Wid's Messerschmitt Bf 109 kit 505 (RC)

[WIDDOG]

First it sure is great to be back working on a Guillow's kit. Second I don't have much experience converting kits to RC. So this thread is kind of a intermediate skill level build. I choose kit 505 because I happened to have an unbuilt kit in stock. I am posting this build to keep the big topic board moving.
I decided to build the tail components out of Depron foam.

[woundedbear]

A foam tail of a Guillow's kit ! heresy ! heresy I say !

[WIDDOG]

Here is a foam/Balsa model mix.https://youtu.be/zuvH2nKaOTU .

[dirk gently]

Wow, what an amazing flight! And landing!

[WIDDOG]

The foam tails where easy to make. If this works out I am going write to Guillow's suggesting they add a small piece of Depron foam to their kits. To give modelers the option of making a foam tails.

[davidchoate]

I did an Rc conversion of the 505 109 a couple yrs ago. Good kit. Bad for RC though. No room in the fuselage. Balance, and too heavy. Typical Guillows problems. It looked great though. I won 2nd place in a contest at Hobby Town. I just started a FW 190 400 series. I only ever did the Zero and mustang from the 400 line. I must be able to use more reliable servos, and etc. Which means larger Planes. Even at 1/16 scale its small, and small is (in My experience) a real Challenge to make even into 3 channel RC.But They are cheap, and I learned a lot from them. I am just recently ( thanks to forums like this, and RC Groups) for the info. RC Groups is very crowded, and diverse. This Guillows Forum I can ask a question, and more times than not, have a good reply the next Day. David Lewis, and the other highly knowledgeable about aerodynamics espescially lately.

[WIDDOG]

Thanks for posting. Although I have gotten better at RC flying I'm still kind of new at it. I just happened to have this Messerschmitt kit in stock. The way I learn is to drive right into the deep end. Although I'm very optimistic I look at this as more of a learning experience. I do listen to suggestions and appreciate them. I take the time to post so I can get better. You know some day I would like to be a experienced advanced modeler. I guess for now I have to work on it. The good is that I am having a ton of fun and I feel I am getting better with each build.

[zoomie]

The foam tails where easy to make. If this works out I am going write to Guillow's suggesting they add a small piece of Depron foam to their kits. To give modelers the option of making a foam tails.

One foam source is the Hefty brand picnic plates and clamshell boxes, they seem to be thinner (lighter) than other foam. And, they're often free from take-out restaurants.


Nice thing about foam tailfeathers is they make it quick & easy to experiment with smaller or larger configs. For smaller fin/rudders they can be trimmed down a little at a time with scissors. The fin/rudder on your 109 is probably fine as is, though.


zoomie

[WIDDOG]

Thanks Zoomie. I am finishing up the wings. I decided to make this build a FF rubber power instead of RC.

[WIDDOG]

I messed up the cowling that came with the kit by fitting it with a electric motor. I was able to refit it with a FF nose block. I actually feel that this nose block may be my personnel best.

[WIDDOG]

https://youtu.be/KqkX96anx-Q Even though this peanut fw 190 is not a Guillow's kit it has me motivated on this build. I have not had much success with the 500's in the past. However, I am thinking that if I can keep the weight down enough maybe it will fly well. I seem to be hooked on the 500's again.

[WIDDOG]

I did finish the model with an AUW of 35 grams. I've heard that for a 500 Series kit to fly well it should be no heaver than 33 grams. Anyway my model did not fly very well. I'm getting maybe 15 sec flights. It just seems that it is just too heavy. To be honest I could have applied lightening techniques. I didn't and I'm not getting very good flights.

[David Lewis]

Sorry to hear that. I'm becoming convinced that as wing area goes down, weight must go down at an even faster rate in order to get decent performance. That would mean these smaller models require a higher level of modeling skill. Here are some suggestions:

1. The width of keels, formers and tail outlines can be reduced and still leave plenty of strength.
2. Cutting the parts out of contest balsa will help.
3. Side keels, 1/8"x1/4" spars, and other lightly stressed members can be omitted.
4. Switch to a high lift airfoil.
5. Increase horizontal stabilizer area and move CG back.
6. Increase the nose chord (reduces nose ballast) and wing area at the cost of scale fidelity.

[WIDDOG]

Thanks David, I now agree with your tips. With my model I even tried over stuffing it with rubber. It definitely gave me more power to lift the model. Hoever, I noticed that my tail surfaces where too small to handle the increased speed. Next time I will try your tips. I have to say that I have had better luck with the 900 series kits. I am currently building a Walnut Scale laser cut kit. I am interested in seeing how a slightly larger model flies.

[Mitch]

WD,

I am curious on how your nose block fits into the cowling? Is it keyed to only enter one way?

Most FACers would not use the plastic front end. I do, but it is not structural. Just the finished skin over the real nose block underneath. I think it is importnat to have it lock in somehow in one position. From there you can make adjustments to the angle of thrust.

Mitch