hgiles

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I will be starting a build of the China Models 71" Spitfire distrubuted by GSP (GiantScalePlanes). I will post the details of the build to this thread for others interested and for my own reference as time goes on. If anyone else has any helpful hints or guidance, please feel free to chime in.

My Spit will be powered by a Thunder Tiger .91 FS. I am not a speed freak nor a 3D freak, so I am thinking this will be adequate. Review on RCU suggests any .91 FS should do fine. TT .91s are supposed to be better than most where power is concerned. It is relatively inexpensive too. Also this engine is something of a boat anchor, so I think it will make balancing easier. I think it is better to put as much weight as is reasonable in the nose with a heavy engine and add weight to the tail, if necessary (ballast further from the CG has a greater mechanical (leverage) advantage, so you need less of it). I think this is the better than adding a ton to the nose and over paying for a super light power plant.

I have a set of 103HD Spring Air retracts going in mine. Century Jet makes a custom set, but I can't remember the number (31899?). Any 85 or 90 deg retracts with wire should work. Struts can be added later after getting the wire bent to the required shape mandated by the wing geometry. Mechanical retracts just will not do.

Hardware is reportedly marginal, consider upgrading. I like the black Dubro 4 screw T style control horns and steel clevises. I am considering 2-56 steel hardware to keep the tail light. Maybe pull-pull for the rudder and/or elevator if it can be done.

Standard Futaba servos 3003 on throttle, 3004 everywhere else. Review on RCU suggests standard servos will be fine. Most everything is still on its way to my door, so I haven't actually seen much of this stuff yet, hence the process is subject to change.

Any advice is appeciated, especially if it keeps me from making a major mistake!

BlueMax3

My Feedback: (1)

Hello,

I have this ARF with a Saito 100 and the weight of the TT91 engine will not be a problem at all and will reduce the amount of weight you have to add to the nose. I can't imagine that it will end up nose heavy with at engine. I used 4-40 pushrods all around and if I were to do it again, I would strongly consider 2-56 h/w, at least aft of the elevator Y to save weight in the tail. I think standard servos are fine. Please let us know how the retract installation goes.

Travis

SJN

Ohh goodie [sm=thumbup.gif]

Im expecting mine in the mail next week. Can you take some pictures of yours now and during the build ?

hgiles

My Feedback: (4)

I haven't received mine yet either:-) I will surely post pics as I go. Seems we've got at least three guys building this plane right now. Hopefully we can get a good thread going on it.

I was going to try a pull pull on the rudder and go with 2-56 h/w with metal clevises and dubro 4 screw horns (the black ones).

SJN

Im planning on building and using the stock hardware.....unless it realy stinks.

I have a Webra 91 P5 2sts engine for mine. I hope it is heavy enough so I wont have to add weight.....we will see..
Standard servos all around.
Eurokit air retracts, or springair......depends on what fits best

DragonHeart

Hi Guys

I have the GSP Zero and the GSP Spitfire to build soo i will keep a close eye on this 2

Im planning on using a Super Custom 120 FS in each

butlern

My Feedback: (15)

Hello,

I am approaching the end of my GSP spitfire assembly.

I think that plane is going to look great, I just hope that it flys well. I currently fly the H9 P-51 (60 size), which I though might be comparable to the spitfire with respect to take-off, flight, and landing characteristics. But we'll see soon enough... I should be able to get it out to our field this week (I need only to install wheel wells, cowl and canopy, and I'm waiting on the arrival of fuel dots).

I have installed an old YS120 air chamber, JR 770S PCM receiver, JR 531 servos, carbon push-rods, Dubro and Hayes hardware, and Spring Air retracts (#703) with 3/8!QUOT! oleos (#152). The retract installation was daunting at first, but once I got it started it turned out to be no big deal. I had to modify the oleos so they canter forward when deployed. And I also needed to modify the wing a little. However, this really only entailed cutting away some of a wing rib to accommodate the mechanism and adding several balsa, plywood, and hardwood gussets to strengthen the area. I have taken a few photos during the course of my assembly. I can email them to you if you're interested. I can also take more photos if there is an aspect or a step that is of particular interest to you.

Keep me posted on your progress, Dragonheart, SJN and hgiles. I will let you know how mine flys later this week (weather and time permitting).

Richard L.

My Feedback: (24)

* [link=http://www.whitetyphoon.com/rc/gsp_spit_show_pass.mpg]Show Pass[/link]

* [link=http://www.whitetyphoon.com/rc/gsp_spit_figure_8.mpg]Figure 8 at half throttle[/link]

DragonHeart

Nice vido clips, engine sounds great

SJN

engine sounds realy great!!

what engine and muffler ?

Richard L.

My Feedback: (24)

Engine is a YS 91FZ with a straight pipe (no muffler). This engine puts out plenty of power for this Spit.

I originally had a Slimline inverted Pitts, but it vibrated loose, and as a result, some material around the muffler mounting flange got removed.

SJN

Hmm...sory for misleading you guys, but I recieved a zero today instead.

When I orderen my spitfire in germany, He said they wernt in stock....written in german.
So I wrote back in english if he had a Hurricane og Zero instead. I got no answer, so I assumed he would still send me the spit.
Well....now I have a beutiful zero. Ill start another thread.

butlern

My Feedback: (15)

Richard,

The pictures and videos look great! Congratulations!

I have a few questions for you: Are you finding that the engine gets appropriate cooling airflow? Looks like you didn't cut much of the cowl away. Are you finding any cracks in the fiberglass fuse (behind the firewall) due to engine torque? I reinforced mine with some large triangle stock balsa, but I'm still a little worried about the torque and power of the YS 120 AC that I've bolted on to this plane. Throttle management, I suppose.

Also, How did you build up the wheel wells? It's hard to see from your photo, but it looks like you've used balsa sheeting to line the inside of the wing. Correct? I would be very interested to see how you worked that out aspect, given you've gone with oleos and (I presume) larger wheels, as I have. I was hoping to find some larger ABS molded wells that I could simply drop in, and someone was kind enough to directly towards Bob Dively Models, but their online catalogue shows no pictures and they have not yet responded to my question-filled email. I'm still looking for an easy solution to my wheel well problems.

Looking forward to your response, and a picture of your wheel wells if you're able to provide a shot.

Regards,

Noah

Richard L.

My Feedback: (24)

The engine gets plenty of cooling airflow. I have more than 1" square air inlet in front of the cylinder head and more than 2" square air outlet area:



In addition to the air exit hole at the bottom of the cowl, the rear of my exhaust stack is opened up on each side to allow hot air to escape.

I did not find any cracks in the fiberglass fuse behind the firewall due to engine torque.

I enlarged the wheel openings out to 4" diameter to accept 3-3/4" diameter wheels. I did not line the wheel well. I just used thin balsa sheeting to close off any holes, fuel proof the wheel wells with thin epoxy, and then painted them in gray. You can use balsa to sheet the wheel wells. Just spray some water/ammonia mix onto 1/16" or 1/32" balsa sheeting and bend it to form the wall of the wheel well openings.

hgiles

My Feedback: (4)

Received my Spitfire in the mail yesterday. What a huge box!! I thought someone left a refrigerator in my foyer! Packaged nicely and everything was undamaged. Bought the plane for $255 ($220 + $35) delivered. A great deal.

Workmanship and quality looks excellent. Nothing beats the real paint!! Fiberglass fuse and cowl. Panel lines and rivet detail is all there! I may try to accentuate them a little with some black paint. Decal sheet looks good... Pictures do not do this plane any justice!

Instructions are a little sketchy, I think I will manage. Hardware looks adequate. Many rods have z bends already in them. I will go ahead and use the provided hardware unless something changes my mind during the build.
Instruction give no real indication as to how to do pneumatics. This is my first cut at retracts of any kind so I am playing it by ear. My retracts haven't come yet, though.

Will keep you posted.

SJN

Show us some pictures!!

butlern

My Feedback: (15)

Here are some photos (finally)

butlern

My Feedback: (15)

And a few others...

I still have not had an opportunity to finish off the wheel wells. Beyond that, I only have to put a hole in the cowl for the glow driver, apply the decals and then it should be ready to fly.

SJN

Looks great!

I have to get one of those too :-)

DragonHeart

Hey butlern

Looks good i have one and wondered what retracts are you using ? (Make and Size ???) as i need to get some........... and how easy / hard is the installation of these ???? also what size alli spinner r u using ?

Many Thx

butlern

My Feedback: (15)

DragonHeart,

I posted most of that info a while ago in this same thread... But, since you ask, I used Spring Air 703 retracts with 3/8 inch diameter oleos/struts (also from Spring Air). The whole deal was just under $200. As I mentioned earlier, the installation was not hard, it just required a bit of cutting to create enough space for the mechanism. I also added some blocking to reinforce the spars and the area surrounding the rib that was trimmed. I can take some better photos of this detail and post them here if you would like.

The spinner is not really correct for the Spitfire (it's a 3 1/2 inch, Tru-Turn, 3-slot, P-51 spinner). But the plane itself is not really correct either. The prop is Master Airscrew 14x7 3-blade.

Let me know if you want details on the installation.

Regards,

Noah

BlueMax3

My Feedback: (1)

Noah,

Nice job on the spit. The gear installation looks clean. I notice some other nice looking planes in the background. Did you bend the oleo struts forward so that the strut and wheel line up in the slot and wheel well? If so, how did you do it? Also, since you ordered both the Spring Air retract and strut, did the strut fit right into the retract?

I will also be curious to know how your balancing works out and whether you have to add weight to the nose or not.

Thanks,

Travis

butlern

My Feedback: (15)

Travis,

I had a metal worker (in a surgical instrument shop within the hospital where I work) bend the oleos on a jig (at about 11 degrees, I think, I'll have to find my sketch). There was no collapse of the steel tubing. It worked very well!

My approach was to first install the retract mechanism then determine how much to bend the oleos in order for them to align with the center of the pre-cut wheel well. At that time I also determined where to place the bend along the length of the oleo. Next, after the bend was made, I cut the oleo to length (small pipe cutter worked wonders) so that the center of the axle shaft was in the center of the pre-cut wheel well. I used larger wheels, too, so I enlarged the wells to accommodate. Fitting the oleo into the housing was not easy. In fact, you'll have to remove all of the paint/finish on the oleo before you 'll even get close. It took a pair of spreaders carefully placed in the slot of the aluminum housing, coupled with some gentle force, for me to get the oleos to seat themselves in the retract mechanism. It can be done, though!! So don't lose hope, if you've tried and failed thus far.

As far as balancing, the plane was dead on 120mm (they recommend 120-130mm from the leading edge). I was surprised, as I added an extra servo for the gear valve, the air cylinder, bracket for the cylinder, and the push-rod guides behind the CG. I guess I can attribute that to the big YS120 AC that I bolted on the front. The spinner back-plate adds weight, too, I suppose. In all, the plane came out at 10.5 lbs. Now I have yet to fuel proof and finish off the wheel wells with a bit more balsa/epoxy/CA, and of course I'll have to re-balance one the plane is fully finished, but I don't think that it'll be anything beyond a minor shift in battery placement.

Noah

Pete850

Hi Chaps,

Do any of you have trouble with a nose-over tendency on landing?

I find that once the mains are on the deck it just wants to tip on its nose. My rocker cover is in danger of wearing through at this rate.

FYI I have an ASP 1.20 4-st throwing a 15x8.

Cheers

Pete

DragonHeart

Hi Pete,

Well im in the same boat as you i would probably say nearly everytime it noses over, thankfully not totally over just the spinner goes in a bit

Your not alone