, and makes a good point about the wind. I flew the other day in some pretty stiff wind and with the bigger engine had no trouble. I'm sure partly due to power, but landing is even easier with a good breeze. The wing loading is higher with the bigger engine, without any wind it seems borderline snap tendency(although very slow), and with a breeze it's nice and pretty on landing. With alot of wind like the other day, it's absolutely no prob, just a click or 2 up on throttle, and the power just pulls it on in, and wind holds it up nicely.
Think light here though. I would be interested to know what it would be like at 5.5lbs or less. Showstopper I'm sure. That would be real tough if not impossible with a .91 4stroke. We'll see though.
Think light here though. I would be interested to know what it would be like at 5.5lbs or less. Showstopper I'm sure. That would be real tough if not impossible with a .91 4stroke. We'll see though.
02-26-2002, 08:24 PM
#10
Member
Join Date: Feb 2002
Location: Godovic, SLOVENIA
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
FS 91?
A friend of mine has two - one stock built with a ST.51. It weighs 2600g and flies excellent, the other is OS .91 FS powered, but it's too heavy (more than 3.3 kgs).
It leaps in the air with a lot of authority, feels rock-solid in the air but it's fast, which pays-off while landing. Now this is something that puts a new meaning to a word "hot".
Mine is extremely light, and this ASP .80 fits cowl very clean. The only thing that is sticking out is a valve cover. I made some other mods (CF gear visible on the pics), and it is worth of extra effort.
My throttle usually doesn't work on a downwinds, but I've tested it to fly as fast and as violent as it can, flutter is a non-issue.
Since it's very light, it stops on a dime - stall turns are elegant and very slooow, snaps fast and voilent, knife edge gracefull... Four point rolls are a breeze. Inverted flight requires almost no down-elevator (CG way back). You should try to put some extra effort in making your as light as I did. It's worth every extra minute.
Sašo
It leaps in the air with a lot of authority, feels rock-solid in the air but it's fast, which pays-off while landing. Now this is something that puts a new meaning to a word "hot".
Mine is extremely light, and this ASP .80 fits cowl very clean. The only thing that is sticking out is a valve cover. I made some other mods (CF gear visible on the pics), and it is worth of extra effort.
My throttle usually doesn't work on a downwinds, but I've tested it to fly as fast and as violent as it can, flutter is a non-issue.
Since it's very light, it stops on a dime - stall turns are elegant and very slooow, snaps fast and voilent, knife edge gracefull... Four point rolls are a breeze. Inverted flight requires almost no down-elevator (CG way back). You should try to put some extra effort in making your as light as I did. It's worth every extra minute.
Sašo
02-26-2002, 08:31 PM
#11
Senior Member
Thread Starter
Join Date: Jan 2002
Location: Bend,
OR
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
The engine i've got right now would probably be a very good match for the plane. I have an Enya .49 X. This motor seems pretty strong, with a 12.25x3.75 performance would probably be very good.
But i really want that 4 stroke sound and throttle response!! My Enya doesn't transition real well and has sort of a lag when throttling up. I've tried tuning it out but can't seem to.
Anyway, hopefully i can work up enough cash after the 1st of the month, and find a used .70 or .72 FS, I think that would be the ideal choice for me.
Also, thanks for the tip on nylon landing gear bolts, i will do that for sure. I think i will both beef up the plywood, and use nylon bolts, that way the airframe is sure to be undamaged by any minor mishaps.
But i really want that 4 stroke sound and throttle response!! My Enya doesn't transition real well and has sort of a lag when throttling up. I've tried tuning it out but can't seem to.
Anyway, hopefully i can work up enough cash after the 1st of the month, and find a used .70 or .72 FS, I think that would be the ideal choice for me.
Also, thanks for the tip on nylon landing gear bolts, i will do that for sure. I think i will both beef up the plywood, and use nylon bolts, that way the airframe is sure to be undamaged by any minor mishaps.
02-26-2002, 09:12 PM
#13
Member
Join Date: Feb 2002
Location: Godovic, SLOVENIA
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
CF
The .72 FS would be an ideal choice. Lots of power, lots of torque, unlimited performance. My first choice was my old TT .46 PRO which gives me unlimited vertical on a 2.7kg Easy Sport, but then I found this ASP .80 FS. It was used but almost new, idle for two years. It proved to be a great engine, combination with this Extra cannot be described otherwise as awesome. It's not overpowered at all. I use Bolly Clubman 13.5x6. Excellent.
CF landing gear? It's very simple. All you need is a blue-foam block. You draw the contour of the gear on the block, its thickness will give you a few landing gears after you cut the laminate (I had 80 mm thick block - that was sufficient for two set of gear). You cut the block in two pieces, following the contour. Then you need two strips of vacuum plastic (the one that canopies are made out of) as thin as possible, you treat both with PVA mould release on one side. You then laminate the CF and glass cloth (I used some, didn't have enough CF) with a high-quality epoxy, make a sandwich with the plastic strips (you turned it with PVA to the laminat, did you?) and then you put all this into your "mould" upside down - first you use the outer part, put your sandwich in and then you press in the iner part of the conutour. All this should be clamped langhwise and pressed from the top. In a day or two you have fabolous and light CF landing gear, which needs to be just trimmed, drilled and installed on your model.
Once you got the touch you know how much CF or glass to use to make the gear stiff or flexibile or strong enough for 4 or 6 lbs. And this simple method can be used for a lot of different types of landing gears - from parkflyers to giant scale machines. Contour is not the problem, as usually is when bending duraluminum or something else.
Slightly different method can be seen at http://www.geocities.com/CapeCanaveral/Cockpit/3328/
Great site - check it out!
Sašo
CF landing gear? It's very simple. All you need is a blue-foam block. You draw the contour of the gear on the block, its thickness will give you a few landing gears after you cut the laminate (I had 80 mm thick block - that was sufficient for two set of gear). You cut the block in two pieces, following the contour. Then you need two strips of vacuum plastic (the one that canopies are made out of) as thin as possible, you treat both with PVA mould release on one side. You then laminate the CF and glass cloth (I used some, didn't have enough CF) with a high-quality epoxy, make a sandwich with the plastic strips (you turned it with PVA to the laminat, did you?) and then you put all this into your "mould" upside down - first you use the outer part, put your sandwich in and then you press in the iner part of the conutour. All this should be clamped langhwise and pressed from the top. In a day or two you have fabolous and light CF landing gear, which needs to be just trimmed, drilled and installed on your model.
Once you got the touch you know how much CF or glass to use to make the gear stiff or flexibile or strong enough for 4 or 6 lbs. And this simple method can be used for a lot of different types of landing gears - from parkflyers to giant scale machines. Contour is not the problem, as usually is when bending duraluminum or something else.
Slightly different method can be seen at http://www.geocities.com/CapeCanaveral/Cockpit/3328/
Great site - check it out!
Sašo
02-26-2002, 10:52 PM
#15
Member
Join Date: Feb 2002
Location: Godovic, SLOVENIA
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
I am sorry that my english is far from perfect, but I am not a native speaker if this is of any comfort to you guys...
Of cour se such a gear weigh a lot less than comparable aluminum ones...
Mendes - I've checked your site - great Extra, I noticed that you have exactly the same engine on your Extra. The TT .46 PRO was my first choice, but my ASP weighs almost the same, so the difference in weight is not essential really. What's your experience with this engine?
BtW - your next project is 27% Extra with ST3000. Mine is 1/4 scale Su-31 (composite fuse, foam cored wings, it can already assembled, but...) with a ST3250 with tuned pipe. Of course it will have a CF landing gear
Sašo
Of cour se such a gear weigh a lot less than comparable aluminum ones...
Mendes - I've checked your site - great Extra, I noticed that you have exactly the same engine on your Extra. The TT .46 PRO was my first choice, but my ASP weighs almost the same, so the difference in weight is not essential really. What's your experience with this engine?
BtW - your next project is 27% Extra with ST3000. Mine is 1/4 scale Su-31 (composite fuse, foam cored wings, it can already assembled, but...) with a ST3250 with tuned pipe.
Of course it will have a CF landing gear Sašo
02-26-2002, 11:12 PM
#16
GP Extra 300S .40
frcac, The ASP .80 has been excellent, I am currently using a 14x6 Zinger on it, it gives me the best overall performance. I like it so much I have bought a .61 and 1.20 4-stroke from ASP also.
I was considering a Sukhoi as one of my next projects, great looking plane but I decided to go with a 42% biplane. I will be starting my Super Tigre for the break-in soon, I hope it runs well. Have you used your 3250 at all?
I was considering a Sukhoi as one of my next projects, great looking plane but I decided to go with a 42% biplane. I will be starting my Super Tigre for the break-in soon, I hope it runs well. Have you used your 3250 at all?
02-27-2002, 09:24 PM
#18
Member
Join Date: Feb 2002
Location: Godovic, SLOVENIA
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
DGrant: Good looking plane. Nice wire setup - how you do this? It must kill the idle vibes on the tail very efficient. I like the idea very very much.
Mendes: Bipes are also one of my preferences, but I decided to go with Su-31. 2m is just big enough (for now). ST 3250 is very user friendly, once properly broken-in and fine-tuned (spraybar can be rotated - you adjust midrange and throttle response with this simple trick) it's a beast. A friend of mine has 3000, regular muffler, Menz S 18x8 gives him 780 rpm. My 3250 with tuned pipe (didn't have the chance to test it) should give me 8000 rpm on a 20x10 (no nitro) according to a friend from New Zealand.
Sašo
Mendes: Bipes are also one of my preferences, but I decided to go with Su-31. 2m is just big enough (for now). ST 3250 is very user friendly, once properly broken-in and fine-tuned (spraybar can be rotated - you adjust midrange and throttle response with this simple trick) it's a beast. A friend of mine has 3000, regular muffler, Menz S 18x8 gives him 780 rpm. My 3250 with tuned pipe (didn't have the chance to test it) should give me 8000 rpm on a 20x10 (no nitro) according to a friend from New Zealand.
Sašo
02-28-2002, 12:50 AM
#19
GP Extra 300S .40
Thanks for the compliment, likewise, your Extra looks really nice too. Very clean.
The hardware for the wires is made by Sullivan, it's a kit that has all the necessary clevis's, attatchments, etc... It was about $20, and worth every penny. It also comes with Kevlar, you can use either one, Kevlar or brass cable, I just used the brass although the Kevlar is said to be much stronger. I don't think it's coming off anyways at this point.
Alot of the technique used to install I posted a few post's up from this(long post). In a nutshell, the wires were a planned install from the start of the plane. So the hardpoints were built in, and reinforced with carbon-fiber. Essentially I just added an additional truss on each half of the horizontal stab, I think it was only about 3/8" wide by 1/4"(thickness of stab), enough to give the mounting points good bite. The vert.stab I didn't need an extra truss other then to make the top truss about 1/4" wider, again for bite. I used DaveBrown carbon-fiber strip everywhere the mounts are located. I cut..oh about a half inch or so and glued it(CA) in the proximity of where I would actually bolt the wire. This "proximity" gave me room for adjustment to fine tune the placement. For the bottom mount I just added a very small slab of hard ply inside of fusalage.
Then came the wires themselves. There are quite a few ways you can go with the configurations. Get the flying wire kit and you'll know what I mean. It's very versatile.
I used the crimps, and solder links though. With clevis's at one end for adjustments.
It has needed some adjustments to keep it comfortably tight, and it seems to help the flight characteristics of the plane when adjusted. It just seems "right on" and solid.
I have first hand knowledge of how flexible these stabs are without this set-up. With carbonfiber(mentioned in previous post) and the wires, this is one tough plane.
I'm not saying that flex is a bad thing, matter of fact it can be a definate advantage, and this set-up does have some "give" to it.
I've totally put this plane to it's limits like this, big engine and all, still no prob.
I'm posting another pic, and hopefully this will be a little bit better of a shot. I'm working on getting a much better shot though. Talk to you laters.
The hardware for the wires is made by Sullivan, it's a kit that has all the necessary clevis's, attatchments, etc... It was about $20, and worth every penny. It also comes with Kevlar, you can use either one, Kevlar or brass cable, I just used the brass although the Kevlar is said to be much stronger. I don't think it's coming off anyways at this point.
Alot of the technique used to install I posted a few post's up from this(long post). In a nutshell, the wires were a planned install from the start of the plane. So the hardpoints were built in, and reinforced with carbon-fiber. Essentially I just added an additional truss on each half of the horizontal stab, I think it was only about 3/8" wide by 1/4"(thickness of stab), enough to give the mounting points good bite. The vert.stab I didn't need an extra truss other then to make the top truss about 1/4" wider, again for bite. I used DaveBrown carbon-fiber strip everywhere the mounts are located. I cut..oh about a half inch or so and glued it(CA) in the proximity of where I would actually bolt the wire. This "proximity" gave me room for adjustment to fine tune the placement. For the bottom mount I just added a very small slab of hard ply inside of fusalage.
Then came the wires themselves. There are quite a few ways you can go with the configurations. Get the flying wire kit and you'll know what I mean. It's very versatile.
I used the crimps, and solder links though. With clevis's at one end for adjustments.
It has needed some adjustments to keep it comfortably tight, and it seems to help the flight characteristics of the plane when adjusted. It just seems "right on" and solid.
I have first hand knowledge of how flexible these stabs are without this set-up. With carbonfiber(mentioned in previous post) and the wires, this is one tough plane.
I'm not saying that flex is a bad thing, matter of fact it can be a definate advantage, and this set-up does have some "give" to it.
I've totally put this plane to it's limits like this, big engine and all, still no prob.
I'm posting another pic, and hopefully this will be a little bit better of a shot. I'm working on getting a much better shot though. Talk to you laters.
03-03-2002, 09:29 AM
#21
Senior Member
Thread Starter
Join Date: Jan 2002
Location: Bend,
OR
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
Well, i got my kit, and have made payment on a Saito .72 (found on these very forums, thanks RCU!) and am expecting it next week.
I've got the tail surfaces and the wing built and am about half way through the fuse. I'm expecting it to take me a long time to cover the plane since this is my first kit and i'll probably go through a fair amount of trial and error on covering techniques.
I decided to build this plane exactly by the book and the only place i deviated so far is in adding some bracing under the wing sheeting in the first 2 rib bays because that is where i often pick up a plane and i dont want to break through the sheeting. I also added a little reinforcement to the lower front bulkhead, and the LG brackets.
What about the tailwheel bracket? I'm not sure i like the design here. It looks like it could put some stress on the hinges during impact and while just sitting. Also, there's no 'give' in the system, and it looks like it could cause damage to the servo if landing with the rudder deflected for a cross wind or something.
I think i may switch to a bracket i've seen that bolts to the bottom of the fuse to support the weight, and uses springs attached to control horns on the rudder for turning. That way the weight is off the hinges, and there are springs to absorb sudden shocks instead of little tiny plastic gears stripping in my servos.
Have any of you had any problems with the stock tailwheel?
Troy
I've got the tail surfaces and the wing built and am about half way through the fuse. I'm expecting it to take me a long time to cover the plane since this is my first kit and i'll probably go through a fair amount of trial and error on covering techniques.
I decided to build this plane exactly by the book and the only place i deviated so far is in adding some bracing under the wing sheeting in the first 2 rib bays because that is where i often pick up a plane and i dont want to break through the sheeting. I also added a little reinforcement to the lower front bulkhead, and the LG brackets.
What about the tailwheel bracket? I'm not sure i like the design here. It looks like it could put some stress on the hinges during impact and while just sitting. Also, there's no 'give' in the system, and it looks like it could cause damage to the servo if landing with the rudder deflected for a cross wind or something.
I think i may switch to a bracket i've seen that bolts to the bottom of the fuse to support the weight, and uses springs attached to control horns on the rudder for turning. That way the weight is off the hinges, and there are springs to absorb sudden shocks instead of little tiny plastic gears stripping in my servos.
Have any of you had any problems with the stock tailwheel?
Troy
03-03-2002, 12:13 PM
#22
Member
Join Date: Feb 2002
Location: Godovic, SLOVENIA
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
MiL, I didn't like the original tailwheel also. Although the rudder is attached to the fuse with extremely durable CA hinges, it just didn't felt right.
I made the tailwheel assembly myself. The 5mm ply releives the stress on the rudder and takes all the vibrations and punches on the airframe. The bottom back side of the fuse (in front of the rudder) is made out of liteply (otherwise I sheeted it with balsa except the landing gear stress plate). I thought about the spring wheel, and I found 2mm spring steel wire, which makes a perfect job each and every time.
Works great, and it's not complicated.
Sašo
I made the tailwheel assembly myself. The 5mm ply releives the stress on the rudder and takes all the vibrations and punches on the airframe. The bottom back side of the fuse (in front of the rudder) is made out of liteply (otherwise I sheeted it with balsa except the landing gear stress plate). I thought about the spring wheel, and I found 2mm spring steel wire, which makes a perfect job each and every time.
Works great, and it's not complicated.
Sašo
03-04-2002, 06:39 AM
#23
Senior Member
Thread Starter
Join Date: Jan 2002
Location: Bend,
OR
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
Thanks Sašo.
Another thing, is the single nylon bolt enough to secure the wing? Makes me a little nervous... i'm pretty sure it would hold up to most anything, but it's a SERIOUSLY important bolt... i think i might use 2. I've actually already set it up for the single, but i can go back and change it to 2.
Here's a pic of how mine will hopefully look when it's done. It's Patty Wagstaff's 1999 paint scheme. I definitely want a scale looking color scheme, since that's the whole reason i got this plane is for a scale look. I'm not sure how close i'll be able to come, given my lack of covering experience, but i'm gonna give it a shot anyway.
One last thing, what do i use to thin out my epoxy for fuel proofing the wood?
Another thing, is the single nylon bolt enough to secure the wing? Makes me a little nervous... i'm pretty sure it would hold up to most anything, but it's a SERIOUSLY important bolt... i think i might use 2. I've actually already set it up for the single, but i can go back and change it to 2.
Here's a pic of how mine will hopefully look when it's done. It's Patty Wagstaff's 1999 paint scheme. I definitely want a scale looking color scheme, since that's the whole reason i got this plane is for a scale look. I'm not sure how close i'll be able to come, given my lack of covering experience, but i'm gonna give it a shot anyway.
One last thing, what do i use to thin out my epoxy for fuel proofing the wood?
03-04-2002, 07:33 AM
#24
Member
Join Date: Feb 2002
Location: Godovic, SLOVENIA
Posts: 72
Likes: 0
Received 0 Likes
on
0 Posts
GP Extra 300S .40
Patty's 99 scheme is nice, but there are some problems with that checkerboard on the cowl. Quite some masking and painting as I see it. I like the old (white & blue) one better. But then again - there are varieties of schemes to choose from. You have to have the structure of the model (open bays) in front of you when you are choosing schemes.
Of course that single bolt is enough - can you immagine such a company as Great Planes to put unadequate hardware in their kits?
Trust me - it's enough. And if you still don't beleive me make an experiment. Try to rip one apart - when doing this consider the weight of your model and by your feeling you'll see, that that single nylon bolt is now tested to a minimum of 15g ...)
To thin epoxy use alcohol or methanol if you mix your own fuel. I don't like fuelproofing, but unfortunatelly is neccessary. But still - I covered my firewall in covering film. This can be seen on pictures of my Extra in previous posts. It's good looking and it's very practical.
Sašo
Of course that single bolt is enough - can you immagine such a company as Great Planes to put unadequate hardware in their kits?
Trust me - it's enough. And if you still don't beleive me make an experiment. Try to rip one apart - when doing this consider the weight of your model and by your feeling you'll see, that that single nylon bolt is now tested to a minimum of 15g ...
)To thin epoxy use alcohol or methanol if you mix your own fuel. I don't like fuelproofing, but unfortunatelly is neccessary. But still - I covered my firewall in covering film. This can be seen on pictures of my Extra in previous posts. It's good looking and it's very practical.
Sašo
03-04-2002, 07:33 AM
#25
GP Extra 300S .40
Mil, the single bolt is plenty. It will not go anywhere. You want a sheer point should your plane come out of the sky when your least expecting it. Mine did, and with little damage at all. I was about 2 mistakes high, and made 3 mistakes, well the ground came up to soon. The bolt broke, not the mount. What you can do here though is to install one of those threaded inserts though, those are so much safer then threading that wood.
I'm telling you they are tough planes, I thought mine bought the farm again during that episode, not the case though, it did sustain some damage although not serious. I was able to repair it without any trace, and took off 2 more ounces in the process.
My tail-wheel is stock, the way they do it standard GreatPlanes, as I have a Decathlon that has the same set up, it works fine for me though. No stress, the bushing that installs in the fusalage holds the weight. There is a bend in the wire that rests in that bushing, nothing gets to the rudder that shouldn't.
STAY LIGHT though, the way the kit is designed and the engine your using, STAY LIGHT and believe me, one bolt is enough. Just pay attention to the book when doing the wing seat/bolt area. It was in my first post to you. Your doing fine. Have fun
I'm telling you they are tough planes, I thought mine bought the farm again during that episode, not the case though, it did sustain some damage although not serious. I was able to repair it without any trace, and took off 2 more ounces in the process.
My tail-wheel is stock, the way they do it standard GreatPlanes, as I have a Decathlon that has the same set up, it works fine for me though. No stress, the bushing that installs in the fusalage holds the weight. There is a bend in the wire that rests in that bushing, nothing gets to the rudder that shouldn't.
STAY LIGHT though, the way the kit is designed and the engine your using, STAY LIGHT and believe me, one bolt is enough. Just pay attention to the book when doing the wing seat/bolt area. It was in my first post to you. Your doing fine. Have fun