Kit Review, Max Thrust Ruckus (Another Poly Project)

On its maiden the model took off straight and true and with a touch of elevator went up vertical!!! ... I throttled back to about 1/3 and it leveled out nicely, no aileron or rudder trim needed just yet, but I did have to trim the elevator for a nice steady circuit or 3.
I then throttled right back and trimmed for a beautiful glide with just 2 clicks of aileron and 2 clicks of elevator.
Here's where the fun began, I opened up the throttle again and once again it went vertical!!!! silly bloody model.
I've got a feeling it needs about 90 degrees down thrust, or maybe the ailerons are both just slightly in the down position so as to be acting like flaps???.... Possibly the angle of incidence isn't quite what it should be.
I'll check the down thrust first, when looking at it from the side it does look like it's got down thrust, but looking at that last picture it would appear that you can see quite a bit of the underside of the motor shaft, ...... it even looks like upthrust.
I'll sort it out as soon as I fix the undercarriage ... This is my next complaint.
I did a beautiful smooth landing on short grass but when I tried to taxi back to me the model just wanted to go in circles. I walked over to it an found one wheel was bent. I straightened it by hand, which was far too easy to do, and took off again.
The next landing was even better, and on the smooth road .... guess what, ... A bent bloody axle again!!
I took it back to the car and had a good look, the axles are a couple of very soft M3 bolts!!! ... I don't even think they are a decent hard steel, they look like aluminium .... and bend like it as well..... 2 more slight attempts to straighten it by hand and it just snapped off.
Here's a picture, I could drill the wheel hubs out and fit wider bolts, M4 would be easy, M5 are even possible. I'll have a look in my junk first and see if I've got some proper axles.



Pol.

That's one job sorted. Drilled out the wheel hubs and fitted some M5 nuts, bolts & washers, added a bit of thread lock for good measure and it's ready to screw back on to the fuselage.



Pol.

Pol
Do those plastic? hubs run on a threaded part of the 5 mm bolt? If so the hubs will wear rather fast.

Quorneng wrote: Pol
Do those plastic? hubs run on a threaded part of the 5 mm bolt? If so the hubs will wear rather fast.

Yes they do and I did think about that. I considered using a piece of brass tube as a bearing but then I realized that these are very flimsy foam tyres and they'll wear to shreds long before the wheel hub will. I suppose I could use some epoxy or polyester filler on the threaded part of the bolt that's inside the hub and then smooth it off to make it something like an axle??? If I drill the hub out any more to use a brass tube I think it will weaken it too much. When I first thought about using a tube I thought of just using M4 bolts so I wouldn't need to drill the hub so much, it was a toss up between beefing up the U/C & axle, or saving the wheel hubs. ..... The U/C won!

Pol.

Pol
That's reasonable but what you really need is a pair of these - "PolAxles"!

Smooth load bearing surfaces and the retaining threads are just under tension with no bending!

Doesn't that have to be a made to measure piece of kit Q? .... I get the idea but not all of it.
To the left of the disc is there an un-threaded section? I don't understand why this part can't all be threaded as I assume this fits into the leg itself?
To the right of the disc the smooth section that fits into the hub would have to be made to fit the width of the wheel would it not?
I understand the idea behind the 4mm thread so that the hub would slide over it onto the axle ..... that's the bit I understand.

Pol.

Pol
Yes it would have to be made specifically to suite the dimensions required for the Ruckus.
The reason the threaded portions not going any further than is absolutely necessary is to avoid the 'stress raiser' that any thread creates when under a bending load.
The small radius between the axle and the flange (its on both sides) is there for the same reason.

Really more an exercise in technical drawing than a serious suggestion although it would not be too difficult to make on a lathe along with with suitable dies to cut the threads.

I suppose its just my reaction to a 'high tech' carbon fibre? undercarriage leg being used with 'all threaded" axle!

That's one tool I'd love is a lathe, although it would probably just sit in the corner and look pretty.
I'm one of these people that just like "Men's toys" I don't think I've used a lathe since I was at school. Next on my list is a MIG welder, I've never used one in my life but I'd love to try.
One day I'll win the lottery and will buy my own engineering workshop.

Pol.

"Next on my list is a MIG welder, I've never used one in my life but I'd love to try."
Get a TIG Pol. Once you learn how to use it you will never look back !