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-   -   GP extra 300s build (https://www.rcuniverse.com/forum/kit-building-121/11460885-gp-extra-300s-build.html)

t-max97 03-28-2013 09:30 PM

GP extra 300s build
 
I just ordered a Great Planes extra 300s .40 kit, this will be my first kit build so any tips would be great, Im in no hurry to build it since I wouldn't feel comfortable flying it now anyway, I have about 8-10 flights on my big stik .40 since I stepped up to it from a trainer so not quite there yet but Ill have it ready for when I am. It should be here early next week, I'll take pictures and post them as I build it if anyone is interested. I haven't decided on the engine yet, does anyone have experience with magnum 4 strokes?

mattnew 03-29-2013 05:51 AM

RE: GP extra 300s build
 
I would be interested in seeing how this thing goes together.... I just did a thread on a great planes rv-4 build that I would imagine builds similarly<div>
</div><div>I've heard nothing but good things about the magnum 4 strokes, basically a copy of the late 90's O.S. engines. I have no experience with them though unfortunately. </div><div>
</div><div>Tips:</div><div>
</div><div>1. when in doubt go by the plans vs the instruction booklet. if you duplicate the plans the plane will go together.... instruction booklets while helpful can have mistakes.</div><div>2. go slow, and be sure of what you want to do before you glue....kind of like measure twice cut once.</div><div>3. have fun, if you start rushing force yourself to take a break, its those impatient times that mistakes happen.</div><div>4. For gluing wood, nothing is stronger than wood glue, nothing is faster than CA, both glues are stronger than balsa wood, meaning the wood will break before your joint. For gluing metal/plastic to wood, think epoxy, sometimes CA, consult the instruction book.</div><div>
</div><div>i've always felt that building is a huge part of the hobby. Enjoy it</div><div>
</div><div>
</div>

karolh 03-29-2013 07:01 AM

RE: GP extra 300s build
 
Ditto to all of the above, and if all else fails then ask as many questions as needed.

t-max97 03-29-2013 07:56 AM

RE: GP extra 300s build
 


ORIGINAL: mattnew

I would be interested in seeing how this thing goes together.... I just did a thread on a great planes rv-4 build that I would imagine builds similarly<div>
</div><div>I've heard nothing but good things about the magnum 4 strokes, basically a copy of the late 90's O.S. engines. I have no experience with them though unfortunately. </div><div>
</div><div>Tips:</div><div>
</div><div>1. when in doubt go by the plans vs the instruction booklet. if you duplicate the plans the plane will go together.... instruction booklets while helpful can have mistakes.</div><div>2. go slow, and be sure of what you want to do before you glue....kind of like measure twice cut once.</div><div>3. have fun, if you start rushing force yourself to take a break, its those impatient times that mistakes happen.</div><div>4. For gluing wood, nothing is stronger than wood glue, nothing is faster than CA, both glues are stronger than balsa wood, meaning the wood will break before your joint. For gluing metal/plastic to wood, think epoxy, sometimes CA, consult the instruction book.</div><div>
</div><div>i've always felt that building is a huge part of the hobby. Enjoy it</div><div>
</div><div>
</div>
I got some Sig aliphatic resin wood glue and I already have 30min epoxy and CA. I'll research Magnum engines a little more. Thanks for the tips.

mattnew 03-29-2013 09:54 AM

RE: GP extra 300s build
 
lots of good engines out there.<div>
</div><div>couple thoughts... and these are purely my own, plenty of people can and will disagree.</div><div>
</div><div>- Aerobatic .40 sized plane... keep it light. 4 strokes tend to weigh more than 2 strokes, and with less power for the same displacement. I love my 4-strokes, I have them in aerobatic planes... but you do sacrifice some with a higher wing loading ( weight )... a magnum xl52 is $149 from tower... O.S. 46AXII 2-stroke is the same price... both would be great fits for the plane. i'd probably go with the O.S. and save the 2 ounces. If it were a scale plane or warbird I might say go with the 4 stroke since it will obviously have a more pleasing sound.</div><div>
</div><div>- Evolution is making the 10gx which is a gasoline engine designed to replace a .46 sized 2 stroke. If your at all like me with your hobby shops all an hour or so away and getting glow fuel is a pain... may be something worth thinking about.... I have nothing to gain here.. its just a thought since your researching engines. I have 1 of these... have yet to fire it up yet so i can't comment on its quality.</div><div>
</div><div>Good luck...</div><div>
</div>

t-max97 03-29-2013 11:57 AM

RE: GP extra 300s build
 

ORIGINAL: mattnew

lots of good engines out there.<div>
</div><div>couple thoughts... and these are purely my own, plenty of people can and will disagree.</div><div>
</div><div>- Aerobatic .40 sized plane... keep it light. 4 strokes tend to weigh more than 2 strokes, and with less power for the same displacement. I love my 4-strokes, I have them in aerobatic planes... but you do sacrifice some with a higher wing loading ( weight )... a magnum xl52 is $149 from tower... O.S. 46AXII 2-stroke is the same price... both would be great fits for the plane. i'd probably go with the O.S. and save the 2 ounces. If it were a scale plane or warbird I might say go with the 4 stroke since it will obviously have a more pleasing sound.</div><div>
</div><div>- Evolution is making the 10gx which is a gasoline engine designed to replace a .46 sized 2 stroke. If your at all like me with your hobby shops all an hour or so away and getting glow fuel is a pain... may be something worth thinking about.... I have nothing to gain here.. its just a thought since your researching engines. I have 1 of these... have yet to fire it up yet so i can't comment on its quality.</div><div>
</div><div>Good luck...</div><div>
</div>
Yes the closest hobby shop "hobby town usa which kinda sucks" Is about 45 minutes away and glow fuel isn't exactly cheap, I completely forgot out the new evolution gasser, I will very much consider that because I really hate having to buy glow fuel but I don't want electric lol. It's been shipped!

tobydogs 03-29-2013 04:45 PM

RE: GP extra 300s build
 
1 Attachment(s)
i built the 300s years before i'd be ready to fly it. in fact it maideened last fall and the batteries were to old so the lvc on the castle 100 amp ice esc cut throttle. it was an easy repair.

your going to love the build and the wing builds flat on the build table unlike the gp rv4-4o, i really enjoyed the build and the few flights were fun and now my battery ell count will be 7,not 6cells. also went up to 40c packs 4000mah. she should fly great.


t-max97 03-29-2013 06:04 PM

RE: GP extra 300s build
 
Looks great, you don't happen to have anymore picture's do you? If not it's fine don't worry about it.

tobydogs 03-29-2013 07:24 PM

RE: GP extra 300s build
 
1 Attachment(s)
i have a bunch of hanger pictures with the turnigy 50 55 580kv motor mounted in it while it hung on the ceiling for years...lol....but i now have an eflite power 60,also got rid of the 100amp turnigy and now have a castle 100 amp ice.[china cheap kills kits!!}
the batteries i used in the hog bipe were only 20c 4000mah and old when i maidenedthe extralast fall,i beleive the wot drew to much power out of the 20c batteries and the esc did the dreaded lvc slow down on the motor,she harriered down tearing off there wing &amp;mount block and lg. i just increased the battery boxsize to hold the new batteries...3cell 40c 4000mah,and 4cell 40c 4000mah run in series to get 7cells. i am very excited to fly her now .

i'll get some airshots soon once my rusty flying skills improve from a long winter of building.this winter iadded a bird of time ,and am building the gp rv 4-40 again. i had this one on cheap china stuff and lost connection to the rx through the cheap 85amp turnigy esc. new rv will be powered just like the exta is now.




t-max97 03-30-2013 04:29 AM

RE: GP extra 300s build
 
Thanks! great looking plane, I like the others too. Did you add the rudder counter balance or is that the design? Iv'e been tempted to get some hobbyking electronics but there are so many mixed reviews it's almost worth paying more for name brand stuff just to have peace of mind lol. What servo's are you using? I wasn't sure if standard futaba s3003's would be enough or not.

tobydogs 03-30-2013 09:53 AM

RE: GP extra 300s build
 
counter balance is the stock design,but others have increased the control surfaces for improved performance on the rudder and elevator. i really fly the hog bipe scale and the extra will be pushed harder for aerobatics but nothing to difficult since my skills have a long way to go.
my # 1 suggestion and i hope you take it since the build is a wonderful project...don't go cheap on the componets to fly this bird. standard servos are fine if your not pushing knif edge loops...lol....but otherwise up the quality of the servos if your pulling hard g forces. i'm using hitec 485's standards.

if your going electric,the eflite power 60 with 7cell 40c 4000mah battery and a castle creations 100amp ice will be plenty of jucie to get 7 min flight with throrrle to spare for those go arounds to land. i get 10min flights on similar setup with the hogbipe. i also use 6v aux battery for the rx and servos.

i just got home from flying and hope you get some air time,it was breezy and beautiful!!

t-max97 03-30-2013 06:37 PM

RE: GP extra 300s build
 
Thanks ill check out some stronger servo's, I will be going glow or gas powered "evolution 10gx", not sure which one yet. I got to fly my big stik a good bit today too, great weather with a sunburn to prove it :D.

pt19 flyer 04-01-2013 06:46 PM

RE: GP extra 300s build
 
hi gang
hope you guys have better luck with the x300 than I did. was excellent flyer with one exception, get a
dead stick and you have a crash on your hands. very poor in idle glide mode. you must land the dude
with some power, never a glide in landing, just tip stalls and down she comes.

pe19 flyer

mattnew 04-02-2013 06:56 AM

RE: GP extra 300s build
 
dead stick rules. Keep your:
1. Nose down
2. speed up.
If you can't reach the runway following 1 &amp; 2. find the next best place and land there.



It won't be a glider but if you follow 1 &amp; 2 you should be fine.


t-max97 04-02-2013 11:38 AM

RE: GP extra 300s build
 
Thanks guys, it came this morning and I already started on it, ill post pictures soon.

tobydogs 04-02-2013 02:08 PM

RE: GP extra 300s build
 
very cool max,i am looking forward to following alongyour build. it's been a long time since i built the 300 and pictures will bring back good memories of the build. it's funny how some kits are fun and others like the GPRV 4-40 test ones temper...lol....at least this time the 4-40 is turning out great,so maybe it'll become a better memory than the previous RV builds i did.

i really liked the way the 300's wing builds out and its pretty big at 60+inch's ws. take plenty of pictures.!!!

mattnew 04-02-2013 04:18 PM

RE: GP extra 300s build
 
pics are a must! I'll be watching this closely as it may be my next build.. I just got a midwest cap 232 in that I'm going to build b/c I couldn't find the midwest extra anywhere... I contemplated the GP 300 quite a bit.. the price is certainly nice... would like to know how it goes together.<div>
</div><div>We'll be waiting!</div>

biam 04-03-2013 03:36 PM

RE: GP extra 300s build
 
Hi t-max, like I said in the other post, I didnt like the engine on mine. Had an old f.p .60 in her, and it really liked fuel, that being said you had to remember to look at your watch, which I failed to do at times. The result was a lot of dead stick landings, which are not fun as indicated by other posters! All in all if I had her back at least a .70 four stroke would be in it, kinda partial to four strokes anyway. I think a .52 would not be enough for this model. As far as magnum engines go I like them. Have six of the four strokes in the fleet now. A .70,.80.91 and three .52's. Good luck with your build, and happy landings!;)

t-max97 04-03-2013 03:58 PM

RE: GP extra 300s build
 
1 Attachment(s)
Thanks guys, it going together fairly easy so far just alot of tedious work, I'm enjoying it though. Here are some pictures.

mattnew 04-04-2013 04:56 AM

RE: GP extra 300s build
 
Very nice, looks like your making some good progress!


What is your building board made out of? I noticed that some of your builds appear to be going across seams in whatever it is, just be careful with that and make sure they two pieces are good and level and flat! If at all possible you might want to try to avoid building across the seams when you have to pin things down.

t-max97 04-04-2013 07:39 AM

RE: GP extra 300s build
 
Thanks.....It's on a table that I didn't want ruined lol so I put some scrap pieces of some kind of composite like 1/8 board that has a slick finish on it, it all lays flat and I put tape over the seems, I think it's fine.

tailskid 04-04-2013 10:13 AM

RE: GP extra 300s build
 
I just came across this thread: http://www.rcgroups.com/forums/showthread.php?t=1865542 of the same plane.

t-max97 04-04-2013 11:42 AM

RE: GP extra 300s build
 


ORIGINAL: tailskid

I just came across this thread: http://www.rcgroups.com/forums/showthread.php?t=1865542 of the same plane.
Awesome, thanks!

DGrant 04-04-2013 01:56 PM

RE: GP extra 300s build
 
I have one of these I built 13yrs ago. Its still in great shape.. I have a Magnum .91 4-stroke in it.. It flies awesome... these are great models. I would recomend getting rid of the ABS plastic stuff.. and get a nice cowl and wheel pants from someone like Fiberglass Specialties... The plastic stuff won't last.. maybe if you went electric it might for a bit.. but if you put glow or gas..just go fiberglass.

Also..shore up the landing-gear plate a bit. Mine broke.. and it really shouldn't have... After looking the design, theres just a few areas that should be "doubled up"..which would make that whole undercarriage much stronger.. which is essentially what I did upon repair. I crashed it one other time and basically "cracked its back".. but it was really an unbelievably easy fix.. and the repair is undetectable on the outside.. and virtually undetectable inside.. I learned every one of these aerobatic planes with one-peice wing has a weak point just below the canopy.. thats the narrowest major structure area on the plane

I also added flying wires on the rear-stab group... that really strengthened the tail areas.. I actually built 2 of these.. both with the .91.. the first one went in..due to "flutter" on the tail surfaces... that I think was induced by the larger .91 engine(my bad).. the second one(that I'm speaking about) got flying wires on the tail.. and another .91 4-stroke.. and its lasted the test of time. I'm sure I've got a few-hundred flights easy... With the .91 its always unchallenged vertically.. Its no 3D plane by any stretch.. but to fly nice big patterns and graceful aerobatics theres none better in my book.

My Extra is pictured in my avatar.. its been one of my favorites from day one.. so much so I built 2.. then I built a 27% version(Midwest Extra300)..but thats another story...

So... lets see an Extra come out of that box of wood and stuff.. Great project there.. have fun. Hope to see it soon. :)

t-max97 04-05-2013 04:07 PM

RE: GP extra 300s build
 

ORIGINAL: DGrant

I have one of these I built 13yrs ago. Its still in great shape.. I have a Magnum .91 4-stroke in it.. It flies awesome... these are great models. I would recomend getting rid of the ABS plastic stuff.. and get a nice cowl and wheel pants from someone like Fiberglass Specialties... The plastic stuff won't last.. maybe if you went electric it might for a bit.. but if you put glow or gas..just go fiberglass.

Also..shore up the landing-gear plate a bit. Mine broke.. and it really shouldn't have... After looking the design, theres just a few areas that should be ''doubled up''..which would make that whole undercarriage much stronger.. which is essentially what I did upon repair. I crashed it one other time and basically ''cracked its back''.. but it was really an unbelievably easy fix.. and the repair is undetectable on the outside.. and virtually undetectable inside.. I learned every one of these aerobatic planes with one-peice wing has a weak point just below the canopy.. thats the narrowest major structure area on the plane

I also added flying wires on the rear-stab group... that really strengthened the tail areas.. I actually built 2 of these.. both with the .91.. the first one went in..due to ''flutter'' on the tail surfaces... that I think was induced by the larger .91 engine(my bad).. the second one(that I'm speaking about) got flying wires on the tail.. and another .91 4-stroke.. and its lasted the test of time. I'm sure I've got a few-hundred flights easy... With the .91 its always unchallenged vertically.. Its no 3D plane by any stretch.. but to fly nice big patterns and graceful aerobatics theres none better in my book.

My Extra is pictured in my avatar.. its been one of my favorites from day one.. so much so I built 2.. then I built a 27% version(Midwest Extra300)..but thats another story...

So... lets see an Extra come out of that box of wood and stuff.. Great project there.. have fun. Hope to see it soon. :)
Good to hear and thanks for the info, how are stalls and landings?

Here's a few more pictures, ill upload more in a minute. Btw how do you cut yourself without even knowing it lol? Trying to upload them but I keep getting 500 internal error, ill try again later.




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