RustyTumbles

I am planning on starting my first gasser project in the new year and I need some advice on the engine selection.

The model will be a World models Extra 300 80" span. Not sure what colour sceme yet, probably go with the patty wagstaff for visibility. Anyway a guy at my club was on of these with a Zenoah G38 in it, it flys very well but he says it's under powered. Do you guys think that it would be under powered with that engine?

I have been looking around for a good engine and I've narrowed my choice to three. One being the G38 if enough power!, a 3W 38i, or a ZDZ 40 RV-L.
The 3W and the ZDZ are alot lighter than the G38 so I think the choice would really be down to 2.

As this will be my first gasser I would like a simple to run and tune, and a reliable engine. Are the 3W and ZDZ good engines? Which do you think will suit my purpose better? I don't intend on flying 3d just good strong scale aero's!

Cap232tain

My Feedback: (1)

Have you considered BME? The 44 and 50's will mount on the mounts supplied by the arf manufacturer. The 44 weight is 2.6lbs and the 50 is 3.3lbs approx. Mine run without any problems!

jclittle

My Feedback: (99)

I've had a GP Patty for about 2 years and at least a couple hundred flights. It has a ZDZ40 and it is more than enough power, not quite enough for high power 3D stuff but I don't fly that way anyway. I know several other people that used DA50's, which for the long haul are probably a better choice. I say this because of reliability, power, your next plane and resale if you want to sell it. The only issue w/the ZDZ40 is that it can be a tough motor to get started. Is there a particular reason why you want the WM Patty? I've built about 4 GP Patty's for other people and seen a few WM Extra's at various events. IMHO the GP is much better in how its built, goes together and overall quality of the finish (fiberglass paint and covering). This is just my opinion. Goof luck.

famousdave

My Feedback: (61)

bigsport -

How set are you on this model?? WM makes nice models, but you are definitely in what we call a "tweener".. too small for a decent 40- 50cc gasser and too big for a small gasser (i.e. 3W-24) 14 pounds won't fly well on a G-38 or 24cc engine. Oh it will fly, but more like a brick than a feather.

The best engine for this plane is the Moki 2.1 Hands down. It will outfly any gasser of comparable size and weight, it will have unlimited vertical and performance... but if really want to convert it to gas .....

A G-38 is going to be scale only for a 14 pound plane, it is a great engine, but a heavy pig, bottom line, you will be disappointed if you want to fly anything but scale patterns, and only basic ones at that. You will have no upline and a very fast downline as the weight will be close to the max for that plane.

If you really insist on gas look at the ROTO 35 or MVVS 2.4 or 1.6 the others are going to be heavier and will have a hard time fitting into your cowl without hacking it. Both the roto and mvvs have machined cylinders (not cast) so they occupy less space and cool better. Both these engines put out some nice power and are very small / lightweight.

The BME and Brison 2.4 will tear the wings off that plane, it just was not built for that size gasser.

I am not sure what the budget is, but if you can spend about $1800 the way to go for your first extra is the Wild Hare. Those planes are built like a brick sh*thouse, specifically for gas power (and yes, they are somewhat heavy) but they will take the abuse a newbie can dish out. That $1800 would include good digital servos and all the other "good stuff" us giant scale flyers use..

Going with a 50cc class engine opens up a lot of possibilities later too when you want to update. You can get a ZDZ 50 or 60, 3W-50, BME, Brison, FPE, Fox, and of course, DA all make 50cc class engines. Fly the WH 'till the wings come off, then go get a comp arf or some other higher end plane later after you have polished your skills.

I went with a 'tweener plane' It has a 3W-24i on it.. While I was thrilled to death with my first gasser I quickly tired of it not being able to fly the advanced patterns or freestyle moves because it simply did not have enough power and was too heavy. I should also note that I have over $1400 in that plane.

Look around on the boards here. Nearly every first timer makes the mistake of converting a plane meant for glow into gas. While the planes fly, they don't fly nearly as nice as ones designed and balanced for gas. I wish Wild Hare or any of the other 50cc planes were available when I went to gas... I spent more money to get what I wanted than had I just bought the "right stuff" in the first place.

I believe this is a common mistake for newbies..
Once I flew a plane with the wing loading and engine box setup for gas.. it was like night and day.
I was pissed at myself for not listening to those around me who "told me so"...

Just trying to save you some disappointment..
DP

vatechguy3

My Feedback: (11)

i built a GP Patty for a friend 2 years ago. its a 78inch span and about the same wing area and weight as the WM Patty. he's running a bme 50 in it. i would say go with either a da 50, bme 50 or 3w 50. the extra power is nice to have for vertical uplines. you just have to remember to pull back on the stick when you're level. plenty of prop clearance too.

tony

Cap232tain

My Feedback: (1)

AMEN!

Rcpilot

My Feedback: (78)

I have a World Models Patty Wagstaff with a Zenoah G-62. Engine is equipped with a C&H Synchrospark electronic ignition system.

My plane weighs between 15.75--16.00 pounds with the tank DRY.

I fly it in Denver, CO at 6000' above sea level. Thats pretty darn high, and planes land hot here. Weight and wing loading is a MAJOR concern at high altitude. That being said, my plane flies GREAT It absolutley flies like it's on rails!!! It lands slow- even here at 6000' above sea level and 16 pounds.

I have NOT overpowered the airframe IMO. I know how a heavy and overloaded plane flies- I've had a few. This plane snaps nicely and it DOES NOT over-rotate in snaps and hard aileron rolls. A heavy plane will snap hard and continue to rotate after you let go of the sticks. A heavy plane will continue to roll after you let go of the stick when performing an aileron roll. I can do aileron rolls all the way down the runway and when I let go of the sticks-- it STOPS rolling-right now.

I'm swinging a 22-10 prop at 7000-7200RPM with unleaded fuel and 40:1 Husqvarna chainsaw oil. It will hover at about 3/4 throttle. I've only done it once, but it'll do it. I'm just too scared to do it. I've got less than 20 flights on this plane-- so not comfortable with it yet.

My setup:

JR Digital Coreless 8231 servos on both ailerons and both elevators. 90oz. in at 4.8 V--probably closer to 100oz. in with my 6V battery.
JR Matchbox to mix my elevator servos.
JR Digital Coreless 8411 on my rudder. Probably close to 180oz. in at 6V
Airtronics Coreless 94145 on my throttle. About 60oz.in at 6V
JR Coreless 4721 on my choke. About 150oz.in at 6V

RX is Hitec dual conversion 8ch Supreme 3500 Series
RX Battery is 6V 2700mah Metal Hydride

My rudder servo is mounted in the tail under one of the elevator servos. I have a short H9 Titanium Pro Link to my rudder control horn.

Elevator servos are mounted in the tail with 4" H9 Titanium Pro Links.

I had to cut into the rudder on one side and open it up. I installed a new hardwood block for my rudder control horn. The stock hardwood block it too high and it conflicts with the elevator linkages. My new block is right at the bottom of the rudder. I just cut the white covering where it meets the black pinstripe. I cut the sheeting-CAREFULLY- and opened it up. I sanded a piece of basswood to fit the shape of the rudder and glued it in. The block is about 1.5"X2" square. I glued the sheeting back on and ironed the covering back on. You can't even see it.

The RX and RX Battery are mounted to a 1/8" lite-ply plate. The plate is glued in at the rear of the hatch area, just behind the wing.

Ignition battery is strapped to the engine box on the left side. Ignition module is strapped to the right side.

Plane is balanced perfectly level upside down.

If you want any detailed pictures of my setup- just email me.

It flies like a dream. The G-62 would definetely be too much power at lower altitude, but I'd slap a 50cc engine on that sucker and never look back. It's a perfect size plane for a 50cc engine at sea level. Just don't try and fly it around at full throttle. You gotta use the throttle stick a lot to fly one of these babies. I fly around at 1/4--1/3 throttle and I use small burps of full throttle for verticle maneuvers. Throttle back to IDLE on downlines and add power slowly as you come to the bottom of loops.

When I pull a loop, I enter at about 1/3 throttle and pull back. I add power slowly as I transition into vertical flight and i'm at full power just before it goes inverted. Then chop the power and let it idle across the top of the loop and all the way down the back side of the loop. Add power back to about 1/3 as you pull back to level flight.

Throttle management is key with these planes. It's not meant to fly fast and they will fly so SLOW- that you don't need lots of throttle to maintain level flight.

I can't say enough about how it flies. It flies GREAT!!! It flies light. It flies slow. You really got to WORK to make it stall.. Mine will stall if you slow it down and let it idle. Then you gotta pull back on the elevator slowly and it will bring the nose up about 20 degrees. Then it kinda drops a bit of altitude and then the nose will slowly fall forward. It kinda "mushes" into a stall and it's actually sinking a lot before the nose actually goes over. The right wing does drop SLOWLY---AFTER the nose is mushed down and falling. It happens so slowly- it's almost funny. You just add a few clicks of power and let it gain some airspeed for a second or two-- then go on to 1/4 throttle and pull it out slow.

I wish I had more time and good weather to fly mine. There's always next year.

The wing attatchment bolts are screwy. It's hard to get your hands inside to get the nuts on the bolts, but it can be done. I mounted my tank over the tube-- on the CG, and it took a lot of space. That makes it really hard to attatch my wings. I went behind the wing tube and cut a hole in the root rib of each wing panel. I epoxied a hardwood block inside the wing root and then drilled and tapped it for a 1/4--20" bolt. I epoxied a nylon 1/4--20" stud into the block. I drilled a hole in the side of the fuse and put some hard ply blocks in for strength. The wings slip on the tube and the nylon stud protrudes into the fuse. I then just use a couple of 1/4--20" nuts on my nylon studs and jam them together. It works very well and much easier to asemble the plane. It used to take my about 15 minutes to get my wings on-- now it takes about 5 minutes to plug everything in and put the nuts on. Much easier now.

The landing gear is kinda weak. When you glue the motor box in-- you can use a piece of 1/4" hard ply and glue it between the LG Mount and the motor box. Glue some Triangle stock to the ply and the LG mount for added strength. It makes the LG a LOT stronger but it will still pull out if you hit hard-- rather than ripping out the entire bottom of the plane.

I really like this plane a lot. It needed a few modifications to get it up to snuff- but now it goes together quickly and I feel confident with landing it.

Get the 50cc engine and don't fly it full throttle. Get good servos and balance it at the back of the recommended range. Mine flies "hands-off" inverted and doesn't lose altitude. It might take a tiny bit of elevator input to keep it level while inverted, but it's so little- that I can't really tell. It pretty much flies inverted with no elevator inut.

It does have some coupling min knife edge- but I just add a bit of elevator. It's not very much, and it's easily flyable with your thumbs-- no need to mix it out. Rudder is STRONG, and it will knife edge loop- no problem. Elevators are really powerfull. I set mine up according to the manual for my first flights- and I mostly used low rates for the first flights. Be carefull with the elevators. Ailerons are very effective too. This plane wil roll so fast- you can't count the rotations.

Again- email me if you want pics of my setup or want to discuss the plane and the mods I made.

RustyTumbles

I'm not dead set on the WM patty, but there is not much in the way of 40-50cc gas planes available in Australia. Is there anybody who imports/exports these planes into australia?
I have not seen the GP patty but I have read alot about it here on RCU. I imagined the WM would be very similar to it.

If a G38 will fly this thing scale wouldn't a ZDZ 40 or 3W 38i pull it around with authority? I think both engines are lighter with ignition and are more powerful as well. I don't want to fly 3d just strong scale and some freestyle spins and snaps thrown in for fun!!!!

I am open to other models I just need to be able to get them into australia with costing an arm and a leg!!

Mattyb

Big sport,
there are a few options here in oz. It depends on what your budget is like. I just got myself a Composite ARF 2.3 m Extra which is imported by Ian howard from Desert Aircraft. Beautifull model. Or you could look at Precision Aerobatics website , they have an edge and an extra for a great price and shaun will look after you completely, am dealing with him to get my gear for the 2.3 and he has been brilliant and giving me great discounts. There is also col taylor who has the great planes models, and the world models extra. or modeldesign has a large range of models if you want to do a heap of building. Im sure there is more, but here in oz it is hard to find these things out. If you want more info, just pm me.

Matty

Velox Pilot

Hello,

The Aerotech Velox is a great choice. I have one with a DA50 on it. I love mine.

Later

Ted

SunShyne

My Feedback: (68)

also consider Wildare, they have great ships for 50cc engines


good luck

matt

Swat Cop

My Feedback: (11)

I would NOT put anything smaller than a 50cc on this plane. The 40cc might be ok but a 50 will be a lot more fun. You can still fly scale with a 50cc but you will have the extra power if you need it and as your skills improve mor ethan likely you will want the extra power.

I have a Dave Patrick Edge 540, I had a Moki 2.10 on it for about six months and switched out in favor of a ZDZ 50 and it was the best decision I could have made. I like the ZDZ engines, light, easy to start and lots of power but any of the big name 50cc engines will be fine. I would stay away from Zenah engines unless you can get a sweet deal on one with an electronic ignition. With light modern engines today it doesn't justify getting a Zenoah and converting it.

rfw1953

My Feedback: (2)

Big Sport - I have the WM 82" WS Extra and love the airplane. I put an OS 160 on the nose and for scale aerobatics it's fine, but by no means a 3-D combo. Flies smooth with no bad habits at all. Take offs and landings are very gentle with no snapping tendencies. tracks straight as an arrow. I have a DA-50 on the G.P. 1/3 scale Pitts and love the engine. I thought about putting the DA-50 on the Extra, but it went in the Pitts. I have seen The WM Extra fly with a DA-50 and it's awesome. The airframe can handle a 50cc engine without any concerns IMHO. If I had it to do over again I wish I had purchased another DA-50 for the Extra. The G. P. version is very similar and a nice option as well.

Couple quick observations on the WM Extra. - Best wheel pants and cowling I have seen in an ARF to date. All parts assembled and fit snug without any alignment problems. The canopy cover opens up from the top side providing ample room to work inside the fuse over the wing area. Two piece wing with aluminum joiner makes for easy transporting and quick field assembly. You assemble the mounting box and install it so you can beef up as needed, but I think it's fine as is for a 50 cc engine. Hard wood and braces provided for this. Covering was very nicely finished out and the model was very well constructed out of the box requiring little mod work. The only thing I did was epoxy the horizontal stab for a secure fit. All in all, still one of the best ARF models in this size on the market. Price isn't bad either. I think I paid 345.00 for mine.

rctom

To answer bigsport's question of availability, Wild Hare planes can be drop shipped from the builder in Thailand to almost anywhere in the world. We have done this for several australian flyers. They will travel by MS and postage will be about US$125 or less.

You can use a G62 on a Wild Hare plane with excellent performance, or any of the lighter 50cc class such as DA, BME, 3w, Brison, FPE, ZDZ, etc.


Tom Fawcett
Wild Hare R/C

RustyTumbles

I will have a look at all the plane you guys have said. My budjet would be around $3000 AUD! I still really like the patty extra though I had a chat to one of the giant scale flyers at the field today and he says that the WM extra would fly great on a 3W 38i.... He says great engine with heaps of grunt!!! Keep the ideas and opinions coming though..........

feral63

bigsport if your budget is 3 grand go back and another look at the p/a edge. you won't be dissapointed.i haven't totaled up what i spent on mine but, it would be around that money i think.

RustyTumbles

I think I will go with the WM extra. I like the mean stance of the extra as well!! The PA edge is a great looking plane too but there is just something about the extra. I think I will go with either a 3w 42 or a DA 50 as they are roughly the same price.

Both these engines are rear induction and I was wondering how do you mount the engine to the motor box? Do you use long standoffs? or can you mount it so the carbie is inside the motor box? Some pics of engine mountings would be great!!

Swat Cop

My Feedback: (11)

You usualy need to do a combination of both standoffs and a hole in the firewall. You will have to determine the distance for proper prop hub clearance from the front of the cowl. You can buy standoffs already made and some even come with the 3' of right thrust built in or you can make them your self out of dowels. I have used both methods. Here is a link to some really nice anaodized custom aluminum standoffs with what ever right thrust built in.

http://www.geocities.com/roger_forgues/engstandoff.html

Here are some pics of my ZDZ 50 and ZDZ 80, both are rear mount carbs. I used the custom aluminum mounts from above link on the ZDZ 80 (30% Ohio RC Extra 300) and I made my own standoffs out of dowel material for the ZDZ 50 (Dave Patrick Edge 540).

RustyTumbles

So it's Ok to have the carbie inside the motor box? How do you tune it if the carb is inside the motor box? How does the engine get a fresh supply of air if the carb is confined to the motor box?
do you set the right and down thrust with the standoffs or with the firewall. The manual for the 3w 42 says to mount the engine on a true surface to stop crankcase distortion. Is this true?
Sorry for all the questions.

Swat Cop

My Feedback: (11)

The carb ("Carbie" LOL) will get pleanty of air inside the motor box, one thing you do have to be careful of is that there is no stray balsa ect floating around inside the fuse that can get sucked into the carb.

To adjust the needles you might have to drill a large hole in the top of the motor box or cut away the top portion to access the needles. I usualy beef of the corners and sides and remove the top portion of the box. I then drill a small hole just big enough to fit a narrow screwdriver blade through. I drill the hole in the cowl so that it is between the high and low setting screws so I can access either the high or low setting needle through the same hole.

It doesn't really matter wheather you have your right thrust in the firewall or the standoffs. I think most people cut the 3' angle into the standoff. If you cut the angle into the standoffs the set on the right side will be shorter than the left and all four will have the angle cut into the end so there is no stress on the crank case.

Swat Cop

My Feedback: (11)

Depending on how much distance there is between the firewall and the cowl, will determine the length of the standoff. If you have a long distace between the firewall and the cowl you might not have the carb inside the engine box at all. below is the pics of my RCS 180 gasser mounted on a CMP Katana. The carb is quite a bit forward of the firwall.

RustyTumbles

how do you mark the 3' on the standoffs?

Rcpilot

My Feedback: (78)

BIGSPORT:

I recieved an email from you about the WM Extra.

I can't reply to it. I got a Mailor Demon telling me that the account didn't exist. I've tried several times, but it won't work.

If noone objects, I can post detailed pics of my WM Patty here on RCU.

What say you?

feral63

i didn't need to cut any thing with my edge. right thrust is already in the firewall.
the thrust lines are marked on the engine box.

RustyTumbles

I've got no problems with you posting more pics. Does anyone else? I think the WM extra has the right thrust built into the firewall also. So do I just make the standoffs the same length and bolt the engine up? What do you do if you need more right or down thrust?