rcplaincrazy

Brian
No Missing parts here.
here is my first snagg. The manual says to use soft mounts for any engine that creates a lot of vibration.
I am using the mvvs 1.60 would that need a soft mount? I have never soft mounted an engine and am not sure what that means I assume that would mean a special mount of some sort please help anyone thanks

ULTRA-RC

Dick Hanson,

Sorry you did not receive a response to your email. I don't recall seeing it......however I will respond to your first question here and then send you a private email. I'll start by telling you this, I personally set-up and flew one of our proto-types with a Brison 2.4. I picked this engine for a couple reasons. First, because I am confident there will be a lot of interest to put a gasser in this plane. Second, and I don't mean this in a negative way, I wanted an engine with a little vibration to test the strength of the airframe.....I'll leave it at that. The Brison was a very good combo for this plane. It came in at 10.9 pounds dry. I did not use a pipe, and I did not soft mount the engine. I did, however, drill and pin the firewall, soaked the firewall and tri-stock with thin CA as well as the engine box to insure the joints were secure. The results were very good. Awesome power and lightly loaded for a gasser. We were swinging a 19 x 8 Mejzlik prop. So in conclusion, yes, I think the Evo 26 set-up as you mentioned in your post will work well. I would recommend using Lithium batteries for both the ignition and the receiver if you can to keep the weight down. I used Ni-cads in the proto-type as I presumed most modelers would. Oh, and you will not have to work hard to "stuff the pipe".......should be a real easy task. Hope this information is helpful.


rcplaincrazy,

Thanks for posting and letting me know. We came across the one today, and I don't expect there to be a problem, but we will continue to check all the planes to make sure the landing gear sleeves are there.

As far as the soft mount.......here are my thoughts (please, anyone else with experience, add your comments):
There will be many thoughts out there about soft mounts....some swear by them.....some don't. Most pattern fliers will always recommend soft mounts, commonly the Hyde Mount. I notice a "true" soft mount will have less vibration on the airframe at RPM levels equal to mid to high speed......BUT.....I believe there to be a lot more vibration on the airframe at idle and RPM ranges slightly higher. So pro's and con's. In 3D flying, we are constantly adjusting the speed of the plane, and most times are not at full throttle. I do believe they add life to the airframe as well as the electronics. Another alternative, instead of a "true" soft mount may be an isolation mount. These are not as soft as a "soft mount" and not as rigid as a hard mount. The key to answering your question, I think, is knowing the performance of your engine selection. If you think you have an engine that is a good choice for the plane, but may shake a little, it will be wise to "soft or isolate" mount the engine. A smooth running engine, like an OS 1.60 (in my opinion) does not require soft mounting (again, my opinion). I will tell you, my current proto-type has an OS 1.60 ......and it is mounted on a Hyde mount, with a Mueller Header, NMP Carbon Pipe, and a Cline Regulator. Why? The set-up came out of my Icepoint Pattern Plane One last thing.......I believe the key to a "smooooooooth" running motor is a perfectly balanced prop.

Sorry for the long winded post. Contact me with any additional questions....I will get back as fast as I can.

Ultra-RC
Brian Hughes
www.ultrarc.com
[email protected]

rcplaincrazy

Hi. any one thinking of using the tuned pipe with the mvvs 1.6 it will not fit inside the airframe because the header comes out too far from the engine to keep the engine on the centerline. it does work out length wise with the channel if only the header was a closer bend. However the bisson inverted pitts will fit very neatly with minimal cutting of the cowl
I,ll take som pics tommorrow if anyone is interested in seeing this

ULTRA-RC

rcplaincrazy,

Keep in mind, you can rotate your engine in order to align the header / pipe with the tuned pipe tunnel. The radius of the header (rise) will be the key. I personally have no experience in bending headers, but I have heard many times of success in doing so if you can not find the correct one. If anyone with experience wants to add some input here, it would be greatly appreciated.

Ultra-RC
Brian Hughes

JoeAirPort

My Feedback: (41)

ULTRA-RC, I am actually looking for the production kit weight, not the proto-type. But thanks for your help.

Joe

f3a05

I have used both the OS 160 and the MVVS glow, with integral OS pumps, tuned pipes/manifolds in F3A planes.
Also with ordinary silencers in a QQ and EF Yak.
A cheap and reliable soft mount can be done by beam mounting the motor to (preferably aluminium) conventional split-T beams and fixing these to the firewall via four rubber isolation bobbins.
The bobbins that I use are 20 mm diameter, 15mm thick, and have M6 male threaded studs at each end.The degree of "softness" can be varied by choice of (Shure?) hardness of the rubber.They can be obtained in soft,medium,and hard.
I use the medium ones.
If anyone needs a really tight side-to-rear manifold(header), the Hatori HA907 is made specifically for the OS 160, but can easily be made to fit the MVVS by re-drilling the mounting holes in the manifold flange.
Sources in Europe : Manifold--ZN Line. Bobbins---euro-bearings.com
Hope this helps.

f3a05

P.S
Don't be tempted to try this form of soft mount on a back plate mount on this size of glow motor---it worked very nicely on 61 sized pattern engines, but there is a strong risk of crankshaft&/or crankcase breakage on 140s/160s.
As usual, don't ask how I know......

rmh

Soft mounts --
When the engine is truly soft mounted, the restraining point becomes the exhaust system .
This can become an on going problem .
On any single cylinder IC engine, the force you are really fighting is NOT vibration.
It is reaction, from the prop being turned.
The vibration is a node occurring at about 3000 rpm on most engines.
If the prop is perfectly balanced, made from a very stiff material, the reaction is damped by the smooth "flywheel".
Said differently -the prop selected can greatly smooth vibration.
I have had a fair amount of experience with various soft mounting systems -my own and others designs.
Basically, if you can design (modify) the airframe and engine mount such that a soft mount is not really needed--do it .
Ideally, any soft mount captures the engine on crank centerline , allowing only a rotation about this point --a front crankcase ring and center pivot type firewall mount does this but is cumbersome. (the Hyde mount is this type-as well as a number of others, including the hydraulic snubber which is re invented/re discovered every few years.
The Achilles Heel is the coupling to a muffled can/pipe.
This either restrains or flexes and typically causes fatigue to the coupling, header or pipe.

ULTRA-RC

Weights of the Production Run Giles Components - (Out of the box this morning.)


Fuselage with Hatch / Canopy = 2 lbs 1.9 ounces

Rudder = 1.9 ounces

Right Stabilizer with Elevator = 3.9 ounces

Left Stabilizer with Elevator = 4.0 ounces

Fiberglass Cowl = 4.5 ounces

Landing Gear Legs with axles = 1.9 ounces

Fiberglass Wheel Pants = 2.8 ounces

Carbon Stabilizer Tube = 0.2 ounces

Carbon Wing Tube = 2.1 ounces

Right Wing Panel = 14.6 ounces

Left Wing Panel = 15.0 ounces


Total = 5.3625 lbs.



I weighed all the hardware in the enclosed packaging (There are a lot of packages) Total weight = 15.9 ounces

I hope this information is helpful. All components were weighed on a digital gram scale. Please contact me with any questions. Time to ship.........

Ultra-RC
Brian Hughes

STG

My Feedback: (26)

Sounds like the real deal. The total weight is almost Identical to my Funtana 90 out of the box. [sm=thumbup.gif]

According you those weights the plane should come out at 10.5 pounds with an OS 1.6FX and pitts if I put it together with my equipment.

Looks like this plane will be light enough to work with a very wide range of power levels.

JoeAirPort

My Feedback: (41)

Thank you very much. that's exactly what I was looking for. That is indeed the weight it needs to be to some out under 11 pounds. Nice job !!!!

spratrbo

My Feedback: (28)

I have flown the prototype many many times that Chris has with the OS 1.60 and I could not imagine a better set-up. However I am going with the Evolution 1.6 gas engine only for the sake of running gas and I will be running a solid nylon mount. The motor itself weighs exactly the same as the OS. You just have to account for the extra weight of the ignition and the ign battery. I will still be under 11lbs and to account for the extra weight I might consider a smaller gas tank. However... what I am really waiting to see on this thread for those building this model is where they put the wing. For those unaware you have about a 2 inch area (if I remember correctly) for the entire wing to slide back and forth for different flying characteristics. It's much like the Hangar 9 mini Funtana except instead of two wing positions the position is infinite. On Chris' prototype it is fairly far forward and flies rather well. But Chris and I are thinking it might fly better (more high alpha) with the wing moved back about 1/2 inch. Anyone getting this plane please please please post where you set the wing and CG and what your results are. It should be interesting!

JP

BoneDoc

My Feedback: (1)

if you move the wing back, then the CG will be forward. For extreme 3D, you would want the wing forward

spratrbo

My Feedback: (28)

yeah but you can also move the wing back and the battery back. Here's the thing... Chris feels that the tail movement is a bit long. As the wing is right now it will do decent harriers but goes right into a hover before you know it, but also the rudder authority could be better with shorter coupling. KE requires a bit of rudder as well and high alpha KE can be tough. Mind you I am comparing this to a EF Yak which does SICK high alpha KE. If you are not ready for it as well it will snap out on you if not careful. I'm just saying it will be interesting to see the reports back from people on how they like the way this flies as well as engine combos. This is definately one of the best planes I have ever flown though.

JP

BoneDoc

My Feedback: (1)

Well, in theory, with shorter tail moments it will transition from harrier to a hover even faster. With respect to KE, I don't think the wing position should matter much because you're not even riding on the wing

Absolut Yak

My Feedback: (4)

Got one coming! Been waiting since I saw this at Joe Nall.

Haven't decided what to use for power yet. I have four choices. I have a spare DA50 with Slimline, an MVVS 2.15 with full pipe, an RCS 1.40 gasser, and an OS 1.08 with Jerry Smith pipe.

I hear from Brian that someone has used the DA50 with firewall mods and it is overkill on power. So, I'll probably find a better airframe match for the DA. The MVVS is a fantastic motor, but really isn't a noteable weight advantage over the DA, and the pipe is nearly 3 feet long. I think I'll leave it on my OMP 80" Edge profile. That plane weighs 12# even and the motor is a great match.

That leaves me with the RCS and OS choices. The RCS isn't doing anything and swings a 16 x 6 APC at about 9,150 rpms. Total flying weight with engine, muffler, ignition and battery is just under 3#, so about as light a gasser combination as can be had. The OS 1.08 swings the same APC 16 x 6 about 9,750 rpms and weighs somewhere around 30 oz with the pipe. Now, I really, really like gassers and the RCS is probably a great motor to go on this plane. But, the OS has slightly better power and definetly weighs less. I'm thinking lighter is better, even with the cleanup. I'm hoping for close to 10# or lighter with the OS.

I'd have to pull the OS off my OMP 65" Yak 54 profile. That plane weighs 7.5# and the OS flat rips that thing vertical out of hover. It is a dead smooth engine with instant response. So, what to do? Really, it boils down to money. I'd buy a new OS 1.60, or a YS for this thing, but I'm really trying to keep the RC demons at bay. I'm hoping to pick up an airframe from the same factory to match my DA50. If you know what I mean.

Doug

STG

My Feedback: (26)

For sure the 1.08 with pp will be a great combo(has to be closer to 33-34oz with pipe?). It should come out real close to 10 pounds if the weights posted thus far are correct. Just don't be surprised to find out that this thing at 10 pounds is not going to rocket out like something at 7.5 pounds as I think you are pulling very close to 16 pounds of measured thrust. You would have very little !QUOT!get out of trouble power!QUOT! with the 1.4 if it only is turning a 16 x6 9,200.

Have you tried a 17x6 on the 108 with PP? I can see why it was not necessary on a 7.5 pound plane, but on a 10 pound plane you may gain another pound of needed thrust if you are on your pipe. I think you are on your pipe at 9,000 and the OS 108 pulls real hard between 9 and 9,500. Can't remember who, but I think someone makes a lighter wood 17 x6 that should spool up just as fast as the 16x6 apc, but load the motor more up high. [&:]

BTW I have a OS 108 that truns a 16 x6 apc @9550(15.3 pounds of measured thrust) on a 10 pound plane right now and performance is OK, but if I had a magic wand I would wave it and put the 1.6FX in it. No question, the 1.6FX is close to the "perfect" combo.

Take a look here for a small film clip of it...

http://home.comcast.net/~stgflying/INDEX.HTML

Iceman30

My Feedback: (14)

Brian's numbers are on the money. Just weighed mine and it's within an oz or 2!!!!!

dbrford

My Feedback: (3)

Lets see some pics, would like to compare to the prototype. Mine will be here Tuesday but I am impatient...

rcplaincrazy

hi here is a pic of the mvvs 1.6 mouted inverted Im not real happy with this look but its the best I could do with this setup i think it would have looked better mounted on its side

rcplaincrazy

I had to hack the cowl a lot more than I originally suspected. I wasn't sure which muffler would fit better and give a nicer look
do you guys think there will be a problem with the cowl blowing apart there really isnt much left in the front I guess I could always get a new cowl and muffler and mount it on its side. would like to see one with this engine mounted on its side first though.

Absolut Yak

My Feedback: (4)

rcplaincrazy, I think you won't mind how it looks once you get the whole plane together. With the motor mounted inverted rather than sideways, you will have less lateral balance problems. That's a plus.

I recently hacked a cowl up pretty good to get a DA50 with Slimline into the 50cc PA Edge 540 I just toasted. Once the plane was done, it looked pretty clean. I just felt bad about all the cutting until I saw the final product.

By the way, I have an MVVS 2.15 on my OMP 80" profile. I started out with a Bisson muffler and found it was a slug for power. On about flight 20, the muffler fell off and suddenly the plane had mobs of power. It was a whole different beast. Now, other than losing the 60.00 muffler, I was glad it happened. I went with the MVVS tuned pipe and have about 80 more flights on the plane and am completely happy with this setup. Having gone through that long story, I would really recommend cutting off the last 1/4" from your exhaust stacks to increase the outflow diameter of the tubes. I think Bisson makes those pretty ends for good looks, but in reality I think they rob power. Try before and after tach readings. I was not able to do that little mod on my Bisson before I lost it, BUT it was next on my list of things to try.

Good luck!

Doug

seanychen

My Feedback: (4)

OS 108 with Slimline Pitts muffler will swing APC 17x6 @ 9400 RPM.

Iceman30

My Feedback: (14)

Will get some pics up later..not much to see yet.oh, don't know how to post pics..can someone explain how to do it...if you will, will post sooner, don't have time to search forums on how do at the moment...

rcplaincrazy

to Post Photos click on the post reply button at the bottom of the page or one of the reply or quote icons on any post
at the bottom right corner of the text box (the window you type the post in you will see click here to upload underlined in blue
click that link then browse to the pic you want then hit upload the pic cannot be more than Max. 3000KB;
gif/txt/jpg/pdf are supported if the pic is too big it will give you an error message
hope this helps took me a while to figure it out as well