Pointers for new-to-scale builder
 

Hi all. I know that there are always "new guys" around asking dumb questions... and I may just be one of them. But, I have some questions.

I have been in RC Airplanes for a full year now. Built two kits (both from Great Planes) a PT-40, and an UltraSport 40. Although I still really enjoy both planes, I am now facing about 6 months of cold, and have a winter project ahead of me. I have always had great respect for the Spitfire, and a few months ago I picked up a Great Planes Spitfire-40 kit. This kit is discontinued now, but I got it second hand NIB.

I am somewhat constrained financially ... I will have to compromise scale for cost at some level, but that limit is still somewhat undefined.

The kit most closely resembles the MkIX, and I would like to try as much as financially possible to make it scale.
This is where I need help....

1. The kit is designed for monokote like covering, with many lightening holes, and unsheeted wing surfaces. I do not think a plastic covering will be good enough for me. I was hoping to learn how to paint with this kit. What are my alternatives? I can sheet all open areas, I could learn to fiberglass, or is there another type of covering that would be a good base for paint? I am willing to go the compressor painting road, but need to know in advance whether I should be aiming for a full sheeting, or an alternate covering. I have never glassed before, and am hoping to avoid that route on this kit... glassing can be learned on another occasion. The Rudder was material in the original, and I will try to go for that.

2. The kit reverses the operation of the retracts ... The wheels retract in to the belly of the fuse, rather than "outwards" into the wing. This obviously makes the kit more stable on the ground ... but ... this to me is a big deviation from scale. Any suggestions/opinions on whether I should use the kit's suggested mechanism, or bash in the "real" operation? While I am on the retracts, anyone with suggestions on how to find scale main gear? Remember it is a 40 size plane. Much of the detail of the reteracts are hidden behind the doors, so I guess I could go a long way just by figuring out how to put doors on it...

I guess that is a good start with my questions. I need to know what wheel structure I am going to have, and how I am going to finnish the model before I start, so opinions/sugegstions on these would be good.

Thanks in advance

gus

P.S. It is apparent that I have the kit already, so I want get this one "good enough". I will in future be looking to go for larger scale. I need this kit to be a good starting point for me to learn the techniques required in the larger scale environments.

RE: Pointers for new-to-scale builder
 

Scaling out this kit would be a bit much for even the most adhearent scale modeler.
This model was intended to give one the appearance of a Spitfire in the air while giving it the flight characteristics of a sport model. I'm not going to discourage you from trying some of the mods that you talked about, but think them out carefully.
I'd leave the the retact set up the way it is. If it is the first time working with retracts it will be easier.
As far as painting goes it is worth a try. Just remember to keep it light. Fiber glassing could get a bit heavy. You might consider using silkspan and dope. There are other techniques so if anyone else has a suggestion lets hear it.
There are quite a few books out there that discuss finishing options. Some of them are by Harry Higley. There are others and there worth checking out and purchasing for your work shop.
Good luck and have fun !!! [&:]

RE: Pointers for new-to-scale builder
 

Monokote makes a "paintable clear" covering (or at least they used to) which would be an alternative if you have your heart set on painting this plane. I used it once on the open framework tail surfaces of a Sig Astro Hog. I used Formula U polyurethane paint (white) which looked good and seemed to last pretty well.

Are you aware that Monokote makes "flat" colors? Flat Olive Drab and Flat Tan would look good together in a camo pattern. Flat Gray would also look good in place of the Tan. I used the flat Monokote on a Great Planes F-4, patterned after the boxtop picture, and it looked really good.

RE: Pointers for new-to-scale builder
 

gus, you have a project that can go two ways, either very difficult or an average build with some attention to detail. As others have said you have a sport kit not intended to be scale. You can build the plane, gain the experience. paint the plastic covering and have fun. Or you can slave over this plane, trying to make it more scale and in the end.. its still not that scale. Something that is invaluable but often NEGLECTED by new and even some seasoned scale builders are RESOURCES. By that I mean..learn what the plane really looks like, inside and out. Study about the plane and its different models from several sources. Sucessfull Scale modeling starts out with (hopefully) Knowledge of the subject. After you have learned what you expect at the end of your building process you'll make wiser choices at the beginning (Kit/plan) selection stage.
Techniques are something you will continue to learn even after you have build several planes. I would limit myself (for this project) to building a very neat, accurate kit. Paint it in authentic colors complete with markings and fly it. That's plenty for a first project. hope this helps BobH.

RE: Pointers for new-to-scale builder
 

I would leave the retracts alone and consider covering the model with Super Shrink Coverite, then paint directly over that. It's lightweight, takes paint well, and one coat usually fills the weave of the cloth. It's advantage over silkspan and dope is that it's applied like monokote, without any real need for special surface prep (although a light coat of Balsarite may help). I also find it to be nore robust then Monokote.

RE: Pointers for new-to-scale builder
 

Thanks all for the input so far...

I think I took a couple of steps more than I should have. My goal for this kit is to be a "scale trainer". I want to use this kit as much as possible to learn techniques that can be applied to a more scale project. One of the real differences between scale and "normal" RC planes is the paintwork. Good paintwork means that most other scale deficiencies are overlooked. I really want to get this kit into a state where I can use it as a learning curve for painting. It is a stepping stone that is not going to be a disaster if I mess up.

Now, because the design intent of this kit is to be covered with monocote, I will need to make some alterations in the build to cater for the change-of-plans. But, I do not know which direction to take. Do good scale projects "milestone" at a fully sheeted, covered-in-special-fabric, or "glassed" stage. If I could get some idea as to where I should be heading I can at least start glueing some pieces together ;-)

I am prepared to work hard to get the kit into a state where I can concentrate on the finer details. Most of the deficiencies in the kit itself are in the cosmetics - cowl shape, antennae, cannon, cannon-fairing, radiators/oil-coolers, etc. I can tackle those as sub-projects. But I can not even start the kit unless I have an idea of what it should look like before I paint. The retract orientation is relatively inconsequential I guess. I know that some things will have to be sacrificed to keep the plane functional.

One of my challenges is that I have not seen many good scale planes, and have never had quality time with the builders of those planes to learn some techniques... hence my posting.

Maybe if someone could point me to some pictures of a plane that is prepared for painting I can get a better idea of where I should be heading.

As for the kit choice ... I chose it only partly from an "emotional" perspective. I am of British descent, so the spitfire is the "hero" of the air-war for me. Also, I saw it come available as a NIB kit, so I took it. I had done some research before. I knew it was intended as a more sport plane, rather than scale, but the I though would be in my favour being an intermediate pilot myself (this will be my third plane- the other two are still flying strong, a trainer and an UltraSport+).

Anyways, thanks to all so far for their input. As for the books... well, XMas is round the corner ... but I am sort of hoping for a RCV60 as well...

gus

RE: Pointers for new-to-scale builder
 

gus, there are several building threads on the warbirds forum that show various stages of construction. Go there and look for construction photos. If you want to pant and simulate the metal finish of the spit then you will have to add balsa sheet to the open structures. From there you can fiberglass and then paint. Along with adding surface detail of panel lines and fasteners etc. BobH.

RE: Pointers for new-to-scale builder
 

Gus,

Dave Platt sells a whole series of videotapes (and now DVDs) on building, detailing and finishing scale planes. They are full of wonderful and well presented information, and I would strongly advise you to get them -- if you email him he'll probably advise you on which ones to get first.

I built the GP Spit 40 a couple of years ago, for much the same reasons you are, and had a lot of the same questions. Here are a few pointers:

- I powered it with the RCV-60. Great engine, reliable, will swing a scale prop. Pay attention to their suggestions about air ducting for cooling, though... I ended up opening the exhaust stack moldings with a dremel tool for an air exit and adding a hole in the bottom for the same purpose. An air duct is easy to build out of lithoplate or even glassed card stock.

- I put Robart robo-struts on the retracts to make them look prettier. Ended up taking them out because the retract servo couldn't cope with the added weight. This meant, aside from the wasted money on the Robostruts, that I had to re-sheet the whole strut area to accomodate the shape of the struts -- BTW, I used Great Planes' 40-sized mechanicals ans they worked OK.

- Still on the retracts, save yourself a lot of grief and move them with 4-40 pushrods, the 2-56 will bend and cause all sorts of problems while you tweak them to work well. Also, leave plenty of space in the wheel and strut wells: the struts WILL bend, and you don't want them to stall the servo or rip out some sheeting.

- I covered it with OZ Cover, and painted it with Nelson paint. OZ Cover is the most amazing stuff, can't recommend it highly enough. Nelson paint works, but has a learning curve: if you screw up (and everybody does while they're learning) it won't stick worth a darn, and sanding it off heatshrink covering is not a pleasant experience.

My plane had a high wing loading (sorry I can't be more specific: I don't have a scale, so I didn't weigh it). I didn't sheet any open spaces, or put in any extra scale details except for the radio mast aft of the cockpit, but it still had a very mean way of throwing a wing when I let it slow down. Most reviews I've read about this speak about this personality trait as well -- my guess is that's one of the reasons why it was so quickly discontinued. It has to be flown in, not floated in -- mine bought the farm when it snapped on final about 6 feet high after about 20 flights.

I would concentrate on building straight and light. Use this project to learn about retracts and engine cooling, get your painting skills up to speed and learn how to fly a high-wing-loading model. You'll do better to save some learning for your next project, otherwise you may well end up with an unfliable brick.

Good luck and enjoy your project!

Juan M. Villaveces

RE: Pointers for new-to-scale builder
 

Thanks Condor...

That makes perfect sense. I was hoping to bump into someone who had personal experience with the craft. You are the first.

I think you did with your spit pretty much exactly what I was hoping to do with mine. Aim to concenterate on a few discrete build componenets and make them scale. I was aiming for the painting, retracts, antennae, guns, and cowl. I will scale back my ambitions for the retracts.....

Otherwise, I am hoping achieve the same as you.

One other question. I was looking to use the RCV60 as well. I know that scale is scale and all that, but this is one area where I feel that as an intermediate pilot, having some available oomph in a sticky situation may save my plane. Did you feel that the 60 was flying the plane with a bit of oomph to spare? Should I look for a notch up, or maybe even a notch down?

As for everything else, I think I will do as other have suggested. Concentrate on a really neat, clean, and precise build. cover with a paintable material, and paint. I think I am going to try to fashion my own cowling somehow... I have done it before. Use retracts of some nature, and I think I have to install some of the more prominant but absent features, like the radiator/oil cooler.

Thanks all for your valuable assistance.

gus

RE: Pointers for new-to-scale builder
 

I have not built the GP spitfire but I have done several smaller planes in fabric and paint that worked pretty well. I would suggest building like you were going to cover with moneykote, no extra sheeting. This keeps it reasonably light or at least within its recommended weight range. Cover it in a fabric then paint it with spray paint, (I dont recommend luster kote for color), something like 21st century or rustoleum. Rustoluem is what I have used many times and I've seen camo colors at the hardware store recently. I would suggest clear coating the rustoleum with luster kote, thats the only luster kote I would use. 21st century is a pretty good paint, much finer pigment than luster kote and rustoleum. I dont know about mechanical retracts but the previous suggestions make sense to me. I can tell you from experience that a small plane built heavy is gonna be pretty disappointing. Dont even consider glass on a .40 sized. Im usually leary about doing any glass work on 60 sized planes, thats an acquired skill that comes with experience. It can be done though. If you build to sport scale standards and concentrate on the paint job I think you'll still be pretty satisfied with the outcome and still have a decent flyer.
Just my opinion.
Edwin

RE: Pointers for new-to-scale builder
 

Gus,

The RCV-60 was plenty of "urge" as the Brits say, even considering the fact thet I fly at 8000 ft ASL, so at nearer to sea level it should be even better. The feeling of that much torque is something one needs to get used to, but it has more than enough power to get out of trouble; I'd say it's a bit less power than a regular .70 4-stroke at a lot less weight.

If you do a search in the engine forum, you may find an exchange between myself, Otto Kudrna, who distributes RCV in the States, and Ann Marie Cross, who used to head customer support at Great Planes. I was asking whether to go with the .90, and they were both very emphatic about what a terrible idea that was.

Good luck,

Juan M. Villaveces

RE: Pointers for new-to-scale builder
 

IF you feel you want to sheet the open bay areas, I would suggest using 1/32" balsa (or 4 - 6 lb grade 1/16"). MAKE SURE IT IS SECURELY ATTACHED TO THE RIBS and use a .5 - .75 oz fiberglass cloth applied with MinWax PolyCrilic (SP ?). It is the water based polyurethane. Use just enough to stick it to the wood and let it dry (too much and you MAY warp the thin sheeting). Then give it a second thin coat. After it is dry, sand with 320 - 400 wet/dry doing it wet. Make sure you get the residue off, and when dry give it another coat of the poly, but this time mix micro baloons in with it. This will fill the weave of the fiberglass. Sand lightly with 320 - 400 wet/dry wet. Give it a final coat of the straight poly, a little heavier this time though. When dry, do the 320 - 400 bit again.

I would then spray a LIGHT coat of primer/filler (automotive type) and when dry sand it off to show any high/low spots. Repeat the primer/filler/sanding untill satisfied with the surface. BE CAREFUL YOU DO NOT SAND THROUGH THE POLYURETHANE AND FIBERGLASS. Clean the surface with rubbing alcohol and spray it with latex.

On a 40 - 60 size plane, this "covering" treatment will add about 6 - 10 oz to the weight (depending on amount of primer/filler used and number of coats of paint) of the plane, but will also provide a HARD, DENT RESISTENT SURFACE. Let the latex "cure" about 2 weeks (depending on humidity and temperature) and clear coat with waterbase polyurethane (fuel resistant to 10 - 15% nitro) OR LusterKote (or the UltraCote clear).

I am in the process of doing a SkyShark Hawker Tempest this way. It has mechanical retracts and will be powered by a TT 61. I anticipate my final weight at 6 3/4 - 7 1/4 lbs.

As far as the engine goes, that should be determined by your final weight. While there are exceptions, the GENERAL RULE is go 1/3 larger when going to a 4 stroke (i.e. plane calls for a 60 2 stroke, use a 90 4 stroke).

I hope this will help.

RE: Pointers for new-to-scale builder
 

Gus,

I have used the paint over clear monokote and it works very well (I did not sheet the wing). Cover the entire plane with the monokote and then sand it to remove the gloss with 400 grit wet dry paper used wet. Be careful not to sand through the covering on sharp edges. It really is very easy. I then gave it a coat of ordinary automotive grey primer from a spray can. I painted mine with an airbrush using tole paints (such as Ceramcoat) thinned about 50% with water. Use many THIN coats. You can use your heat gun to help the drying process. Be aware that it looks like sh** at first. Keep at it it will get better. The advantage of the tole paints is that they are available in hundreds of shades and are quite cheap. After all the markings are on I give it a coat of satin clear polyurethane to fuelproof it. I've done several planes like this and the results are very good. Robart has plastic "Robostruts" that, although not functional, look great on warbirds without adding much weight. The cockpit can be detailed without any weight either. I did not put cannons or antennae on mine simply because they get broken off too frequently. By the way, my spitfire below was scratch-built, the wing from the 40 size Dynaflite Spitfire plans, and the fuse from a set of enlarged Guillow's Spitfire plans. (I didn't like the squarish Dynaflite fuse). It weighs 5 1/4 lbs, grooves very nicely at speed and lands at walking speed. It definitely is a floater.

Cheers!

Jollidude