mloywhite

My Feedback: (4)

Hey Desertpig, here's my new USL with G26. I built it according to your plans, with the only deviation being that I cut 3 1/2 inches off the front and bolted the engine directly to the firewall. Otherwise, just as you suggested. I balanced out perfectly. I will post a first-flight report after I try it out this weekend, weather permitting. Thanks for all the advice, Mike White.

chuck l

My Feedback: (17)

Mike,

Just a word of caution. I had all sorts of teething problems with the new G26 on my USL. Didn't run well in the air, but did on the ground. Had at least a dozen dead sticks until I got the problem resolved. I had to run a hose from the metal plate covering the metering diaphragm into the fuselage in order to keep the wind from affecting the carb. Easy to do if you run into the same problem. It was a day and night difference. The problem that still isn't resolved with the engine is that it dies on landing if you bring the idle all the way down. If you keep the idle up, the plane doesn't want to come down. I dialed in some spoiler effect into the ailerons to dump some of the lift. Worked great, you had to keep just a little throttle in until just off the ground. No more bouncing landings either.

Hopefully you won't have the engine problems I had, others haven't had them either.

Looking forward to you flight report.

Chuck

mloywhite

My Feedback: (4)

Thanks for the info. I will watch out for it. I have not tried the engine yet, but it is new. I appreciate you taking the time to post this into. Mike.

ChrisAttebery

My Feedback: (15)

Well,

I did a dry fit of my plane last night. I don't think I'll have any problems with it being nose heavy. The C/G is at 5" from the leading edge. That's with both 1450mA NiMH batterys and the tank under the wing. I might have to slide the batterys forward as far as I can, about another inch. I'm going to recover the fuse this week. Hopfully over the weekend I can glue the tail surfaces on.


Chris

famousdave

My Feedback: (61)

Mike - looks great!! Glad it all worked out... Where did you get that muffler?? It looks loud but really light weight!! Is that a bennett??
I think I might need one.. the one I have looks ounces heavier than yours!

I found another thing that will help you! I LOVE mezjlik props but you might want to consider the MenzS or 3W 18x6 wood if you can find one!! They spool up a lot faster on that G26. I changed my APC out and saw an immediate difference! The CF prop is about 1.5 oz heavier than the Menz.

I went back to the operating table this week... I lightened the firewall with some holes, hogged out the gear plate, installed CF main gear from Graphtech, and some feather lite wheels. Installed a 12 oz gas tank and cut 4" off each wing tip to make the wingspan match fuse length... (I had an extra wing laying around..figured why not!) I also put on a menz prop.

Total weight now at 9 pounds 9 oz!! It was at 10 pounds 6 oz before the surgery... we'll see what the maiden holds later this week!!
I am pretty sure that is as light as its going to get!!

PS - don't worry about the carb. I have NEVER had an issue with these engines and the so-called "carb tube" syndrome. That particular engine must have an air leak, bad gasket or simply needs additional tuning. The G26 is one of the easiest engines to start / run there is. I have set up 10 and no one gave me any problems that could not be solved with a screwdriver!


DP

Just ordered the B&B muffler too!!! 2.2 oz vs 5.9 for the one I have now!!

mloywhite

My Feedback: (4)

I got the muffler from www.wackerengines.com . They specialize in all types of conversions of weedeaters, etc. but make great mufflers. Just email them for any engine they don't show on the website. It was $25, and is very light. I didn't weigh it, but it is a bunch lighter than the original. It's loud, but not too much so. It was really well-made, the pipes are threaded, so you can remove them if you need to. They sell them in 2.5" - 4.0 inch pipes, mine are 3"; I flew the plane yesterday for a bit, but it was really windy though, and I was afraid I would plant it. It has great power, absolutely more than I expected. I may try a Menz prop next, but I got this one new, for $25 shipped, and couldn't pass it up. I was so excited about finally getting it in the air, I forgot to check the RPMS. Thanks again for all the advice. I hope the weather will cooperate Saturday and Sunday, so I can give it a little more of a beating.

chuck l

My Feedback: (17)

DP,

I'm a little confused on the weights of the plane that you have been quoting. Can you clarify the correct weight?

Initially when you started this thread, you said the weight was:
*************************************
"10 pounds 2 oz total weight WET.


Mods: I cut 4" off the front of the plane, shortening the nose and therefore the moment of balance. This completely elminated the need to move the servos to the tail.
I used the stock location. The removed wood weight 4 oz"
************************************************** **********


Later you said the weight was:
**********************************************
"Total savings = 11.25 # - 9.15 #

That is a total savings of 2.1 pounds! That is 19% of the total original weight. HUGE.

I measured this with a high accuracy digital strain gauge I am confident the number is dead on.
Both kits in the box weighed the same before starting. Plywood is less subject to variation than balsa. "
************************************************** ************************************

Now you said the weight was:
************************************************** *********************************
"Total weight now at 9 pounds 9 oz!! It was at 10 pounds 6 oz before the surgery"

2oldultimates

Hi guys. Thought i would share my experience with the USL. I originally had an enya 1.20 four stroke on it. It would hold a hover for about eight seconds then slip out. It was a fun platform to practice with, but really needed more power. I recently bought a Skyshark R/C Christen Eagle 2 and Brison 2.4 (39cc). Since this was my first attempt at flying with gas, I mounted the 2.4 to the USL. WOW!!!! It balanced perfectly with no tailweight. I simply mounted a 2700 5 cell in the tail for the rx. I was only using the USL as a test bed to get a feel for flying the new gas engine, but now i want to get another 2.4 to have the awesome combo back. The USL is just standing in the corner begging to be overpowered again.
BTW, my total weight with the 2.4 w/ pitts muffler and the plane was around 12.5 pounds.

trroscoe

My Feedback: (39)

Chris

I finally got my engine mounted. I printed the pictures that you posted and copied your design. Thanks for posting the pictures they were a lot of help. I cut out the top of the fuse and made a hatch like yours. I still need to mount the ignition and radio gear. I should have it done by this weekend. I haven't flown for 3 weeks and really need a fix. I got me a new Menz S 18x8 prop for the 3W. I talked to Bobby at cactus aviation and this was the size that he recommended. How far have you gotten on yours? Did you mount the servo's in the stock location or move them to the tail? What are you using for batteries. I have one 2700 6V Nimh for the reciever and an 1800 4.8V Nimh for the ignition. I am using Hitec HS 475 BB servo's for everything but the throttle. I will use a standard mini for the throttle. What are you using for a kill switch on your plane. The 3W swithch is like 30 bucks at cactus. I may use one from graeat planes like I used on my wildhare. I set that one up to work with a micro servo so you can kill it with your radio.

Rick

famousdave

My Feedback: (61)

Hey chuck... sorry for the confusion.. I actually have two USL's. I should have clarified that.


USL #1 10 pounds 2 oz wet, 9 pounds 2 oz dry (approx 9.15 #) sorry, I mixed wet and dry measurements... my mistake! I also used a large tank on this plane so it weighs more RTF.

USL #2 9 pounds 9 oz WET It is about the same weight as #1 dry. I saved a few oz by shortening the wing on this one.

I used two different configurations to see if I could lose even more weight , but I think I have about everything out of it I can get without major structural mods they both turned out about the same (within a few oz) .

A 9.5 pound plane on 15 pounds thrust is pretty respectable.

With all the posts I have done on these mods and all the notes I have, it was hard to keep it all straight - that's why my numbers are kind of all over the place... I re-weighed them both empty last night and the numbers above are pretty close +/- an oz or so..

I should know how #2 flies today!
DP

ChrisAttebery

My Feedback: (15)

Rick,

Glad my pictures helped you out. I wound up making my hatch cover the entire top of the nose minus about 1/2" all the way around. I have the ign mounted on the right hand side next to the carb. There's about 1/8" clearance between them.

I basically have to recover the fuse, and finish mounting the radio gear. The servos will all be in the stock locations. I mounted the (2) 1450mA NiMH batteries right under the wing. The tank is on top of the batteries.

I used Futaba 3004s in the wing(4), a HT 645 for the elevator, a HT 605 for the rudder, and a 3003 for the throttle. I used a RCATS electronic kill switch ($25). It only weighs about .5 oz and it is very compact. I mounted it on the opposite side of the nose from the ign.

I bought a 3W 18x8, a Bolly wood 18x8, a Menz S 18x10, and a Menz Ultra 18x10. I should be set on props for a little while. :^) You can get the Menz Ultras from Aircraft International for about $13 right now. Kevin at AI told me the 18x10 Ultra should be a great prop for 3D since it lets the motor wind up better than the wide blade props. We'll soon find out. I'm hoping to finish the plane this weekend.

Good luck and keep me posted.



Chris

Pugsley-RCU

My Feedback: (15)

Good thread....but....I have to say I am confused as why you don't like the quad flaps?

I've had my fair share of US's.....

2 US 40's with OS .70's
2 US 60's with Saito 100's
2 US 1.20's with OS 1.60 (awesome) and one with a G-23 (good cheap fun).
1 USL with Mentor 1.40 and pipe.

I had quad flaps on all of them and they were a blast. Used them all the time. Guess I am not sure why someone would build this awesome, fun, different plane with out taking advantage of a cool set up like the quad flaps.

To each his own I guess.

famousdave

My Feedback: (61)

I ditched the quad flaps in order to shave 4 + oz off the weight number.

I have flown with both wing setups, did not see enough of a diff to keep the quad setup under any circumstances.

Depends on what you want out of the plane. I fly mine insanely and want it as light as possible. As it is I can harrier land mine in a 10' area nearly every time which is what I wanted (I fly routinely in random spots in the desert)..

My experience is if you can lighten the plane up it will fly a lot more "fun" than a heavier plane with quads..

When I say "lighten" I mean significantly. The USL with a G26 is normally a little over 11.5 pounds. Mine are around 9.5!
The G26 on a good prop puts out about 14-15 pounds of thrust.. a little more on pipe.

At close to 2:1 power to weight you can imagine I have a lot of fun!!
DP

chuck l

My Feedback: (17)

desertpig,

Thanks, that clears things up for me.

Chuck

Antique

My Feedback: (4)

G23 to G26 conversion..
Cylinder $72.99
Piston $25.99
Piston rings $23.98
Total without a gasket...$122.96
THEN....The G23 crankcase looks identical on the outside but is too small for the G26 cylinder, so you have to cut the spigot off the bottom of the cylinder...The bolt pattern is different, so the holes in the cylinder must be widened...The G23 case doesn't have enough material under the transfer ports to match the ports in the cylinder, so some of the gain will be lost..
All else is the same, if the G23 is one of the newer ones with the spark coil in front of and just under the carb....Forget it if the G23 is older....
Been there, it still is not a G26, close but no cigar....
I measured 17 1/2 lbs pull on a spring scale on the tail wheel of a plane with a G26 running an Abell muffler and 18-6 Mejzlik prop at 9000 rpm in Phoenix, 1000 feet altitude...GREAT on a 9+ lb airplane...
Bruce Hanson has one on a 13 lb USL (he built it stock) with a tuned pipe, same prop,10,000 rpm..It would be a KILLER on DP's airplane [8D]

famousdave

My Feedback: (61)

Sorry if I eluded to everyone that there is a specific G23 - G26 conversion " kit " apparently there really is not a kit. From what I have heard (and take it with a grain of salt RCIGN1 has a whole lot more exp with these engines than I do) there are indeed some G23s cases that are the same but good luck finding one. I would tend to believe the field experience (RCIGN1) that says there are differences. I do know of one upgrade engine or at least he said it was a conversion (he's not known to tell a lie). here in the phoenix area.. he works for one of the LHS's and I am sure got the parts at cost... maybe even from a salvaged engine, who knows.. It has the same power as my G26.. or at least close enough not to notice the diff.

For all I know he did the mods on the cases.

Even if the cases were the same, If it could be done, and the cost was $123.. it would NOT be worth it. You could sell the G23 and buy a new G26 for less.

RCIGN1 - Thanks for the clarification, that will go a long way with those G23 guys who have been asking me where to get the "kits"..

DP

rfk1381

My Feedback: (7)

DP,

I guess I may have started the "G23 Conversion Kit" chat in this thread. I emailed RCIGN1 and answered me backchannel about the iffy-ness of finding and getting the right parts, so agreeing with his assessment, I just bought a G26 to solve the problem.

Second question: I'm having a bit of a problem location a source for Menz S 18x6 props. Seems no one in Dallas Ft Worth area sells them that I can find. Can you (or anyone) refer me to a source for Menz? (I called Desert Aircraft and they are backordered. I did buy a Bolly from www.bolly.com)

My new USL/G26 is taking shape.

Thanks...RK

rfk1381

My Feedback: (7)

DP,

Well, by golly dang, if I had only read a few posts earlier, I would have seen that Aircraft International has Menz props! My bad.

Antique

My Feedback: (4)

There ARE some G23s that run just like the G26...They were G231PUH helicopter engines..EXACTLY the same except for the bore..Same case, even the same casting number on the cylinder, 2075..Who knows why...
G231PUH, bore 32, stroke 28..G26 is 34x28..CR 8.8-1, same as G26..Timing 30 BTDC at 7000, G26 is 28 BTDC..
Max power 1.58 Kw at 13,000..G26 is 1.62 at 12,000...
Max torque 1.34 N.m at 9000..G26 1.48 N.m at 9000..
The source coil is red on the 231, probably accounts for the timing difference...I put one of these cylinders on a G26 case and got the same rpm, 9000....
Engine rpm for the G231 is 9000-10,500 at WOT....
Small Zenoah engines thrive on rpm, unlike most others that have rpm limits around 8000 so as not to destroy the con rod bearing..Bruce turns his water cooled boat engines at around 17,000 rpm, and has some that turn 21,000...
I think I still have the red source coil from the 231 if anyone with a stock G26 wants to try 2 more degrees of timing...[8D]

famousdave

My Feedback: (61)

Ron - Don't sweat the Menz prop... like I said if you can find one.. no one has them right now... I am using BME and MSC props until the Menz supply improves...

DP

David_Moen

Try Triad Aviation (www.triadaviation.com). I just got a couple of Menz 18x8s from him last week...

famousdave

My Feedback: (61)

Everyone has the 18x8's that is too big for the G26. Its the 18x6 that is impossible to find. I just ordered a few of the bolly props from Gerhard, hopefully those work as well as he says.

I find there is no better prop for the G26 than the 18x6 Menz... period. If the bolly is the same then we're in business.
It appears that Menz may have discontinued making them. Even the larger props are 10 months in waiting to get to the US!

Looks like the bolly wood is the best bet going in wood.
DP

4 stroken ron

My Feedback: (29)

Bump to the top for Ralph.
Great thread BTW
Ron

Antique

My Feedback: (4)

Thanks, Ron, looked all over, even did a search, it said no info..finally put DP in the search and found it...
I cut and machined on a crashed crankcase today, saved a few oz but will have to put my ignition in a separate box...the engine is now about 1/2 inch shorter with a round cylinder and no lugs on the front part of the case, the crank is cut off flush with the rear bearing and an aluminum plug takes the place of the rear seal..It will use the G23 PUH cylinder with the same porting as the G26...I ordered a slippery nickel coated piston and will do a few mods which should get me about 500 more rpm, maybe up to 9500...I called PK and ordered a few 18-6 PK Plus props, very close the Menz design...FWIW, he said a pitch gauge on many props will show less pitch than advertised...His WILL be 6 pitch and 18 diameter...Interesting comparison to my 18-6 Mejzlik....
I tried a CM6 NGK spark plug to make the overall height of the engine shorter..It's not a resistor but about 1/2 inch shorter..It's a short reach and the difference in length lowered the compression enough to lose 200 + rpm...I will spot face the top of the cylinder and put the plug down where it belongs, then use a DA shielded cap and wire on the ignition to stop any stray RF....I might use the old G23 style spool hub and a 6mm grade 8 prop bolt to save a little more weight, I'm looking for under 40 oz engine weight ready to fly...The Abell muffler weighs about 4 oz, maybe a Bisson would be lighter ? Noise is no object, we fly off the taxiway at the local airport....OR, I have a Macs quiet pipe, adds 1000 rpm, but will put some of the weight saved back on...Decisions, decisions...

David_Moen

My US Lite has been sitting out in the garage with skis on it for the past 3 weeks. We had our new years day fly-in, but it was quite cold and the snow was deep, light and fluffy, the plane just sunk up to it's belly so I put it back in the truck. Since then its been waay cold (-28C some days!) until now, now its so warm I'm sure the field is a slush bowl....sigh. I just hate looking at the thing every day on the way out to the truck to head for work!