camaro2007

hello all,
I bought a mini ultra stick this weekend to put my .15 os la engine on (its going to share with my built up mini telelmaster). I read many people have converted the stick to glow, i just wanted to know what servos and recievers people were using...anyone have the crow flaps setup? I was thinking of using HS-55 servos or whatever is recomended for the electric version and a full size 7 chanel receiver. Also what size tank and reciever battery are you guys using? I think im going with a dubro 4oz. tank.

Tim Wiltse-RCU

I don't think I would use HS55's on a .15 sized plane. The HS55's are fine for a 1/2a but not something as large as a .15.

LAter,
Tim

camaro2007

i read a few of the guys in the electric forum are using the hs-55 servos, when converting to a glow should i use something beefier? Also i know there is someone out there with a .15 engine on the mini ultra stick, how does it fly and what size gas tank are you using?

mtntopgeo

My Feedback: (12)

I lean towards Tim's advice. I have a MUS with a Cox Conquest on it. I use HS 81 servos on all but the throttle (HS 55 on that). May be overkill, but provides peace-of mind! .... George K.

camaro2007

what size engine is the conquest? and just curious to what size tank you have in there...oh also did you fuel proof anything?

Tim Wiltse-RCU

The Conquest is a .15. Real screamers too!

Later,
Tim

camaro2007

is that the crazyass .80 something hp engine?

flyinrog

My Feedback: (1)

the Conquest is either an .09 or a .15, and I doubt you could get more than a 2 oz tank in that fuse..and that should be fine for an easy 10 plus minutes/tank..like Tim said ,I'd go HS-81 servo's....Rog

rainedave

My Feedback: (1)

I'll put in a third reccomendation for the HS81s. With a .15 (lots of power for that model) you would never notice the weight reduction the HS55s would give. And you have the security of stronger servos. They're a perfect match.

A 4oz tank is just right. A standard rx is fine but you could save maybe .75ozs with something like a Hitec Electron 6.

Absolutely fuel proof it. No option here. I would also go with a 1/4" aircraft ply firewall (not liteply) and epoxy it well with balsa triangle stock where it attaches to the fuselage side. It will last several seasons this way.

I would use a NiMH rx pack. You can get a 370mah 4.8v NiMh pack from Radical RC for $9 that weighs only one ounce! That's pretty amazing.

mtntopgeo

My Feedback: (12)

Conquest is a pretty strong .15.............. Sullivan 4oz flextank, much more than enough! Had to enlarge the opening of the former just in front of the wing. ....................1/8 in birch plywood firewall, extra seam of gorilla glue on all seams of front compartment, also two coats of Helmsman on the firewall, & interior of front compartment, then I glued the front hatch in place, to make more ridgid, probably overkill! ............ George K.

Tim Wiltse-RCU

george,

If i remember right the Cox Conquest .15 part interchange with the Rossi .15..yes?

LAter,
Tim

mtntopgeo

My Feedback: (12)

I have no first-hand experience in making a comparison, but have read that when K&B first made these for COX, that they did copy the ROSSI. I do know that this engine is a very strong performer. (17,000 RPMs with a 8x4 MAS on 10% nitro, & 20% all castor, & slightly less with a Top Flite.)Way beyond my capabilities. Gonna be a long time before I try more prop, or more nitro. ................George K.

camaro2007

how do you think an OS LA .15 will perform with a 4oz tank 6 HS-81 and 1 hs-55, full size reciever, some smaller 4.8v battery, hardwood firewall, and some fuelproofing? think it will still have a nice vertical?

camaro2007

whats helmsman?

rainedave

My Feedback: (1)

camaro2007, you can get the weights of all the components from places that sell them. Add everything up and figure your wing loading. (weight in ounces divided by area in square feet).

You can download this program to get a fair estimate of thrust on different props:

http://freespace.virgin.net/barry.ho.../thrusthp.html

But the best way is to actually experiment by building the plane and flying it. That's the only way you will really find out what works for you and what doesn't. And that's different for every person. If you are looking for the best 3D setup you might search the 3D forum, too.

mtntopgeo

My Feedback: (12)

I don't have any experience with the .15 LA, but I doubt that you're gonna have any kind of performance problem. Main thing is that even though you'll be carrying two more servos than me, (I didn't hook up the flaps separately.) your MUS should be considerbly less weight. The Cox weighs over 8 & !/4 ozs.. To balance this out, I had to put in a large battery pack. The plane weighs in at over 28 & 1/4 ozs!!!!! I would suspect that you're gonna be at least 4 (maybe 5) ozs less. .................George K.

mtntopgeo

My Feedback: (12)

Helmsman is a spar urethane, protects against almost anything. Made by Minwax, available at most hardware stores & home inprovement joints. Kinda pricey. ................George K.

mylamo

My Feedback: (1)

My mini has HS 81's + 720 Nimh Full size rx 4 oz.tank.
Definitely use at least 1/8 ply for firewall,not lite. The
flaps have proven to be pretty much a waste of time
with that flat bottom wing,however you skould remove
most of the dihiedral if you use ailerons. Looks like
this project is moving along.
The Conquest is almost a Rossi clone and makes at
least the power of any bushing .25

foresterxt

My Feedback: (35)

I just maidened my Mini Ultra Stick with an OS .10fp and a MAS 8x3 prop. It weighed in at 26oz ready to fly less fuel. It was adequate, but barely entertaining. Looks like I'm going to have to go to plan B and up it to a .15. Landings are amazingly easy. I'm using the E-flight S75 servos all around, I hope they hold out!

Dave

rainedave

My Feedback: (1)

Dave, before you take out the .10 try some different props like a 7x4 and a 7x3. I don't think that engine is really unloading on that 8x3.

mtntopgeo

My Feedback: (12)

First flights with my Enya .09-IV powered Mini Super Sportster were with a 8x3 & 8x4. Pretty mundane! I changed to a 7x4, & the thing turned into a little hot rod. I know, the MUS is considerably larger, & probably needs a .15, but, only takes a min. to change a prop.. ................ George K.

foresterxt

My Feedback: (35)

Thanks guys, I'm definitely going to try an APC 7x4 when I get the chance next week. I was taching 12100rpm on the 8x3. It almost seems like it's going to fall out of the sky it flys so slow . The little fp .10 just runs so darn well though, I hope the 7x4 works. It's so quit it almost sounds electric.

rainedave

My Feedback: (1)

Yep. You're not in the range where that engine performs best. One inch of diameter makes a whole lot of difference to a .10. It's probably equivalent to something like three inches of diameter difference on a .60 (I'm guessing!).

edited to add that I'd like to see some kind of chart that shows the equivalent prop loads on different size engines. In other words, going from a 5x3 to a 6x3 on an .049 would be similar to going from a 9x6 to a ? on a .40. Strange things interest me.

camaro2007

what do you think would be the best prop for a .15? Think a OS LA .15 has enough to hover the mini ultra stick?

combatpigg

My Feedback: (3)

your best bet for hovering will be with the MAS 8x3 [blue prop] and the plane will need to be 27 ozs or so.