Ruckus pro balsa

[SteveHyde]

The Ruckus balsa undercarriage collapsed in taxing before first flight due to the major design change from the foamy.  The design canterlevers at the fuselage to rip the balsa fixing apart 

[EarlyBird]

9 hours ago, SteveHyde said:

The design canterlevers at the fuselage to rip the balsa fixing apart 

I don't understand. Have you any photos?

[SteveHyde]

The undercarriage wheels rear of the fixing 

[Geoff S]

A clubmate has the foamie version and his undercarriage is mounted like that.  It looks odd (and backwards) and when I commented on it last week he said he'd tried it the other way round but the ground handling is much better with the undercarriage slanting to the rear.  Hardly surprising, really, because it seems to put the wheels in the right place.

 

I've lost track when he got it because of the 'year-off' we've suffered but he's certainly had it since just after they were introduced.

[Stephen Smith 14]

mine did exactlythe same the ply the undercarriage mount is made from is to thin very poor quility and not fixed to anythingsolid enough

[GrumpyGnome]

Interesting..... the piccy on the Century UK web site clearly shows the u/c raking forwards....

 

 

I know this is the foam version but it's the best image ?

 

My personal opinion is that the majority of kit designers assume we all have hard runways and can land so gently that if the wheels were held on with a single strand of spider-web, it'd be OK!

 

GG

[Denis Watkins]

What a shame that the kit provides a useless undercarriage with this smart looking model.

You have correctly identified that to have the wheels in the right place to rotate for take off and landing looks odd.

I would not fit that U/C, but would use a triangulated wire affair.

A faff and a waste but for longevity of the model, fit something else.

[Jeffrey Cottrell 2]

Hi Guys

GG

This gives a much better picture of the balsa Ruckus u/c. Shown as raked back, but notice the mounting point on the fuz is a lot further forward than on the foam version. My foam one has the legs raked forward, but I notice no issues with ground handling.

Denis

Agreed a wire u/c might be a better bet. Depending on access, wonder whether a torsion bar one, raked back, might be an even better option.

Difficult to say without some idea of the internal structure.

Steve, if you're online

Replied to you on the Max-Thrust current consumption thread. Could you let me know which motor you have fitted?

Jeff

[GrumpyGnome]

good spot!

GG

[SteveHyde]

This a picture of the modification using a carbon copy wot4 undercarriage.  It has worked fine for six landings and is no more skittish on take off than the production design 

[SteveHyde]

On 07/04/2021 at 08:01, Jeffrey Cottrell 2 said:

Hi Guys

GG

This gives a much better picture of the balsa Ruckus u/c. Shown as raked back, but notice the mounting point on the fuz is a lot further forward than on the foam version. My foam one has the legs raked forward, but I notice no issues with ground handling.

Denis

Agreed a wire u/c might be a better bet. Depending on access, wonder whether a torsion bar one, raked back, might be an even better option.

Difficult to say without some idea of the internal structure.

Steve, if you're online

Replied to you on the Max-Thrust current consumption thread. Could you let me know which motor you have fitted?

Jeff

 

[SteveHyde]

I have used the Ripmax Quantum II  61  motor . Recommend 12x10 13x10  14x7 15x6 props .  

The ESC is 80A 

[Jeffrey Cottrell 2]

Hi Steve
Thanks for that info.
Had a look on Ripmax website and at first glance that seems to be a bit of a beast for the Ruckus.
Ripmax quote it as equivalent to a 61 ic motor, which seems a bit much for a model that size.
Been a while since I had dealings with ic motors, so I'm open to be corrected, but Century quote the weight as 2.35 Kg or 5.2 lb, which suggests to me a 40, or possibly a 46.
Also the Kv is very low at 410Kv, which is probably why they suggest such big props. As a comparison, my foamie, at 1.5Kg or 3.3 lb flies well on an 850Kv and 10 x 5 prop.
Anyway, seems you have got the u/c sorted, and the model will now take off, so what do you want to improve?
Cheers
Jeff

[Kim Taylor]

As per Jeff's reply above, I was originally replying to the 'other' thread, but have deleted that reply and copied it below:

 

Looking at the spec of the motor you have there @ 410kV, I'd say that it was more suited to a 6 cell LiPo.

To get enough power to get your pro build ruckus performing, I'd say you need to prop it up to something like 600watts. On a 4 cell (14.8v) LiPo, that would mean a current of approximately 41 amps (can't find my calculator). I'd go for the biggest diameter prop you can reasonably fit (say 14") without ground clearance becoming an issue, then experiment with the pitch to get the amps / watts you need.

 

As Jeff said, that's a big old motor for the Ruckus - maybe the best way forward would be to fit a smaller motor with a higher kV (say a Quantum 40 if you want to stay with Ripmax, or a Thumper 4250/06, both @ 800kV) then prop appropriately.

Hope that helps

Kim

Edited April 13, 2021 by Kim Taylor
forgot how to write english!!

[Jeffrey Cottrell 2]

Hi Kim

Always reluctant to suggest a change of motor even if that might end up being the wisest course.

Assuming the quoted weight of the balsa Ruckus is correct, your suggestion of 600w is about right. Works out to 120W/lb.

Having said that, not sure if Century's quoted weight of 5.2 lb is correct. That's almost 2 lb over the weight for the foamie.

Wonder if anyone else has a balsa Ruckus, and can confirm that figure?

Also, need to know what Steves model is lacking.

Originally it had the u/c collapsing on the take off run. That's now fixed but in an earlier post Steve said that a 12 x 8 prop didn't produce enough thrust for lift off.

That also now seems cured, but where to now?

Just my thoughts

Jeff

[Kim Taylor]

Hi Jeff

The problem is that motor on a 4 cell LiPo is never going to set the world on fire - at best it's turning the prop at circa 6000 rpm. At that, unless you've got a lot of prop, the power consumption is going to be low. In my opinion, lack of power / thrust is Steves basic problem - I wouldn't mind betting it's current setup is only producing about 300 watts (complete guess based on gut feeling / personal experience. Best thing would be to get a wattmeter on it to see what's (sorry) actually happening.

Wrt weight, I would think that about 5.5 lbs would be right - the WOT4 artf always seems to come out around this weight, and the models aren't dissimilar.

Cheapest way forward is the new motor - much cheaper than buying multiple 6s LiPo's.

Collapsing u/c is another matter entirely, and shouldn't be allowed to get through QC, or are the customers the beta testers, as usual?

Kim

[Kim Taylor]

21 minutes ago, Kim Taylor said:

Hi Jeff

 

Wrt weight, I would think that about 5.5 lbs would be right - the WOT4 artf always seems to come out around this weight, and the models aren't dissimilar.

Tried to edit this for clarity, but missed the deadline.

Obviously the Ruckus and the WOT4 aren't visually similar, I meant that in terms of size (and therefore weight) they are comparable.

 

Kim

[SteveHyde]

On 13/04/2021 at 20:05, Kim Taylor said:

As per Jeff's reply above, I was originally replying to the 'other' thread, but have deleted that reply and copied it below:

 

Looking at the spec of the motor you have there @ 410kV, I'd say that it was more suited to a 6 cell LiPo.

To get enough power to get your pro build ruckus performing, I'd say you need to prop it up to something like 600watts. On a 4 cell (14.8v) LiPo, that would mean a current of approximately 41 amps (can't find my calculator). I'd go for the biggest diameter prop you can reasonably fit (say 14") without ground clearance becoming an issue, then experiment with the pitch to get the amps / watts you need.

 

As Jeff said, that's a big old motor for the Ruckus - maybe the best way forward would be to fit a smaller motor with a higher kV (say a Quantum 40 if you want to stay with Ripmax, or a Thumper 4250/06, both @ 800kV) then prop appropriately.

Hope that helps

Kim

I will have a try with a smaller motor now. As im new into using electric motors . I just used what the model shop recommended.  Probably all he had in the shop !  It must be noted that century did recommend a motor set-up or battery installation.  I asked for this to be included.  They have not so far. 

[Kim Taylor]

9 minutes ago, SteveHyde said:

I will have a try with a smaller motor now. As im new into using electric motors . I just used what the model shop recommended.  Probably all he had in the shop !  It must be noted that century did recommend a motor set-up or battery installation.  I asked for this to be included.  They have not so far. 

It is shown in the blurb on their website (they actually recommend the same motor as I suggested above). As to how long that info has been available I have no comment to make. It's a shame that you weren't better advised when you purchased that original motor - I think you may have hit the nail on the head with your thoughts above!!

Kim

[ARC]

Hi Guys , 

 

Anyone running an IC version of these . Wondered how the tank lines up with the carb is using the 46. Potential flooding is well known on these 46's when inverted . 

Anyone considered mounting on the side rather than inverted ??

[ARC]

for anyone interested , you cannot side mount a glow as it fouls up on the under cart. Either upright or inverted is the only options 

[ARC]

flew the ruckus the weekend on my os55ax. Went together well . no issues no drama . Motor mounted upright so a little carving of the cowl needed. Undercart as per manual no probs at all. 

Cracking little model , balanced spot on with 2000 nihms under the tank. hi-tech 645mgs all round and a yellow slec tank . Easy 10-15 mins and unlimited vertical . Very responsive and great in low/ tight circuits . 

New weekend hack now . 

[GrumpyGnome]

Hi ARC

 

How's the Ruckus holding up? I'm considering buying the version in the Chippie colour scheme

 

TIA

[Steven Hurd]

Could the undercarriage be fitted forward rake to try to mitigate the cantilever effect, or would this stop it taking off and landing correctly? 
 

I would like one of these but not if the u/c rips off on a regular basis 
 

Thanks 

[GrumpyGnome]

Well, I bought the Chippie colour scheme Ruckus as a 'spare' model, in case I totalled one of my others.  Realised everything I needed to kit it out was laying around doing nothing...... so it's built and flying.

 

Mine is IC powered with a sidewinder engine install - no cowl at mo' - not likely to be much left on one side anyway.  I use a four stroke (TT54) so no problems with exhaust/undercarriage clashing.  Wouldn't have worked inverted or upright as tank:carb position would be pants.

 

It flies nicely but the under carriage is definitely weak - mine came off on the frozen ground a few days ago in a relatively good landing.  It's bolted to a thick enough piece of ply but that's just keyed to the firewall (again, an OK size), and a flimsy former at the back, which is going to be under compression in any landing.  Nothing keyed to sides of fuselage, and no reinforcement if glued areas by, for example, triangular stock.  At least it caused minimal damage when it ripped out..... 😀