I was recently asked by Wes Eaken to recount the modifications I made to the Magician I have been flying off and on for ten years here locally....in the Midwest! Midwest Magician puns intended.
So, you know how we are! A gaggle of modelers in the basement, a stack of plans out on the bench, post micro dissecting others design work, and giving praise where praise is due, ooooos, woooos, and aahhhhs followed by a story about the time that so and so with this design did such and such, with lots of hand gesturing suggesting the planes attitude in flight and accompanied by verbal roaring engine noises.
Brickhaus, had plans in tow, enroute to Brodaks, and out it came. THE boyhood stunt trainer from the 60s that did double duty, as it was easy to learn to fly with, easy to build, and it would stunt nearly as well as its fully fused and flapped counterparts. It had the simplicity of the barn door wing, one single rib to cut and was easy to duplicate in the stack and sand method. Remember, we had no Twisters, Banshees, Coyotes, Rayettes, and numerous others yet. If memory serves me correctly, the AYSD boys thing happened in 1960. Cant remember exactly, but along the same lines, the Oriental was just a few years younger, a fully flapped fairly high aspect barndoor wing, which brings up the Barnstormer, Chief, Black tiger, Still Stuka and.....the BIG JOB...ad nauseum. I love Charlies Big Job. Its on my list. High aspect, no flaps barn door.
Anywho....!!! Magicians were cheap and potent. I knew it was so, and even my Dad had a hand launch Magician for the ball park when I was a wee pup. Sans floppy gear and fat wheels this little plane will turn and groove despite your burping Fox 35. So I wanted one with modifications that were legal.
In the words of Bob Hunt," If a little is good, to much must be just right!" So, modify a Fox, use an old OS35s, or.......build a really light one and put an OS25 fp. I thought I was onto something here. Not quite. She sports a Brodak 40 with a 10-5 TF Powerpoint counter purchased $3.00 prop, a four oz. metal uniflow tank on pressure. Nothing special but it isnt hauled around with the prescribed 19/35 displacement either. Sure you can fly this bird on your preferred nostalgia engine.....I just dont know of a lighter 40. This is just a little better, less hassle, and hauls the mail well on a 36 oz frame, using a 4" bellcrank, a rounded leading edge, straight stiff surfaces....plus
Lets start with the nose. The motor mounts as laid out on the plans are inadequate. I started out with some 12" lengths of 1/2" sq. maple. From the nose past the bellcrank mount. Later on you will drill your bellcrank post hole directly through them.
The gear shown on the plans are canted forward. Great for grass, but sucks for pavement landings. Usually in this era a less than stellar grass landing will result with less insult to score than any other thing. Most contests today are paved , so setting it up for pavement only,will get you an airplane that will land on the mains without the bounce. So we will mount the same gear shown on the plans directly perpendicular to the Center Line 90 degrees using music wire and the lightest free wheeling wheels you can come up with.....just in front of the LE. Wing mounted gear get a 15 degree cant forward with gear down touching just forward of the CG, usually around the LE for conventional aircraft, and always pertinent to CLPA.
Prior to closing up this profile fuse we have several other changes, none of which is to make it lighter, past wood selection. No, I did not go purchase a straight 3x36x1/2" balsa bat for the basic fuselage. I scoured the town hobby huts for the punk lightest non warped straight grain piece of 4x48 I could find. It was finished with carbon veil and finish cure epoxy, dried, sanded and a second coat of finish cure, sanded and painted with goodness gracious ratlle can Sig white dope,I resisted the temptation to enjoy carving them into warped flexy flaps..., cut the crown off of the piece to relieve the pressure, flipped it over and knicked it again on the other side with straight edge and knife true up the base piece for the fuse.
Aircraft grade plywood doublers of 3/32, without warps or overly bowed with twists, were used. Relieve the bow with some steam or a heat gun prior to layup, using 30 minute epoxy and weights on your perfect building surface. I use a 3/8 piece of Lexan, wax paper, and weights...so I can easily view the layup while gluing. There was just a hint of Epoxy around back in the early 60s.....think about what this does for an engine crutch better than ambroid back in the day. Hand cut a very nice wing slot in a the featherweight piece of 1/2" balsa fuse using the much touted #11 blade, and the perfect blanks from the hard aircraft ply doublers we cut earlier.....RIGHT!
This Wing. Its the thing!!!!! sort of. As laid out by Midwest, you might encounter a sharp LE. Eliminate that little caveat and save yourself some wing area. I built a Tom Morris Lincoln Log wing of sorts for this model using the jig blocks I won at a local meet.. heres the rub....diamond LE wings with full open bays, sharp leading edges and a little weight problem stall like fat pigs on the run in loose @#$%. Everybody knows that....RIGHT! Same airfoil with a rounded LE, a little more area, stiff surfaces with no warps twists and mated surfaces.....screw the flaps.
Now on to wing assymetry! So I was fortunate enough to talk to Jim Silhavy at the Nats in 98 or 99 and he says yes I built several, the ones with mild assymetry flew best, with stationary flaps....and I always used half ribs on my wings.
Good enuf for me, its legal, I simply lengthened the Magician's outboard wing one half panel, reducing the assymetry by 1/2. AND..... leave the fuselage location on the plans alone..... and skip the Midwest illusion of workable flaps without hindering rate of turn at input from the pilot with the usual response to this stab location. Oddly enough the stab forward actually assists in loss of equal feel in rate of turn at the handle. Were the wing and the stab on the same vertical plane relative to the thrust CONSTANT. The constant must be power, the variables are many. The blanketing effect of off set surfaces vs cg and thrust is compensated for with the stupid 4" bellcrank! uhhh lemme say it again. Average palm width. Teds handle on most things, not all.
Stab location is not changed, the thickness of the stab is however. Use 3/16 hard C grain for the stab, and the hardest warp free 1/8" C grain you can find for the elevators. On the elevators, use 1/8 music wire and cover mid this section side to side with 1/32 ply that overlaps the joint top and bottom one full inch past the horn arm using 15 minute epoxy. Versus the plans, your elevator horn opening on the fuselage for the stab/elevator joint will be larger...and the section much stiffer and stronger also. It handles the G load well in maneuver even when using RC horns. Resist the temptation to lighten the wood here.
Well...if I skip the heavy paint, I might not need flaps and since Silhavy showed us it didnt need em nearly 50 years ago..... I jumped ship....for awhile....just to see. One thing is for sure, a bone stiff TE is going to be necessary for the stationary flaps (also stiff) to be mounted to. The LE as designed needs more support and is looking for a place to break under load of kit supplied wood and weak joint. Use straight/ straight/ straight A grain sandwich for the LE as well as 1/2 ribs in the
Frankly the stab arrangement never made sense to me. Read what was written, but truth is, if wing loading is centered around the Center of Lift with less mechanical assistance you eliminate lots of variables, you can exhibit a rate of turn, for a given amount of lift, while positively stable in either attitude.....+or- gravity.... times the new found lighter weight thrust packages.........and the lift mechanism is closer to the center of lift without being squirrelly. 40s that weigh like a Fox, plain bearing 46s lighter than your beloved Tigre46 , 10oz 61s, 9oz 51s, dog mushing 75s piped for pleasing power planning....a fraction of the wing loading eliminated, raw power like never before really..easily regulated.....or just let the torque monster putter....similar to recent four stroke torque dorkin storks. I jumped ship for this too.....just to see. Everybody said well..."You Cant Just Stuff a Big Jim Tigre hemi into a Nobler".....like we were comparing apples to oranges!
We have come many miles in a few years in my opinion where model engine development is concerned....only minor modifications to the basic airframes of classic era ships are necessary for our purposes. Problem is we personally are shrinking now while the forces of nature are increasing, and the planes are to big and heavy for the more extreme forces we fly in. Trouble is....all we had was Fox 35s before we had OS35s before we had Tigre46s / OS40/46/51/61/65/four strokes that worked/71/72/75/81s.......have I missed anything really excepted for the names of these fabulous engine geeks that built them.
As a kid I guess I was afraid they might haul me into space with so much power
i WASNT LOOKING FOR MORE LIFT BUT..... I increased the wing area 1.5x 8 inches to reduce assymetry and stiffened every surface while keeping the weight down, put a bigger engine it, bigger bellcrank relative to the average fist with adjustable LO, a few pardigms and axioms...Voila' ...toy airplane...flys pretty good.
Topic: Midwest Magician Mods (Read 2588 times)