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-   -   Building a Phil Kraft Kwik-Fli Mark III (http://www.rcuniverse.com/forum/classic-rc-pattern-flying-379/7117134-building-phil-kraft-kwik-fli-mark-iii.html)

captainv24 03-10-2008 02:01 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-01-25)

I had a day off that day, so I made serious progress om the fuselage...

Boeing727 03-10-2008 06:05 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
I just test flew my Kwik-Fli 3 -- constructed from Top Flite drawings .......
After all these years I figured it was time to find out what Kraft had hidden in that rather vanilla design ------
The wings were jig built , and the remainder of the project was a compilation of info gathered from the TF drawings as well as magazine plans from that era....
Balance was right on the money with no ballast -- powered by a Webra Blackhead ...JR radio....the only deviation from original was to use two servos for independant aileron drive as per modern practice.

This bird flew with no trim.....and it was immediately obvious that good ole Phil knew what he was doing.
It is a darned nice flyer and no apparent vices.......you are going to enjoy it !!!

If I knew how to post a picture , you'd have it !!

captainv24 03-11-2008 01:48 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 

Quote:

ORIGINAL: Boeing727
If I knew how to post a picture , you'd have it !!
When you post a message, check out the 'Click here to upload images and files!' link below the field you use to type your message...

Boeing727 03-11-2008 06:02 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)



OK -- got your assistance and here is the pic !

This model is pretty much to Kraft's design specs..no mods throughout ....................and it flies extremely well !

Stay with the build -- you'll like it !


kestrel0222 03-18-2008 04:50 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Nice looking Kwik-Fli III ! I have always wanted to build one of these, but never got around to it. I see that I can order these plans from Top-Flite, are all the patterns that I will need be on these plans (wing ribs, formers...)?

Thanks,

Boeing727 03-21-2008 03:59 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Tom-

I worked my Kwik-Fli effort from both the Top Flite and M.A.N. drawings ....
The wing is constant chord....consequently all of the ribs are the same except for gear blocks and other obvious issues.
The fuse has a minimum of bulheads , all easily developed from the side and top views on the plans.
The balance of the model is no big deal.

As previously noted (someplace !) ....my only change was to go with Top Flites version for the wings -- that is: 3/32 skins. I then decided to build the fuse with
one continuous sheet side ...no stringers and open frame.....I felt that weight saved was not worth the jigging in using Kraft's system ....
my model came in at slightly more than 7 pounds and balanced exactly on the published CG....

It's a nice flyer and an easy build.


kestrel0222 03-21-2008 04:41 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Thanks for the info. I have since found a set of CAD plans of the web. It looks like a very easy build to me. I have built many planes over the past 30 + years, from both kit and from scratch. I do agree with you in regards to the fuse sides and the wing sheeting. This looks like it will be a lot of fun!!! Can't wait to get started.:D

captainv24 03-21-2008 07:00 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Quote:

ORIGINAL: kestrel0222

Thanks for the info. I have since found a set of CAD plans of the web. It looks like a very easy build to me. I have built many planes over the past 30 + years, from both kit and from scratch. I do agree with you in regards to the fuse sides and the wing sheeting. This looks like it will be a lot of fun!!! Can't wait to get started.:D
Did you see my first post in this thread?
It has a link to a set of CAD drawings. Also, the creator of these drawings is active on this forum (username 'tweedy'). He has been very helpful to me.

I am using that set of CAD drawings and even though this is only the second plane I'm building (the first one was a kit), the drawings contain enough information to figure out all the bits and parts.

Combined with some help from tweedy and pictures on the internet of other people building the Kwik-Fly, I think I'll be able to build the Kwik-Fly.

Success!

captainv24 03-25-2008 01:59 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
(original date: 2008-01-29)
This weekend I attached to top plank on the fuselage and built two elevators.

I have put every part I have on the scales and guessed the rest. The result (with 15% unknown) is between 2500 and 2600 grams. (5.5 and 5.7 pounds).

captainv24 03-25-2008 02:01 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-01-29)

And some pictures...

captainv24 03-25-2008 02:09 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
(original date: 2008-01-29)
My weight calculation changed a bit:

Code:

Spinner                      70
 RX battery                  119
 Front LG and wheel          92  (edit)
 Fueltank                    49
 Switch                      24
 Wheels(2x)                  49
 Servo 3151 (4x)            174
 Servo 677 (1x)              35
 Voltage meter                5
 Wheel collars                14
 Prop                        20
 RX                          30
 Engine+muffler              489  (edit)
 Fuselage (at this point)    303
 Elevator (fixed)            47
 Elevator (moving parts)      23 (guess)
 Fin                          47 (guess)
 Rudder                      23 (guess)
 Wing                        452
 Ailerons (2x)                39
 Sullivan blue(2x)            45
 Sullivan red(2x)            34
 Wing 'rods'                  11
 LG wire                    102
 
 Margin (15%)                345
 
 Total                      2642

So I'm up to 2650 grams by now (5.84 pounds). Still, I have a 15% margin, so I'm not getting nervous yet...

captainv24 03-25-2008 02:11 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-02-10)

I have been working on firewall, engine support and front wheel support.
The back plate of the engine will be attached to an aluminium plate attached to the firewall.

captainv24 03-25-2008 02:18 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-02-18)

In the mean while I bought a second hand engine. An OS Max 50SX. I turns out the, opposed to my OS Max 46 AX, the needle is fixed to the back plate of the engine. On my 46 AX it is removable.

In the original thread several suggestions were made to remedy this situation. Such as:
[ul][*] Buying a backplate from the 50-SXH without the needle[*] Changing the firewall to accomodate the needle[*] Don't use the 50SX in the Kwik-Fli, but the 46 AX.[*] Just remove the needle from the backlate.
[/ul]

In the end I just removed the needle from the backplate.

NM2K 03-25-2008 03:02 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Or obtain a K&B .61 which will be as strong, or stronger than the two OS engines you have mentioned, and probably no heavier. Especially if you buy a new one from Clarence Lee with the PDP modification. Plus, it will be better matched era-wise.


Ed Cregger

captainv24 03-25-2008 03:15 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-02-somewhere)

I have reinforced the back of the fuselage with 0.6 mm plywood. According to Richard Browning this is a known weak spot in the Kwik-Fly, so I reinforced that spot.

I built a fin and a rudder. I created some notches for a firmer connection to the fuselage than the suggested 'glue on'.

captainv24 03-25-2008 10:10 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-03-24)

About one and a half week ago we had some nice weather. I used this opportunity to sand the fuselage to the right shape. I used some paperboards with the correct shape cut out, to check my work.


captainv24 03-25-2008 10:16 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-03-24)
A backlog of what I have done recently:
[ul][*] I have removed my needle from my engine[*] Fit my canopy to the fuselage.[*] Started fitting hinges to the elevator[*] Fitted some sullivan cables and made hole in the formes to accomodate the sullivan cables.
[/ul]

captainv24 03-25-2008 10:19 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
1 Attachment(s)
(original date: 2008-03-24)

As can be soon on previous pictures, I created a hatch for my fueltank from a block of balse (2 actually). Both the top and bottom have been shaped. Small spars prevent it from moving sideways.

Currently I'm building the nose. I will be on vacation the next weeks => not much progres...



WEDJ 03-25-2008 10:34 AM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Nice canopy fit. How did you do it? Sanpaper on the top block facing up and rub the canopy over it? Or some other, better, secret method?;)

captainv24 03-25-2008 12:08 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 

Quote:

ORIGINAL: WEDJ

Nice canopy fit. How did you do it? Sanpaper on the top block facing up and rub the canopy over it? Or some other, better, secret method?;)
Better and/or secret: don't know....
Other: yes.

I roughly cut the canopy to shape. Then made a small cut in the top of the fuselage. The canopy fits in this cut. About 1-2mm.

WEDJ 03-25-2008 12:41 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Oooohhhhhhhh

Good idea, thanks

UStik 03-25-2008 02:56 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Clever tricks! But is the grain orientation of fin and rudder also a trick? Never saw that...

franciscan 03-25-2008 04:03 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Hi Captain
You say you have reinforced your rear fuselage with 0.6mm ply. Can you describe this in more detail please. I have an uncovered fuselage from a Graupner kit which I could possibly modify if I can find the relevant details.

captainv24 03-25-2008 07:00 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Quote:

ORIGINAL: UStik

Clever tricks! But is the grain orientation of fin and rudder also a trick? Never saw that...
Oooh, forgot to mention:
The fin and rudder are built from 4mm balsa core with vertical grain, covered on both sides with 1,5 mm balsa with horizontal grain. It feels very strong. To save some weight I cut out some circles (approx 20%) from the middle layer.

It feels much stronger than a single 6mm sheet (the thickest I have on stock)

captainv24 03-25-2008 07:05 PM

RE: Building a Phil Kraft Kwik-Fli Mark III
 
Quote:

ORIGINAL: franciscan

Hi Captain
You say you have reinforced your rear fuselage with 0.6mm ply. Can you describe this in more detail please. I have an uncovered fuselage from a Graupner kit which I could possibly modify if I can find the relevant details.
Don't know if I will remember to upload a picture before I go on holiday, but this build log:
[link=http://www.fancyflying.150m.com/qwic_fly_iii_build.htm]Qwic fly III build log[/link] and especially [link=http://www.fancyflying.150m.com/fuselage%204.JPG]this picture on the right[/link] show how it is done.


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