Official FMS 1700mm F4U Corsair V2 Thread

[Butchn]

Was about to pull the trigger on one of these birds but man after reading the info here and on RCG I am wondering if that would be a wise decision. I own several FMS warbirds and have had fairly good experiences with them but I never owned one this size. The one I am considering is a V2 ... not sure what that really means, have the bugs been addressed i.e., prop / sequencer etc? I can get it for a little over 3 bills ... but is it worth it?
Thanks for your input.

[PikeStaff]

Hiya, Mr. C - seems we all run the same paths. All good, the only way to finding others experiences and good info.

Anyway - got the Vario from its’ source; http://www.ramoser.de/home_e/variopr...rioprop_e.html

Be aware they are not a cheap addition - by the time you get done with hub, blades, adapters, shipping, etc., you’re going to be in the $130 range. Which, indisputably, is gigantic money for a prop. Of course, it is rebuildable if you break a blade, and it can be used on just about any plane you have....provided that, size-wise, the hub isn’t too big or too small. And it offers a very large range of pitch adjustment, reaching into pitches you just cannot find in conventional offerings. That can be very helpful, especially with some bigger electric-powered stuff.

As we talked about in other places, the addition of the second thru-bolt in the stock prop has - so far - worked very well. A bit over 30 flights, several teardowns looking for troubles, even a couple prop strikes from landing gear issues have not given rise to any failures. And, hopefully, will not. Will keep flying this modded prop as long as possible. Time will tell.

[Corwin51]

Quickie update. Ran the stock 5060-300kv on 6s Nano-Tech 25/50C 6000mA this morning, with 18.6” 4 blade Vario Prop set at 12” pitch.

81.8 peak amps, 1896 peak watts.

Will test the modified FMS 4 blade with a Leopard 6362-350kv, same battery, on a separate stand....yet to be assembled.

Hi PikeStaff, following you here too! *LOL*

Where did you purchase your Vario Prop from?

[PikeStaff]

Quickie update. Ran the stock 5060-300kv on 6s Nano-Tech 25/50C 6000mA this morning, with 18.6” 4 blade Vario Prop set at 12” pitch.

81.8 peak amps, 1896 peak watts.

Will test the modified FMS 4 blade with a Leopard 6362-350kv, same battery, on a separate stand....yet to be assembled.

[PikeStaff]

I think your eval of the prep necessary to assembling the FMS prop is on the money. If things just aren’t going together as you know they should....stop. And figure out where the issue lies. Proceeding without regard to an obvious fault is asking for trouble.

However. FMS 4 blade propeller failures continue to be reported, from newly purchased F4U’s. 2 operators on RCG recently had theirs come apart, one after only 4 flights. Pictures of the failures were remarkably similar - both show the separation of 1 blade and loss of the rear mounting hub. Both are experienced flyers, and when asked about the assembly were freely open that they saw no evidence of mismatched parts or difficult assembly. One did say the prop was emitting some unusual buzzing in the flight preceding failure; he did a visual check but admits he should have pursued investigation, as the prop exploded on his next takeoff run.

There has been some consensus that the prop blade breaks first, thru the outer mounting hole, and that then causes failure of the rear hub, with bolt. As the blades are through-bolted only at their inner hole location, it may be that the blades are not receiving adequate support from the rear hub only, at the outer mount hole. In the interest of evaluating that potential, I have through-bolted my FMS hub at the outer mount hole, simultaneously filling the recess in the blade outer mount hole (the screw head recess) with some steel washers. This serves to tie the front hub directly to the rear, thru the prop blade, and should stiffen the outer mount hole area considerably. Testing has yet to commence, but will be done on a stand soon. Power input will be monitored to at least be commensurate with the stock 5060-300kv outputs, in the 75a to 80a range on 6 cells (around 1800w). It will be carried farther, upwards of 2400w, should testing support it,

Until then, my as-yet unmaidened F4U will fly with a Vario Prop, to avoid that disastrous potential.

[xviper]

Has anyone tried the 3 blade prop from the Flightline 1600 Corsair?
If so, was it a bolt on fit?
Was there enough power with the stock motor? How did it fly?

I have been watching my corsair gather dust for 2 years waiting for FMS to release a fix, but they never will. I hate to fly a brand new plane knowing the prop could explode at any moment. A lot of money to just have wasted.
Thanks,
Jeff

No, but I've gone the other direction. I put on the FMS 1700mm Corsair 4-blade prop onto my FL Corsair. It is almost a bolt on because the hex hole in the FMS prop holder is too big, thereby requiring that I wrap the hex nut on the shaft of the FL one with tape to make up the space. Therefore, if you go with the FL 3-bl, the hole will be too small and the prop will not fit over the nut on the shaft of the FMS plane. You would have to either ream out the hex hole on the blade holder or grind off the nut on the shaft to make it smaller and both options will be hard to do because you are dealing a 6-sided shape. And no, the prop shafts do not fit on the other's motor.
As far as performance is concerned, I found that the FL Corsair flies virtually the same with either prop, so I would imagine that the reverse would be true if you used the FL prop on the FMS.

PS. The "exploding" FMS 1700mm Corsair prop was due to several factors, only one of which was in need of FMS to provide a "fix" and they did about 2 to 3 years ago. If you didn't keep up with reading all the posts about it, you would have missed it. The primary reason why they failed was that FMS issued the wrong blades for the blade holder. I ordered 2 sets at the same time and one set was the correct one and the other was the wrong one. The "wrong" one ended up on some but not all Corsairs. They had an irregularity on the stump that did not permit a perfect fit into the holder. The meant that people rammed those things on with brute force to get the 2 halves to close. The right blades allowed a perfect fit of the clam shell by finger force alone, thus allowing for just a snug but not over tightened clam shell. I had such a "wrong" bladed prop and it shook like a bugger. I could tell right away when I tried to put it together and the proof was when I ran it on the plane just to see what would happen as I brought up the revs. I never flew it until I got the right blades.
Additionally, some people, worrying about something coming loose used Loctite on the bolts. Not only was this unnecessary as the bolts went into nylock nuts, but the Loctite leached out and damaged the plastic on the blade holder. Finally, people balanced the blades by weighing them and making sure that they were all the same weight and some even balanced the whole assembly with blades, BUT they never balanced the central assembly as a unit (without blades). An imbalance in the central assembly can vibrate and destroy a propeller just as easily as an unbalanced one piece multi-blade prop. One part was FMS's fault but the rest (IMO) was in the end user's hands.

[J Mitchel]

Has anyone tried the 3 blade prop from the Flightline 1600 Corsair?
If so, was it a bolt on fit?
Was there enough power with the stock motor? How did it fly?

I have been watching my corsair gather dust for 2 years waiting for FMS to release a fix, but they never will. I hate to fly a brand new plane knowing the prop could explode at any moment. A lot of money to just have wasted.
Thanks,
Jeff

[I-fly-rc-aircraft]

Wow, it's been awhile since anything has been posted here.
Can someone measure the distance between the mounting holes in the retracts? Front to back, left to right.
I'd like to know because I want to replace the Robarts in my 60 Corsair.

TIA
Tom

[OV10]

Have a prop question. Looking at the front of the Corsair the prop is way over to the left about a 1/4 inch or more and down another 1/4 inch. Is this right?

Sounds correct ;)

[prestonowtm]

Have a prop question. Looking at the front of the Corsair the prop is way over to the left about a 1/4 inch or more and down another 1/4 inch. Is this right?

[fieldofdreamsflyer]

Nice video Fieldofdreams and real nice flying. I just love the look of the Corsair when it's flying.

Thanks

[fieldofdreamsflyer]

Great maiden! Well done.

Thanks so much

[Aros]

Great maiden! Well done.

[boomer108]

Nice video Fieldofdreams and real nice flying. I just love the look of the Corsair when it's flying.

[fieldofdreamsflyer]

[fieldofdreamsflyer]

I did the maiden on my friends Corsair stock and think it as great power

[saint]

That is the one I wanted for three prop scale upgrade. Thank you sir that is outstanding!

[OV10]

Will the 18x10 3 blade work nicely???

http://www.aircraftinternational.com...9/Default.aspx

The link you provide is not for the prop you referenced.
Assuming this is what you mean............ Biela 18x10x3
If this is it...............are your intentions to use it with the upgraded 360kV motor? If so............what is your meaning of nicely?
The 360kV motor will handle the load induced by this prop.
Here's the eCalc numbers:
Motor @ Maximum
Current: 87.01 A
Voltage: 19.09 V
Revolutions*: 5965 rpm
electric Power: 1660.6 W
mech. Power: 1442.4 W
Efficiency: 86.9%
est. Temperature: 149 F
est. Speed (level): 52 mph

The Flying Weight for the 1700mm Corsair per the manual is 4700g(number used in eCalc) and not the 4300g listed on the MRC product specification page.

Happy modding ;)

[saint]

Will the 18x10 3 blade work nicely???

http://www.aircraftinternational.com...9/Default.aspx

[Plastic_Aviator]

Never had a problem

Perfect! I just installed the upgrade so Im looking forward to it. Thanks for the heads up!