Mein Duff

Good point on the engine install...the Hispano Suisa was gear driven and ended up in the middle I think, the Wosely Viper had a lower thrust line, or visa versa! However the install as you have it now is incorrect for any real engine mounted in the SE5 for "true scale" appearances.

Mein Duff

Actually with the rounded cowl top that would be the Hispano Suisa engine, the Wosely Viper was squared off at the top.
This also looks to be more like a SE5, not the SE5a with the longer radiator and deeper squarish jaw, but again this is Balsa USA sport scale.

vertical grimmace

My Feedback: (1)

I guess I was incorrect on the position of the prop, if this photo is an accurate example. (look like a replica) It still would seem the prop exit needs to move down.

Gungadin

Here is a good shot.

http://en.wikipedia.org/wiki/File:Ro..._-_Frame01.jpg

And another http://en.wikipedia.org/wiki/File:Se5McCudden.jpg

http://en.wikipedia.org/wiki/File:SE...r_memorial.jpg

MRadu

Thank you Vertical Grimmace,
My research tells me that the prop height is in the middle and if I rotate 180 it will be farther from center. I'll have to decide weather to leave it the way it is or lower it and have the motor hang below the cowling. However that will be for my next build thread.

Mein Duff

Michael, Post #28 shows the SE5a with the Wosely Viper...pretty much smack dab in the middle..also has the squarish top cowl. Actually yours, with the geared Hispano Suisa engine version, is just about right, more to the upper part ( as were all SE5's) before the SE5a's Wosely Vipers came out which definitely had a lower thrust line.
Just leave it, minor detail....more important is good building and straight wings

MRadu

Thanks Mein Duff, and all in regards to the SE5a or SE5.
I'll open a new thread when I get to the build of the plane. Then we all can re-visit the issue again.

Here what I have been doing on the Fokker D.VII
I have heard (from another that has the Fokker D.VII from Balsa USA) that his tail incidence was off and he had to fly with tons of down elevator! After further discussion I found out that he did not add any down thrust. The kit calls for down and right thrust (of which I'll do)! However, I still changed the tail incidence about 1/16". I also shifted the vertical stab to scale (see photos).
Let me know what you think as I can change it now.

MRadu

I have moved on to installing the throttle servo, made the servo tray for the tail surfaces and mounted the electronic ignition while waiting for discussions on my incidence changes.

FireBee

My Feedback: (34)

Awesome work.

I love the tail wheel solution. My D-7 will be modified to use this approach as my rubber coords came loose from the hook at the rudder post area.

For a better cowl radiator screen...use stainless steel mesh. Just go to a local office supply store and buy a the square black mesh trashcan. I use a dremel cut-off wheel to cut it down to shape and then add the two vertical bends it to match the cowl. Make a pttern from card stock first!!!. I have enough left over for 3 more cowls. Will post pics tuesday.

This allows better airflow than the radiator screens I got from Proctor. (too tight to let air through very well. I'm now using for my Hurricane radiator screen.


For the fuel filler. my friend used the radiator filler tube and cap as functional.

Gungadin

Michael

Many say to to add 3 degrees positive to the leading edge of the stab. From what I've read in other Balsa USA Fokker DVII threads, and talking to guys who have built and flown it this seems to be the solution.

MRadu

Thank you Gungadin,

I added a 1/16" balsa strip at the leading edge and removed that amount or more from the back. I hope this is enough. I don't want any more as I believe it will be to much and I'm sure it will remove the scale looks.

Do you think that is enough? Also later on I can modify the thrust angle if need be.

Gungadin

Michael

It may be enough. Can you measure stock VS your modification in degrees ? I believe builders who built the DVII stock per the plans, used the recomended engine down thrust setting, and still had a lot of down trim in their transmitter to fly level at half throttle. Full throttle is worse. So that is why the modification to the stab incidence. 3 degrees seems to fix the problem assuming other things like down thrust & wing incidence are per the plans.

jeffEE

My Feedback: (5)

I have flow the Balsa USA DVII for two seasons with the Saito 2.20. Great combo. Nice power to weight and sweeet sound. Have you thought about the amount of down thrust you might need to fly it level? Mine needed a LOT of down trim to fly level. Other build threads here have said the same thing. In the one I am building now, I put in down thrust and a few degrees of trim built into the tail surface. There is a big fly in during August in Wisconsin. Would be great to get all of these Fokkers together.

jeffEE

My Feedback: (5)

opps. never mind about the trim fix. I see that you have that covered.

vertical grimmace

My Feedback: (1)

I think my DVII flies fin without the trim but I also only have one degree of positive incidence in the top wing. So under power it does not want to climb as much. There are lots of places where the rigging of the wings, engine and stab can effect trim. It seems that there have been many different opinions. Mine climbs a little under power, but not like a trainer. I have about one degree of down trim all of the time in the stab. I think the amount you have added will be perfect.

One big time mod to make (I point this out in all of the BUSA threads) is to replace the main Axel with a 1/4" music wire. If you do not do this to start with, you will be doing it later. The stock axel is too light and will bend.

MRadu

Thank you Vertical Grimmace,
Yes I agree with you. The main axle is two small and the Fokker D.VII does not have any bungee shocks! I have plans on changing them out. I have an RC friend coming over this week and we are going to re-design / re-work the landing gear. Also have you noticed that the axle wing on the Balsa USA kit is way too slim? I'm going to build a new one from scratch. This will allow me to install the bungee into the design.

On the the positive incidence. I'm happy with what I have so far and will have to see what the out come is.

MRadu

JeffEE,
Thanks for the comments and the invite. I have been to the east coast for the Blue Max in Florida and the R/C event at Rhinebeck in New York. However, I have yet been able to get one of my planes to the event. It seems to be to hard or to costly. Any ideas?

MRadu

OK, Now here are some more progress photos.

I have place some guide / support for the control cables and temporarily placed in the cables. The crimps are just slid on for alignment issues. Also I have installed the servo tray rails and set the tray in and held it in with 5/16" servo screws.

The Receiver is just resting inside at the moment, however, the settings are now adjusted and ready. For example there are two channels for the two servos for elevators and two channels for the ailerons as well. This allows me to set each separately for things like the ability to have the UP of the ailerons to move higher the the DOWN on both sides.

vertical grimmace

My Feedback: (1)

On my gear and axel wing, I did scratch build mine as well. Everything. I made mine almost scale. The wing does need to be thicker to allow for travel of the axel. I want to mention though that I would NOT make your gear bungeed. I had a bungee on my triplane and my DVII for a long time and it gave me a lot of trouble. I am sure many will disagree, but I will tell you it performs much better stiff, with the 1/4" Axel. The other item is to pull the axel back in the middle so you create some toe-in. You may be able to accomodate this with the wing, but I have 2 spreader axels running the length of the wing, in front and back of the main axel. This was done to support the gear at the strut attachment. I pulled the axel back to the rear spreader and lashed it with wire and soldered it.
I built my axel wing to split in half. If you look at your documentation you will see these halves were held together with straps. I just used metal landing gear straps. It is nice to be able to have access to the gear for servicing. It will need service!
It may sound confusing, if you need pics I will see what I can do. I currently have the gear off the triplane as I am doing some serious maintenance to her. She is getting a new engine and smoke system.

MRadu

Thanks Vertical Grimmace,
Yes please add some detail photos. I'm looking for a better solution for this part of the plane. I too agree that having a design that could open for service is a must.

MRadu

Thanks Vertical Grimmace,
That is one nice Fokker. Would love to see much more detail of this plane! Thanks for the photo!

vertical grimmace

My Feedback: (1)

Here are some more

Mein Duff

Nice Job Vertical....she's a beauty! Just wondering what are the major areas where the Balsa USA 1/4 scale doesn't measure up to "true scale" appearance or outlines?
Also as to bungee or no bungee..I had a 1/4 DR1 with bungees and had no problems with the undercarriage, no "Toe In" either......I'm sure you have had your bad experiences but I've never regretted it on any Biplane I've had, you can always tighten them up if need be.
Also wondering where you got your lozenge material, was it stick on or doped?

vertical grimmace

My Feedback: (1)

Well, I have not really compared all of the details on the BUSA for scale, but I use mine for competition. The 3 view that I have has been scoring almost perfect in outline. I have some issues with the nose and the undercarriage are too wide and maybe a little forward.
The gear is one of those things you set up until it works for you, and I settled on what I have now. It just seems if the plane starts to go one way, it keeps going that way. If it is stiff to begin with, that keeps it from going that way in the first place!
The fabric is Glenn Torrence. Again, in my opinion, the best thing going. It is doped on, but is not that big a deal to apply. Not if you have experience with silkspan and dope. In the end it does not take that long, and is how the real plane was done. After 5 years, it is looking better and better.
The first pic is when it was brand new. The later pics you can see added trim colors and the fading and weathering of the fabric. I have been very pleased with this plane.

foodstick

One thing I have learned flying my D7, is that it will take off WAY early into a decent breeze. I have never been in any trouble with it on a calm day..But I flew it in a 10-12 mile an hour wind one time..scared me every takeoff ! It would just be starting to roll and bam ..it would catch me off guard and leap up and be flying so quickly..even under low power rollouts.. 46cc motor 22/8 prop...