issues with the P-47 kit #1001

[woundedbear]

Hi All,
I got my Guillows P-47 kit out last night and cut out the parts. When I compared the parts to the plan sheet, I found some issues with the kit. One small issue is the F2 wing angle blocks parts. I compared them to the one drawn on the plans sheet. The one on the plans sheet has a steeper angle than the die cut parts, of course, the die cut part is slightly larger than the one drawn on the plans sheet so it would be very easy to correct the angle of the die cut part. But which one is the correct one to use? The steeper angle of the one drawn on the plans sheet or the more shallow angled die cut parts? Getting the angle of inward tilt of the two F2 wing ribs is very important to aligning the fuselage to the wing.
Then there's the wood, for the most part, the balsa wood cut cleanly, but some of the kit wood was too soft for die cutting. In fact, some of the balsa wood sheets were contest weight AAA balsa wood! This works out well for building the tail surfaces and the die cut parts are a little long, and can be sanded to fit. However, the B parts (the formers) and the F parts (the wing ribs) have a lot of tear-out in between the notches for the 1/16'' x 1/16'' stringers. Now I am not complaining about the wood itself. if the parts had been laser cut instead of die cut the finished airplane would have been a great rubber powered scale model flyer.

[Bill Gaylord]

I generally make my own dihedral blocks, depending on how much I want at the wing tips. That type of die-cut part isn't very trustworthy, as you've seen. My P47 had one fuse former sheet which was some of the lightest wood I've ever seen, which obviously die-cut like crap. The sheet with the other formers was typical ironwood. It would be nice if they made some effort to match them a bit. For r/c, I laminated stringers across the fuse formers, as they were so light that they could easily split on the area where there is little wood, running in the cross-grain direction.

[Mitch]

Hi WB,

I agree with Bill use the plan and make your own angle blocks. Are you planning on flying this with rubber power? I am getting back to building and need to cover and fly my P-47 Beta 1. I'll work on that as you do your build. I built the skeleton as per plans as I was the Beta tester.

If I was building my own for FF rubber I would increase the diehedral. FAC rules allow maximum diehedral for the wing tip to be at the bottom of the canopy. I would approach that. If you do that then trim the wing brace to match the new angle you make. There is enough material in the brace to trim some off and make the angle you want. That is what I do.

I will fly with the model built to the plans, but use an adjustable nose block and a 12 inch prop and a lot of tan rubber.

Mitch

[woundedbear]

First of all, " a big thank you ", going out to Bill and Mitch for your advice. I was going to make my P-47 kit as my first Guillows RC conversion But since it has so much light (contest wood) in the kit I have decided to build it as a rubber powered free flight model. Any advice about lightning the plastic parts would be a great help also. But Bill you said you would laminate the stringers, this maybe a dumb question but what exactly do you mean by laminating the stringers? And to Mitch how high would you make the wing tips in inches above the center section for a free flight model of the P-47 kit? And back to Bill, I agree with you 100% on matching the wood in the kits. If die cutting is used the sheet balsa needs to be of sufficient hardness in order to be die cut in the first place. Now the wood in the laser cut Guillows kits I have bought so far has been a big improvement over the mixed bag-o-balsa that Guillows use to use in their kits. I think the balsa wood business is changing, I saw a video on some website where they were explaining how they are growing balsa trees in Ecuador. They are using tree farming technics, in much the same way they are planting fast-growing pines and popular trees here in North Carolina, to be used to manufacture chipboard or," OBS sheathing as they are calling it now", which is going to replace veneer type plywood. Maybe they could do something similar with balsa wood? Anything would be an improvement over the vinyl die cut stuff they replaced the light plywood that use to come in a Guillows kit. I have two real old # 2001 P-38 kits that have this type of three-ply plywood to make the firewalls for the old Cox glow engines. SIG sells something they call Italian Poplar lite ply, but it is only offered in 1/8 and 1/4-inch thick sheets. I wish it could be had in 1/32 and 1/16-inch thicknesses. But it's like a guy who is listed as an SIG Manufacturing dealer near Candor, N.C. Said to me," nobody builds anymore ". Everybody just buys a transmitter or receiver ready RC airplane or a RTF." you know a Ready to Fly foamy". Where is the pride in that? Well, Bill and Mitch look forward to hearing from you and anybody else who has any experience in building the Guillows P-47 model kit.

[Bill Gaylord]

What I did was glue stringers across the fuselage formers, at the top and bottom where they glue to the fuse keels and have the grain running in the weak direction, since 1/2 of them were so light that you could blow on them and break them off of the fuse keels. If I had been building it for rubber, I probably would have cut formers for the other side of the fuselage from contest grade wood, and not used the laminate reinforcement to reduce weight. I've also simply ran a thin wipe of glue across the top and bottom of formers for strengthening, in the weak cross-grain areas.

The vinyl stuff is cheesy. I remember building firewalls with that stuff and/or ply, which is really more than needed, even for electric r/c. I'll use some ply or hard balsa now, but generally not the entire firewall, since it's not needed. Maybe a hard balsa firewall with a ply insert or laminate, in the motor mounting area only. The only thing I've used it for in more recent times is cowl reinforcement, after cutting away most of the center area, to reduce weight. Obviously this is best done while the part is still in the parts sheet, since the stuff is fairly weak when the perimeter is reduced to 1/4" or less. If I remember correctly, the last time I did that, I had to tack glue the area I cutaway back in place, so that the part would hold shape during installation in the cowl. It was then glued into the cowl, with the tack glued center finally cut away. With rubber you may need the forward weight of parts like this, but even in that case I would probably build the firewall as light as practically possible, and then add ballast to the very front of the inner cowl. That additional 1" of moment arm counts for something, in reducing ballast.

The Guillow's P47 model looks promising for rubber flight, if you haven't seen this video before: https://www.youtube.com/watch?v=EjmXJ2XhiNc

[woundedbear]

a Gee Bill! That was certainly discouraging, is The Balsa Pilot a member of this forum? I sure hope he didn't give up after his experiences with the Guillows P-47 # 1001 kit. I will get one of these Guillows airplanes to fly if it is the last thing I ever do, this I vow! Why is it that you see some builds that turn put like the videos I saw and there were videos where the little airplanes just go (OOS) Out Of Sight. I saw a video of a Dude flying a 300 series Cessna 150 it stayed within the park he was flying it in. Then he sent it up one last time and it went (OOS) Out Of Site. There's some guy out of England who builds some really nice scale rubber powered model airplanes and they fly really good too! Well if all else fails I can always fly my Guillows Strato Streak I got some cotton swabs from my Doctors office they have some very hard dowel rods that are 2 millimeters in diameter. I took one of my extra fine cut needle files and made a fish mouth cut in the end of one then CA glued it into a T shape. While it was drying I took a 1/16th diameter drill bit and moved the motor mount forward by about 1 inch or so, this gave the prop enough slack when the rubber band motors were relaxed. I put two rows of knots in the rubber and let the prop go while pushing it up at about a 45-degree angle. It flew under power for only about 45 seconds, but it was really going up. Then as the rubber unwound it's little red prop started to freewheel, it got caught in a little updraft and I got an almost a 2-minute flight out of it. Some of the neighborhood kids came out to watch so I put them to work retrieving it for me. We all had a fun time, I just kept putting more winds into that blue rubber band, and the flights kept getting longer, then it wound up in a tree and the fun was over. But for just a little while me and those youngs had a real fun time. So if first you don't succeed, just have what fun you can and don't sweat the small stuff!

[Mitch]

Love those retracts. I think the flights looked promising, about all I would want to do in that field. I think we all need to re think our Rubber Motors. At least I do, I need to put a lot more rubber in these models and the 1000 series planes have room for it. I am not close to the 30 % weight mark. In the 400 series I do not know if I can fit in that much, but hope to approach that number in my new models.

Now that I am getting back to building (and finishing) I am curious to what your P-47 skeleton weighs. When you have all the components framed up I would like to know what you have.

[Bill Gaylord]

Love those retracts. I think the flights looked promising, about all I would want to do in that field. I think we all need to re think our Rubber Motors. At least I do, I need to put a lot more rubber in these models and the 1000 series planes have room for it. I am not close to the 30 % weight mark. In the 400 series I do not know if I can fit in that much, but hope to approach that number in my new models.

Now that I am getting back to building (and finishing) I am curious to what your P-47 skeleton weighs. When you have all the components framed up I would like to know what you have.

Thanks, that was one of those gotta have subjects, the Heston Phoenix by Eric Fearnley. The first time I saw the retracts that fold into the stub wing/wing struts, I thought it was the cleanest looking high wing monoplane I had ever seen. It's actually a really good flying model also.

I thought the P47 rubber flights looked promising also, simply in how "floaty" the model was. P47s have a generous wing and the video shows that weight isn't a real problem. Along the lines of your comments on improving rubber motors, the builder stated in the You Tube comments that he had a sub-par rubber motor, and with a bit more power and trimming it would have been a really nice flying model.

[Mitch]

That is exactly what I thought. I was concerned about these "heavy" Guillow kits, but the large ws of the 1000 series makes up for that... my Hellcat, she is one of my best flyers. The guys at WEST FAC 5 were surprised how light she was. And nothing exotic, it was Guillow wood and die cut. I just dropped half the wing ribs. The parts are so large I cut out lightening holes in the rest, but that was it. I need to cover my Beta P-47. Was planning for another build to be the N version (Larger wing yet) but that may not be necessary. My mechanic (helper at WESTFAC 5 Mass launch) said he felt I could have wound up the Hellcat more...and I still made it into the 2nd Round! I think when flying season here starts I will be getting in much larger motors! And The 1000 series I think will take 6 stands of rubber! And I use a 12 inch prop for these planes!

But on the other hand... you only need a modest flight in a ballpark size flying field! Enjoy it all!

Mitch