As per the title, I have a 30cc homelite weed wacker engine. I know it weighs
a few pounds but
if I remove all the unwanted fluff from it, I might be able to shed a few
pounds...or so I hope.
HAs anyone made such a beast fly? My guess is that I'd need a big wing span to
get it up. Right now, I'm debating to either make a 1/5 scale RC dune buggy or
try to turn it into a plane.
I am open to suggestions. Depending on the major concensus, it will dictate
what I'll do with my engine. Thanks for sharing your thoughts.
Dany
I read up a little on using an Homelite weed eater engine for a model boat a
few years ago. From my understanding the engines are designed so that they
don't over-rev i.e. detuned. For converting the engine for boat use, there
was a water cooling (head or jacket, I don't remember) and they had a back
plate that boosted the engine power. I'm guessing for aircraft performance
you'd want to find one of the backplates for higher power. The performance
back plates went deeper into the engine to decrease the volume of the
crankcase and increase pressure of the fuel/oil mixture going from the
crankcase to the cylinder.
RogerN
On 24 May 2009 14:51:56 GMT, snipped-for-privacy@the.candy.store.com (Dany) wrote in
:
Lots of people, I think.
I see to remember conversion kits for weed whacker engines
being on the market. There was a big Cub a long time ago
that set an unofficial endurance record with a chainsaw
engine. They left the pull start on it and used it to
get it going.
You won't get 3D capability from it.
Think "floater." Like a scaled-up ugly stick or a Cub.
As the OP said, you won't get a lot of power from it.
But with the right prop, you will have an engine that
will probably last about forever.
Marty
Converting weed whacker engines to model airplane engines was the popular
thing to do for giant scale airplanes 10 or 20 years ago. Now there are
quite a few purpose-built engines on the market that do much better, even
when they use components from weed whacker engines.
I would suggest that about the only reasons to do this would be if you're
tight for cash or if you'll find it fun. About the only way you'll do
this and stay money ahead is if you have a well-equipped machine shop in
your garage and a lot of drive; about the only way you'll do it fun ahead
is if you want to spend your time tinkering with the engine, have a lot
of drive, and _want_ a well equipped machine shop in your garage.
At the very least you'll have to machine up a prop hub; you'll very
likely want to modify the flywheel for size and efficiency (without
disabling the magneto), and you'll very likely have to mill out a
mounting adapter from the engine to your firewall.
Then there's all the afore-mentioned performance issues.
Other than that it'll be easy and cheap.
Good points by responders.
It seems like you'd do lots of work on the engine for a plane but many
airframes would work and you'd do less to the engine for a buggy or car but
lots of work on the car itself. Just guessing.
:)
mk
A few years back, there were quite a few plans/articles about using Ryoby
weedwhacker engines. I'd suggest a few searches on Google or another search
engine.
Maybe someone here has done it?
Geezer
"Tim Wescott" wrote
It isn't all that bad. I did it with only a friend turning a prop hub. The
rest was done with a sawzall, dremell tool, drill press and assorted hand
tools.
I "milled" the flywheel by cutting off the bulk, chucking the flywheel into
the drill press, rotating it slowly to let the dremell tool grind of the
fins to a reasonable level. Mount was done with a little bent aluminum and
a few longer screws for the engine.
A bit of a floater is good advice, as it will not have more thrust than
weight.
Well it looks like I'me heading for an airplane build. This is my first time
build, I know the physics of flying and such but there will be more questions
like:
How many channels/servo do I need?
What should I use to make the airplane frame that is light, easy to find and
not too costly?
Are there any good plans out there that would show me a good place to start
from?
What size prop would be required for my 30cc homelite and where is the best
place to get them?
I have no idea where the servos are mounted for the flaps...that's scary.
I thank everyone for their responses. I've been looking long and large and a
plane seems to be the better choice rather than a car. There are too many
parts to build a tranny for a car instead of a propeller and plane body.
I am a retired army electronical mechanical engineer and do wood working as a
hobby. I ready for a new challenge. If my plane doesn't fly, then I'll be the
modern day Howard Hughes...minus the germaphobe!!!! LOL
Dany
"Geezer" wrote:
(t>>> As per the title, I have a 30cc homelite weed wacker engine. I know it >>> weighs
Three or four, depending on whether you want ailerons. If you build
something light then you can get away with "standard" sized servoes; if
you build something zoomy you'll (a) need bigger servoes and (b) crash it
'cause you're a beginner.
Balsa and spruce. Sorry, but there's just no substitute for the kind of
floater that you'll want to build. Check your local craft shop or (much
better) your local hobby shop if you have one.
The Hobby Lobby Senior Telemaster is probably perfect for this, if you
can lower yourself to building from a kit. If not that, then some other
big (> 6 foot wingspan) light plane is the way to go.
You want something big and light, and the Telemaster is both.
Sig has a big Rascal model that would probably be suitable, too.
Try
formatting link
and look in their plans directory.
Stay away from scale planes for your first effort -- you want something
easy to build, fly and repair. Scale models -- even models of trainers
-- don't fall into all three of those categories.
Big (probably between 12 and 14 inches, although someone will surely
disagree and be right). You'll want to get them at your local hobby
shop, or mail-order from someplace like Tower Hobbies.
If you mean "flaps" like "landing flaps" then you don't need them. If
you mean "aileron, rudder and elevator" then it depends. If you get a
kit or an ARF it'll all be spelled out.
If your primary goal is to learn to fly, consider going out and buying an
almost ready to fly (ARF) trainer and learning on it before you start in
with the Homelite engine. You _can_ do it the way you're planning, but
its harder than getting and ARF, and in today's market it is probably
more expensive to buy the parts than it is to buy a whole plane.
That Sig Rascal I mentioned _is_ an ARF, by the way, and would probably
be a good platform for the engine.
You should also consider finding a flying field in your area (ask at your
local hobby shop about where to find them, or look on the AMA web site --
formatting link
. You'll learn a lot hanging out there and
seeing how it's done; getting to see inside a trainer before you go off
and build something will be a big help if you insist on doing it from
scratch. Attach yourself to the folks that offer encouragement and
ignore the folks that offer discouragement (much of the discouragement
will be well meant -- as I said, you're choosing a tough row to hoe).
If you're lucky (and if you ask around) there may be someone at the field
or a club nearby that has an airframe that's right for the engine. If
you're _really_ lucky they'll be tired of it and you'll be able to pick
it up cheap.
Sig Rascal was on my mind too but I think it's ARF, that takes some of the
fun out of it.
If Dany lives near me I'll start training him tomorrow.
:)
mk
Central Texas
It's ARF. I was suggesting it in the theory that if you're spending lots
of energy flogging an engine, you may just want to _buy_ the airframe, at
least for your very first airplane.
"Tim Wescott" wrote
What he said!
Seriously, although some have taught themself to fly (I take from the tone
of your questions that you do not fly RC, yet) the odds are way stacked
against you teaching yourself on a home designed airplane. You need to be
learning on a plane that has proven good manners, and flys without the extra
skill necessary to set up a new, unproven design. Plus, the platform you
learn on should be cheap and easy and cheap to repair. It will need to be,
if you are like most learners. A model big enough to carry a 30cc engine is
not going to be cheap or easy to repair.
If you have a good table saw, you can go down to the local big box lumber
store, and usually pick through some two-by-fours or two-by-sixes and find
some close grain, straight grained pine lumber that will make dandy parts
for a model. Douglas fur also works great, but is a bit more costly. It is
even stronger than Sitca spruce that is used in full sized planes, and not
much heavier. Bass wood is great to work, but not as strong. It is
stronger than balsa, but not as strong as most of the above mentioned pine,
but it is also weaker. You will need to size the different woods correctly
as it compares to balsa. You can use 1/4" fanfold styrofoam insulating
material for skins, and it is somewhat structural, also. A big plane for a
30cc would take a lot of monocoat to cover it, and it is expensive. With
the blue foam stuff, you can leave it blue, or paint it after you put
something on to seal it. There are plenty web sites out there with the
details.
You have a lot of learning to do, but it is fun learning. Hit the search
engines on model airplane building, and such. There are videos out there,
and plans are available at some sites.
Please, don't start with the big homebuilt plane, though. Use a teacher to
take off, let you fly until you are about to crash, and recover from the bad
situation you got into, then let you try again after he tells you what you
did wrong. If you do use the big plane without a teacher, the chances are
that you will not be successful, get frustrated and never stick with it long
enough to stay in the hobby. A .40 size alcohol and nitromethane plane is
your best bet, and going that route will leave you with a controller and
servos to use when you build your big plane. Going electric is possible,
but the chargers and such are a mite expensive if you are not going to be
using them for future big gas planes.
As far as how to design your own, there is an excellent page somewhere on
general "rules of thumb" for ratios of tail area to wing area, lengths and
sizes of some part compared to another part, center of gravity, and so forth
that will make about any design fly that is close in line with the
generalities. Perhaps someone here has that page bookmarked and will tell
you how to find it. There is nothing magic about building your own design.
I've only bought one kit in the last 10 or so years. Designing and building
is half the fun, to me.
Good luck, and let us know how things are going.
True story -- a guy shows up at the field with the big (10 foot ARF I think)
Piper Cub. He had never flown RC -- but no fear -- he was a pilot and
knew how to fly. About 5 guys offered to help and told him he was making a
big mistake. But then, he knew how to fly. He was not in the air for a
minute when he lost it. He dumped the remains in the trash, including the
engine/electronics, even though he was told it could be rebuilt (it was
later rebuilt by one of the guys there at the time). End of the hobby for
him!
Good suggestions all. I suggest getting a copy of Real Flight (or a similar
flight simulator).
Another true story -- I was at the field when a guy shows up with a small
electric. He puts it on the runway and stands behind it for the takeoff. A
dead giveaway forsomeone rerlatively new at the hobby. Flys it around a bit
and gets it back to the runway in one piece -- very very pleased with
himself. Turns out this was his first flight -- ever! His ONLY prior
experience was with Real Flight.
Good Luck,
Lee
Sorry MK, you're at the other end of the continent whereas I'm in the atlantic
area. But thanks anyways for offering to teach me!!!
"MJKolodziej" wrote:
Dnews:BNqdnaUWbpb7v77XnZ2dnUVZ snipped-for-privacy@web-ster.com...:> On Sun, 31 May 2009
21:51:20 +0000, Dany wrote:m> (top posting fixed)t>> "Geezer"
wrote:n>>>"Dany" wrote in
message >>>news:4a195f0c$0$32596$ snipped-for-privacy@unlimited.newshosting.com...h>>>> As
per the title, I have a 30cc homelite weed wacker engine. I know ity>>>>
weighsi>>>> a few pounds but >>>> if I remove all the unwanted fluff from it,
I might be able to shed a/>>>> few pounds...or so I hope.>>>>> >>>> HAs anyone
made such a beast fly? My guess is that I'd need a big wing >>>> span tos>>>>
get it up. Right now, I'm debating to either make a 1/5 scale RC duneg>>>>
buggy ors>>>> try to turn it into a plane.a>>>>a>>>> I am open to suggestions.
Depending on the major concensus, it willr>>>> dictated>>>> what I'll do with
my engine. Thanks for sharing your thoughts.M>>>> >>>> Danye>>>>a>>>>n>>>A few
years back, there were quite a few plans/articles about usingi>>>Ryoby
weedwhacker engines. I'd suggest a few searches on Google oru>>>another search
engine.
I'me heading for an airplane build. This is my first >> time build, I know the
physics of flying and such but there will be moreo>> questions like:z>>m>> How
many channels/servo do I need?(>)> Three or four, depending on whether you
want ailerons. If you builda> something light then you can get away with
"standard" sized servoes; ifd> you build something zoomy you'll (a) need
bigger servoes and (b) crash ita> 'cause you're a beginner.e>k>> What should I
use to make the airplane frame that is light, easy to findo>> and not too
costly?o>d> Balsa and spruce. Sorry, but there's just no substitute for the
kind ofb> floater that you'll want to build. Check your local craft shop or
(muchy> better) your local hobby shop if you have one.e> >> Are there any good
plans out there that would show me a good place toa>> start from?i> > The
Hobby Lobby Senior Telemaster is probably perfect for this, if youw> can lower
yourself to building from a kit. If not that, then some otherk> big (> 6 foot
wingspan) light plane is the way to go.s>f> You want something big and light,
and the Telemaster is both.a>d> Sig has a big Rascal model that would probably
be suitable, too.n>o> Try
formatting link
and look in their
plans directory.r> Stay away from scale planes for your first effort -- you
want somethingl> easy to build, fly and repair. Scale models -- even models
of trainers > -- don't fall into all three of those categories.y>
best place to get them?d>f> Big (probably between 12 and 14 inches, although
someone will surelys> disagree and be right). You'll want to get them at your
local hobbyr> shop, or mail-order from someplace like Tower Hobbies.l>b>> I
have no idea where the servos are mounted for the flaps...that'sk>> scary.a>d>
If you mean "flaps" like "landing flaps" then you don't need them. Ife> you
mean "aileron, rudder and elevator" then it depends. If you get ae> kit or an
ARF it'll all be spelled out.r>y>> I thank everyone for their responses. I've
been looking long and larged>> and a plane seems to be the better choice
rather than a car. There are >> too many parts to build a tranny for a car
instead of a propeller ands>> plane body.l>> >> I am a retired army
electronical mechanical engineer and do wood workingr>> as a hobby. I ready
for a new challenge. If my plane doesn't fly, thent>> I'll be the modern day
Howard Hughes...minus the germaphobe!!!! LOL >o> If your primary goal is to
learn to fly, consider going out and buying anb> almost ready to fly (ARF)
trainer and learning on it before you start ind> with the Homelite engine.
You _can_ do it the way you're planning, buti> its harder than getting and
ARF, and in today's market it is probablya> more expensive to buy the parts
than it is to buy a whole plane.w>m> That Sig Rascal I mentioned _is_ an ARF,
by the way, and would probably > be a good platform for the engine.r>i> You
should also consider finding a flying field in your area (ask at your > local
hobby shop about where to find them, or look on the AMA web site -- e>
formatting link
. You'll learn a lot hanging out there ande>
seeing how it's done; getting to see inside a trainer before you go off)> and
build something will be a big help if you insist on doing it fromf> scratch.
Attach yourself to the folks that offer encouragement andn> ignore the folks
that offer discouragement (much of the discouragementt> will be well meant --
as I said, you're choosing a tough row to hoe).
Well Jim, I used to fly using a corded plan when I was about 7 years old. I
also bought el-cheapo electric planes to fly around so I guess it doesn't
really count as far as RC world goes. Like I posted to someone else, I want to
prove myself I can build something that can fly. I bought the G-4 RC simulator
and let me tell you, it is funny as hell to see how many planes I've crash
landed!!!! I have a home theater with 144 inch screen so it is pretty
realistic. My wife keeps telling me she wouldn't get on a plane or helicopter
with me, at least not at the moment. She is also willing to help me build the
plane.
There is no doubt in my mind that I might crash the plane. How many times have
we crashed when we first started to walk? We learnt the hard way and I'm sure
it'll be the same for RC plane.
The only thing I need to see now is an actuall plan for a plane. I've searched
the web sites but none are telling me anything good. If someone out there has
a few websites with any info that would be more than usefull, I'd be very
happy to follow them.
Thanks again for your info and tips. It looks like this newsgroup has lots of
experience in the wings.....(pun intended)
Dany
"Morgans" wrote:
I know, this flight simulator is a hoot! I think it actually contributed in my
desire to build something that I could try to fly. I'm sure training with the
sim will be better than just showing up in a field, turning the engine on,
trying to lift off the ground only to see nose dive right into the side of my
car... :o
Dany
"Lee B" wrote:
Piper Cub. He had never flown RC -- but no fear -- he was a pilot and cknew
how to fly. About 5 guys offered to help and told him he was making a 'big
mistake. But then, he knew how to fly. He was not in the air for a tminute
when he lost it. He dumped the remains in the trash, including the
aengine/electronics, even though he was told it could be rebuilt (it was
later rebuilt by one of the guys there at the time). End of the hobby for
ihim!r Good suggestions all. I suggest getting a copy of Real Flight (or a
similarhflight simulator).ntAnother true story -- I was at the field when a
guy shows up with a small telectric. He puts it on the runway and stands
behind it for the takeoff. A ldead giveaway forsomeone rerlatively new at the
hobby. Flys it around a bit eand gets it back to the runway in one piece --
very very pleased with rhimself. Turns out this was his first flight -- ever!
His ONLY prior lexperience was with Real Flight. fGood Luck,hLee
Dany, do you have any way of opening a .dfx file or other CAD file? I have
,somewhere, a file of a trainer that can be scaled up to whatever size you
want. I printed it once on 8 1/5"X 11 paper that could be taped
together.(I'll look for that file)
I say build the plane and fly it! Please let someone experienced fly it
first. Just trimming a new plane is a chore, let alone learning for the
first time.
mk
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