RE: Seagull Ultimate
 

BTW, I would love to put a Saito 180 on it but with the economy the way it is, I think the OS 160 is a better financial choice at this time.

RE: Seagull Ultimate
 

What prop are you using?

A lot of the discussion I've seen online involves propping for low-speed thrust (for 3D), e.g 16x4w, 17x4w etc. These props won't haul the bipe around at speed. You could compromise some low-speed thrust for speed by going down in prop diameter and up in pitch - but this really depends on where you are now.

I'm putting together this plane now with a 120 ax. Based on what I have read, I'm going to start with a 17x6 (I'm more interested in thrust). If I was interested in speed, maybe a 15x10.

If you really can't find a satisfactory prop, then given the 120-ax (with the powerbox mounted pitts style) is the same width and weight as the FS-120, and has 50% more power, it seems a no brainer to switch to the 120-ax. I would think the 160 Fx is too big and heavy.

Maybe somebody who has this plane in the air can comment on propping the FS-120

cheers

RE: Seagull Ultimate
 

Thanks for the advice. I was using TopFlite 15x8. I think I am going to use the OS 120AX like you said. Does the 120AX really have 50% more power?

RE: Seagull Ultimate
 

Only going by OS's web site: 120-ax, 3.1 PS; FS-120, 1.9 PS.

http://www.osengines.com/engines/osmg0650.html

http://www.osengines.com/engines/surpass.html

RE: Seagull Ultimate
 

1.60 would be just right. I'd go for a 26cc gasser myself.

RE: Seagull Ultimate
 

The 160FX is only 2 oz heavier then the 120 4stroke so i might look into that. Thanks guys. Anyone with a 160 on this bipe let me know.

RE: Seagull Ultimate
 

Be careful, (i.e. double check me), but I believe the 160 without muffler is 2oz heavier than the 120-ax with the heavy powerbox muffler.

The 120 is lighter again if you use a bisson pitts muffler or similar.

A fairer comparison would be without mufflers, the 160 is 930 grams, and the 120 647 grams - that is 10oz difference before you bolt on a muffler.

For that kind of weight, I'd also be tempted to go 26cc gas.

Also, check out the comparison between the 160 and 120

http://www.rcgroups.com/forums/showthread.php?t=478975

the 160 is a pretty big lump of metal - will it fit?

The 120 'fits', as the photos in the following thread shows.

http://www.rcuniverse.com/forum/m_47..._7/key_/tm.htm

http://www.rcuniverse.com/forum/m_47..._8/key_/tm.htm

cheers

RE: Seagull Ultimate
 

Thank you buddy, I would love the 160 but i will get the 120 and put pitts on it. Thanks for all the advice and i'll let you know how everything works.

RE: Seagull Ultimate
 

I am using an mds 148 and it fits ok. a 160 would rip that thing to shreds.. Remember.. Just an ARF. White Taiwainese Glue and the like.. Beef it up if your gonna try that.

RE: Seagull Ultimate
 

SV 26 that's going into a Goldberg ARF. Some pics of the fit in the cowl.

RE: Seagull Ultimate
 

Your right, the 160 would tear it up. Thanks, Im gonna order the 120 later. Thanks agains guys. BTW, I did fly this plane with an OS 120 4stroke and it does fly sweet, just not fast enough for my liken.:D

RE: Seagull Ultimate
 

what do you guys think about supertiger engines? looking at the G-3250. Anyone Have or no about?

http://www3.towerhobbies.com/cgi-bin...1&I=LXFV82&P=3

RE: Seagull Ultimate
 

Go for the 2300 instead.

RE: Seagull Ultimate
 

I have a 3250 and like it. But it is way to big and HEAVY for the Seagull Ult.

David

RE: Seagull Ultimate
 

Gino
I have an OS 1.60 in my 73" QQ Yak54, its a rocket. When it came to my Ultimate I chose my OS 1.20AX. I think it is all the motor we need in the Ultimate, I have to tell you I have not had a chance to fly it yet (Chicago). The OS 120AX is a powerful motor, I used it in the 73" Yak prior to the OS 1.60 which is a little over 11 pounds. I will post pictures of the installation tomorrow.
Ron

RE: Seagull Ultimate
 

Ron,

Thank you so much for the information. You will be happy to hear that I ordered the OS 120 AX from tower hobby Mon. morning and hopefully it will get here by the end of the week. Thank you everyone for your advice and hopefully I can post some more pics at another time. I will write back and let you all know how she flies with the 120ax.

Thank you again,
Gino

RE: Seagull Ultimate
 

Ron,

one more qustion, What prop were you using in the 120AX?

RE: Seagull Ultimate
 

rtmmh,
I use a 17X6W APC prop with my O.S. 1.20AX and a 18X6W APC with the O.S. 1.60FX.

RE: Seagull Ultimate
 

I have a 17x6 - I didn't think they made a 17x6W? They make a 17x4W and an 18x6W, as far as I know.

cheers

- Kevin

RE: Seagull Ultimate
 

You are correct Kevin, I didnt take time to proof read what I wrote. Thanks for pointing that out, I dont want to miss lead any one.

In other post I have said I was not happy with the 18X6W on the O.S. 1.60 on my QQ 73" Yak 54. The 18X6W is a good prop and a great one to start with after break in. My comment only concerns my style of flying and my Yak. (both are suspect ;) I would like a prop that comes up on RPM quicker but does not exceed 9000 RPM. suggestions???
Ron

RE: Seagull Ultimate
 

Powerbox scores AGAIN! I used a pitts with my mds... ugh chop city on the cowl.

RE: Seagull Ultimate
 

Hey Ron,

I see in one of your pictures, you have a pitts muffler? did you use it? another pic shows the power box muffler. which one did you use?

RE: Seagull Ultimate
 

Also, where did you get that engine mount and who makes it?

Thanks,

Gino

RE: Seagull Ultimate
 

I tested the Pitts when I had the 1.20 on my Yak, more noise a little more power. The Power box fits the Seagull Ulti better so I used it.

The mount is a DuBro. http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXD633

I can tell the difference with this mount especially if you stiffen the engine box a little. A lot of people complain about canopy rattle when in fact it is their fuse shaking under the canopy cause by poor balance of prop and spinner and poor engine mount or weak engine box. The firewall on the Seagull models are soft lite ply, you can pull a blind nut (which I never use to mount motors) through it. I laminate a thin ply face and back to the firewall and use 10X32 bolts with fender washers (hardware store) under the nuts for the mount. This will never get loose and shake (i hate shaking)

The Ulti only needs the servos mounted and it will be ready. I may leave it as is until spring and go on to other projects. A nearly complete Curare is next, then a 70% complete 60 size Aeromaster Biplane and I have plans I purchased 30 years ago for the Ed Keck Spinks Akromaster but if I can find a Giant Aeromaster ARF for sale I will build it.

Hope this helps
Ron

RE: Seagull Ultimate
 

Can anyone give me the correct incidence settings on the original Carl Goldberg Bluehawk ARF? It appears to be Stab zero, lower wing 1 1/2 degrees positive, upper wing 1 degree negative. I would appreciate any information. kc2jk310s Hank