MTK

Tail wheel assy is super simple. I used a 1/4x20 nylon bolt about 1/2" long, drilled a central hole in it for the wire. A hole was drilled and tapped on the bottom of the fuse to accept the bolt, which was locktighted in place.

The tiller is something I've done for a long time too. The 4-40 bolt that secures the stop collar also as steering tiller. I add a short fuel line extension and secure onto the rudder with a cup fashioned from a 1/4" metal tubing. A pair of screws installed into short nyrod inner pieces in the rudder, complete the assy

MTK

IT FLIES, and it flies very well, even at this early stage of trim.

Took a short hop Saturday to see if everything would stay put. Everything did except the engine.The mounting bolts all came loose and I lost 3 of the 4 bolts. Very strange.......Luckily, no damage to the airframe was done. Back in business today......

danamania

Congrats Matt!

JRgraham

My Feedback: (1)

Great news, Matt! Hope to see a little video of it soon. That one must be a unique accomplishment, being how its something along the lines of something not yet done (meaning a 55cc in a 2m pattern plane making weight even!)

Excellent, Congrats!

MTK

Thank you, JR and Dana!!.

FLIGHTREPORT:

I got 4 flights today, all pattern flights. The plane performs the current Masters better than any model I've seen or flown lately. It's a very honest airplane, extremely smooth responding with very good balance of control in all axes.

Snap rolls must be flown all the way through. The model stops exactly when you release control so it took a few snaps to get the timing right.

It's a fine spinning plane. Even I can do these now....

Knife edges, either side, have zero roll couple as we discussed in the design phase early on. Just a hint of pitch couple which may be trimmed with incidence, we'll see...

The everpresent downline conundrum is a baby carriage on this model. The big wing, big fan up front and the low idle of the 55 slows it way down, too much actually.... We felt that we needed tio bump throttle as we exited downlines....

Yaw stability is better than expected. The large 3 blader tends to destabilize the plane in yaw so I was a little concerned; but it was nothing. Turned out to be dead true, both inside pullsand outside pushes. Fellas who have been at this awhile would appreciate the yaw stability the model displays coming out of verticals. But always at reduced power.....

It flies rather light on its wing; not quite as light as my Temptress did, as Dean P pointed out, but lighter than the Vanquish or my Aesthesis. Vanquish is much lighter than Delta, but it has a tinsy winsy wing and around 10% higher wing loading. Temptress weighed around 10 lbs with an 1100 squre inch wing.....I can get the Delta with that loading but will need the lighter OS GT33 in it

Power to burn of course.Its pace is slow and comfortable at half stick (around 33% servo travel, and around 30% throttle) in little wind. How we do in a fair amount of wind will have to wait til next week. Masters schedules are taking about7 1/2 minutes....I'll play with control arm position to get it to delivermuch reducedpower at full throttle. The 500 cc tank provides just enough gas for two whole Mast schedules when flown this way.

Extremely QUIET as I've described before. This combo is proof that medium sized gas engines don't have to make a chain saw racket

Is it going to last?????? Much too early to tell. Gut feeling tells me that the fuse construction materials will not hold up to the pounding of the big block.....we'll see...

Glad I made a mold. Balsa/glass/carbon sandwich should be more durable......

I will add a turn of positive incidence, and change the power output for next time......

speedracerntrixie

My Feedback: (29)

Matt, I took a good part of today and worked on my DLE55 trying to get it to smoothen out some. I got some results fiddling with the timing and working with the needles but IMO the counterbalance on the crank is just not cutting it. I ended up going external balance by drilling one side of my spinner backplate and then placing it opposite of the piston and rod. Made a huge difference at least by what I could see and feel. I did my runups without wings and in the beginning the airplane would slide to the right at full throttle. By the time I was finished it wasn't doing that I could feel less vibration on my calfs. While I had the cowl off I borrowed an idea of yours, I took 1" glass tape and saturated it with hi temp RTV and wrapped it around the flex portion of a K&S header followed by a wrapping of teflon tape. I had issues with leakage there. BTW. I need to get some fuel tank fittings and fuel line from you. Do you have 5/32 hose? I will need enough fittings for 2 tanks and 5' of hose. Please PM me the price and info where to send payment.

MTK

Shawn,

I don't have 5/32" ID fuel line. I use 1/8" ID (true 1/8") and that has worked great. I think it's large enough for a 150 but I haven't tried it.

It sounds like you lightened the spinner on the opposite side of the counterweight of the crank, ie- effectively increasing the crank counterweight. The spinner in mine is not ideal and the balance is in question, since I had to modify an existing 3" spinner to accept the 20x12. Spoke with Bob Obbenberger last week about a 3 1/4" spinner that's lightened and of course better balanced than mine (which was handcut with a Dremmel)

PM sent

Timthetoolman1

My Feedback: (6)

Very good read, I must get away from the Classic Pattern pages more often. Thanks for sharing.

I read you had problems with the Mylar. It's possible the Klasskote is the problem. I've used Mylar without anything on it for my wings in a vacuum (I think this idea came from Phil Barnes video on glider wings, I suggest it to anyone that wants to see this technique) and I've never had a problem. I do get some residual epoxy outside the wing area that is a bit stuborn so if it's a wing I plan on making a lot of I'll use wax only. Klasskote on the other hand eats through most plastic unless it's specially designed for use on these harsh liquids. I've got some pictures of my results under my Dirty Birdy Build in the Classic forum.

There's a couple things that I want to learn for this forum. Sealing the wood and making landing gear.

I've read where some guys are treating their balsa first so it doesn't soak up too much epoxy. I place my glass and epoxy on the mylar and squeegie out the extra epoxy but it may still be soaking up too much.

I'll have to look up some of your other posts for the gear. I've been wanting to make some for my pattern planes. I figured I'd make a mold and lay them up but I like the way you fixed them in the fuselage.

Tim

MTK

Thank you Tim,

I think my material has fallen on deaf ears for the most part, in this regular Pattern forum. Nobody builds anything anymore in regular Pattern. Guys just assemble stuff that someone else created.But of course, in the classic forum, everyone builds and creates.That's where I'll start to post stuff of general interest from now on.

Klass Kote was not the problem so much. Mylar prep was. Besides waxing, it also needed a coating of PVA. Moldsfor the various parts I make which areprimered first, always are PVA'd before the primer step. These have never failed to release the primer perfectly. If I didn't use any primer though, I agree the mylar would have released fine as is. Point is if one needs to bring a molding out of the mold fully primed or painted, best to PVA the mold first to produce a proper barrier between the surfaces.

Sheeting sealing is a good practice to get into. I use hair spray much of the time but also use nitrate dope occasionally (but never use butyrate). Weight gain is a couple grams for 500 square inch sheets. But that savesat least a half ounce of epoxy per sheet (a couple ounces at least, per wing)in the end

Squeegie use is a must. But even 1/2 ounce glass cloth is thicker than silkspan and will hold more epoxy than necessary. Plus there's weave to deal with if you remove too much epoxy. Let me suggest that you use silkspan next time. It will be lighter and of course thinner but more prone to hanger rash. Except the surface would need a minimum of filling so it would require less work...

I've been doing clam shell moldings of gear and props since the early 80's. It takes time to get experienced enough to make things strong and light. The whole gear set shown in the thread is a scant 4.3 ounces, with axles but without wheels. The mount in the fuse is about 1 ounce.Everything is plenty strong for an 11 pound model.....Good luck with your molding efforts and if I can help, email me

serious power

Hi Matt,
Some of us read every post you put here - just so you know.
I for one appreciate your efforts.

Brian

Jetstream

My Feedback: (6)

I agree with you that building is becoming a lost art, but I still love building. I having been building and flying 30 years now and still learn some new techniques from your build threads. Thank you for taking the time and effort for posting your projects. I know it is such a thankless giving most of the time.

David K.

MTK

Thank you.....

Something Shawn wrote triggered me to remove the hand cut spinner and run the engine without. I also reduced throttle throw to about half.....so now, full stick gives me barely 50% opening of the butterfly.....

The engine started immediately and fullstick gives me just about 5500 rpm, or about 1300 rpm off its real full throttle. The most important thing was that the engine was smoother without the hand cut spinner. Never did check balance on it but obviously, it has to be way off. Bob Obbenberger at Tru Turn is cutting me a custom light spinner.....

I need a wood 20x12 electric 3 blader to laminate for gas. The Mezjlik is a terrific prop but is a little heavy.

cmoulder

Matt, those 3-blade gasser props are indeed pretty heavy.

If you want, I think I have a couple of 20x12 PT electric CF props that I would be willing to donate if you want to try making a 3-blader. I noticed (and I'm sure you have seen) that for the woodie 3-bladers they use a phenolic disk in the hub and peg the blades. I don't know if this would work with the carbon e-props but if you want to give it a shot let me know. Probably not compatible with your protocol for sanding down the wood props, but maybe you're in the mood to try something new.

If you're going to Pocono I can bring them with me.

MTK

There's an idea. Thanks Bob, I'l take you up on your offer. Yes I'll be there.

Hopefully there's enough hub area to allow 4 bolt holes....for the life of me I don't get the reason why gas engine makers insist on 4-6 bolts to mount a prop. Not necessary for anything up to 100cc

speedracerntrixie

My Feedback: (29)

Matt, maybe use a couple G-10 disks larger then the current hub and then fill the voids between blades with an epoxy milled fiber and cabosil slurry followed by your lamination process. Hysol 9396 would be a great epoxy for this especially if you did a 150 degree post cure with 5 degree per min ramp rate. Just don't forget breather holes. I know I really didn't have to mention breathers with you, just the composites tech in me. Lol

JAS

My Feedback: (2)

Why not have Bob make you a single bolt hub for the DLE? We have one on my original TOC 3W 70 twin from TT and it works great. Never had a prop slip, even running on carbon pipes.

cmoulder

Matt, I checked the stash of props today and in fact have 2 of the props on hand, so I will bring them to Pocono.

Looks as if there is a viable single-bolt solution, and you have some suggestions from those who know way more than I do. As they are, the unmodified hubs are quite delicate for a gasser application, but I know that you will figure out how to make it work.

MTK

Thanks for the suggestions Shawn. I doubt that there'd be any issue with prop modifications. When I see Bob's I'll know what needs to be done.

The biggest issue is weight savings. The Mezjlik prop weighs 156 grams. A modified e-prop could be built at 100 grams I believe. Having the prop work as well as the Mezjlik does will be the key......

BTW there's more than enough thrust at 50% butterfly open. I got 5 flights today running the engine that way in 15 mph lumpy air. Delta flew right through that stuff at similar pace as before in still air.

Noise has to be heard to be understood. We will try to take video tomorrow

MTK

Good idea Jason.....I "ll discuss it with him and see what can be done. The 4 5M bolts weigh almost 2 ounces so if some weight could be saved too, it would be bonus.....

In meantime, the backplate of the spinner he is making will be drilled for the 4 bolts. But today I flew without the hand cut spinner; things were a bit smoother. Taking the 2 1/2 ounce spinner off the nose really hardly changed anything in the flying.

speedracerntrixie

My Feedback: (29)

Matt, I'm making progress on my DLE as well. I went back to a 30 degree timing setting and ran the counterbalance spinner I modded up. I'm running one of the Chinese CF spinners with a CF backplate. Never gave it much thought but when I put the backplate on a balancer it was out a tad. I ended up drilling 3 1/2" holes in the light side and then mounted it up with the heavy side opposite the piston and con rod. It made a huge difference. Keep in mind this is mounted on a really light airframe. It's a 33% Laser, the engine is stock and Im running a K&S header MTW canister. AUW is 16 lb even so the vibes really show up especially in the cowl that is only 2 layers of 3.7 oz cloth. I'm running a Falcon CF 23x9 prop that is actually pretty darned light. By my standards it,s a very quiet setup. The engine is now really starting to behave, throttle response is better then it ever has been. I can climb forever at half throttle. I've settled with Stihl HP ultra mixed up with Shell 89 octane at 40-1. IMO once you get the engine to run smoother it just does everything better.

MTK

Shawn,

The Mezjlik 3 blader is quite a bit heavier than the props you are running. But you might want to try a 20x12 3 blader woodie if you can find one. I have not been able to do so. The noise will drop considerably and it should work exceptionally well in a light airframe.

If Bob's electric 3 blader doesn't pan out, I have a couple 20x12 2 blade xoar electric props that can bereshaped, cut and re-assembledas 3 blader woodie, laminated in carbon braid. Should be able to remove 2 ounces off the weight of the Mezjlik prop

cmoulder

Matt, just to be clear, the 20x12 CF props I have are 2-bladers. I thought that you might want to split them and make some 120-deg cuts and reassemble them.

You are still welcome to use them for your experiment, but it would probably be easier to work with your wood props to make a 3-blade version of the hybrids you made before. In any event I will bring them to Pocono and you can decide if they are appropriate.

J Lachowski

My Feedback: (46)

Why not go with a 4 blader from two woodies<ga>

MTK

Joey, Joey, Joey.... the idea is to lose weight.......Consider prop, prop mounting bolts and spinner weigh about 280 grams....Ouch!!

Besides, what are you doing posting in aPETROL thread?? You might get polluted......(LOL)

MTK

I've got16 flights on Delta this far. Primarily set-up flights, getting Delta tuned. Still have a little ways to go but it's flying very well. This model makes melook good even with almost no practice

With the built in reduced throttle, it is easier to manage the awsome power of the 55. But even with it detuned I find I seldom need more than half throttle. The sound it makes is really cool...akin to aHonda motorcyclerather than an Harley.I'll try to taskBobbyto take video this weekend at the PokeURnose contest.