SIMPLEX oldtimer

[radioflier]

Here is my 1941 Simplex old-timer I built a few years ago. Power is a K&B .28 Sportster engine, but is now on the bench being converted to electric power. Weight of the airframe without radio or engine equipment is 26 oz. Span is 60" with a wing area of just under 600 sq inches. Built from Model Builder magazine plans published a few years ago. Original free-flight plan modified for 3-channel r/c by Stu Richmond. This is the 2nd one of these I built - I lost the 1st one in a flyaway on a warm summer day when the engine quit and I couldn't get out of a thermal. I love building with sticks!!!

[Ian Easton]

That's a real beauty Radioflyer.
What electric "stuff" are you planning on using?

My Black Magic is 60" too and flys great with a geared 480 and 8 - 1600ma Nimh's.
I get about 25 minute flights.

Ian

[Blazer]

Radioflier- You've got a really nice bird there. Like you, I built a Simplex from Model Builder plans. Powered it with a K&B .20 Sportster. Whats coincidential is that mine also got away from me in a boomer thermal that I couldn't spin it out of. I heard later that some guy found it, peeled my name tag off and tried to sell it to a hobby shop. After seeing yours, I'm going to have to build another one- Jim

[radioflier]

Blazer - well at least we've both proved this is a good flying airplane! :rolleyes:

I lost mine when I was idling too long and applied power to get out of a thermal. The engine had loaded up and it quit on me just when I needed it the most. I suspect I hadn't fully broken it in yet. Anyway, it only went up from there until I couldn't see it anymore. I immediately started construction on the 2nd one but didn't get it to this stage before the Ohio winter set in. Lost interest in the spring and it's set in the shop for more than 7 years. Decided to get it out, convert it to electric, and fly it this year!

I sent these pictures to Stu Richmond and he admitted he's lost a few planes to thermals in his years of flying!

ron

[Blazer]

Radioflier- Did you ever try that 12" prop that Stu recommended in his article?

[radioflier]

Sure did! You can't see it in the photo but that is a 12x6 master airscrew antique prop. Like the article said, you could fly around all day with the throttle set just a couple of clicks above idle. That's what got me in trouble. I usually few the SIMPLEX using just the transmitter trim tabs - no need to touch the sticks thoughout most of the flight. I could slowly put that plane anywhere I wanted to in the sky without touching the sticks!

ron

[radioflier]

Ian -

I'm going to try a MagMayhem w/3:1 gear, 8 CP-1700s, and a 11x7 prop to start. This is a combo I have in another oldtimer - an enlarged VECO Sioux. I'll do a separate posting about that plane later.

I'll need all the weight I can muster up front to balance that long tail. I made 2 changes to this version - I lengthed the nose in front of the wing by 1 inch to help the balance problem, and I put in some right thrust in the firewall. The first one really favoured turning to the left all the time.

ron

[Gerald]

...and I put in some right thrust in the firewall. The first one really favoured turning to the left all the time.

ronIn the original design I think the left turning was desirable for freeflight during the powered climb phase, and then some other mechanism would take over to transition to right-hand turns for the glide phase. That could have been right rudder trim, or possibly a weighted right wingtip.

[radioflier]

Gerald - well that certainly makes sense. I've never flown freeflight, but I've heard they turn one way during the power on phase and the other way when gliding power off. Given the natural tendancy to turn left of any plane due to engine torque, it makes sense it would be set up this way.

ron

[zl3vml]

Hi - I built my 1st one in '86. Did not record the span but I guess around 36-40". Weight was 20oz all up. 2Chan and BabyBee for 1/2A Texaco.
With a 8x4 prop I got engine runs of around 4:30 minutes and got some pretty near outa site flights of around 12 minutes.

Eventualy had a "fleet" of around 7 Simplex between a few of us.

Trying to figure out how to add a photo to a post........ :confused:

[clipclop]

Heres my and my sons Simplex40", mines powered with a barbini 1cc diesel , my sons has a cox049 texaco 2ch gear . Both fly well , mine will get up almost oos on 3mls fuel best flyte 43mins -had to bring it down an eagle was starting to get too interested in it .
Stewart
Oh mine were from aeromodeler plans

[AllThumbs]

Is there a picture of the Black Magic 60 posted somewhere?

Interested in what it looks like.

[Ian Easton]

Here's my version...

[zl3vml]

Still trying to figure out how to attach a picture - not sure if it will work this time.
I used to get good engine runs taking it nearly oos but never had good glide performance with my simplex - best time after engine cut was only around 12 minutes....
No - still can't get the pictures inserted - get a Javascript popup asking for the URL. When I select
\\f:\downloads\models\photos\sa\simplex.bmp
It does not work......Doh! Getting too old for these newfangled contraptions!

Mark

[zl3vml]

At last - after a re-install I can attach photos..I think....

[zl3vml]

Five Simplex from our flying group (Sept 1992)

[Allan Wright]

Are these plans still available? Looks like a nice simple quickie build.

[zl3vml]

Allan,

I have the 40" plans and can make a copy for you if still interested.....
(I see your post was quite a few months back)

Mark

[zl3vml]

I have dug out my original one (40" - I found the plan as well:-) and have ripped the covering off and redoing in Tissue. Doh! Stuffed up the wingtips a bit by not getting all the wrinkles out - maybe the dope will do it for me.....
Might have to cut the tissue off the tips and redo them.
Anyway, need to rebuild the fuselage still, as it got totalled in a wingfold about 8 years ago.
Will post some more piccies soon as I progress a bit further.
Mark

[clipclop]

Mark,
I to suffered a wingfold with my Simplex40, when I built my sons I used a spruce spar + added a 1/16 X 1/4 spruce spar between the leading edge and main spar . I placed the sub spar level with the lower edge of the ribs . With this mod the model can be safely looped , spiralled out of lift etc without fear of folding the wings.
Stewart

[radioflier]

My Simplex (the one at the beginning of this thread) was built from Model Builder magazine plans. I lost my copy of the plans some time ago so I can't make a copy for you. You're right - it can be a simple and quick build.

These plans are still available from Bill Northrup's Plans Service as advertised in Flying Models magazine. Bill was the founder and owner of Model Builder and he has all of the plans from his magazine.

ron

[zl3vml]

My plans were from Aeromodeler - can't remember what year though....
I thought of incorporating another spar along the bottom as well, sorry now I have not built it in while rebuilding the wings - guess I will have to stay away from loops :-)
Anyway - loops are not quite the done thing in 1/2A Texaco are they?
Mark

[zl3vml]

Carlos - Glad you got the plans. Here is my Simplex so far. I should get it finished in the next day or so. Uh - maybe a bit longer as I like to give the dope plenty drying time.
Just the fuselage to complete Oh, and waiting for my new radio set to turn up, hopefully within the next week...
Mark

[radioflier]

Nice job on the construction. I noticed you stayed with the verticle uprights on the fuse behind the wing - I took the liberty of including some diagonals. Not true to plan, but I like the look and think there some additional strength in there.

ron

[zl3vml]

I must admit I did consider putting in diagonals as the stripwood I used is pretty soft - but in the end decided against it. Once I had all the uprights and cross pieces in it was firm enough.
I did sheet in the sides and bottom with 1/16" though for a bit more strength round the front end.
With the Tissue on it will be fine. Out of dope for now, so will have to pick up a tin tomorrow.
Mark

[radioflier]

I can see yours is built a lot lighter than mine. When I built mine several years ago I built it for .28 glow and wasn't too concerned about weight. I converted it to electric last fall and it still does fine. If I were to do over again with electric in mind from the start I would certainly build it lighter. Still I'm not complaining!

[zl3vml]

Well, here it is at last - all ready for testflying this Sunday weather permitting.
All up weight 498g (17.5 oz) which gives a 9oz/sq ft wingloading.
Wings were repaired (major). Tailplane recovered and complete new fuselage built.
We have a min wingloading of 8oz/sq ft and use the std tank here in NZ for the 1/2A Texaco class.
Mark

[zl3vml]

I knew I should have put that extra spar along the top as well........ :o

Results of a wing fold due to climbing like a rocket, not enough down thrust and having to hold down on a new and unfamiliar radio.... Ah well, we live an learn. Radio is fine and engine (was buried up to the firewall) has had a stripdown and is ok as well - soooo time for another rebuild :mad:
Edit - my biggest gripe is that was my last 8x4 thimbledrone prop!!!

[johnvb]

Bugger!! :eek:

[vintage1]

Mmm. Check you use enough rubber bands as well - sudden leading edge lift is a recipe for that sort of thing.

Given the ul;tra short moment nose, maybe an idea to both reduce wing indidence as well as adding (lots of) downthrust.

You don't need so much pitch stability with an elevator..

Sincere commiserations. :(

[zl3vml]

Hi Vintage1,
Well, after getting it home it did not look too bad and I am on the way to having it all fixed again. Always look for the positives in the bad and I will make a second firewall that is removable (in fact a few) and then I can fix the .049 to one and different cdrom motors to the others and so make them interchangable.
Well, it was my own stupidity, with the 8x4 prop it needs more downthrust.
I have a 3º thrust plate I made before for the original model which had the same problem.
I had some leaks in the engine and removed it a couple of times and must have forgot to fit it as I Found it in the flightbox afterwards! we live and learn. :o
Mark
PS - my Ebernezer is ready for a coat of dope/fuelproofer......Did you draw that fd7 up yourself ? (just wondering if this is going to be a "design test flight" :D

[zl3vml]

Mmm. Check you use enough rubber bands as well - sudden leading edge lift is a recipe for that sort of thing.

Given the ul;tra short moment nose, maybe an idea to both reduce wing indidence as well as adding (lots of) downthrust.

You don't need so much pitch stability with an elevator..

Sincere commiserations. :(

Captains log 12-October 1992 :)
Added 3º downthrust & 1/16 under wing LE - Spot on !

Grrrrr - wot's the use of keeping logs if you don't read the damn things !!!!
Not sure about that increased incidence though......

[zl3vml]

Rebuilt just B4 Christmas and still waiting for some half decent weather to go fly her again....

Reduced the rudder throw and added sufficient downthrust !

Mark

[vintagemxr]

After reading through this thread a week or so back I did a bit of searching and found that www.hobbyclub.com (http://www.hobbyclub.com) sells a Simplex 60" kit. I ordered it and picked it up at the post office this morning. No chance to roll out the plans and stuff yet but it looks like a decent kit from pawing through the wood a little after I got to work. The Simplex looks like it must be a piece of cake to scratch build but in my old age I'm getting lazy so I decided to pop for the kit.

I'll post a pic or two here when I've finished building it.


Doug

[/url][url="http://www.corgifan.com/05regionals"]
(http://www.corgifan.com/models)

[HelicopterBoy]

The Simplex was the first R/C airplane I ever stick built, my dad scratch built a Cadet Senorita at the same time.

I guess it was probably a little over 10 years ago now.

That thing pretty much taught me how to fly R/C as well as how use/buildthing with my hands.

Mine is/was powered with an OS-25 and I built it with an elevator on both sides as well as a steerable tail gear to make it easier to taxi.

I left it at home when I moved out, right now its hanging up in my old room. I will try and get some pictures next time I'm home. WOW I have had a lot of good times laying on my back flying with the motor off. Its kind of sad the damage fuel has done to it leaking through the monokote. I guess its like seeing your favorite pet grow old.

[zl3vml]

A few guys here are flying 60" versions with four strokes in A-Texaco with great success.
Mine is still going strong in 1/2A-Texaco but I am thinking of electrifying it now.
Sort of putting it out to graze as it were.....

On the other hand - I have also been sitting staring at it - wondering if it needs retiring - or I should I give it a new lease of life?

Hmmm, would a second wing make it a "Duplex" ? :D

Mark

[johnvb]

Which four strokes are they using Mark? Do you know how much fuel they are getting in the A-Texaco comp?

John

A few guys here are flying 60" versions with four strokes in A-Texaco with great success.
Mine is still going strong in 1/2A-Texaco but I am thinking of electrifying it now.
Sort of putting it out to graze as it were.....

On the other hand - I have also been sitting staring at it - wondering if it needs retiring - or I should I give it a new lease of life?

Hmmm, would a second wing make it a "Duplex" ? :D

Mark

[zl3vml]

Which four strokes are they using Mark? Do you know how much fuel they are getting in the A-Texaco comp?

John

Hi John, will have to find out for you.
The fuel tank used in our A-Texaco is the std (14cc) Humbrol tin.
The engine size is limited 1.5cc-3.5cc so I am guessing the engines are around .19-.21 size.
A Max is 10 minutes and they are getting pretty near that kinda engine run alone!
Mark

[zl3vml]

John, I forgot about this.
They use mostly the old OS-20 FStrokes.

I Re-engined my Simplex with a PAW-80 and throttle for some fun flying, but it was too much power and sooo messy, so after a few outings I switched to brushless and two LiPo's and wow - what fun!
Only about 10 grams heavier than with the BabyBee and I get about half an hours worth of chucking it around the sky.

Mark

[ZimboCharles]

Hi All

I've really enjoyed browsing through this and other "old time" threads since I found this site (while looking for pictures of the KK Super Slicker)

I have an ED Bee powered KK Ladybird (unflown as yet) and a Mills 1.3 powered KK Bandit - flies nicely and looks great in the air. All planes now 3-channel RC because I'm no longer up to cross-country running. Also difficult here in the UK due to lack of space

[McGiver]

Cool looking models guys, I hadn't read this thread prior.

[Kiwi]

For those who were wondering, the 36" one came out of the May 64 Aeromodeller.

[chrisrosenkrans]

Here is my new plane. Simplex 60 electrified with 9oz sq ft wing loading. Flew yesterday for 28 minutes with lots of touch and goes.

[gossie]

They are a very nice old thing. Have never built one, but looked at the plan plenty.

[barry wilson]

I remember when this model was on the cover of a model builder magazine. Probably as a drawing or painting.
What I remember most was the graphics or color scheme used. Thought it was quite impressive at the time.
Anyone have that issue and possibly post a picture of the cover for old times sake? Someone might want to try to duplicate the scheme is what I am thinking. I would just enjoy seeing it one more time as well.

[aeronca52]

That fly-by on pic #3 is screen saver material. Jim

[adamtc]

no this is better!!!

Majestic Major.......

[chrisrosenkrans]

That's a pretty good pic.