To all you guys kicking around the Mini Laser 3D- this airplane may be an alternative- a bit sturdier- similar size, a bit heavier- more scale like- yes I know it's still stand way off and squint scale...

After a snafu, I finally got my kit of this airplane. On the plus side, I think this airplane may do a nice electric conversion-it's coming up in the building queue but I'm a slow builder.
Wings- the only practical thing to do to lighten the wings further is to hack out the centers of the ribs. I'll probably do some of that once I have the wing framed up- not as neat, but it's easier to build a wing with stronger ribs. The airplane has a nice fat airfoil- easy to take some extra weight out of the ribs- also means that the airplane won't be quick. I think this airplane needs a gearbox- direct drive, small props and fat airfoils are a bad mixture.
Tail feathers- built up- no weight reduction required.
Fuse- a bit overbuilt- some lightening holes, needed- probably thinner sides would help, but I won't bother. Wood selection overall in the kit is pretty good.

I suspect that these guys are either being dead honest with the weights of this airplane (listed as 19-24 oz) or they're pessimistic- I'll bet I can come up with a finished electric version under 20 ounces. I'm going to use an MTM S-300 geared 5:1 (Speed 280BB) and an 8 cell 500 SR Max pack. Need to check if the Pixie 7 can handle 3 S80 servos.

At this point, there are a couple of flaws- my kit came with- or rather didn't come with- i.e. directions.

Other boo boos- the radio installation doesn't make sense as shown on the plans.

The plastic wheel pants are way heavy- and are probably going to be left off. I'd probably do that anyway.

Battery access may be a little tricky, but I think it's doable. Note that the airplane is one piece. If anybody's built one and has some other suggestions- please pass them along.

Sam Brauer
Norwalk, CT

Hobby Hangar is here locally and I'm over there every now and then. There is a mini edge 540 flying locally on an astro 020 brushless with 7 cells (700, forget if AE/AR/etc, not familiar with that size cell), direct drive and a 6X3. A Very good builder built it. It's got the wheel pants on it,.. all dressed up, covered in litespan or airspan, I forget which. He did cut lots of holes for lightening. It's 19 oz. ready to fly with the 020 and 7 cells. I haven't seen it fly, but Rich said it flies very well. Rich has one built with a geared speed 300 in it (5 to 1 gearing) and will be using 8 cells. I think this might be a better combination, hae to wait and see. Motocalc predicts a bit better performance than the 020 direct. hmmm,.. $30 setup versus close to $200 setup,.. same or better performance from the cheaper one. I still have a hard time understanding the 10 to 20 times more expensive stuff when a properly geared/propped cheap ferrite does the job.

On another note, he has an RV-7 (yes, the new 7, not 6) about ready to go. Prototype is ready to cover, plans are done, all the laser cutting is setup. It's a real cute one. About the same size as the mini edge. Fuselage is HUGE for a plane that size, area is a bit more than the edge (RV's have medium to low aspect ratio wings) Should make a great conversion with geared S300/S400/020

[This message has been edited by GWRIGHT (edited 07-11-2001).]

With the explosion....(read boom..!) in mini brushless motors these two entries look to be perfect additions to the field of zoom zoom low maintenance models........just a matter of getting over the initial hump (expenditure) and with the increase competition the prices of the gear will fall. Looks like a bright future for electrics.....you gotta like the two year guarantee of these new brushless motors and the idea of... install it and fly it.......forget that gearbox...just something else to maintain..! Looking forward to seeing both these models......already have the Electric Scout and the kit workmanship is excellent........keep them coming from the "hanger" guys....

Strange to see this thread pop up after so long. Rich has flown the 5 to 1 geared sp300 edge, and the performance is/was (not crashed, but pinion slipped on motor, hasn't re-locktited it yet) much better than the direct drive 020 brushless. I'd think the brushless would be much better than the SP300 setup of course, but the brushless needs a gearbox and a "proper size" prop, which the geared sp300 gives you (8X6), so the sp300, although not as good a powerplant, is a much much better match than the direct 020. He's also flown a conversion of his geebee,..endoplasma @ 4.6, 10 cells, 11X10. Had a couple problems due to trying to use a feather reciever, but it's ready to go again. Went like a bat out of you know where,.. pitch speed in the 70's, thrust almost equal weight of plane. Test flights on converted D7 bipe were not great, gotta get prop and gearing right. I totally screwed up the power setup recommendation (prop and gear). Thrust was plenty,.. about 70%~80% of the planes weight, but pitch speed was way too low so although it had tons of thrust, it was barely flying . gotta try some different propping/gearing, lose some thrust and gain some speed. I'd say look for e-conversions of lots of his stuff, although it will be some time, he has other projects that are priority. He wants me to convert an ARF bronco to see if it works, and what to recommend/etc, but I just don't have time right now. He';ll probably kill me for letting this news out, but the 1st and 2nd proto of a new plane are about ready to fly, looks like the electric one will be first since Chip has it built and covered. Glow will be after. The plane is a Grumman Skyrocket. Chips e-powered one will have two endo's, 4.6 ratio, 11X10's on 10 cells each, and it looks like it's gonna be 7.5 to 8 lbs ready to fly (with almost 800 watts).

A Grumman Skyrocket!

I knew there was a good reason the gods of Excessive Consumption (St. Hecht's, St. Wal ) made me buy a second AXI 2820/10 in HL's sale!

Hope it has retracts ?

yes, spring-air 600 series retracts, but drilled out for 5/32 wire instead of 1/8. the front door for spring-air happens to be about 50 feet from the front door of hobby hangar (across parking lot from each other), so I'm sure the "special" large diameter legged 600's will be available if the kit works out . Chip Bullen is building the first, and an employee of Rich's is building the second. Chips is electric, it's built and covered, has motors and gearboxes in it, radio equipment, and retracts, and it's 4 lbs, 6 oz. He still has to paint it though, so I figure 5 lbs after painting and all the little details are done,.. you know, the stuff you never think about weight for, like pushrods and linkages . 20 cells will be roughly 44 ounces, so figure just under 8 lbs completed. Same power as my OV-10, same size, etc,.. so it should go like a banshee just like the OV10 does.

Gary wrote....

(I'd think the brushless would be much better than the SP300 setup of course, but the brushless needs a gearbox and a "proper size" prop, which the geared sp300 gives you (8X6), )

Gary, I found this thread while searching for news on the latest models from HH. When I saw that it was about a year old, I thought about all that has changed, power wise, in that year. With the recent line of mini mega's would not the 16/15/7 or 16/15/8 running an 8X6 prop result in very good performance for the mini edge, etc?

Originally posted by GWRIGHT
yes, spring-air 600 series retracts, but drilled out for 5/32 wire instead of 1/8. the front door for spring-air happens to be about 50 feet from the front door of hobby hangar (across parking lot from each other), so I'm sure the "special" large diameter legged 600's will be available if the kit works out .

So that's why you moved down there

...under $100...

..

I've built and flown my airplane. I'll stand by what I thought about the kit to begin with-it's a very nice flying airplane. My rtf weight excluding motor/battery is a shade under 10 ounces which I think is pretty good for this size airplane. (I think this kit is a better design than a mini laser 3D, having one in the final throes of construction. It doesn't fall together as easily, but the wood selection is better, and the structure is far superior in design. (Working landing gear is a big plus in my book.) One problem is that if you want to use a 7 cell CP 1300 pack, you have to chop into the wing spar slightly. However, it's large enough so that I've been unable to budge it- and my airplane has flown through some pretty strenuous aerobatics.

Powerplants so far: began with a Promax 4014, 7 cell CP 1300, turning an APC 7 x 5 E prop, probably around 12k rpm. Fast, if anything a little too fast, very good vertical pull. Weight about 23.5 ounces. At this weight, the airplane still slows down like a pussycat- nice thick wing is controllable right up to a stall.

Next up- Mega 22/10/6 swinging an 8.5 x 5 prop at about 10,400 rpm. Same batteries, same weight. Surprisingly, not dramatically different, but definitely better vertical performance. Not quite unlimited, but model will do several vertical rolls. Can roll vertically within 20 ft. of ground on takeoff. Motor uses less watts, duration increased. Top end down slightly, but still fast enough to be a little quick. (Doubt if it's significantly slower than a stock J. Ryan warbird on Speed 400.) Still can't get mine to hold a knife edge though- but I'm a far cry ( a really really far cry) from Gary as a pilot.

In a fit of curiousity brought about by the evil Ken Mizell, I began wondering what would happen with this airplane on the Mega 16/15/7. It's not a dramatic change in terms of motor weight, but it sounds like it can use significantly lighter batteries. I'll plan on using the same prop. Theoretically I lose about 800 rpm but shave 3 ounces. We'll see...

Summation- I think this is an underated airplane. I haven't seen the Wattage stuff like their Extra fly, but I'll lay long odds this one fly's better based on comments here -it's lighter and slows down well for starters. The kit is easy to lighten for electric and is well designed. It is one of the nimblest airplanes I've ever flown and that's relatively heavy at 24 oz.

Sam

....really appreciate your factual update, Thanks!

....sounds like another excellent product from HH......

...now what about ....."The all new RV-7/7A " Is it now available?

This is one versatile airframe. I just flew the Mega 16/15/7 turn version for the first time. Swinging a 9 x 4.5 inch prop at 7700 rpm, 115 watts (12 amps) on an 8 cell 1100 AAU pack. All up weight has dropped to 20.5 ounces.

Compared with the previous powerplants, speed is down dramatically. However, the airplane is now much more scale like in flight. Furthermore, the wicked acceleration in down lines is gone- the airplane doesn't get uncomfortable in an extended power off dive. It's much easier to fly aerobatics closer to F3A style- relatively slow- consistent speeds through maneuvers. Vertical pull is down slightly, but the airplane still tumbles fine.

Overall, it's a much easier, more relaxing airplane to fly. I'll fly it like this for awhile- if I get bored, I'll drop the Mega 22/10/5 in it on 6 CP1300 cells to see if I can keep some of the weight down, and the power up.

Sam

CELLS PROP RPM Amps
7 0X0 11850 0.5
7 6 X 5 10600 5 "
7 7 X 4 9800 6.9 "
7 7 X 7 9000 8.4 "
7 8.5 X 5 8500 9.1 "
8 0X0 13550 0.53 "
8 6 X 5 11400 5.6 "
8 7 X 4 10400 8 "
8 7 X 7 9800 10 "
8 8.5 X 5 9600 11.3 "


Sam these figures are from Mega site for this motor.......

You chose a 9 x 4.5 prop at 7700rpm.........any reason? How do you think the performance would change on that 7x7 at 9800 or that 8.5 x 5 at 9600..?

Thanks for the info......it will be entered into my "database" of good performing models...

Bill

I'm not exactly agreeing with Ken's #s. I tried an 8.5 x 6 glass (white) Aeronaut prop first- I kind of remember looking at 8500-8600 rpm and pulling a total of 100 watts at 11 amps. Therefore, I went up a little in prop size since I was shooting for closer to 120 watts.

I suspect what's going on is a difference in speed controllers- I'm using a CC Phoenix 10, and Ken is probably using the MGM Compro or maybe a Jeti which tend to be more aggressive in timing. The variations could also be due to prop design- apparently the APC slow flyer props drop rpm by several THOUSAND!- we don't know what Ken is using.


In terms of the airframe performance- well neglecting the difference of three ounces- I flew this airplane on a 7 x 5 turning over 12k and an 8.5 x 5 turning 10,400. The airplane is much faster with these props, I'll lay long odds that it's still pretty quick with the 8.5 x 5 turning 9600 if you can find a way to do it. That's actually what I was thinking I would get- instead the performance was definitely a lot slower with the 9 x 4.5. On the other hand, the lighter weight really was enjoyable.

Sam