nickruss

I am trying to fit the frame stiffening kit to a DF V Ti pro, but the geometry just doesn't add up! The manual for the main assembly says to insert the main tubes ALL the way into the X-piece and the engine mount. I have done this, as you can see from the first photo below, however as the closeup shows, the left hand engine / stiffener node are way off!

Should the Draganflyer frame be symmetrical ie exactly the same length from the centre to the engines along each arm?

Of course I can pull out the main frame from an engine mount a little, but the engine mount is very prone to popping off then.

The rctoys.com website has a link to a PDF for fixing on the stiffening kit, but unfortunately this is dead, so I am asking anyone who is reading this forum for their advice.

Thanks in advance,

Nick

Sky High

It may be a bit skewed, not perfectly square, but only slightly. Make sure your stiffening rods are seating in the elbows as far as they can. They should all seat as in that closeup image. You may have to pull the motor mounts out a bit to get the stiffeners to fit. If the mounts have to be pulled out past what you feel is comfortable, you may have to shorten the stiffeners. I have found that there is a very small bit of skewing in several of the fittings like the circuit board fitting in the landing struts too. This thing is not perfectly squared as far as fittings but it is very close.

nickruss

Thanks for the lighting fast reply. But all main cross members and stiffening kit are inserted as far as they go into their seating elbows.

Can anyone measure the length of the cross members on their DF V for reference?

Sky High

I measured two rods and they were both 2 marks under 10 inches.

TheHindmost

With any luck, I'll be installing a frame stiffener within the next few days...I'll let you know if I run into the same issue.

I will say that given the various engineering challenges DFI has already overcome in producing this beautiful flier in the first place, you'd think a truly square frame would be a no-brainer for them!

Will

intrim

the problem that i had when i installed the stiffing upgrade was when i went around and tightened each motor mount 1/2 turn each was when it got to the bottom or i should say when the two started to mate. since the screw is offset on one side and not perfectly on top of the strut. what started to happen was i couldnt get the motors to square up because on the bottom of the motor mount there is a little *** that sticks up more on some than others so i had to remove the kit and file all the mounts so they were the same height and be careful that when your done it is also square because it is that one surface spot that will determine if when everything is tight the motors will be in the correct position

michael

TheHindmost

I installed my frame stiffener today, no problems...It all fit Ok and everything is reasonably square.

From your picture (the overall shot, not the detail), it looks like your main rods are maybe not inserted into the cross-brace all the way? The north-south rod in your picture looks bowed, suggesting the stiffener is pulling on it. That shouldn't be happening, so if you haven't solved the problem yet, I'd disassemble the thing, make sure the rods are all the same length, and look for obstructions (manufacturing flash?) in the cross brace and motor mounts. Assuming everything checks out, just make absolutely sure all the main carbon rods are seated fully when you reassemble it, verifying their lengths to the center of the cross-brace if necessary, both before and after installing the motor mounts.

Will

Sky High

Yep, it's a real pain but loosening all bolts in each fitting (hub, struts and motor mounts) and readjusting is necessary to ensure the closest symmetry. It's like truing the spokes of a bike wheel, too much on one side affects the other. I also noticed that there is a definite bow of the north and south arms. That looks a bit excessive. All DFs that I have seen are not perfectly square as I stated earlier. They are more almost but not quite a diamond or rhombus. I had a problem where one rotor arm seemed a few millimeters too short for the stiffener elbow to fit without compressing and bowing the rotor arm. If it was put on that way it tended to try to force the motor mount off of the end of the arm which would be catastrophic. The fix was to loosen that arm at the hub and the landing strut and pull it out of the hub until it aligned with the hole in the stiffener elbow and it worked perfectly! There is much more rotor arm pushed in that hub than out at the motor mount so you need to always pull it out from the hub instead of the motor mount if you need to extend the length of the rotor arm. This means that the motor arm should always be completely inserted into the motor mount!

Greasetattoo

My Feedback: (3)

Get out the old dremel tool, and trim the stiffeners.
Then measure, from corner to corner and make sure your measurements are the same!
Problem solved!

Sky High

That is a good idea and a possbile fix but if you make them too short they're useless. I would adjust rotor arm length from the hub before I cut. By the way, will the Dremel easily make a clean cut or will it leave a frayed edge. I have one and didn't think of that. Thanks.

Greasetattoo

My Feedback: (3)

Dremel works great on carbon fiber!
I use the brown trim wheel!
A little sandpaper too!
Just don't breath the dust!

The rods can be bought at your local hobby stores too!

Greasetattoo

My Feedback: (3)

One other trick to use...
I learned this from my father...

Take one of the stiffners and rub it on your nose, next to your nostril...
Believe it or not...
The oils from your face/nose will make the stiffeners go in better!

Works for me!!!

Sky High

I've heard of elbow grease but not nose grease!

detroitdr

This week I installed a frame bracing on my DF 5 ti. I did have to loosen all the screws to make it fit. I also came up with a VERY CHEAP landing gear that I tested last night and it worked like a charm. I took pictures all along and will post here this weekend. Also I came up with a very good lighting system that works extermely well... again will post this weekend.

detroitdr

Sky High

detroitdr, check out Kuzer's custom landing gear.

www.rcuniverse.com/forum/fb.asp?m=4077543

detroitdr

Looks nice SkyHigh.... I'm home now so I'll upload my pictures...