ZAGNUT

My Feedback: (1)

you should see my "french curve special" airfoils!


at 8 feet and only 10 pounds that plane should be a nice slow relaxing floater but you might have trouble with the sharp LE.

dave

ZAGNUT

My Feedback: (1)

use something like a 16x6 as you need all the thrust you can get. don't use a master airscrew though, you dont have any spare power to waste on inefficient props

dave

CrazyHerb-RCU-delete

My Feedback: (2)

Strato....Dude, you gotta get video on the maiden flight of that thing....Great job!!

I'm working a "rail-type" spad along the same lines..using 6 ft furring strips 3/4x1 1/2. Two for the fuse, one for the spar...
In my 'gallery' here on RCU.

How did you work the wing mounting issue? I don't want to use #64 rubber bands on a giant plane...

Close ups of the engine installation too!! If you can get them...

Great Job!! Looks like a Sunday fun flyer to me!!!

CrazyHerb

strato911

Thanks for the support. I've kept it pretty quiet about this plane, 'cause I'm really taking my time with it. I had hoped to have it ready by now, but alas, not yet. I don't know any local SPAD builders (I know we have some), so I'm probably re-inventing the wheel. It doesn't help that I don't have a building area in my new house yet. For the wing wiring, I made a custom plug using a computer DB9 connector to connect all 4 servos at once with no chance of error. Within the connector, I have all the power and all the ground wires connected together too. I haven't quite decided how I'll mount the wing. It's not to heavy, and since I hope to use it for training, I'll probably use elastics.

This project is filled with personal firsts:

• First SPAD
• First "Giant scale"
• First gasoline conversion
• First dual tank setup
• First home-made muffler
• First computer radio - the new Tracker II & Seeker II receiver (so it can be flown on any channel)

I'll see what I can do for video - I don't have the equipment for digital video, just pics.

CrazyHerb-RCU-delete

My Feedback: (2)

So Far looks like your doing great!!

I've build/Flown .40 sized SPADS.
I've built/flown giant scale.
I've never ran dual tanks (other than one for gas and one for smoke).
I tried home made mufflers and gave up...they all rattled apart.
(However, I have an awseome point of contact though for TOP QUALITY mufflers for around $25 plus shipping).
I used to fly Hitec Spectra module Prism 7 with several different Rx's.

And get this.... I've used a DB 15 connector for a 4 servo wing in my old ultrastick 1.20...hehehe...worked great...but was a PAIN to solder...then dipped in silicone sheath.

Don't ask for pics of the DB15 connector...I wiped out the plane on maiden....(reversed ailerons)...I was so upset with myself I almost quit the hobby...it was the second time in 3 months...both maiden flights...other was a TopCap....

Just keep using those ideas that come up in the SPAD forums and spadworld.net under bigguns....there's a lot of good info out there from those who HAVE done it...

And YES.... I WILL GET MY RYOBI TO HOVER.....
someday!!

Also, definitly know how time goes....try a 5 month old baby...phew...biggest time consumer...then second home based business...and active duty military career to balance...along with keeping a fully functional relationship with my lovely wife. Bless her sole for her paitence with my hobbies and my poor time management skills....oh...and getting tagged with being Vice Pres, Secretary, and webmaster for our club...

Just keep us posted....I'll try the same....
I have my first wing half folded and my cutting board engine mount done....now for 3 more hours......just...got ...to get ....arg...the time....hehehe...

Best of luck!
CrazyHerb

strato911

I've never even seen those forums. I've been to www.spadtothebone.com often though.

Way back in 1990, I came across someone (on the Internet) who had designed what is now called SPAD. They were selling the plans on 'the Net', and I refused to pay. The gears have been turning ever since. :bananahea

strato911

I ran my gas engine again today. The first time since rotating the carb 180°, mounting the engine to my fuselage, and installing the new Seeker II from Polk's Hobbies. Ground based range checks actually improved?!?!? Must be because I was at a different location.

I AM IMPRESSED!!

The RPM readings were better than I expected or even hoped for...

25 cc WeedEater® engine (Poulan),
Master Airscrew 15 X 8 prop (for break-in),
no muffler (not uncomfortably loud, but my muffler isn't done yet),
running slightly rich (4-stroking 80% of the time),
ESSO Synthetic oil mixed 40:1

RMP readings fluctuated at 9640 - 11040 !!!!!! :boxing:

(Before anyone asks, yes, my tach is properly calibrated.)

With that kind of power, what prop do you recommend next?

P.S. More good news - my old starter (standard size sullivan) was able to start it repeatedly with ease.

CrazyHerb-RCU-delete

My Feedback: (2)

Nice....
11K is pretty fast for a gasser...
Bump it up to a 16x8....

Look for 7-9K to be your best top rpm....whatever prop gets you in that range.

Are you using standard size PVC for your fuse? I'd Love to see pics on your mounting method.

Great work!

Keep us updated....

CrazyHerb

ZAGNUT

My Feedback: (1)

then maybe your sunlight is out of whack?

seriously, that sounds way too high for an engine that can you start with a standard starter. can you confirm the reading with another tach?
thats much more rpm than a g-23 with same prop so something must be wrong

dave

strato911

Zagnut - I was alone, hence the need for pictures to prove it. I have previously verified this tach is correct by comparing with another tach, and also by aiming it at a light bulb on 60Hz AC power, and get a reading of 3600 (60Hz X 60sec = 3600 "RPM").

CrazyHerb - Using 2" Canadian gutterpipe from Rona/Revy for the fuse. I bought an aluminum strike plate for where you push open a door and cut it into a square. Drilled the holes to match the crankcase of the Poulan and replaced the bolts with slightly longer ones to go through the plate and the plastic crankcase cover. This just barely fits inside the 2" gutterpipe. I then cut out the corners and wrapped the metal around the fuse. I placed plastic doubler inide the fuse al the way around the mount and then placed 6 screws through both. 2 on top, 2 on the bottom, and one each side.

Here's a close-up.

strato911

I don't know what to tell you Dave - I guess Sullivan is serious when they label it "HI-TORK". Maybe it's just beginner's luck. Also, it was a freshly charged battery.

Volfy

My Feedback: (23)

strato911, sorry about the late reply. I kinda just forgot about about this thread. I was going to say that your 25cc Poulan should fly your "Blue Heron" just fine. With that much wing and at 10lbs, even a stiff piece of carbboard will lift off.

Not to doubt your RPM numbers, but that is one stout 25cc weedie conversion!!!! My twin-ring G-23 and single-ring 25.4cc Kioritz don't get anywhere near those numbers - and they are both "Pro-grade" weedies. If you can verify that the numbers are correct, I'm buying one tomorrow!! Try a 16x6 or 16x8 APC, and tach it in bright sunlight. I know my cheapo tach gets flaky when the sun starts to fade toward dusk. The fact that it fluctuates 1400rpm kinda makes me wonder.

Also, AFAIK spark ignition gasser 2-stroke engines do not "4stroke" anywhere near as much as glow engines do. That spark plug fires every up stroke regardless, so combustion happens pretty much every time. Now when the mixture is overly rich, it might "misfire" every so often, but I don't think it can "4-troke" 80% of the time. That would mean that the darn thing misfires 40% of the time.

strato911

I use the phrase "4-stroking" loosely. You know the sound I'm referring to... when an engine is still running rich, but occasionally gets "on step" to full RPM. Kinda' like:
Bap-bap-bap-bap-bap-brrrrruuuuummmmmmm-bap-bap-bap-bap-bap--brrruuuummmmmm

Almost like a Harley Davidson sound... I assume that was the reason for the fluctuating readings.The RPM's weren't changing wildly. For 20-35 seconds it would be 9600-9700 (sounding rich), then for 10-15 seconds it would be 10200-11000 (with a proper lean sound), then back to the rich sound.

The LHS is closed Mondays, so I can't get a new prop till Tuesday. I'll tach it again then, and hopefully I can get another person with a tach to confirm things.

If I knew I could consistantly convert these with those numbers, I would buy out the surplus center's stock and make my living doing conversions... This may just be beginner's luck, but I'm wearing an ear-to-ear grin.

strato911

Well, the ear-to-ear grin is gone. I have good news and I have bad news:

Good news: It flew! Tons of reserve power. Almost hung on the prop with an APC 16X8. Seeker receiver experienced absolutely no interference from the magneto ignition.

Bad news: I "Dorked" the plane on the maiden flight, and have no video to post. Not enough control surface on the elevator to pull out, plouged in at full throttle before I could cut it. The coil mount broke off, and the front 16" of the fuse is scattered around the crash site. Everything else is salvagable.

What have I learned? The fuselage should be 6" - 10" longer, and it needs a bigger elevator.

I'll post more details (and pics) in the Crash forum in the next couple days.

buckeyes1997

My Feedback: (4)

wow, yer on the right track but id poke around the giant spad site to see if you can learn from others before your next version.

http://spads.mattclement.com